This patch set extends the mempolicy interface to enable new
mempolicies which may require extended data to operate.
MPOL_WEIGHTED_INTERLEAVE is included as an example extension.
Patches 1 and 2 (weighted interleave w/ sysfs globals) can be
an candidate for merge separate from patches 3-11, but 3-11 are
dependent on them, so it is included in the overall RFC.
There are 3 major "phases" in the patch set:
1) Implement MPOL_WEIGHTED_INTERLEAVE with a sysfs extension,
which allows and admin/daemon to set weights via sysfs.
(Patches 1 & 2). Weighted interleave allows for interleave
other than 1:1 (round-robin), such that bandwidth can be used
optimally. For example, a 9:1 interleave between nodes 0 and 1
would place 9 pages on node0 for every 1 page on node1.
2) A refactor of the mempolicy creation mechanism to accept an
extensible argument structure `struct mempolicy_args` to promote
code re-use between the original mempolicy/mbind interfaces and
the new extended mempolicy/mbind interfaces.
(Patches 3-6)
3) Implementation of set_mempolicy2, get_mempolicy2, and mbind2,
along with the addition of task-local weights so that per-task
weights can be registered for MPOL_WEIGHTED_INTERLEAVE.
(Patches 7-11)
A sample numactl extension can be found here to test global weights:
https://github.com/gmprice/numactl/tree/weighted_interleave_master
Additionally, at the bottom of this cover letter is linux test
project tests for backward and forward compatibility, and some
sample software for quick and dirty testing.
= Performance summary =
(tests may have different configurations, see extended info below)
1) MLC (W2) : +38% over DRAM. +264% over default interleave.
MLC (W5) : +40% over DRAM. +226% over default interleave.
2) Stream : -6% to +4% over DRAM, +430% over default interleave.
3) XSBench : +19% over DRAM. +47% over default interleave.
= LTP Testing Summary =
https://github.com/gmprice/ltp/tree/mempolicy2
existing mempolicy & mbind tests: pass
mempolicy & mbind + weighted interleave (global weights): pass
mempolicy2 & mbind2 + weighted interleave (global weights): pass
mempolicy2 & mbind2 + weighted interleave (local weights): pass
= Other test summary =
numactl global weight useage: pass
weight distribution validation: pass
= v4 (full notes moved to bottom) =
- CONFIG_MMU, CONFIG_SYSFS, tools/perf configs
- sysfs attr init build warning
- arch/arm64 syscall wire-ups (Thanks Arnd!)
- Performance tests
=====================================================================
Performance tests - MLC
From - Ravi Jonnalagadda <[email protected]>
Hardware: Single-socket, multiple CXL memory expanders.
Workload: W2
Data Signature: 2:1 read:write
DRAM only bandwidth (GBps): 298.8
DRAM + CXL (default interleave) (GBps): 113.04
DRAM + CXL (weighted interleave)(GBps): 412.5
Gain over DRAM only: 1.38x
Gain over default interleave: 2.64x
Workload: W5
Data Signature: 1:1 read:write
DRAM only bandwidth (GBps): 273.2
DRAM + CXL (default interleave) (GBps): 117.23
DRAM + CXL (weighted interleave)(GBps): 382.7
Gain over DRAM only: 1.4x
Gain over default interleave: 2.26x
=====================================================================
Performance test - Stream
From - Gregory Price <[email protected]>
Hardware: Single socket, single CXL expander
Summary: 64 threads, ~18GB workload, 3GB per array, executed 100 times
Default interleave : -78% (slower than DRAM)
Global weighting : -6% to +4% (workload dependant)
mbind2 weights : +2.5% to +4% (consistently better than DRAM)
dram only:
numactl --cpunodebind=1 --membind=1 ./stream_c.exe --ntimes 100 --array-size 400M --malloc
Function Direction BestRateMBs AvgTime MinTime MaxTime
Copy: 0->0 200923.2 0.032662 0.031853 0.033301
Scale: 0->0 202123.0 0.032526 0.031664 0.032970
Add: 0->0 208873.2 0.047322 0.045961 0.047884
Triad: 0->0 208523.8 0.047262 0.046038 0.048414
CXL-only:
numactl --cpunodebind=1 -w --membind=2 ./stream_c.exe --ntimes 100 --array-size 400M --malloc
Copy: 0->0 22209.7 0.288661 0.288162 0.289342
Scale: 0->0 22288.2 0.287549 0.287147 0.288291
Add: 0->0 24419.1 0.393372 0.393135 0.393735
Triad: 0->0 24484.6 0.392337 0.392083 0.394331
Based on the above, the optimal weights are ~9:1
echo 9 > /sys/kernel/mm/mempolicy/weighted_interleave/node1
echo 1 > /sys/kernel/mm/mempolicy/weighted_interleave/node2
default interleave:
numactl --cpunodebind=1 --interleave=1,2 ./stream_c.exe --ntimes 100 --array-size 400M --malloc
Copy: 0->0 44666.2 0.143671 0.143285 0.144174
Scale: 0->0 44781.6 0.143256 0.142916 0.143713
Add: 0->0 48600.7 0.197719 0.197528 0.197858
Triad: 0->0 48727.5 0.197204 0.197014 0.197439
global weighted interleave:
numactl --cpunodebind=1 -w --interleave=1,2 ./stream_c.exe --ntimes 100 --array-size 400M --malloc
Copy: 0->0 190085.9 0.034289 0.033669 0.034645
Scale: 0->0 207677.4 0.031909 0.030817 0.033061
Add: 0->0 202036.8 0.048737 0.047516 0.053409
Triad: 0->0 217671.5 0.045819 0.044103 0.046755
targted regions w/ global weights (mbind2 on malloc regions special -b flag)
numactl --cpunodebind=1 --membind=1 ./stream_c.exe -b --ntimes 100 --array-size 400M --malloc
Copy: 0->0 205827.0 0.031445 0.031094 0.031984
Scale: 0->0 208171.8 0.031320 0.030744 0.032505
Add: 0->0 217352.0 0.045087 0.044168 0.046515
Triad: 0->0 216884.8 0.045062 0.044263 0.046982
=====================================================================
Performance tests - XSBench
From - Hyeongtak Ji <[email protected]>
Hardware: Single socket, Single CXL memory Expander
NUMA node 0: 56 logical cores, 128 GB memory
NUMA node 2: 96 GB CXL memory
Threads: 56
Lookups: 170,000,000
Summary: +19% over DRAM. +47% over default interleave.
Performance tests - XSBench
1. dram only
$ numactl -m 0 ./XSBench -s XL –p 5000000
Runtime: 36.235 seconds
Lookups/s: 4,691,618
2. default interleave
$ numactl –i 0,2 ./XSBench –s XL –p 5000000
Runtime: 55.243 seconds
Lookups/s: 3,077,293
3. weighted interleave
numactl –w –i 0,2 ./XSBench –s XL –p 5000000
Runtime: 29.262 seconds
Lookups/s: 5,809,513
=====================================================================
(Patch 1) : sysfs addition - /sys/kernel/mm/mempolicy/
This feature provides a way to set interleave weight information under
sysfs at /sys/kernel/mm/mempolicy/weighted_interleave/
The sysfs structure is designed as follows.
$ tree /sys/kernel/mm/mempolicy/
/sys/kernel/mm/mempolicy/
└── weighted_interleave
├── nodeN
└── nodeN+X
'mempolicy' is added to '/sys/kernel/mm/' as a control group for
the mempolicy subsystem.
Internally, weights are represented as an array of unsigned char
static unsigned char iw_table[MAX_NUMNODES];
char was chosen as most reasonable distributions can be represented
as factors <100, and to minimize memory usage (1KB)
We present possible nodes, instead of online nodes, to simplify the
management interface, considering that a) the table is of size
MAX_NUMNODES anyway to simplify fetching of weights (no need to track
sizes, and MAX_NUMNODES is typically at most 1kb), and b) it simplifies
management of hotplug events, allowing for weights to be set prior to
a node coming online, which may be beneficial for immediate use.
the 'weight' of a node (an unsigned char of value 1-255) is the number
of pages that are allocated during a "weighted interleave" round.
(See 'weighted interleave' for more details').
=====================================================================
(Patch 2) set_mempolicy: MPOL_WEIGHTED_INTERLEAVE
Weighted interleave is a new memory policy that interleaves memory
across numa nodes in the provided nodemask based on the weights
described in patch 1 (sysfs global weights).
When a system has multiple NUMA nodes and it becomes bandwidth hungry,
the current MPOL_INTERLEAVE could be an wise option.
However, if those NUMA nodes consist of different types of memory such
as having local DRAM and CXL memory together, the current round-robin
based interleaving policy doesn't maximize the overall bandwidth
because of their different bandwidth characteristics.
Instead, the interleaving can be more efficient when the allocation
policy follows each NUMA nodes' bandwidth weight rather than having 1:1
round-robin allocation.
This patch introduces a new memory policy, MPOL_WEIGHTED_INTERLEAVE,
which enables weighted interleaving between NUMA nodes. Weighted
interleave allows for a proportional distribution of memory across
multiple numa nodes, preferablly apportioned to match the bandwidth
capacity of each node from the perspective of the accessing node.
For example, if a system has 1 CPU node (0), and 2 memory nodes (0,1),
with a relative bandwidth of (100GB/s, 50GB/s) respectively, the
appropriate weight distribution is (2:1).
Weights will be acquired from the global weight array exposed by the
sysfs extension: /sys/kernel/mm/mempolicy/weighted_interleave/
The policy will then allocate the number of pages according to the
set weights. For example, if the weights are (2,1), then 2 pages
will be allocated on node0 for every 1 page allocated on node1.
The new flag MPOL_WEIGHTED_INTERLEAVE can be used in set_mempolicy(2)
and mbind(2).
=====================================================================
(Patches 3-6) Refactoring mempolicy for code-reuse
To avoid multiple paths of mempolicy creation, we should refactor the
existing code to enable the designed extensibility, and refactor
existing users to utilize the new interface (while retaining the
existing userland interface).
This set of patches introduces a new mempolicy_args structure, which
is used to more fully describe a requested mempolicy - to include
existing and future extensions.
/*
* Describes settings of a mempolicy during set/get syscalls and
* kernel internal calls to do_set_mempolicy()
*/
struct mempolicy_args {
unsigned short mode; /* policy mode */
unsigned short mode_flags; /* policy mode flags */
int home_node; /* mbind: use MPOL_MF_HOME_NODE */
nodemask_t *policy_nodes; /* get/set/mbind */
unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
int policy_node; /* get: policy node information */
};
This arg structure will eventually be utilized by the following
interfaces:
mpol_new() - new mempolicy creation
do_get_mempolicy() - acquiring information about mempolicy
do_set_mempolicy() - setting the task mempolicy
do_mbind() - setting a vma mempolicy
do_get_mempolicy() is completely refactored to break it out into
separate functionality based on the flags provided by get_mempolicy(2)
MPOL_F_MEMS_ALLOWED: acquires task->mems_allowed
MPOL_F_ADDR: acquires information on vma policies
MPOL_F_NODE: changes the output for the policy arg to node info
We refactor the get_mempolicy syscall flatten the logic based on these
flags, and aloow for set_mempolicy2() to re-use the underlying logic.
The result of this refactor, and the new mempolicy_args structure, is
that extensions like 'sys_set_mempolicy_home_node' can now be directly
integrated into the initial call to 'set_mempolicy2', and that more
complete information about a mempolicy can be returned with a single
call to 'get_mempolicy2', rather than multiple calls to 'get_mempolicy'
=====================================================================
(Patches 7-10) set_mempolicy2, get_mempolicy2, mbind2
These interfaces are the 'extended' counterpart to their relatives.
They use the userland 'struct mpol_args' structure to communicate a
complete mempolicy configuration to the kernel. This structure
looks very much like the kernel-internal 'struct mempolicy_args':
struct mpol_args {
/* Basic mempolicy settings */
__u16 mode;
__u16 mode_flags;
__s32 home_node;
__aligned_u64 pol_nodes;
__aligned_u64 *il_weights; /* of size pol_maxnodes */
__u64 pol_maxnodes;
__s32 policy_node;
};
The basic mempolicy settings which are shared across all interfaces
are captured at the top of the structure, while extensions such as
'policy_node' and 'addr' are collected beneath.
The syscalls are uniform and defined as follows:
long sys_mbind2(unsigned long addr, unsigned long len,
struct mpol_args *args, size_t usize,
unsigned long flags);
long sys_get_mempolicy2(struct mpol_args *args, size_t size,
unsigned long addr, unsigned long flags);
long sys_set_mempolicy2(struct mpol_args *args, size_t size,
unsigned long flags);
The 'flags' argument for mbind2 is the same as 'mbind', except with
the addition of MPOL_MF_HOME_NODE to denote whether the 'home_node'
field should be utilized.
The 'flags' argument for get_mempolicy2 allows for MPOL_F_ADDR to
allow operating on VMA policies, but MPOL_F_NODE and MPOL_F_MEMS_ALLOWED
behavior has been omitted, since get_mempolicy() provides this already.
The 'flags' argument is not used by 'set_mempolicy' at this time, but
may end up allowing the use of MPOL_MF_HOME_NODE if such functionality
is desired.
The extensions can be summed up as follows:
get_mempolicy2 extensions:
'mode' and 'policy_node' can now be fetched with a single call
rather than multiple with a combination of flags.
- 'mode' will always return the policy mode
- 'policy_node' will replace the functionality of MPOL_F_NODE
- MPOL_F_MEMS_ALLOWED and MPOL_F_NODE are otherwise not supported
set_mempolicy2:
- task-local interleave weights can be set via 'il_weights'
(see next patch)
mbind2:
- 'home_node' field sets policy home node w/ MPOL_MF_HOME_NODE
- task-local interleave weights can be set via 'il_weights'
(see next patch)
=====================================================================
(Patch 11) set_mempolicy2/mbind2: MPOL_WEIGHTED_INTERLEAVE
This patch shows the explicit extension pattern when adding new
policies to mempolicy2/mbind2. This adds the 'il_weights' field
to mpol_args and adds the logic to fill in task-local weights.
There are now two ways to weight a mempolicy: global and local.
To denote which mode the task is in, we add the internal flag:
MPOL_F_GWEIGHT /* Utilize global weights */
When MPOL_F_GWEIGHT is set, the global weights are used, and
when it is not set, task-local weights are used.
Example logic:
if (pol->flags & MPOL_F_GWEIGHT)
pol_weights = iw_table;
else
pol_weights = pol->wil.weights;
set_mempolicy is changed to always set MPOL_F_GWEIGHT, since this
syscall is incapable of passing weights via its interfaces, while
set_mempolicy2 sets MPOL_F_GWEIGHT if MPOL_F_WEIGHTED_INTERLEAVE
is required but (*il_weights) in mpol_args is null.
The operation of task-local weighted is otherwise exactly the
same - except for what occurs on task migration.
On task migration, the system presently has no way of determining
what the new weights "should be", or what the user "intended".
For this reason, we default all weights to '1' and do not allow
weights to be '0'. This means, should a migration occur where
one or more nodes appear into the nodemask - the effective weight
for that node will be '1'. This avoids a potential allocation
failure condition if a migration occurs and introduces a node
which otherwise did not have a weight.
For this reason, users should use task-local weighting when
migrations are not expected, and global weighting when migrations
are expected or possible.
=====================================================================
Existing LTP Tests: https://github.com/gmprice/ltp/tree/mempolicy2
LTP set_mempolicy, get_mempolicy, mbind regression tests:
MPOL_WEIGHTED_INTERLEAVE added manually to test basic functionality
but did not adjust tests for weighting. Basically the weights were
set to 1, which is the default, and it should behavior like standard
MPOL_INTERLEAVE if logic is correct.
== set_mempolicy01
passed 18
failed 0
== set_mempolicy02
passed 10
failed 0
== set_mempolicy03
passed 64
failed 0
== set_mempolicy04
passed 32
failed 0
== set_mempolicy05 - n/a on non-x86
== set_mempolicy06 - set_mempolicy02 + MPOL_WEIGHTED_INTERLEAVE
passed 10
failed 0
== set_mempolicy07 - set_mempolicy04 + MPOL_WEIGHTED_INTERLEAVE
passed 32
failed 0
== get_mempolicy01 - added MPOL_WEIGHTED_INTERLEAVE
passed 12
failed 0
== get_mempolicy02
passed 2
failed 0
== mbind01 - added WEIGHTED_INTERLEAVE
passed 15
failed 0
== mbind02 - added WEIGHTED_INTERLEAVE
passed 4
failed 0
== mbind03 - added WEIGHTED_INTERLEAVE
passed 16
failed 0
== mbind04 - added WEIGHTED_INTERLEAVE
passed 48
failed 0
=====================================================================
New LTP Tests: https://github.com/gmprice/ltp/tree/mempolicy2
set_mempolicy2, get_mempolicy2, mbind2
Took the original set_mempolicy and get_mempolicy tests, and updated
them to utilize the new mempolicy2 interfaces. Added additional tests
for setting task-local weights to validate behavior.
== set_mempolicy201 - set_mempolicy01 equiv
passed 18
failed 0
== set_mempolicy202 - set_mempolicy02 equiv
passed 10
failed 0
== set_mempolicy203 - set_mempolicy03 equiv
passed 64
failed 0
== set_mempolicy204 - set_mempolicy04 equiv
passed 32
failed 0
== set_mempolicy205 - set_mempolicy06 equiv
passed 10
failed 0
== set_mempolicy206 - set_mempolicy07 equiv
passed 32
failed 0
== set_mempolicy207 - MPOL_WEIGHTED_INTERLEAVE with task-local weights
passed 6
failed 0
== get_mempolicy201 - get_mempolicy01 equiv
passed 12
failed 0
== get_mempolicy202 - get_mempolicy02 equiv
passed 2
failed 0
== get_mempolicy203 - NEW - fetch global and local weights
passed 6
failed 0
== mbind201 - mbind01 equiv
passed 15
failed 0
== mbind202 - mbind02 equiv
passed 4
failed 0
== mbind203 - mbind03 equiv
passed 16
failed 0
== mbind204 - mbind04 equiv
passed 48
failed 0
=====================================================================
Basic set_mempolicy2 test
set_mempolicy2 w/ weighted interleave, task-local weights and uses
pthread_create to demonstrate the mempolicy is overwritten by child.
Manually validating the distribution via numa_maps
007c0000 weighted interleave:0-1 heap anon=65794 dirty=65794 active=0 N0=54829 N1=10965 kernelpagesize_kB=4
7f3f2c000000 weighted interleave:0-1 anon=32768 dirty=32768 active=0 N0=5461 N1=27307 kernelpagesize_kB=4
7f3f34000000 weighted interleave:0-1 anon=16384 dirty=16384 active=0 N0=2731 N1=13653 kernelpagesize_kB=4
7f3f3bffe000 weighted interleave:0-1 anon=65538 dirty=65538 active=0 N0=10924 N1=54614 kernelpagesize_kB=4
7f3f5c000000 weighted interleave:0-1 anon=16384 dirty=16384 active=0 N0=2731 N1=13653 kernelpagesize_kB=4
7f3f60dfe000 weighted interleave:0-1 anon=65537 dirty=65537 active=0 N0=54615 N1=10922 kernelpagesize_kB=4
Expected distribution is 5:1 or 1:5 (less node should be ~16.666%)
1) 10965/65794 : 16.6656...
2) 5461/32768 : 16.6656...
3) 2731/16384 : 16.6687...
4) 10924/65538 : 16.6682...
5) 2731/16384 : 16.6687...
6) 10922/65537 : 16.6653...
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <numa.h>
#include <errno.h>
#include <numaif.h>
#include <unistd.h>
#include <pthread.h>
#include <sys/uio.h>
#include <sys/types.h>
#include <stdint.h>
#define MPOL_WEIGHTED_INTERLEAVE 6
#define SET_MEMPOLICY2(a, b) syscall(457, a, b, 0)
#define M256 (1024*1024*256)
#define PAGE_SIZE (4096)
struct mpol_args {
/* Basic mempolicy settings */
uint16_t mode;
uint16_t mode_flags;
int32_t home_node;
uint64_t pol_nodes;
uint64_t il_weights;
uint64_t pol_maxnodes;
int32_t policy_node;
};
struct mpol_args wil_args;
struct bitmask *wil_nodes;
unsigned char *weights;
int total_nodes = -1;
pthread_t tid;
void set_mempolicy_call(int which)
{
weights = (unsigned char *)calloc(total_nodes, sizeof(unsigned char));
wil_nodes = numa_allocate_nodemask();
numa_bitmask_setbit(wil_nodes, 0); weights[0] = which ? 1 : 5;
numa_bitmask_setbit(wil_nodes, 1); weights[1] = which ? 5 : 1;
memset(&wil_args, 0, sizeof(wil_args));
wil_args.mode = MPOL_WEIGHTED_INTERLEAVE;
wil_args.mode_flags = 0;
wil_args.pol_nodes = wil_nodes->maskp;
wil_args.pol_maxnodes = total_nodes;
wil_args.il_weights = weights;
int ret = SET_MEMPOLICY2(&wil_args, sizeof(wil_args));
fprintf(stderr, "set_mempolicy2 result: %d(%s)\n", ret, strerror(errno));
}
void *func(void *arg)
{
char *mainmem = malloc(M256);
int i;
set_mempolicy_call(1); /* weight 1 heavier */
mainmem = malloc(M256);
memset(mainmem, 1, M256);
for (i = 0; i < (M256/PAGE_SIZE); i++) {
mainmem = malloc(PAGE_SIZE);
mainmem[0] = 1;
}
printf("thread done %d\n", getpid());
getchar();
return arg;
}
int main()
{
char * mainmem;
int i;
total_nodes = numa_max_node() + 1;
set_mempolicy_call(0); /* weight 0 heavier */
pthread_create(&tid, NULL, func, NULL);
mainmem = malloc(M256);
memset(mainmem, 1, M256);
for (i = 0; i < (M256/PAGE_SIZE); i++) {
mainmem = malloc(PAGE_SIZE);
mainmem[0] = 1;
}
printf("main done %d\n", getpid());
getchar();
return 0;
}
=====================================================================
numactl (set_mempolicy) w/ global weighting test
numactl fork: https://github.com/gmprice/numactl/tree/weighted_interleave_master
command: numactl -w --interleave=0,1 ./eatmem
result (weights 1:1):
0176a000 weighted interleave:0-1 heap anon=65793 dirty=65793 active=0 N0=32897 N1=32896 kernelpagesize_kB=4
7fceeb9ff000 weighted interleave:0-1 anon=65537 dirty=65537 active=0 N0=32768 N1=32769 kernelpagesize_kB=4
50% distribution is correct
result (weights 5:1):
01b14000 weighted interleave:0-1 heap anon=65793 dirty=65793 active=0 N0=54828 N1=10965 kernelpagesize_kB=4
7f47a1dff000 weighted interleave:0-1 anon=65537 dirty=65537 active=0 N0=54614 N1=10923 kernelpagesize_kB=4
16.666% distribution is correct
result (weights 1:5):
01f07000 weighted interleave:0-1 heap anon=65793 dirty=65793 active=0 N0=10966 N1=54827 kernelpagesize_kB=4
7f17b1dff000 weighted interleave:0-1 anon=65537 dirty=65537 active=0 N0=10923 N1=54614 kernelpagesize_kB=4
16.666% distribution is correct
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main (void)
{
char* mem = malloc(1024*1024*256);
memset(mem, 1, 1024*1024*256);
for (int i = 0; i < ((1024*1024*256)/4096); i++)
{
mem = malloc(4096);
mem[0] = 1;
}
printf("done\n");
getchar();
return 0;
}
=====================================================================
v4:
- CONFIG_MMU COND_SYSCALL fix for mempolicy2/mbind2 syscalls
- ifdef CONFIG_SYSFS handling. If sysfs is disabled, set global
weights to 1 to have it default to standard interleave.
- tools/perf config variation syscall table fix
- sysfs attr init build fix
- arch/arm64 syscall wire-ups (Thanks Arnd!)
=====================================================================
v3:
changes / adds:
- get2(): actually fetch the il_weights (doh!)
- get2(): retrieve home_node
- get2(): addr as arg instead of struct member, drop MPOL_F_NODE flag
get_mempolicy() can be used for this, don't duplicate warts
- get2(): only copy weights if mode is weighted interleave
- mbind2(): addr/len instead of iovec
user can use a for loop...
- sysfs: remove possible_nodes
- sysfs: simplify to weighted_interleave/nodeN
- sysfs: add default weight mechanism (echo > nodeN)
fixes:
- build: syscalls.h mpol_args definition missing
- build: missing `__user` from weights_ptr definition
- bug: uninitialized weight_total in bulk allocator
- bug: bad pointer to copy_struct_from_user in mbind2
- bug: get_mempolicy2 uninitialized data copied to user
- bug: get_vma_mempolicy policy reference counting
- bug: MPOL_F_GWEIGHTS not set correctly in set_mempolicy2
- bug: MPOL_F_GWEIGHTS not set correctly in mbind2
- bug: get_mempolicy2 error not checked on nodemask userland copy
- bug: mbind2 did not parse nodemask correctly
tests:
- ltp branch: https://github.com/gmprice/ltp/tree/mempolicy2
- new set_mempolicy2() tests
1) set_mempolicy() tests w/ new syscall
2) weighted interleave validation
- new get_mempolicy2() tests
1) get_mempolicy() tests w/ new syscall
2) weighted interleave validation
- new mbind2() tests
1) mbind() tests w/ new syscall
- new performance tests (MLC) from Ravi @ Micron
Example:
Workload: W5
Data Signature: 1:1 read:write
DRAM only bandwidth (GBps): 273.2
DRAM + CXL (default interleave) (GBps): 117.23
DRAM + CXL (weighted interleave)(GBps): 382.7
Gain over DRAM only: 1.4x
=====================================================================
v2:
changes / adds:
- flatted weight matrix to an array at requested of Ying Huang
- Updated ABI docs per Davidlohr Bueso request
- change uapi structure to use aligned/fixed-length members
- Implemented weight fetch logic in get_mempolicy2
- mbind2 was changed to take (iovec,len) as function arguments
rather than add them to the uapi structure, since they describe
where to apply the mempolicy - as opposed to being part of it.
fixes:
- fixed bug reported by Seungjun Ha <[email protected]>
Link: https://lore.kernel.org/linux-cxl/20231206080944epcms2p76ebb230b9f4595f5cfcd2531d67ab3ce@epcms2p7/
- fixed bug in mbind2 where MPOL_F_GWEIGHTS was not set when il_weights
was omitted after local weights were added as an option
- fixed bug in interleave logic where an OOB access was made if
next_node_in returned MAX_NUMNODES
- fixed bug in bulk weighted interleave allocator where over-allocation
could occur.
tests:
- LTP: validated existing get_mempolicy, set_mempolicy, and mbind tests
- LTP: validated existing get_mempolicy, set_mempolicy, and mbind with
MPOL_WEIGHTED_INTERLEAVE added.
- basic set_mempolicy2 tests and numactl -w --interleave tests
numactl:
- Sample numactl extension for set_mempolicy available here:
Link: https://github.com/gmprice/numactl/tree/weighted_interleave_master
(added summary of test reports to end of cover letter)
=====================================================================
Suggested-by: Gregory Price <[email protected]>
Suggested-by: Johannes Weiner <[email protected]>
Suggested-by: Hasan Al Maruf <[email protected]>
Suggested-by: Hao Wang <[email protected]>
Suggested-by: Ying Huang <[email protected]>
Suggested-by: Dan Williams <[email protected]>
Suggested-by: Michal Hocko <[email protected]>
Suggested-by: tj <[email protected]>
Suggested-by: Zhongkun He <[email protected]>
Suggested-by: Frank van der Linden <[email protected]>
Suggested-by: John Groves <[email protected]>
Suggested-by: Vinicius Tavares Petrucci <[email protected]>
Suggested-by: Srinivasulu Thanneeru <[email protected]>
Suggested-by: Ravi Jonnalagadda <[email protected]>
Suggested-by: Jonathan Cameron <[email protected]>
Suggested-by: Hyeongtak Ji <[email protected]>
Suggested-by: Rakie Kim <[email protected]>
Suggested-by: Honggyu Kim <[email protected]>
Signed-off-by: Gregory Price <[email protected]>
Gregory Price (10):
mm/mempolicy: introduce MPOL_WEIGHTED_INTERLEAVE for weighted
interleaving
mm/mempolicy: refactor sanitize_mpol_flags for reuse
mm/mempolicy: create struct mempolicy_args for creating new
mempolicies
mm/mempolicy: refactor kernel_get_mempolicy for code re-use
mm/mempolicy: allow home_node to be set by mpol_new
mm/mempolicy: add userland mempolicy arg structure
mm/mempolicy: add set_mempolicy2 syscall
mm/mempolicy: add get_mempolicy2 syscall
mm/mempolicy: add the mbind2 syscall
mm/mempolicy: extend set_mempolicy2 and mbind2 to support weighted
interleave
Rakie Kim (1):
mm/mempolicy: implement the sysfs-based weighted_interleave interface
.../ABI/testing/sysfs-kernel-mm-mempolicy | 4 +
...fs-kernel-mm-mempolicy-weighted-interleave | 22 +
.../admin-guide/mm/numa_memory_policy.rst | 67 ++
arch/alpha/kernel/syscalls/syscall.tbl | 3 +
arch/arm/tools/syscall.tbl | 3 +
arch/arm64/include/asm/unistd.h | 2 +-
arch/arm64/include/asm/unistd32.h | 6 +
arch/m68k/kernel/syscalls/syscall.tbl | 3 +
arch/microblaze/kernel/syscalls/syscall.tbl | 3 +
arch/mips/kernel/syscalls/syscall_n32.tbl | 3 +
arch/mips/kernel/syscalls/syscall_o32.tbl | 3 +
arch/parisc/kernel/syscalls/syscall.tbl | 3 +
arch/powerpc/kernel/syscalls/syscall.tbl | 3 +
arch/s390/kernel/syscalls/syscall.tbl | 3 +
arch/sh/kernel/syscalls/syscall.tbl | 3 +
arch/sparc/kernel/syscalls/syscall.tbl | 3 +
arch/x86/entry/syscalls/syscall_32.tbl | 3 +
arch/x86/entry/syscalls/syscall_64.tbl | 3 +
arch/xtensa/kernel/syscalls/syscall.tbl | 3 +
include/linux/mempolicy.h | 19 +
include/linux/syscalls.h | 8 +
include/uapi/asm-generic/unistd.h | 8 +-
include/uapi/linux/mempolicy.h | 18 +-
kernel/sys_ni.c | 3 +
mm/mempolicy.c | 934 +++++++++++++++---
.../arch/mips/entry/syscalls/syscall_n64.tbl | 3 +
.../arch/powerpc/entry/syscalls/syscall.tbl | 3 +
.../perf/arch/s390/entry/syscalls/syscall.tbl | 3 +
.../arch/x86/entry/syscalls/syscall_64.tbl | 3 +
29 files changed, 1029 insertions(+), 116 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-kernel-mm-mempolicy
create mode 100644 Documentation/ABI/testing/sysfs-kernel-mm-mempolicy-weighted-interleave
--
2.39.1
From: Rakie Kim <[email protected]>
This patch provides a way to set interleave weight information under
sysfs at /sys/kernel/mm/mempolicy/weighted_interleave/nodeN
The sysfs structure is designed as follows.
$ tree /sys/kernel/mm/mempolicy/
/sys/kernel/mm/mempolicy/ [1]
└── weighted_interleave [2]
├── node0 [3]
└── node1
Each file above can be explained as follows.
[1] mm/mempolicy: configuration interface for mempolicy subsystem
[2] weighted_interleave/: config interface for weighted interleave policy
[3] weighted_interleave/nodeN: weight for nodeN
If sysfs is disabled in the config, the global interleave weights
will default to "1" for all nodes.
Signed-off-by: Rakie Kim <[email protected]>
Signed-off-by: Honggyu Kim <[email protected]>
Co-developed-by: Gregory Price <[email protected]>
Signed-off-by: Gregory Price <[email protected]>
Co-developed-by: Hyeongtak Ji <[email protected]>
Signed-off-by: Hyeongtak Ji <[email protected]>
---
.../ABI/testing/sysfs-kernel-mm-mempolicy | 4 +
...fs-kernel-mm-mempolicy-weighted-interleave | 22 +++
mm/mempolicy.c | 156 ++++++++++++++++++
3 files changed, 182 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-kernel-mm-mempolicy
create mode 100644 Documentation/ABI/testing/sysfs-kernel-mm-mempolicy-weighted-interleave
diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-mempolicy b/Documentation/ABI/testing/sysfs-kernel-mm-mempolicy
new file mode 100644
index 000000000000..2dcf24f4384a
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-mempolicy
@@ -0,0 +1,4 @@
+What: /sys/kernel/mm/mempolicy/
+Date: December 2023
+Contact: Linux memory management mailing list <[email protected]>
+Description: Interface for Mempolicy
diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-mempolicy-weighted-interleave b/Documentation/ABI/testing/sysfs-kernel-mm-mempolicy-weighted-interleave
new file mode 100644
index 000000000000..aa27fdf08c19
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-kernel-mm-mempolicy-weighted-interleave
@@ -0,0 +1,22 @@
+What: /sys/kernel/mm/mempolicy/weighted_interleave/
+Date: December 2023
+Contact: Linux memory management mailing list <[email protected]>
+Description: Configuration Interface for the Weighted Interleave policy
+
+What: /sys/kernel/mm/mempolicy/weighted_interleave/nodeN
+Date: December 2023
+Contact: Linux memory management mailing list <[email protected]>
+Description: Weight configuration interface for nodeN
+
+ The interleave weight for a memory node (N). These weights are
+ utilized by processes which have set their mempolicy to
+ MPOL_WEIGHTED_INTERLEAVE and have opted into global weights by
+ omitting a task-local weight array.
+
+ These weights only affect new allocations, and changes at runtime
+ will not cause migrations on already allocated pages.
+
+ Writing an empty string resets the weight value to 1.
+
+ Minimum weight: 1
+ Maximum weight: 255
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 10a590ee1c89..0e77633b07a5 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -131,6 +131,8 @@ static struct mempolicy default_policy = {
static struct mempolicy preferred_node_policy[MAX_NUMNODES];
+static char iw_table[MAX_NUMNODES];
+
/**
* numa_nearest_node - Find nearest node by state
* @node: Node id to start the search
@@ -3067,3 +3069,157 @@ void mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
p += scnprintf(p, buffer + maxlen - p, ":%*pbl",
nodemask_pr_args(&nodes));
}
+
+#ifdef CONFIG_SYSFS
+struct iw_node_attr {
+ struct kobj_attribute kobj_attr;
+ int nid;
+};
+
+static ssize_t node_show(struct kobject *kobj, struct kobj_attribute *attr,
+ char *buf)
+{
+ struct iw_node_attr *node_attr;
+
+ node_attr = container_of(attr, struct iw_node_attr, kobj_attr);
+ return sysfs_emit(buf, "%d\n", iw_table[node_attr->nid]);
+}
+
+static ssize_t node_store(struct kobject *kobj, struct kobj_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct iw_node_attr *node_attr;
+ unsigned char weight = 0;
+
+ node_attr = container_of(attr, struct iw_node_attr, kobj_attr);
+ /* If no input, set default weight to 1 */
+ if (count == 0 || sysfs_streq(buf, ""))
+ weight = 1;
+ else if (kstrtou8(buf, 0, &weight) || !weight)
+ return -EINVAL;
+
+ iw_table[node_attr->nid] = weight;
+ return count;
+}
+
+static struct iw_node_attr *node_attrs[MAX_NUMNODES];
+
+static void sysfs_wi_node_release(struct iw_node_attr *node_attr,
+ struct kobject *parent)
+{
+ if (!node_attr)
+ return;
+ sysfs_remove_file(parent, &node_attr->kobj_attr.attr);
+ kfree(node_attr->kobj_attr.attr.name);
+ kfree(node_attr);
+}
+
+static void sysfs_mempolicy_release(struct kobject *mempolicy_kobj)
+{
+ int i;
+
+ for (i = 0; i < MAX_NUMNODES; i++)
+ sysfs_wi_node_release(node_attrs[i], mempolicy_kobj);
+ kobject_put(mempolicy_kobj);
+}
+
+static const struct kobj_type mempolicy_ktype = {
+ .sysfs_ops = &kobj_sysfs_ops,
+ .release = sysfs_mempolicy_release,
+};
+
+static int add_weight_node(int nid, struct kobject *wi_kobj)
+{
+ struct iw_node_attr *node_attr;
+ char *name;
+
+ node_attr = kzalloc(sizeof(*node_attr), GFP_KERNEL);
+ if (!node_attr)
+ return -ENOMEM;
+
+ name = kasprintf(GFP_KERNEL, "node%d", nid);
+ if (!name) {
+ kfree(node_attr);
+ return -ENOMEM;
+ }
+
+ sysfs_attr_init(&node_attr->kobj_attr.attr);
+ node_attr->kobj_attr.attr.name = name;
+ node_attr->kobj_attr.attr.mode = 0644;
+ node_attr->kobj_attr.show = node_show;
+ node_attr->kobj_attr.store = node_store;
+ node_attr->nid = nid;
+
+ if (sysfs_create_file(wi_kobj, &node_attr->kobj_attr.attr)) {
+ kfree(node_attr->kobj_attr.attr.name);
+ kfree(node_attr);
+ pr_err("failed to add attribute to weighted_interleave\n");
+ return -ENOMEM;
+ }
+
+ node_attrs[nid] = node_attr;
+ return 0;
+}
+
+static int add_weighted_interleave_group(struct kobject *root_kobj)
+{
+ struct kobject *wi_kobj;
+ int nid, err;
+
+ wi_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
+ if (!wi_kobj)
+ return -ENOMEM;
+
+ err = kobject_init_and_add(wi_kobj, &mempolicy_ktype, root_kobj,
+ "weighted_interleave");
+ if (err) {
+ kfree(wi_kobj);
+ return err;
+ }
+
+ memset(node_attrs, 0, sizeof(node_attrs));
+ for_each_node_state(nid, N_POSSIBLE) {
+ err = add_weight_node(nid, wi_kobj);
+ if (err) {
+ pr_err("failed to add sysfs [node%d]\n", nid);
+ break;
+ }
+ }
+ if (err)
+ kobject_put(wi_kobj);
+ return 0;
+}
+
+static int __init mempolicy_sysfs_init(void)
+{
+ int err;
+ struct kobject *root_kobj;
+
+ memset(&iw_table, 1, sizeof(iw_table));
+
+ root_kobj = kobject_create_and_add("mempolicy", mm_kobj);
+ if (!root_kobj) {
+ pr_err("failed to add mempolicy kobject to the system\n");
+ return -ENOMEM;
+ }
+
+ err = add_weighted_interleave_group(root_kobj);
+
+ if (err)
+ kobject_put(root_kobj);
+ return err;
+
+}
+#else
+static int __init mempolicy_sysfs_init(void)
+{
+ /*
+ * if sysfs is not enabled MPOL_WEIGHTED_INTERLEAVE defaults to
+ * MPOL_INTERLEAVE behavior, but is still defined separately to
+ * allow task-local weighted interleave to operate as intended.
+ */
+ memset(&iw_table, 1, sizeof(iw_table));
+ return 0;
+}
+#endif /* CONFIG_SYSFS */
+late_initcall(mempolicy_sysfs_init);
--
2.39.1
When a system has multiple NUMA nodes and it becomes bandwidth hungry,
the current MPOL_INTERLEAVE could be an wise option.
However, if those NUMA nodes consist of different types of memory such
as having local DRAM and CXL memory together, the current round-robin
based interleaving policy doesn't maximize the overall bandwidth because
of their different bandwidth characteristics.
Instead, the interleaving can be more efficient when the allocation
policy follows each NUMA nodes' bandwidth weight rather than having 1:1
round-robin allocation.
This patch introduces a new memory policy, MPOL_WEIGHTED_INTERLEAVE, which
enables weighted interleaving between NUMA nodes. Weighted interleave
allows for a proportional distribution of memory across multiple numa
nodes, preferablly apportioned to match the bandwidth capacity of each
node from the perspective of the accessing node.
For example, if a system has 1 CPU node (0), and 2 memory nodes (0,1),
with a relative bandwidth of (100GB/s, 50GB/s) respectively, the
appropriate weight distribution is (2:1).
Weights will be acquired from the global weight matrix exposed by the
sysfs extension: /sys/kernel/mm/mempolicy/weighted_interleave/
The policy will then allocate the number of pages according to the
set weights. For example, if the weights are (2,1), then 2 pages
will be allocated on node0 for every 1 page allocated on node1.
The new flag MPOL_WEIGHTED_INTERLEAVE can be used in set_mempolicy(2)
and mbind(2).
There are 3 integration points:
weighted_interleave_nodes:
Counts the number of allocations as they occur, and applies the
weight for the current node. When the weight reaches 0, switch
to the next node. Applied by `mempolicy_slab_node()` and
`policy_nodemask()`
weighted_interleave_nid:
Gets the total weight of the nodemask as well as each individual
node weight, then calculates the node based on the given index.
Applied by `policy_nodemask()` and `mpol_misplaced()`
bulk_array_weighted_interleave:
Gets the total weight of the nodemask as well as each individual
node weight, then calculates the number of "interleave rounds" as
well as any delta ("partial round"). Calculates the number of
pages for each node and allocates them.
If a node was scheduled for interleave via interleave_nodes, the
current weight (pol->cur_weight) will be allocated first, before
the remaining bulk calculation is done. This simplifies the
calculation at the cost of an additional allocation call.
One piece of complexity is the interaction between a recent refactor
which split the logic to acquire the "ilx" (interleave index) of an
allocation and the actually application of the interleave. The
calculation of the `interleave index` is done by `get_vma_policy()`,
while the actual selection of the node will be later appliex by the
relevant weighted_interleave function.
If CONFIG_SYSFS is disabled, the weight table will be initialized
to set all nodes to weight 1, but the weighting code is still called.
This is so that task-local weights (future patch) can still be
engaged cleanly without ifdef spaghetti.
Suggested-by: Hasan Al Maruf <[email protected]>
Signed-off-by: Gregory Price <[email protected]>
Co-developed-by: Rakie Kim <[email protected]>
Signed-off-by: Rakie Kim <[email protected]>
Co-developed-by: Honggyu Kim <[email protected]>
Signed-off-by: Honggyu Kim <[email protected]>
Co-developed-by: Hyeongtak Ji <[email protected]>
Signed-off-by: Hyeongtak Ji <[email protected]>
Co-developed-by: Srinivasulu Thanneeru <[email protected]>
Signed-off-by: Srinivasulu Thanneeru <[email protected]>
Co-developed-by: Ravi Jonnalagadda <[email protected]>
Signed-off-by: Ravi Jonnalagadda <[email protected]>
---
.../admin-guide/mm/numa_memory_policy.rst | 11 +
include/linux/mempolicy.h | 5 +
include/uapi/linux/mempolicy.h | 1 +
mm/mempolicy.c | 197 +++++++++++++++++-
4 files changed, 211 insertions(+), 3 deletions(-)
diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst
index eca38fa81e0f..d2c8e712785b 100644
--- a/Documentation/admin-guide/mm/numa_memory_policy.rst
+++ b/Documentation/admin-guide/mm/numa_memory_policy.rst
@@ -250,6 +250,17 @@ MPOL_PREFERRED_MANY
can fall back to all existing numa nodes. This is effectively
MPOL_PREFERRED allowed for a mask rather than a single node.
+MPOL_WEIGHTED_INTERLEAVE
+ This mode operates the same as MPOL_INTERLEAVE, except that
+ interleaving behavior is executed based on weights set in
+ /sys/kernel/mm/mempolicy/weighted_interleave/
+
+ Weighted interleave allocations pages on nodes according to
+ their weight. For example if nodes [0,1] are weighted [5,2]
+ respectively, 5 pages will be allocated on node0 for every
+ 2 pages allocated on node1. This can better distribute data
+ according to bandwidth on heterogeneous memory systems.
+
NUMA memory policy supports the following optional mode flags:
MPOL_F_STATIC_NODES
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index 931b118336f4..ba09167e80f7 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -54,6 +54,11 @@ struct mempolicy {
nodemask_t cpuset_mems_allowed; /* relative to these nodes */
nodemask_t user_nodemask; /* nodemask passed by user */
} w;
+
+ /* Weighted interleave settings */
+ struct {
+ unsigned char cur_weight;
+ } wil;
};
/*
diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h
index a8963f7ef4c2..1f9bb10d1a47 100644
--- a/include/uapi/linux/mempolicy.h
+++ b/include/uapi/linux/mempolicy.h
@@ -23,6 +23,7 @@ enum {
MPOL_INTERLEAVE,
MPOL_LOCAL,
MPOL_PREFERRED_MANY,
+ MPOL_WEIGHTED_INTERLEAVE,
MPOL_MAX, /* always last member of enum */
};
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 0e77633b07a5..0a180c670f0c 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -305,6 +305,7 @@ static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
policy->mode = mode;
policy->flags = flags;
policy->home_node = NUMA_NO_NODE;
+ policy->wil.cur_weight = 0;
return policy;
}
@@ -417,6 +418,10 @@ static const struct mempolicy_operations mpol_ops[MPOL_MAX] = {
.create = mpol_new_nodemask,
.rebind = mpol_rebind_preferred,
},
+ [MPOL_WEIGHTED_INTERLEAVE] = {
+ .create = mpol_new_nodemask,
+ .rebind = mpol_rebind_nodemask,
+ },
};
static bool migrate_folio_add(struct folio *folio, struct list_head *foliolist,
@@ -838,7 +843,8 @@ static long do_set_mempolicy(unsigned short mode, unsigned short flags,
old = current->mempolicy;
current->mempolicy = new;
- if (new && new->mode == MPOL_INTERLEAVE)
+ if (new && (new->mode == MPOL_INTERLEAVE ||
+ new->mode == MPOL_WEIGHTED_INTERLEAVE))
current->il_prev = MAX_NUMNODES-1;
task_unlock(current);
mpol_put(old);
@@ -864,6 +870,7 @@ static void get_policy_nodemask(struct mempolicy *pol, nodemask_t *nodes)
case MPOL_INTERLEAVE:
case MPOL_PREFERRED:
case MPOL_PREFERRED_MANY:
+ case MPOL_WEIGHTED_INTERLEAVE:
*nodes = pol->nodes;
break;
case MPOL_LOCAL:
@@ -948,6 +955,13 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
} else if (pol == current->mempolicy &&
pol->mode == MPOL_INTERLEAVE) {
*policy = next_node_in(current->il_prev, pol->nodes);
+ } else if (pol == current->mempolicy &&
+ (pol->mode == MPOL_WEIGHTED_INTERLEAVE)) {
+ if (pol->wil.cur_weight)
+ *policy = current->il_prev;
+ else
+ *policy = next_node_in(current->il_prev,
+ pol->nodes);
} else {
err = -EINVAL;
goto out;
@@ -1777,7 +1791,8 @@ struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
pol = __get_vma_policy(vma, addr, ilx);
if (!pol)
pol = get_task_policy(current);
- if (pol->mode == MPOL_INTERLEAVE) {
+ if (pol->mode == MPOL_INTERLEAVE ||
+ pol->mode == MPOL_WEIGHTED_INTERLEAVE) {
*ilx += vma->vm_pgoff >> order;
*ilx += (addr - vma->vm_start) >> (PAGE_SHIFT + order);
}
@@ -1827,6 +1842,24 @@ bool apply_policy_zone(struct mempolicy *policy, enum zone_type zone)
return zone >= dynamic_policy_zone;
}
+static unsigned int weighted_interleave_nodes(struct mempolicy *policy)
+{
+ unsigned int next;
+ struct task_struct *me = current;
+
+ next = next_node_in(me->il_prev, policy->nodes);
+ if (next == MAX_NUMNODES)
+ return next;
+
+ if (!policy->wil.cur_weight)
+ policy->wil.cur_weight = iw_table[next];
+
+ policy->wil.cur_weight--;
+ if (!policy->wil.cur_weight)
+ me->il_prev = next;
+ return next;
+}
+
/* Do dynamic interleaving for a process */
static unsigned int interleave_nodes(struct mempolicy *policy)
{
@@ -1861,6 +1894,9 @@ unsigned int mempolicy_slab_node(void)
case MPOL_INTERLEAVE:
return interleave_nodes(policy);
+ case MPOL_WEIGHTED_INTERLEAVE:
+ return weighted_interleave_nodes(policy);
+
case MPOL_BIND:
case MPOL_PREFERRED_MANY:
{
@@ -1885,6 +1921,41 @@ unsigned int mempolicy_slab_node(void)
}
}
+static unsigned int weighted_interleave_nid(struct mempolicy *pol, pgoff_t ilx)
+{
+ nodemask_t nodemask = pol->nodes;
+ unsigned int target, weight_total = 0;
+ int nid;
+ unsigned char weights[MAX_NUMNODES];
+ unsigned char weight;
+
+ barrier();
+
+ /* first ensure we have a valid nodemask */
+ nid = first_node(nodemask);
+ if (nid == MAX_NUMNODES)
+ return nid;
+
+ /* Then collect weights on stack and calculate totals */
+ for_each_node_mask(nid, nodemask) {
+ weight = iw_table[nid];
+ weight_total += weight;
+ weights[nid] = weight;
+ }
+
+ /* Finally, calculate the node offset based on totals */
+ target = (unsigned int)ilx % weight_total;
+ nid = first_node(nodemask);
+ while (target) {
+ weight = weights[nid];
+ if (target < weight)
+ break;
+ target -= weight;
+ nid = next_node_in(nid, nodemask);
+ }
+ return nid;
+}
+
/*
* Do static interleaving for interleave index @ilx. Returns the ilx'th
* node in pol->nodes (starting from ilx=0), wrapping around if ilx
@@ -1953,6 +2024,11 @@ static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *pol,
*nid = (ilx == NO_INTERLEAVE_INDEX) ?
interleave_nodes(pol) : interleave_nid(pol, ilx);
break;
+ case MPOL_WEIGHTED_INTERLEAVE:
+ *nid = (ilx == NO_INTERLEAVE_INDEX) ?
+ weighted_interleave_nodes(pol) :
+ weighted_interleave_nid(pol, ilx);
+ break;
}
return nodemask;
@@ -2014,6 +2090,7 @@ bool init_nodemask_of_mempolicy(nodemask_t *mask)
case MPOL_PREFERRED_MANY:
case MPOL_BIND:
case MPOL_INTERLEAVE:
+ case MPOL_WEIGHTED_INTERLEAVE:
*mask = mempolicy->nodes;
break;
@@ -2113,7 +2190,8 @@ struct page *alloc_pages_mpol(gfp_t gfp, unsigned int order,
* If the policy is interleave or does not allow the current
* node in its nodemask, we allocate the standard way.
*/
- if (pol->mode != MPOL_INTERLEAVE &&
+ if ((pol->mode != MPOL_INTERLEAVE &&
+ pol->mode != MPOL_WEIGHTED_INTERLEAVE) &&
(!nodemask || node_isset(nid, *nodemask))) {
/*
* First, try to allocate THP only on local node, but
@@ -2249,6 +2327,106 @@ static unsigned long alloc_pages_bulk_array_interleave(gfp_t gfp,
return total_allocated;
}
+static unsigned long alloc_pages_bulk_array_weighted_interleave(gfp_t gfp,
+ struct mempolicy *pol, unsigned long nr_pages,
+ struct page **page_array)
+{
+ struct task_struct *me = current;
+ unsigned long total_allocated = 0;
+ unsigned long nr_allocated;
+ unsigned long rounds;
+ unsigned long node_pages, delta;
+ unsigned char weight;
+ unsigned char weights[MAX_NUMNODES];
+ unsigned int weight_total = 0;
+ unsigned long rem_pages = nr_pages;
+ nodemask_t nodes = pol->nodes;
+ int nnodes, node, prev_node;
+ int i;
+
+ /* Stabilize the nodemask on the stack */
+ barrier();
+
+ nnodes = nodes_weight(nodes);
+
+ /* Collect weights and save them on stack so they don't change */
+ for_each_node_mask(node, nodes) {
+ weight = iw_table[node];
+ weight_total += weight;
+ weights[node] = weight;
+ }
+
+ /* Continue allocating from most recent node and adjust the nr_pages */
+ if (pol->wil.cur_weight) {
+ node = next_node_in(me->il_prev, nodes);
+ node_pages = pol->wil.cur_weight;
+ if (node_pages > rem_pages)
+ node_pages = rem_pages;
+ nr_allocated = __alloc_pages_bulk(gfp, node, NULL, node_pages,
+ NULL, page_array);
+ page_array += nr_allocated;
+ total_allocated += nr_allocated;
+ /* if that's all the pages, no need to interleave */
+ if (rem_pages <= pol->wil.cur_weight) {
+ pol->wil.cur_weight -= rem_pages;
+ return total_allocated;
+ }
+ /* Otherwise we adjust nr_pages down, and continue from there */
+ rem_pages -= pol->wil.cur_weight;
+ pol->wil.cur_weight = 0;
+ prev_node = node;
+ }
+
+ /* Now we can continue allocating as if from 0 instead of an offset */
+ rounds = rem_pages / weight_total;
+ delta = rem_pages % weight_total;
+ for (i = 0; i < nnodes; i++) {
+ node = next_node_in(prev_node, nodes);
+ weight = weights[node];
+ node_pages = weight * rounds;
+ if (delta) {
+ if (delta > weight) {
+ node_pages += weight;
+ delta -= weight;
+ } else {
+ node_pages += delta;
+ delta = 0;
+ }
+ }
+ /* We may not make it all the way around */
+ if (!node_pages)
+ break;
+ /* If an over-allocation would occur, floor it */
+ if (node_pages + total_allocated > nr_pages) {
+ node_pages = nr_pages - total_allocated;
+ delta = 0;
+ }
+ nr_allocated = __alloc_pages_bulk(gfp, node, NULL, node_pages,
+ NULL, page_array);
+ page_array += nr_allocated;
+ total_allocated += nr_allocated;
+ prev_node = node;
+ }
+
+ /*
+ * Finally, we need to update me->il_prev and pol->wil.cur_weight
+ * if there were overflow pages, but not equivalent to the node
+ * weight, set the cur_weight to node_weight - delta and the
+ * me->il_prev to the previous node. Otherwise if it was perfect
+ * we can simply set il_prev to node and cur_weight to 0
+ */
+ if (node_pages) {
+ me->il_prev = prev_node;
+ node_pages %= weight;
+ pol->wil.cur_weight = weight - node_pages;
+ } else {
+ me->il_prev = node;
+ pol->wil.cur_weight = 0;
+ }
+
+ return total_allocated;
+}
+
static unsigned long alloc_pages_bulk_array_preferred_many(gfp_t gfp, int nid,
struct mempolicy *pol, unsigned long nr_pages,
struct page **page_array)
@@ -2289,6 +2467,11 @@ unsigned long alloc_pages_bulk_array_mempolicy(gfp_t gfp,
return alloc_pages_bulk_array_interleave(gfp, pol,
nr_pages, page_array);
+ if (pol->mode == MPOL_WEIGHTED_INTERLEAVE)
+ return alloc_pages_bulk_array_weighted_interleave(gfp, pol,
+ nr_pages,
+ page_array);
+
if (pol->mode == MPOL_PREFERRED_MANY)
return alloc_pages_bulk_array_preferred_many(gfp,
numa_node_id(), pol, nr_pages, page_array);
@@ -2364,6 +2547,7 @@ bool __mpol_equal(struct mempolicy *a, struct mempolicy *b)
case MPOL_INTERLEAVE:
case MPOL_PREFERRED:
case MPOL_PREFERRED_MANY:
+ case MPOL_WEIGHTED_INTERLEAVE:
return !!nodes_equal(a->nodes, b->nodes);
case MPOL_LOCAL:
return true;
@@ -2500,6 +2684,10 @@ int mpol_misplaced(struct folio *folio, struct vm_area_struct *vma,
polnid = interleave_nid(pol, ilx);
break;
+ case MPOL_WEIGHTED_INTERLEAVE:
+ polnid = weighted_interleave_nid(pol, ilx);
+ break;
+
case MPOL_PREFERRED:
if (node_isset(curnid, pol->nodes))
goto out;
@@ -2874,6 +3062,7 @@ static const char * const policy_modes[] =
[MPOL_PREFERRED] = "prefer",
[MPOL_BIND] = "bind",
[MPOL_INTERLEAVE] = "interleave",
+ [MPOL_WEIGHTED_INTERLEAVE] = "weighted interleave",
[MPOL_LOCAL] = "local",
[MPOL_PREFERRED_MANY] = "prefer (many)",
};
@@ -2933,6 +3122,7 @@ int mpol_parse_str(char *str, struct mempolicy **mpol)
}
break;
case MPOL_INTERLEAVE:
+ case MPOL_WEIGHTED_INTERLEAVE:
/*
* Default to online nodes with memory if no nodelist
*/
@@ -3043,6 +3233,7 @@ void mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
case MPOL_PREFERRED_MANY:
case MPOL_BIND:
case MPOL_INTERLEAVE:
+ case MPOL_WEIGHTED_INTERLEAVE:
nodes = pol->nodes;
break;
default:
--
2.39.1
split sanitize_mpol_flags into sanitize and validate.
Sanitize is used by set_mempolicy to split (int mode) into mode
and mode_flags, and then validates them.
Validate validates already split flags.
Validate will be reused for new syscalls that accept already
split mode and mode_flags.
Signed-off-by: Gregory Price <[email protected]>
---
mm/mempolicy.c | 29 ++++++++++++++++++++++-------
1 file changed, 22 insertions(+), 7 deletions(-)
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 0a180c670f0c..59ac0da24f56 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1463,24 +1463,39 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0;
}
-/* Basic parameter sanity check used by both mbind() and set_mempolicy() */
-static inline int sanitize_mpol_flags(int *mode, unsigned short *flags)
+/*
+ * Basic parameter sanity check used by mbind/set_mempolicy
+ * May modify flags to include internal flags (e.g. MPOL_F_MOF/F_MORON)
+ */
+static inline int validate_mpol_flags(unsigned short mode, unsigned short *flags)
{
- *flags = *mode & MPOL_MODE_FLAGS;
- *mode &= ~MPOL_MODE_FLAGS;
-
- if ((unsigned int)(*mode) >= MPOL_MAX)
+ if ((unsigned int)(mode) >= MPOL_MAX)
return -EINVAL;
if ((*flags & MPOL_F_STATIC_NODES) && (*flags & MPOL_F_RELATIVE_NODES))
return -EINVAL;
if (*flags & MPOL_F_NUMA_BALANCING) {
- if (*mode != MPOL_BIND)
+ if (mode != MPOL_BIND)
return -EINVAL;
*flags |= (MPOL_F_MOF | MPOL_F_MORON);
}
return 0;
}
+/*
+ * Used by mbind/set_memplicy to split and validate mode/flags
+ * set_mempolicy combines (mode | flags), split them out into separate
+ * fields and return just the mode in mode_arg and flags in flags.
+ */
+static inline int sanitize_mpol_flags(int *mode_arg, unsigned short *flags)
+{
+ unsigned short mode = (*mode_arg & ~MPOL_MODE_FLAGS);
+
+ *flags = *mode_arg & MPOL_MODE_FLAGS;
+ *mode_arg = mode;
+
+ return validate_mpol_flags(mode, flags);
+}
+
static long kernel_mbind(unsigned long start, unsigned long len,
unsigned long mode, const unsigned long __user *nmask,
unsigned long maxnode, unsigned int flags)
--
2.39.1
This patch adds a new kernel structure `struct mempolicy_args`,
intended to be used for an extensible get/set_mempolicy interface.
This implements the fields required to support the existing syscall
interfaces interfaces, but does not expose any user-facing arg
structure.
mpol_new is refactored to take the argument structure so that future
mempolicy extensions can all be managed in the mempolicy constructor.
The get_mempolicy and mbind syscalls are refactored to utilize the
new argument structure, as are all the callers of mpol_new() and
do_set_mempolicy.
Signed-off-by: Gregory Price <[email protected]>
---
include/linux/mempolicy.h | 12 +++++++
mm/mempolicy.c | 69 +++++++++++++++++++++++++++++----------
2 files changed, 63 insertions(+), 18 deletions(-)
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index ba09167e80f7..aeac19dfc2b6 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -61,6 +61,18 @@ struct mempolicy {
} wil;
};
+/*
+ * Describes settings of a mempolicy during set/get syscalls and
+ * kernel internal calls to do_set_mempolicy()
+ */
+struct mempolicy_args {
+ unsigned short mode; /* policy mode */
+ unsigned short mode_flags; /* policy mode flags */
+ int home_node; /* mbind: use MPOL_MF_HOME_NODE */
+ nodemask_t *policy_nodes; /* get/set/mbind */
+ int policy_node; /* get: policy node information */
+};
+
/*
* Support for managing mempolicy data objects (clone, copy, destroy)
* The default fast path of a NULL MPOL_DEFAULT policy is always inlined.
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 59ac0da24f56..42037b7ff6d6 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -265,10 +265,12 @@ static int mpol_set_nodemask(struct mempolicy *pol,
* This function just creates a new policy, does some check and simple
* initialization. You must invoke mpol_set_nodemask() to set nodes.
*/
-static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
- nodemask_t *nodes)
+static struct mempolicy *mpol_new(struct mempolicy_args *args)
{
struct mempolicy *policy;
+ unsigned short mode = args->mode;
+ unsigned short flags = args->mode_flags;
+ nodemask_t *nodes = args->policy_nodes;
if (mode == MPOL_DEFAULT) {
if (nodes && !nodes_empty(*nodes))
@@ -817,8 +819,7 @@ static int mbind_range(struct vma_iterator *vmi, struct vm_area_struct *vma,
}
/* Set the process memory policy */
-static long do_set_mempolicy(unsigned short mode, unsigned short flags,
- nodemask_t *nodes)
+static long do_set_mempolicy(struct mempolicy_args *args)
{
struct mempolicy *new, *old;
NODEMASK_SCRATCH(scratch);
@@ -827,14 +828,14 @@ static long do_set_mempolicy(unsigned short mode, unsigned short flags,
if (!scratch)
return -ENOMEM;
- new = mpol_new(mode, flags, nodes);
+ new = mpol_new(args);
if (IS_ERR(new)) {
ret = PTR_ERR(new);
goto out;
}
task_lock(current);
- ret = mpol_set_nodemask(new, nodes, scratch);
+ ret = mpol_set_nodemask(new, args->policy_nodes, scratch);
if (ret) {
task_unlock(current);
mpol_put(new);
@@ -1232,8 +1233,7 @@ static struct folio *alloc_migration_target_by_mpol(struct folio *src,
#endif
static long do_mbind(unsigned long start, unsigned long len,
- unsigned short mode, unsigned short mode_flags,
- nodemask_t *nmask, unsigned long flags)
+ struct mempolicy_args *margs, unsigned long flags)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma, *prev;
@@ -1253,7 +1253,7 @@ static long do_mbind(unsigned long start, unsigned long len,
if (start & ~PAGE_MASK)
return -EINVAL;
- if (mode == MPOL_DEFAULT)
+ if (margs->mode == MPOL_DEFAULT)
flags &= ~MPOL_MF_STRICT;
len = PAGE_ALIGN(len);
@@ -1264,7 +1264,7 @@ static long do_mbind(unsigned long start, unsigned long len,
if (end == start)
return 0;
- new = mpol_new(mode, mode_flags, nmask);
+ new = mpol_new(margs);
if (IS_ERR(new))
return PTR_ERR(new);
@@ -1281,7 +1281,8 @@ static long do_mbind(unsigned long start, unsigned long len,
NODEMASK_SCRATCH(scratch);
if (scratch) {
mmap_write_lock(mm);
- err = mpol_set_nodemask(new, nmask, scratch);
+ err = mpol_set_nodemask(new, margs->policy_nodes,
+ scratch);
if (err)
mmap_write_unlock(mm);
} else
@@ -1295,7 +1296,7 @@ static long do_mbind(unsigned long start, unsigned long len,
* Lock the VMAs before scanning for pages to migrate,
* to ensure we don't miss a concurrently inserted page.
*/
- nr_failed = queue_pages_range(mm, start, end, nmask,
+ nr_failed = queue_pages_range(mm, start, end, margs->policy_nodes,
flags | MPOL_MF_INVERT | MPOL_MF_WRLOCK, &pagelist);
if (nr_failed < 0) {
@@ -1500,6 +1501,7 @@ static long kernel_mbind(unsigned long start, unsigned long len,
unsigned long mode, const unsigned long __user *nmask,
unsigned long maxnode, unsigned int flags)
{
+ struct mempolicy_args margs;
unsigned short mode_flags;
nodemask_t nodes;
int lmode = mode;
@@ -1514,7 +1516,12 @@ static long kernel_mbind(unsigned long start, unsigned long len,
if (err)
return err;
- return do_mbind(start, len, lmode, mode_flags, &nodes, flags);
+ memset(&margs, 0, sizeof(margs));
+ margs.mode = lmode;
+ margs.mode_flags = mode_flags;
+ margs.policy_nodes = &nodes;
+
+ return do_mbind(start, len, &margs, flags);
}
SYSCALL_DEFINE4(set_mempolicy_home_node, unsigned long, start, unsigned long, len,
@@ -1595,6 +1602,7 @@ SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len,
static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask,
unsigned long maxnode)
{
+ struct mempolicy_args args;
unsigned short mode_flags;
nodemask_t nodes;
int lmode = mode;
@@ -1608,7 +1616,12 @@ static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask,
if (err)
return err;
- return do_set_mempolicy(lmode, mode_flags, &nodes);
+ memset(&args, 0, sizeof(args));
+ args.mode = lmode;
+ args.mode_flags = mode_flags;
+ args.policy_nodes = &nodes;
+
+ return do_set_mempolicy(&args);
}
SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask,
@@ -2890,6 +2903,7 @@ static int shared_policy_replace(struct shared_policy *sp, pgoff_t start,
void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
{
int ret;
+ struct mempolicy_args margs;
sp->root = RB_ROOT; /* empty tree == default mempolicy */
rwlock_init(&sp->lock);
@@ -2902,8 +2916,12 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
if (!scratch)
goto put_mpol;
+ memset(&margs, 0, sizeof(margs));
+ margs.mode = mpol->mode;
+ margs.mode_flags = mpol->flags;
+ margs.policy_nodes = &mpol->w.user_nodemask;
/* contextualize the tmpfs mount point mempolicy to this file */
- npol = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask);
+ npol = mpol_new(&margs);
if (IS_ERR(npol))
goto free_scratch; /* no valid nodemask intersection */
@@ -3011,6 +3029,7 @@ static inline void __init check_numabalancing_enable(void)
void __init numa_policy_init(void)
{
+ struct mempolicy_args args;
nodemask_t interleave_nodes;
unsigned long largest = 0;
int nid, prefer = 0;
@@ -3056,7 +3075,11 @@ void __init numa_policy_init(void)
if (unlikely(nodes_empty(interleave_nodes)))
node_set(prefer, interleave_nodes);
- if (do_set_mempolicy(MPOL_INTERLEAVE, 0, &interleave_nodes))
+ memset(&args, 0, sizeof(args));
+ args.mode = MPOL_INTERLEAVE;
+ args.policy_nodes = &interleave_nodes;
+
+ if (do_set_mempolicy(&args))
pr_err("%s: interleaving failed\n", __func__);
check_numabalancing_enable();
@@ -3065,7 +3088,12 @@ void __init numa_policy_init(void)
/* Reset policy of current process to default */
void numa_default_policy(void)
{
- do_set_mempolicy(MPOL_DEFAULT, 0, NULL);
+ struct mempolicy_args args;
+
+ memset(&args, 0, sizeof(args));
+ args.mode = MPOL_DEFAULT;
+
+ do_set_mempolicy(&args);
}
/*
@@ -3095,6 +3123,7 @@ static const char * const policy_modes[] =
*/
int mpol_parse_str(char *str, struct mempolicy **mpol)
{
+ struct mempolicy_args margs;
struct mempolicy *new = NULL;
unsigned short mode_flags;
nodemask_t nodes;
@@ -3181,7 +3210,11 @@ int mpol_parse_str(char *str, struct mempolicy **mpol)
goto out;
}
- new = mpol_new(mode, mode_flags, &nodes);
+ memset(&margs, 0, sizeof(margs));
+ margs.mode = mode;
+ margs.mode_flags = mode_flags;
+ margs.policy_nodes = &nodes;
+ new = mpol_new(&margs);
if (IS_ERR(new))
goto out;
--
2.39.1
Pull operation flag checking from inside do_get_mempolicy out
to kernel_get_mempolicy. This allows us to flatten the
internal code, and break it into separate functions for future
syscalls (get_mempolicy2, process_get_mempolicy) to re-use the
code, even after additional extensions are made.
The primary change is that the flag is treated as the multiplexer
that it actually is. For get_mempolicy, the flags represents 3
different primary operations:
if (flags & MPOL_F_MEMS_ALLOWED)
return task->mems_allowed
else if (flags & MPOL_F_ADDR)
return vma mempolicy information
else
return task mempolicy information
Plus the behavior modifying flag:
if (flags & MPOL_F_NODE)
change the return value of (int __user *policy)
based on whether MPOL_F_ADDR was set.
The original behavior of get_mempolicy is retained, but we utilize
the new mempolicy_args structure to pass the operations down the
stack. This will allow us to extend the internal functions without
affecting the legacy behavior of get_mempolicy.
Signed-off-by: Gregory Price <[email protected]>
---
mm/mempolicy.c | 245 +++++++++++++++++++++++++++++++------------------
1 file changed, 155 insertions(+), 90 deletions(-)
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 42037b7ff6d6..4426365a353d 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -895,106 +895,111 @@ static int lookup_node(struct mm_struct *mm, unsigned long addr)
return ret;
}
-/* Retrieve NUMA policy */
-static long do_get_mempolicy(int *policy, nodemask_t *nmask,
- unsigned long addr, unsigned long flags)
+/* Retrieve the mems_allowed for current task */
+static inline long do_get_mems_allowed(nodemask_t *nmask)
{
- int err;
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma = NULL;
- struct mempolicy *pol = current->mempolicy, *pol_refcount = NULL;
+ task_lock(current);
+ *nmask = cpuset_current_mems_allowed;
+ task_unlock(current);
+ return 0;
+}
- if (flags &
- ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED))
- return -EINVAL;
+/* If the policy has additional node information to retrieve, return it */
+static long do_get_policy_node(struct mempolicy *pol)
+{
+ /*
+ * For MPOL_INTERLEAVE, the extended node information is the next
+ * node that will be selected for interleave. For weighted interleave
+ * we return the next node based on the current weight.
+ */
+ if (pol == current->mempolicy && pol->mode == MPOL_INTERLEAVE)
+ return next_node_in(current->il_prev, pol->nodes);
- if (flags & MPOL_F_MEMS_ALLOWED) {
- if (flags & (MPOL_F_NODE|MPOL_F_ADDR))
- return -EINVAL;
- *policy = 0; /* just so it's initialized */
+ if (pol == current->mempolicy &&
+ pol->mode == MPOL_WEIGHTED_INTERLEAVE) {
+ if (pol->wil.cur_weight)
+ return current->il_prev;
+ else
+ return next_node_in(current->il_prev, pol->nodes);
+ }
+ return -EINVAL;
+}
+
+/* Handle user_nodemask condition when fetching nodemask for userspace */
+static void do_get_mempolicy_nodemask(struct mempolicy *pol, nodemask_t *nmask)
+{
+ if (mpol_store_user_nodemask(pol)) {
+ *nmask = pol->w.user_nodemask;
+ } else {
task_lock(current);
- *nmask = cpuset_current_mems_allowed;
+ get_policy_nodemask(pol, nmask);
task_unlock(current);
- return 0;
}
+}
- if (flags & MPOL_F_ADDR) {
- pgoff_t ilx; /* ignored here */
- /*
- * Do NOT fall back to task policy if the
- * vma/shared policy at addr is NULL. We
- * want to return MPOL_DEFAULT in this case.
- */
- mmap_read_lock(mm);
- vma = vma_lookup(mm, addr);
- if (!vma) {
- mmap_read_unlock(mm);
- return -EFAULT;
- }
- pol = __get_vma_policy(vma, addr, &ilx);
- } else if (addr)
- return -EINVAL;
+/* Retrieve NUMA policy for a VMA assocated with a given address */
+static long do_get_vma_mempolicy(unsigned long addr, int *addr_node,
+ struct mempolicy_args *args)
+{
+ pgoff_t ilx;
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma = NULL;
+ struct mempolicy *pol = NULL;
+ mmap_read_lock(mm);
+ vma = vma_lookup(mm, addr);
+ if (!vma) {
+ mmap_read_unlock(mm);
+ return -EFAULT;
+ }
+ pol = __get_vma_policy(vma, addr, &ilx);
if (!pol)
- pol = &default_policy; /* indicates default behavior */
+ pol = &default_policy;
+ else
+ mpol_get(pol);
+ mmap_read_unlock(mm);
- if (flags & MPOL_F_NODE) {
- if (flags & MPOL_F_ADDR) {
- /*
- * Take a refcount on the mpol, because we are about to
- * drop the mmap_lock, after which only "pol" remains
- * valid, "vma" is stale.
- */
- pol_refcount = pol;
- vma = NULL;
- mpol_get(pol);
- mmap_read_unlock(mm);
- err = lookup_node(mm, addr);
- if (err < 0)
- goto out;
- *policy = err;
- } else if (pol == current->mempolicy &&
- pol->mode == MPOL_INTERLEAVE) {
- *policy = next_node_in(current->il_prev, pol->nodes);
- } else if (pol == current->mempolicy &&
- (pol->mode == MPOL_WEIGHTED_INTERLEAVE)) {
- if (pol->wil.cur_weight)
- *policy = current->il_prev;
- else
- *policy = next_node_in(current->il_prev,
- pol->nodes);
- } else {
- err = -EINVAL;
- goto out;
- }
- } else {
- *policy = pol == &default_policy ? MPOL_DEFAULT :
- pol->mode;
- /*
- * Internal mempolicy flags must be masked off before exposing
- * the policy to userspace.
- */
- *policy |= (pol->flags & MPOL_MODE_FLAGS);
- }
+ /* Fetch the node for the given address */
+ if (addr_node)
+ *addr_node = lookup_node(mm, addr);
- err = 0;
- if (nmask) {
- if (mpol_store_user_nodemask(pol)) {
- *nmask = pol->w.user_nodemask;
- } else {
- task_lock(current);
- get_policy_nodemask(pol, nmask);
- task_unlock(current);
- }
+ args->mode = pol == &default_policy ? MPOL_DEFAULT : pol->mode;
+ args->mode_flags = (pol->flags & MPOL_MODE_FLAGS);
+ args->home_node = pol->home_node;
+
+ /* If this policy has extra node info, fetch that */
+ args->policy_node = do_get_policy_node(pol);
+
+ if (args->policy_nodes)
+ do_get_mempolicy_nodemask(pol, args->policy_nodes);
+
+ if (pol != &default_policy) {
+ mpol_put(pol);
+ mpol_cond_put(pol);
}
- out:
- mpol_cond_put(pol);
- if (vma)
- mmap_read_unlock(mm);
- if (pol_refcount)
- mpol_put(pol_refcount);
- return err;
+ return 0;
+}
+
+/* Retrieve NUMA policy for the current task */
+static long do_get_task_mempolicy(struct mempolicy_args *args)
+{
+ struct mempolicy *pol = current->mempolicy;
+
+ if (!pol)
+ pol = &default_policy; /* indicates default behavior */
+
+ args->mode = pol == &default_policy ? MPOL_DEFAULT : pol->mode;
+ /* Internal flags must be masked off before exposing to userspace */
+ args->mode_flags = (pol->flags & MPOL_MODE_FLAGS);
+ args->home_node = NUMA_NO_NODE;
+
+ args->policy_node = do_get_policy_node(pol);
+
+ if (args->policy_nodes)
+ do_get_mempolicy_nodemask(pol, args->policy_nodes);
+
+ return 0;
}
#ifdef CONFIG_MIGRATION
@@ -1731,16 +1736,76 @@ static int kernel_get_mempolicy(int __user *policy,
unsigned long addr,
unsigned long flags)
{
+ struct mempolicy_args args;
int err;
- int pval;
+ int address_node = NUMA_NO_NODE;
+ int pval = 0;
nodemask_t nodes;
if (nmask != NULL && maxnode < nr_node_ids)
return -EINVAL;
- addr = untagged_addr(addr);
+ if (flags &
+ ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED))
+ return -EINVAL;
- err = do_get_mempolicy(&pval, &nodes, addr, flags);
+ /* Ensure any data that may be copied to userland is initialized */
+ memset(&args, 0, sizeof(args));
+ args.policy_nodes = &nodes;
+
+ /*
+ * set_mempolicy was originally multiplexed based on 3 flags:
+ * MPOL_F_MEMS_ALLOWED: fetch task->mems_allowed
+ * MPOL_F_ADDR : operate on vma->mempolicy
+ * MPOL_F_NODE : change return value of *policy
+ *
+ * Split this behavior out here, rather than internal functions,
+ * so that the internal functions can be re-used by future
+ * get_mempolicy2 interfaces and the arg structure made extensible
+ */
+ if (flags & MPOL_F_MEMS_ALLOWED) {
+ if (flags & (MPOL_F_NODE|MPOL_F_ADDR))
+ return -EINVAL;
+ pval = 0; /* just so it's initialized */
+ err = do_get_mems_allowed(&nodes);
+ } else if (flags & MPOL_F_ADDR) {
+ /* If F_ADDR, we operation on a vma policy (or default) */
+ err = do_get_vma_mempolicy(untagged_addr(addr),
+ &address_node, &args);
+ if (err)
+ return err;
+ /* if (F_ADDR | F_NODE), *pval is the address' node */
+ if (flags & MPOL_F_NODE) {
+ /* if we failed to fetch, that's likely an EFAULT */
+ if (address_node < 0)
+ return address_node;
+ pval = address_node;
+ } else
+ pval = args.mode | args.mode_flags;
+ } else {
+ /* if not F_ADDR and addr != null, EINVAL */
+ if (addr)
+ return -EINVAL;
+
+ err = do_get_task_mempolicy(&args);
+ if (err)
+ return err;
+ /*
+ * if F_NODE was set and mode was MPOL_INTERLEAVE
+ * *pval is equal to next interleave node.
+ *
+ * if args.policy_node < 0, this means the mode did
+ * not have a policy. This presently emulates the
+ * original behavior of (F_NODE) & (!MPOL_INTERLEAVE)
+ * producing -EINVAL
+ */
+ if (flags & MPOL_F_NODE) {
+ if (args.policy_node < 0)
+ return args.policy_node;
+ pval = args.policy_node;
+ } else
+ pval = args.mode | args.mode_flags;
+ }
if (err)
return err;
--
2.39.1
This patch adds the plumbing into mpol_new() to allow the argument
structure's home_node field to be set during mempolicy creation.
The syscall sys_set_mempolicy_home_node was added to allow a home
node to be registered for a vma.
For set_mempolicy2 and mbind2 syscalls, it would be useful to add
this as an extension to allow the user to submit a fully formed
mempolicy configuration in a single call, rather than require
multiple calls to configure a mempolicy.
This will become particularly useful if/when pidfd interfaces to
change process mempolicies from outside the task appear, as each
call to change the mempolicy does an atomic swap of that policy
in the task, rather than mutate the policy.
Signed-off-by: Gregory Price <[email protected]>
---
mm/mempolicy.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 4426365a353d..fe340480e296 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -306,7 +306,7 @@ static struct mempolicy *mpol_new(struct mempolicy_args *args)
atomic_set(&policy->refcnt, 1);
policy->mode = mode;
policy->flags = flags;
- policy->home_node = NUMA_NO_NODE;
+ policy->home_node = args->home_node;
policy->wil.cur_weight = 0;
return policy;
@@ -1625,6 +1625,7 @@ static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask,
args.mode = lmode;
args.mode_flags = mode_flags;
args.policy_nodes = &nodes;
+ args.home_node = NUMA_NO_NODE;
return do_set_mempolicy(&args);
}
@@ -2985,6 +2986,8 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
margs.mode = mpol->mode;
margs.mode_flags = mpol->flags;
margs.policy_nodes = &mpol->w.user_nodemask;
+ margs.home_node = NUMA_NO_NODE;
+
/* contextualize the tmpfs mount point mempolicy to this file */
npol = mpol_new(&margs);
if (IS_ERR(npol))
@@ -3143,6 +3146,7 @@ void __init numa_policy_init(void)
memset(&args, 0, sizeof(args));
args.mode = MPOL_INTERLEAVE;
args.policy_nodes = &interleave_nodes;
+ args.home_node = NUMA_NO_NODE;
if (do_set_mempolicy(&args))
pr_err("%s: interleaving failed\n", __func__);
@@ -3157,6 +3161,7 @@ void numa_default_policy(void)
memset(&args, 0, sizeof(args));
args.mode = MPOL_DEFAULT;
+ args.home_node = NUMA_NO_NODE;
do_set_mempolicy(&args);
}
@@ -3279,6 +3284,8 @@ int mpol_parse_str(char *str, struct mempolicy **mpol)
margs.mode = mode;
margs.mode_flags = mode_flags;
margs.policy_nodes = &nodes;
+ margs.home_node = NUMA_NO_NODE;
+
new = mpol_new(&margs);
if (IS_ERR(new))
goto out;
--
2.39.1
This patch adds the new user-api argument structure intended for
set_mempolicy2 and mbind2.
struct mpol_args {
__u16 mode;
__u16 mode_flags;
__s32 home_node; /* mbind2: policy home node */
__aligned_u64 *pol_nodes;
__u64 pol_maxnodes;
__s32 policy_node; /* get_mempolicy: policy node info */
};
This structure is intended to be extensible as new mempolicy extensions
are added.
For example, set_mempolicy_home_node was added to allow vma mempolicies
to have a preferred/home node assigned. This structure allows the
addition of that setting at the time the mempolicy is set, rather
than requiring additional calls to modify the policy.
Full breakdown of arguments as of this patch:
mode: Mempolicy mode (MPOL_DEFAULT, MPOL_INTERLEAVE)
mode_flags: Flags previously or'd into mode in set_mempolicy
(e.g.: MPOL_F_STATIC_NODES, MPOL_F_RELATIVE_NODES)
home_node: for mbind2. Allows the setting of a policy's home
with the use of MPOL_MF_HOME_NODE
pol_nodes: Policy nodemask
pol_maxnodes: Max number of nodes in the policy nodemask
policy_node: for get_mempolicy2. Returns extended information
about a policy that was previously reported by
passing MPOL_F_NODE to get_mempolicy. Instead of
overriding the mode value, simply add a field.
Suggested-by: Frank van der Linden <[email protected]>
Suggested-by: Vinicius Tavares Petrucci <[email protected]>
Suggested-by: Hasan Al Maruf <[email protected]>
Signed-off-by: Gregory Price <[email protected]>
Co-developed-by: Vinicius Tavares Petrucci <[email protected]>
Signed-off-by: Vinicius Tavares Petrucci <[email protected]>
---
.../admin-guide/mm/numa_memory_policy.rst | 18 ++++++++++++++++++
include/linux/syscalls.h | 1 +
include/uapi/linux/mempolicy.h | 10 ++++++++++
3 files changed, 29 insertions(+)
diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst
index d2c8e712785b..d5fcebdd7996 100644
--- a/Documentation/admin-guide/mm/numa_memory_policy.rst
+++ b/Documentation/admin-guide/mm/numa_memory_policy.rst
@@ -482,6 +482,24 @@ closest to which page allocation will come from. Specifying the home node overri
the default allocation policy to allocate memory close to the local node for an
executing CPU.
+Extended Mempolicy Arguments::
+
+ struct mpol_args {
+ __u16 mode;
+ __u16 mode_flags;
+ __s32 home_node; /* mbind2: policy home node */
+ __aligned_u64 pol_nodes; /* nodemask pointer */
+ __u64 pol_maxnodes;
+ __s32 policy_node; /* get_mempolicy2: policy node information */
+ };
+
+The extended mempolicy argument structure is defined to allow the mempolicy
+interfaces future extensibility without the need for additional system calls.
+
+The core arguments (mode, mode_flags, pol_nodes, and pol_maxnodes) apply to
+all interfaces relative to their non-extended counterparts. Each additional
+field may only apply to specific extended interfaces. See the respective
+extended interface man page for more details.
Memory Policy Command Line Interface
====================================
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index fd9d12de7e92..a52395ca3f00 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -74,6 +74,7 @@ struct landlock_ruleset_attr;
enum landlock_rule_type;
struct cachestat_range;
struct cachestat;
+struct mpol_args;
#include <linux/types.h>
#include <linux/aio_abi.h>
diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h
index 1f9bb10d1a47..c06f2afa7fe3 100644
--- a/include/uapi/linux/mempolicy.h
+++ b/include/uapi/linux/mempolicy.h
@@ -27,6 +27,16 @@ enum {
MPOL_MAX, /* always last member of enum */
};
+struct mpol_args {
+ /* Basic mempolicy settings */
+ __u16 mode;
+ __u16 mode_flags;
+ __s32 home_node; /* mbind2: policy home node */
+ __aligned_u64 pol_nodes;
+ __u64 pol_maxnodes;
+ __s32 policy_node; /* get_mempolicy: policy node info */
+};
+
/* Flags for set_mempolicy */
#define MPOL_F_STATIC_NODES (1 << 15)
#define MPOL_F_RELATIVE_NODES (1 << 14)
--
2.39.1
set_mempolicy2 is an extensible set_mempolicy interface which allows
a user to set the per-task memory policy.
Defined as:
set_mempolicy2(struct mpol_args *args, size_t size, unsigned long flags);
relevant mpol_args fields include the following:
mode: The MPOL_* policy (DEFAULT, INTERLEAVE, etc.)
mode_flags: The MPOL_F_* flags that were previously passed in or'd
into the mode. This was split to hopefully allow future
extensions additional mode/flag space.
pol_nodes: the nodemask to apply for the memory policy
pol_maxnodes: The max number of nodes described by pol_nodes
The usize arg is intended for the user to pass in sizeof(mpol_args)
to allow forward/backward compatibility whenever possible.
The flags argument is intended to future proof the syscall against
future extensions which may require interpreting the arguments in
the structure differently.
Semantics of `set_mempolicy` are otherwise the same as `set_mempolicy`
as of this patch.
Suggested-by: Michal Hocko <[email protected]>
Signed-off-by: Gregory Price <[email protected]>
---
.../admin-guide/mm/numa_memory_policy.rst | 10 ++++++
arch/alpha/kernel/syscalls/syscall.tbl | 1 +
arch/arm/tools/syscall.tbl | 1 +
arch/arm64/include/asm/unistd.h | 2 +-
arch/arm64/include/asm/unistd32.h | 2 ++
arch/m68k/kernel/syscalls/syscall.tbl | 1 +
arch/microblaze/kernel/syscalls/syscall.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n32.tbl | 1 +
arch/mips/kernel/syscalls/syscall_o32.tbl | 1 +
arch/parisc/kernel/syscalls/syscall.tbl | 1 +
arch/powerpc/kernel/syscalls/syscall.tbl | 1 +
arch/s390/kernel/syscalls/syscall.tbl | 1 +
arch/sh/kernel/syscalls/syscall.tbl | 1 +
arch/sparc/kernel/syscalls/syscall.tbl | 1 +
arch/x86/entry/syscalls/syscall_32.tbl | 1 +
arch/x86/entry/syscalls/syscall_64.tbl | 1 +
arch/xtensa/kernel/syscalls/syscall.tbl | 1 +
include/linux/syscalls.h | 2 ++
include/uapi/asm-generic/unistd.h | 4 ++-
kernel/sys_ni.c | 1 +
mm/mempolicy.c | 36 +++++++++++++++++++
.../arch/mips/entry/syscalls/syscall_n64.tbl | 1 +
.../arch/powerpc/entry/syscalls/syscall.tbl | 1 +
.../perf/arch/s390/entry/syscalls/syscall.tbl | 1 +
.../arch/x86/entry/syscalls/syscall_64.tbl | 1 +
25 files changed, 73 insertions(+), 2 deletions(-)
diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst
index d5fcebdd7996..e57d400d0281 100644
--- a/Documentation/admin-guide/mm/numa_memory_policy.rst
+++ b/Documentation/admin-guide/mm/numa_memory_policy.rst
@@ -432,6 +432,8 @@ Set [Task] Memory Policy::
long set_mempolicy(int mode, const unsigned long *nmask,
unsigned long maxnode);
+ long set_mempolicy2(struct mpol_args args, size_t size,
+ unsigned long flags);
Set's the calling task's "task/process memory policy" to mode
specified by the 'mode' argument and the set of nodes defined by
@@ -440,6 +442,12 @@ specified by the 'mode' argument and the set of nodes defined by
'mode' argument with the flag (for example: MPOL_INTERLEAVE |
MPOL_F_STATIC_NODES).
+set_mempolicy2() is an extended version of set_mempolicy() capable
+of setting a mempolicy which requires more information than can be
+passed via get_mempolicy(). For example, weighted interleave with
+task-local weights requires a weight array to be passed via the
+'mpol_args->il_weights' argument in the 'struct mpol_args' arg.
+
See the set_mempolicy(2) man page for more details
@@ -496,6 +504,8 @@ Extended Mempolicy Arguments::
The extended mempolicy argument structure is defined to allow the mempolicy
interfaces future extensibility without the need for additional system calls.
+Extended interfaces (set_mempolicy2) use this argument structure.
+
The core arguments (mode, mode_flags, pol_nodes, and pol_maxnodes) apply to
all interfaces relative to their non-extended counterparts. Each additional
field may only apply to specific extended interfaces. See the respective
diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index 18c842ca6c32..0dc288a1118a 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl
@@ -496,3 +496,4 @@
564 common futex_wake sys_futex_wake
565 common futex_wait sys_futex_wait
566 common futex_requeue sys_futex_requeue
+567 common set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index 584f9528c996..50172ec0e1f5 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -470,3 +470,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index 531effca5f1f..298313d2e0af 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -39,7 +39,7 @@
#define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5)
#define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800)
-#define __NR_compat_syscalls 457
+#define __NR_compat_syscalls 458
#endif
#define __ARCH_WANT_SYS_CLONE
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index 9f7c1bf99526..cee8d669c342 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -919,6 +919,8 @@ __SYSCALL(__NR_futex_wake, sys_futex_wake)
__SYSCALL(__NR_futex_wait, sys_futex_wait)
#define __NR_futex_requeue 456
__SYSCALL(__NR_futex_requeue, sys_futex_requeue)
+#define __NR_set_mempolicy2 457
+__SYSCALL(__NR_set_mempolicy2, sys_set_mempolicy2)
/*
* Please add new compat syscalls above this comment and update
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index 7a4b780e82cb..839d90c535f2 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl
@@ -456,3 +456,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index 5b6a0b02b7de..567c8b883735 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -462,3 +462,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index a842b41c8e06..cc0640e16f2f 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -395,3 +395,4 @@
454 n32 futex_wake sys_futex_wake
455 n32 futex_wait sys_futex_wait
456 n32 futex_requeue sys_futex_requeue
+457 n32 set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index 525cc54bc63b..f7262fde98d9 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -444,3 +444,4 @@
454 o32 futex_wake sys_futex_wake
455 o32 futex_wait sys_futex_wait
456 o32 futex_requeue sys_futex_requeue
+457 o32 set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index a47798fed54e..e10f0e8bd064 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -455,3 +455,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index 7fab411378f2..4f03f5f42b78 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -543,3 +543,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index 86fec9b080f6..f98dadc2e9df 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -459,3 +459,4 @@
454 common futex_wake sys_futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index 363fae0fe9bf..f47ba9f2d05d 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl
@@ -459,3 +459,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index 7bcaa3d5ea44..53fb16616728 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl
@@ -502,3 +502,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index c8fac5205803..4b4dc41b24ee 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -461,3 +461,4 @@
454 i386 futex_wake sys_futex_wake
455 i386 futex_wait sys_futex_wait
456 i386 futex_requeue sys_futex_requeue
+457 i386 set_mempolicy2 sys_set_mempolicy2
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 8cb8bf68721c..1bc2190bec27 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -378,6 +378,7 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
#
# Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index 06eefa9c1458..e26dc89399eb 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -427,3 +427,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index a52395ca3f00..451f0089601f 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -823,6 +823,8 @@ asmlinkage long sys_get_mempolicy(int __user *policy,
unsigned long addr, unsigned long flags);
asmlinkage long sys_set_mempolicy(int mode, const unsigned long __user *nmask,
unsigned long maxnode);
+asmlinkage long sys_set_mempolicy2(struct mpol_args __user *args, size_t size,
+ unsigned long flags);
asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
const unsigned long __user *from,
const unsigned long __user *to);
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 756b013fb832..55486aba099f 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -828,9 +828,11 @@ __SYSCALL(__NR_futex_wake, sys_futex_wake)
__SYSCALL(__NR_futex_wait, sys_futex_wait)
#define __NR_futex_requeue 456
__SYSCALL(__NR_futex_requeue, sys_futex_requeue)
+#define __NR_set_mempolicy2 457
+__SYSCALL(__NR_set_mempolicy2, sys_set_mempolicy2)
#undef __NR_syscalls
-#define __NR_syscalls 457
+#define __NR_syscalls 458
/*
* 32 bit systems traditionally used different
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index e1a6e3c675c0..7d6eb0eec056 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -189,6 +189,7 @@ COND_SYSCALL(remap_file_pages);
COND_SYSCALL(mbind);
COND_SYSCALL(get_mempolicy);
COND_SYSCALL(set_mempolicy);
+COND_SYSCALL(set_mempolicy2);
COND_SYSCALL(migrate_pages);
COND_SYSCALL(move_pages);
COND_SYSCALL(set_mempolicy_home_node);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index fe340480e296..eb296ed507e6 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1636,6 +1636,42 @@ SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask,
return kernel_set_mempolicy(mode, nmask, maxnode);
}
+SYSCALL_DEFINE3(set_mempolicy2, struct mpol_args __user *, uargs, size_t, usize,
+ unsigned long, flags)
+{
+ struct mpol_args kargs;
+ struct mempolicy_args margs;
+ int err;
+ nodemask_t policy_nodemask;
+ unsigned long __user *nodes_ptr;
+
+ if (flags)
+ return -EINVAL;
+
+ err = copy_struct_from_user(&kargs, sizeof(kargs), uargs, usize);
+ if (err)
+ return err;
+
+ err = validate_mpol_flags(kargs.mode, &kargs.mode_flags);
+ if (err)
+ return err;
+
+ memset(&margs, 0, sizeof(margs));
+ margs.mode = kargs.mode;
+ margs.mode_flags = kargs.mode_flags;
+ if (kargs.pol_nodes) {
+ nodes_ptr = u64_to_user_ptr(kargs.pol_nodes);
+ err = get_nodes(&policy_nodemask, nodes_ptr,
+ kargs.pol_maxnodes);
+ if (err)
+ return err;
+ margs.policy_nodes = &policy_nodemask;
+ } else
+ margs.policy_nodes = NULL;
+
+ return do_set_mempolicy(&margs);
+}
+
static int kernel_migrate_pages(pid_t pid, unsigned long maxnode,
const unsigned long __user *old_nodes,
const unsigned long __user *new_nodes)
diff --git a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
index 116ff501bf92..bb1351df51d9 100644
--- a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
+++ b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
@@ -371,3 +371,4 @@
454 n64 futex_wake sys_futex_wake
455 n64 futex_wait sys_futex_wait
456 n64 futex_requeue sys_futex_requeue
+457 n64 set_mempolicy2 sys_set_mempolicy2
diff --git a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
index 7fab411378f2..4f03f5f42b78 100644
--- a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
@@ -543,3 +543,4 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
index 86fec9b080f6..f98dadc2e9df 100644
--- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
@@ -459,3 +459,4 @@
454 common futex_wake sys_futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2 sys_set_mempolicy2
diff --git a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
index 8cb8bf68721c..21f2579679d4 100644
--- a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
@@ -378,6 +378,7 @@
454 common futex_wake sys_futex_wake
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
+457 common set_mempolicy2 sys_set_mempolicy2
#
# Due to a historical design error, certain syscalls are numbered differently
--
2.39.1
get_mempolicy2 is an extensible get_mempolicy interface which allows
a user to retrieve the memory policy for a task or address.
Defined as:
get_mempolicy2(struct mpol_args *args, size_t size,
unsigned long addr, unsigned long flags)
Top level input values:
mpol_args: The field which collects information about the mempolicy
returned to userspace.
addr: if MPOL_F_ADDR is passed in `flags`, this address will be
used to return the mempolicy details of the vma the
address belongs to
flags: if MPOL_F_ADDR, return mempolicy info vma containing addr
else, returns task mempolicy information
Input values include the following fields of mpol_args:
pol_nodes: if set, the nodemask of the policy returned here
pol_maxnodes: if pol_nodes is set, must describe max number of nodes
to be copied to pol_nodes
Output values include the following fields of mpol_args:
mode: mempolicy mode
mode_flags: mempolicy mode flags
home_node: policy home node will be returned here, or -1 if not.
pol_nodes: if set, the nodemask for the mempolicy
policy_node: if the policy has extended node information, it will
be placed here. For example MPOL_INTERLEAVE will
return the next node which will be used for allocation
MPOL_F_NODE has been dropped from get_mempolicy2 (EINVAL).
Suggested-by: Michal Hocko <[email protected]>
Signed-off-by: Gregory Price <[email protected]>
---
.../admin-guide/mm/numa_memory_policy.rst | 10 ++++-
arch/alpha/kernel/syscalls/syscall.tbl | 1 +
arch/arm/tools/syscall.tbl | 1 +
arch/arm64/include/asm/unistd.h | 2 +-
arch/arm64/include/asm/unistd32.h | 2 +
arch/m68k/kernel/syscalls/syscall.tbl | 1 +
arch/microblaze/kernel/syscalls/syscall.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n32.tbl | 1 +
arch/mips/kernel/syscalls/syscall_o32.tbl | 1 +
arch/parisc/kernel/syscalls/syscall.tbl | 1 +
arch/powerpc/kernel/syscalls/syscall.tbl | 1 +
arch/s390/kernel/syscalls/syscall.tbl | 1 +
arch/sh/kernel/syscalls/syscall.tbl | 1 +
arch/sparc/kernel/syscalls/syscall.tbl | 1 +
arch/x86/entry/syscalls/syscall_32.tbl | 1 +
arch/x86/entry/syscalls/syscall_64.tbl | 1 +
arch/xtensa/kernel/syscalls/syscall.tbl | 1 +
include/linux/syscalls.h | 2 +
include/uapi/asm-generic/unistd.h | 4 +-
kernel/sys_ni.c | 1 +
mm/mempolicy.c | 43 +++++++++++++++++++
.../arch/mips/entry/syscalls/syscall_n64.tbl | 1 +
.../arch/powerpc/entry/syscalls/syscall.tbl | 1 +
.../perf/arch/s390/entry/syscalls/syscall.tbl | 1 +
.../arch/x86/entry/syscalls/syscall_64.tbl | 1 +
25 files changed, 79 insertions(+), 3 deletions(-)
diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst
index e57d400d0281..8c1fcdb30602 100644
--- a/Documentation/admin-guide/mm/numa_memory_policy.rst
+++ b/Documentation/admin-guide/mm/numa_memory_policy.rst
@@ -456,11 +456,19 @@ Get [Task] Memory Policy or Related Information::
long get_mempolicy(int *mode,
const unsigned long *nmask, unsigned long maxnode,
void *addr, int flags);
+ long get_mempolicy2(struct mpol_args args, size_t size,
+ unsigned long addr, unsigned long flags);
Queries the "task/process memory policy" of the calling task, or the
policy or location of a specified virtual address, depending on the
'flags' argument.
+get_mempolicy2() is an extended version of get_mempolicy() capable of
+acquiring extended information about a mempolicy, including those
+that can only be set via set_mempolicy2() or mbind2().
+
+MPOL_F_NODE functionality has been removed from get_mempolicy2().
+
See the get_mempolicy(2) man page for more details
@@ -504,7 +512,7 @@ Extended Mempolicy Arguments::
The extended mempolicy argument structure is defined to allow the mempolicy
interfaces future extensibility without the need for additional system calls.
-Extended interfaces (set_mempolicy2) use this argument structure.
+Extended interfaces (set_mempolicy2 and get_mempolicy2) use this structure.
The core arguments (mode, mode_flags, pol_nodes, and pol_maxnodes) apply to
all interfaces relative to their non-extended counterparts. Each additional
diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index 0dc288a1118a..0301a8b0a262 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl
@@ -497,3 +497,4 @@
565 common futex_wait sys_futex_wait
566 common futex_requeue sys_futex_requeue
567 common set_mempolicy2 sys_set_mempolicy2
+568 common get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index 50172ec0e1f5..771a33446e8e 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -471,3 +471,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index 298313d2e0af..b63f870debaf 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -39,7 +39,7 @@
#define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5)
#define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800)
-#define __NR_compat_syscalls 458
+#define __NR_compat_syscalls 459
#endif
#define __ARCH_WANT_SYS_CLONE
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index cee8d669c342..f8d01007aee0 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -921,6 +921,8 @@ __SYSCALL(__NR_futex_wait, sys_futex_wait)
__SYSCALL(__NR_futex_requeue, sys_futex_requeue)
#define __NR_set_mempolicy2 457
__SYSCALL(__NR_set_mempolicy2, sys_set_mempolicy2)
+#define __NR_get_mempolicy2 458
+__SYSCALL(__NR_get_mempolicy2, sys_get_mempolicy2)
/*
* Please add new compat syscalls above this comment and update
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index 839d90c535f2..048a409e684c 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl
@@ -457,3 +457,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index 567c8b883735..327b01bd6793 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -463,3 +463,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index cc0640e16f2f..921d58e1da23 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -396,3 +396,4 @@
455 n32 futex_wait sys_futex_wait
456 n32 futex_requeue sys_futex_requeue
457 n32 set_mempolicy2 sys_set_mempolicy2
+458 n32 get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index f7262fde98d9..9271c83c9993 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -445,3 +445,4 @@
455 o32 futex_wait sys_futex_wait
456 o32 futex_requeue sys_futex_requeue
457 o32 set_mempolicy2 sys_set_mempolicy2
+458 o32 get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index e10f0e8bd064..0654f3f89fc7 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -456,3 +456,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index 4f03f5f42b78..ac11d2064e7a 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -544,3 +544,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index f98dadc2e9df..1cdcafe1ccca 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -460,3 +460,4 @@
455 common futex_wait sys_futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index f47ba9f2d05d..f71742024c29 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl
@@ -460,3 +460,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index 53fb16616728..2fbf5dbe0620 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl
@@ -503,3 +503,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 4b4dc41b24ee..0af813b9a118 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -462,3 +462,4 @@
455 i386 futex_wait sys_futex_wait
456 i386 futex_requeue sys_futex_requeue
457 i386 set_mempolicy2 sys_set_mempolicy2
+458 i386 get_mempolicy2 sys_get_mempolicy2
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 1bc2190bec27..0b777876fc15 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -379,6 +379,7 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
#
# Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index e26dc89399eb..4536c9a4227d 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -428,3 +428,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 451f0089601f..f696855cbe8c 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -821,6 +821,8 @@ asmlinkage long sys_get_mempolicy(int __user *policy,
unsigned long __user *nmask,
unsigned long maxnode,
unsigned long addr, unsigned long flags);
+asmlinkage long sys_get_mempolicy2(struct mpol_args __user *args, size_t size,
+ unsigned long addr, unsigned long flags);
asmlinkage long sys_set_mempolicy(int mode, const unsigned long __user *nmask,
unsigned long maxnode);
asmlinkage long sys_set_mempolicy2(struct mpol_args __user *args, size_t size,
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 55486aba099f..719accc731db 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -830,9 +830,11 @@ __SYSCALL(__NR_futex_wait, sys_futex_wait)
__SYSCALL(__NR_futex_requeue, sys_futex_requeue)
#define __NR_set_mempolicy2 457
__SYSCALL(__NR_set_mempolicy2, sys_set_mempolicy2)
+#define __NR_get_mempolicy2 458
+__SYSCALL(__NR_get_mempolicy2, sys_get_mempolicy2)
#undef __NR_syscalls
-#define __NR_syscalls 458
+#define __NR_syscalls 459
/*
* 32 bit systems traditionally used different
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 7d6eb0eec056..e4883eaa4e61 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -188,6 +188,7 @@ COND_SYSCALL(process_mrelease);
COND_SYSCALL(remap_file_pages);
COND_SYSCALL(mbind);
COND_SYSCALL(get_mempolicy);
+COND_SYSCALL(get_mempolicy2);
COND_SYSCALL(set_mempolicy);
COND_SYSCALL(set_mempolicy2);
COND_SYSCALL(migrate_pages);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index eb296ed507e6..ebb08261d7cb 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1863,6 +1863,49 @@ SYSCALL_DEFINE5(get_mempolicy, int __user *, policy,
return kernel_get_mempolicy(policy, nmask, maxnode, addr, flags);
}
+SYSCALL_DEFINE4(get_mempolicy2, struct mpol_args __user *, uargs, size_t, usize,
+ unsigned long, addr, unsigned long, flags)
+{
+ struct mpol_args kargs;
+ struct mempolicy_args margs;
+ int err;
+ nodemask_t policy_nodemask;
+ unsigned long __user *nodes_ptr;
+
+ if (flags & ~(MPOL_F_ADDR))
+ return -EINVAL;
+
+ /* initialize any memory liable to be copied to userland */
+ memset(&margs, 0, sizeof(margs));
+
+ err = copy_struct_from_user(&kargs, sizeof(kargs), uargs, usize);
+ if (err)
+ return -EINVAL;
+
+ margs.policy_nodes = kargs.pol_nodes ? &policy_nodemask : NULL;
+ if (flags & MPOL_F_ADDR)
+ err = do_get_vma_mempolicy(untagged_addr(addr), NULL, &margs);
+ else
+ err = do_get_task_mempolicy(&margs);
+
+ if (err)
+ return err;
+
+ kargs.mode = margs.mode;
+ kargs.mode_flags = margs.mode_flags;
+ kargs.policy_node = margs.policy_node;
+ kargs.home_node = margs.home_node;
+ if (kargs.pol_nodes) {
+ nodes_ptr = u64_to_user_ptr(kargs.pol_nodes);
+ err = copy_nodes_to_user(nodes_ptr, kargs.pol_maxnodes,
+ margs.policy_nodes);
+ if (err)
+ return err;
+ }
+
+ return copy_to_user(uargs, &kargs, usize) ? -EFAULT : 0;
+}
+
bool vma_migratable(struct vm_area_struct *vma)
{
if (vma->vm_flags & (VM_IO | VM_PFNMAP))
diff --git a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
index bb1351df51d9..c34c6877379e 100644
--- a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
+++ b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
@@ -372,3 +372,4 @@
455 n64 futex_wait sys_futex_wait
456 n64 futex_requeue sys_futex_requeue
457 n64 set_mempolicy2 sys_set_mempolicy2
+458 n64 get_mempolicy2 sys_get_mempolicy2
diff --git a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
index 4f03f5f42b78..ac11d2064e7a 100644
--- a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
@@ -544,3 +544,4 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
index f98dadc2e9df..1cdcafe1ccca 100644
--- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
@@ -460,3 +460,4 @@
455 common futex_wait sys_futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2 sys_get_mempolicy2
diff --git a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
index 21f2579679d4..edf338f32645 100644
--- a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
@@ -379,6 +379,7 @@
455 common futex_wait sys_futex_wait
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
+458 common get_mempolicy2 sys_get_mempolicy2
#
# Due to a historical design error, certain syscalls are numbered differently
--
2.39.1
mbind2 is an extensible mbind interface which allows a user to
set the mempolicy for one or more address ranges.
Defined as:
mbind2(unsigned long addr, unsigned long len, struct mpol_args *args,
size_t size, unsigned long flags)
addr: address of the memory range to operate on
len: length of the memory range
flags: MPOL_MF_HOME_NODE + original mbind() flags
Input values include the following fields of mpol_args:
mode: The MPOL_* policy (DEFAULT, INTERLEAVE, etc.)
mode_flags: The MPOL_F_* flags that were previously passed in or'd
into the mode. This was split to hopefully allow future
extensions additional mode/flag space.
pol_nodes: the nodemask to apply for the memory policy
pol_maxnodes: The max number of nodes described by pol_nodes
home_node: if MPOL_MF_HOME_NODE, set home node of policy to this
otherwise it is ignored.
The semantics are otherwise the same as mbind(), except that
the home_node can be set.
Suggested-by: Michal Hocko <[email protected]>
Suggested-by: Frank van der Linden <[email protected]>
Suggested-by: Vinicius Tavares Petrucci <[email protected]>
Suggested-by: Rakie Kim <[email protected]>
Suggested-by: Hyeongtak Ji <[email protected]>
Suggested-by: Honggyu Kim <[email protected]>
Signed-off-by: Gregory Price <[email protected]>
Co-developed-by: Vinicius Tavares Petrucci <[email protected]>
---
.../admin-guide/mm/numa_memory_policy.rst | 12 +++++-
arch/alpha/kernel/syscalls/syscall.tbl | 1 +
arch/arm/tools/syscall.tbl | 1 +
arch/arm64/include/asm/unistd.h | 2 +-
arch/arm64/include/asm/unistd32.h | 2 +
arch/m68k/kernel/syscalls/syscall.tbl | 1 +
arch/microblaze/kernel/syscalls/syscall.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n32.tbl | 1 +
arch/mips/kernel/syscalls/syscall_o32.tbl | 1 +
arch/parisc/kernel/syscalls/syscall.tbl | 1 +
arch/powerpc/kernel/syscalls/syscall.tbl | 1 +
arch/s390/kernel/syscalls/syscall.tbl | 1 +
arch/sh/kernel/syscalls/syscall.tbl | 1 +
arch/sparc/kernel/syscalls/syscall.tbl | 1 +
arch/x86/entry/syscalls/syscall_32.tbl | 1 +
arch/x86/entry/syscalls/syscall_64.tbl | 1 +
arch/xtensa/kernel/syscalls/syscall.tbl | 1 +
include/linux/syscalls.h | 3 ++
include/uapi/asm-generic/unistd.h | 4 +-
include/uapi/linux/mempolicy.h | 5 ++-
kernel/sys_ni.c | 1 +
mm/mempolicy.c | 43 +++++++++++++++++++
.../arch/mips/entry/syscalls/syscall_n64.tbl | 1 +
.../arch/powerpc/entry/syscalls/syscall.tbl | 1 +
.../perf/arch/s390/entry/syscalls/syscall.tbl | 1 +
.../arch/x86/entry/syscalls/syscall_64.tbl | 1 +
26 files changed, 85 insertions(+), 5 deletions(-)
diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst
index 8c1fcdb30602..99e1f732cade 100644
--- a/Documentation/admin-guide/mm/numa_memory_policy.rst
+++ b/Documentation/admin-guide/mm/numa_memory_policy.rst
@@ -477,12 +477,18 @@ Install VMA/Shared Policy for a Range of Task's Address Space::
long mbind(void *start, unsigned long len, int mode,
const unsigned long *nmask, unsigned long maxnode,
unsigned flags);
+ long mbind2(void* start, unsigned long len, struct mpol_args args,
+ size_t size, unsigned long flags);
mbind() installs the policy specified by (mode, nmask, maxnodes) as a
VMA policy for the range of the calling task's address space specified
by the 'start' and 'len' arguments. Additional actions may be
requested via the 'flags' argument.
+mbind2() is an extended version of mbind() capable of setting extended
+mempolicy features. For example, one can set the home node for the memory
+policy without an additional call to set_mempolicy_home_node().
+
See the mbind(2) man page for more details.
Set home node for a Range of Task's Address Spacec::
@@ -498,6 +504,9 @@ closest to which page allocation will come from. Specifying the home node overri
the default allocation policy to allocate memory close to the local node for an
executing CPU.
+mbind2() also provides a way for the home node to be set at the time the
+mempolicy is set. See the mbind(2) man page for more details.
+
Extended Mempolicy Arguments::
struct mpol_args {
@@ -512,7 +521,8 @@ Extended Mempolicy Arguments::
The extended mempolicy argument structure is defined to allow the mempolicy
interfaces future extensibility without the need for additional system calls.
-Extended interfaces (set_mempolicy2 and get_mempolicy2) use this structure.
+Extended interfaces (set_mempolicy2, get_mempolicy2, and mbind2) use this
+this argument structure.
The core arguments (mode, mode_flags, pol_nodes, and pol_maxnodes) apply to
all interfaces relative to their non-extended counterparts. Each additional
diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index 0301a8b0a262..e8239293c35a 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl
@@ -498,3 +498,4 @@
566 common futex_requeue sys_futex_requeue
567 common set_mempolicy2 sys_set_mempolicy2
568 common get_mempolicy2 sys_get_mempolicy2
+569 common mbind2 sys_mbind2
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index 771a33446e8e..a3f39750257a 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -472,3 +472,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index b63f870debaf..abe10a833fcd 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -39,7 +39,7 @@
#define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5)
#define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800)
-#define __NR_compat_syscalls 459
+#define __NR_compat_syscalls 460
#endif
#define __ARCH_WANT_SYS_CLONE
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index f8d01007aee0..89aaae33b81f 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -923,6 +923,8 @@ __SYSCALL(__NR_futex_requeue, sys_futex_requeue)
__SYSCALL(__NR_set_mempolicy2, sys_set_mempolicy2)
#define __NR_get_mempolicy2 458
__SYSCALL(__NR_get_mempolicy2, sys_get_mempolicy2)
+#define __NR_get_mbind2 459
+__SYSCALL(__NR_get_mbind2, sys_get_mbind2)
/*
* Please add new compat syscalls above this comment and update
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index 048a409e684c..9a12dface18e 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl
@@ -458,3 +458,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index 327b01bd6793..6cb740123137 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -464,3 +464,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index 921d58e1da23..52cf720f8ae2 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -397,3 +397,4 @@
456 n32 futex_requeue sys_futex_requeue
457 n32 set_mempolicy2 sys_set_mempolicy2
458 n32 get_mempolicy2 sys_get_mempolicy2
+459 n32 mbind2 sys_mbind2
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index 9271c83c9993..fd37c5301a48 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -446,3 +446,4 @@
456 o32 futex_requeue sys_futex_requeue
457 o32 set_mempolicy2 sys_set_mempolicy2
458 o32 get_mempolicy2 sys_get_mempolicy2
+459 o32 mbind2 sys_mbind2
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index 0654f3f89fc7..fcd67bc405b1 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -457,3 +457,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index ac11d2064e7a..89715417014c 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -545,3 +545,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index 1cdcafe1ccca..c8304e0d0aa7 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -461,3 +461,4 @@
456 common futex_requeue sys_futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2 sys_mbind2
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index f71742024c29..e5c51b6c367f 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl
@@ -461,3 +461,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index 2fbf5dbe0620..74527f585500 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl
@@ -504,3 +504,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 0af813b9a118..be2e2aa17dd8 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -463,3 +463,4 @@
456 i386 futex_requeue sys_futex_requeue
457 i386 set_mempolicy2 sys_set_mempolicy2
458 i386 get_mempolicy2 sys_get_mempolicy2
+459 i386 mbind2 sys_mbind2
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 0b777876fc15..6e2347eb8773 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -380,6 +380,7 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
#
# Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index 4536c9a4227d..f00a21317dc0 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -429,3 +429,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index f696855cbe8c..b42622ea9ed9 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -817,6 +817,9 @@ asmlinkage long sys_mbind(unsigned long start, unsigned long len,
const unsigned long __user *nmask,
unsigned long maxnode,
unsigned flags);
+asmlinkage long sys_mbind2(unsigned long start, unsigned long len,
+ const struct mpol_args __user *uargs, size_t usize,
+ unsigned long flags);
asmlinkage long sys_get_mempolicy(int __user *policy,
unsigned long __user *nmask,
unsigned long maxnode,
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 719accc731db..cd31599bb9cc 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -832,9 +832,11 @@ __SYSCALL(__NR_futex_requeue, sys_futex_requeue)
__SYSCALL(__NR_set_mempolicy2, sys_set_mempolicy2)
#define __NR_get_mempolicy2 458
__SYSCALL(__NR_get_mempolicy2, sys_get_mempolicy2)
+#define __NR_mbind2 459
+__SYSCALL(__NR_mbind2, sys_mbind2)
#undef __NR_syscalls
-#define __NR_syscalls 459
+#define __NR_syscalls 460
/*
* 32 bit systems traditionally used different
diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h
index c06f2afa7fe3..ec1402dae35b 100644
--- a/include/uapi/linux/mempolicy.h
+++ b/include/uapi/linux/mempolicy.h
@@ -54,13 +54,14 @@ struct mpol_args {
#define MPOL_F_ADDR (1<<1) /* look up vma using address */
#define MPOL_F_MEMS_ALLOWED (1<<2) /* return allowed memories */
-/* Flags for mbind */
+/* Flags for mbind/mbind2 */
#define MPOL_MF_STRICT (1<<0) /* Verify existing pages in the mapping */
#define MPOL_MF_MOVE (1<<1) /* Move pages owned by this process to conform
to policy */
#define MPOL_MF_MOVE_ALL (1<<2) /* Move every page to conform to policy */
#define MPOL_MF_LAZY (1<<3) /* UNSUPPORTED FLAG: Lazy migrate on fault */
-#define MPOL_MF_INTERNAL (1<<4) /* Internal flags start here */
+#define MPOL_MF_HOME_NODE (1<<4) /* mbind2: set home node */
+#define MPOL_MF_INTERNAL (1<<5) /* Internal flags start here */
#define MPOL_MF_VALID (MPOL_MF_STRICT | \
MPOL_MF_MOVE | \
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index e4883eaa4e61..5239c2e94e37 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -187,6 +187,7 @@ COND_SYSCALL(process_madvise);
COND_SYSCALL(process_mrelease);
COND_SYSCALL(remap_file_pages);
COND_SYSCALL(mbind);
+COND_SYSCALL(mbind2);
COND_SYSCALL(get_mempolicy);
COND_SYSCALL(get_mempolicy2);
COND_SYSCALL(set_mempolicy);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index ebb08261d7cb..0882fa4aa516 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1603,6 +1603,49 @@ SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len,
return kernel_mbind(start, len, mode, nmask, maxnode, flags);
}
+SYSCALL_DEFINE5(mbind2, unsigned long, start, unsigned long, len,
+ const struct mpol_args __user *, uargs, size_t, usize,
+ unsigned long, flags)
+{
+ struct mpol_args kargs;
+ struct mempolicy_args margs;
+ nodemask_t policy_nodes;
+ unsigned long __user *nodes_ptr;
+ int err;
+
+ if (!start || !len)
+ return -EINVAL;
+
+ err = copy_struct_from_user(&kargs, sizeof(kargs), uargs, usize);
+ if (err)
+ return -EINVAL;
+
+ err = validate_mpol_flags(kargs.mode, &kargs.mode_flags);
+ if (err)
+ return err;
+
+ margs.mode = kargs.mode;
+ margs.mode_flags = kargs.mode_flags;
+
+ /* if home node given, validate it is online */
+ if (flags & MPOL_MF_HOME_NODE) {
+ if ((kargs.home_node >= MAX_NUMNODES) ||
+ !node_online(kargs.home_node))
+ return -EINVAL;
+ margs.home_node = kargs.home_node;
+ } else
+ margs.home_node = NUMA_NO_NODE;
+ flags &= ~MPOL_MF_HOME_NODE;
+
+ nodes_ptr = u64_to_user_ptr(kargs.pol_nodes);
+ err = get_nodes(&policy_nodes, nodes_ptr, kargs.pol_maxnodes);
+ if (err)
+ return err;
+ margs.policy_nodes = &policy_nodes;
+
+ return do_mbind(untagged_addr(start), len, &margs, flags);
+}
+
/* Set the process memory policy */
static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask,
unsigned long maxnode)
diff --git a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
index c34c6877379e..4fd9f742d903 100644
--- a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
+++ b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
@@ -373,3 +373,4 @@
456 n64 futex_requeue sys_futex_requeue
457 n64 set_mempolicy2 sys_set_mempolicy2
458 n64 get_mempolicy2 sys_get_mempolicy2
+459 n64 mbind2 sys_mbind2
diff --git a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
index ac11d2064e7a..89715417014c 100644
--- a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
@@ -545,3 +545,4 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
index 1cdcafe1ccca..c8304e0d0aa7 100644
--- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
@@ -461,3 +461,4 @@
456 common futex_requeue sys_futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2 sys_mbind2
diff --git a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
index edf338f32645..3fc74241da5d 100644
--- a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
@@ -380,6 +380,7 @@
456 common futex_requeue sys_futex_requeue
457 common set_mempolicy2 sys_set_mempolicy2
458 common get_mempolicy2 sys_get_mempolicy2
+459 common mbind2 sys_mbind2
#
# Due to a historical design error, certain syscalls are numbered differently
--
2.39.1
Extend set_mempolicy2 and mbind2 to support weighted interleave, and
demonstrate the extensibility of the mpol_args structure.
To support weighted interleave we add interleave weight fields to the
following structures:
Kernel Internal: (include/linux/mempolicy.h)
struct mempolicy {
/* task-local weights to apply to weighted interleave */
unsigned char weights[MAX_NUMNODES];
}
struct mempolicy_args {
/* Optional: interleave weights for MPOL_WEIGHTED_INTERLEAVE */
unsigned char *il_weights; /* of size MAX_NUMNODES */
}
UAPI: (/include/uapi/linux/mempolicy.h)
struct mpol_args {
/* Optional: interleave weights for MPOL_WEIGHTED_INTERLEAVE */
unsigned char *il_weights; /* of size pol_max_nodes */
}
The task-local weights are a single, one-dimensional array of weights
that apply to all possible nodes on the system. If a node is set in
the mempolicy nodemask, the weight in `il_weights` must be >= 1,
otherwise set_mempolicy2() will return -EINVAL. If a node is not
set in pol_nodemask, the weight will default to `1` in the task policy.
The default value of `1` is required to handle the situation where a
task migrates to a set of nodes for which weights were not set (up to
and including the local numa node). For example, a migrated task whose
nodemask changes entirely will have all its weights defaulted back
to `1`, or if the nodemask changes to include a mix of nodes that
were not previously accounted for - the weighted interleave may be
suboptimal.
If migrations are expected, a task should prefer not to use task-local
interleave weights, and instead utilize the global settings for natural
re-weighting on migration.
To support global vs local weighting, we add the kernel-internal flag:
MPOL_F_GWEIGHT (1 << 5) /* Utilize global weights */
This flag is set when il_weights is omitted by set_mempolicy2(), or
when MPOL_WEIGHTED_INTERLEAVE is set by set_mempolicy(). This internal
mode_flag dictates whether global weights or task-local weights are
utilized by the the various weighted interleave functions:
* weighted_interleave_nodes
* weighted_interleave_nid
* alloc_pages_bulk_array_weighted_interleave
if (pol->flags & MPOL_F_GWEIGHT)
pol_weights = iw_table;
else
pol_weights = pol->wil.weights;
To simplify creations and duplication of mempolicies, the weights are
added as a structure directly within mempolicy. This allows the
existing logic in __mpol_dup to copy the weights without additional
allocations:
if (old == current->mempolicy) {
task_lock(current);
*new = *old;
task_unlock(current);
} else
*new = *old
Suggested-by: Rakie Kim <[email protected]>
Suggested-by: Hyeongtak Ji <[email protected]>
Suggested-by: Honggyu Kim <[email protected]>
Suggested-by: Vinicius Tavares Petrucci <[email protected]>
Signed-off-by: Gregory Price <[email protected]>
Co-developed-by: Rakie Kim <[email protected]>
Signed-off-by: Rakie Kim <[email protected]>
Co-developed-by: Hyeongtak Ji <[email protected]>
Signed-off-by: Hyeongtak Ji <[email protected]>
Co-developed-by: Honggyu Kim <[email protected]>
Signed-off-by: Honggyu Kim <[email protected]>
Co-developed-by: Vinicius Tavares Petrucci <[email protected]>
Signed-off-by: Vinicius Tavares Petrucci <[email protected]>
---
.../admin-guide/mm/numa_memory_policy.rst | 10 ++
include/linux/mempolicy.h | 2 +
include/uapi/linux/mempolicy.h | 2 +
mm/mempolicy.c | 129 +++++++++++++++++-
4 files changed, 139 insertions(+), 4 deletions(-)
diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst
index 99e1f732cade..0e91efe9e769 100644
--- a/Documentation/admin-guide/mm/numa_memory_policy.rst
+++ b/Documentation/admin-guide/mm/numa_memory_policy.rst
@@ -254,6 +254,8 @@ MPOL_WEIGHTED_INTERLEAVE
This mode operates the same as MPOL_INTERLEAVE, except that
interleaving behavior is executed based on weights set in
/sys/kernel/mm/mempolicy/weighted_interleave/
+ when configured to utilize global weights, or based on task-local
+ weights configured with set_mempolicy2(2) or mbind2(2).
Weighted interleave allocations pages on nodes according to
their weight. For example if nodes [0,1] are weighted [5,2]
@@ -261,6 +263,13 @@ MPOL_WEIGHTED_INTERLEAVE
2 pages allocated on node1. This can better distribute data
according to bandwidth on heterogeneous memory systems.
+ When utilizing task-local weights, weights are not rebalanced
+ in the event of a task migration. If a weight has not been
+ explicitly set for a node set in the new nodemask, the
+ value of that weight defaults to "1". For this reason, if
+ migrations are expected or possible, users should consider
+ utilizing global interleave weights.
+
NUMA memory policy supports the following optional mode flags:
MPOL_F_STATIC_NODES
@@ -514,6 +523,7 @@ Extended Mempolicy Arguments::
__u16 mode_flags;
__s32 home_node; /* mbind2: policy home node */
__aligned_u64 pol_nodes; /* nodemask pointer */
+ __aligned_u64 il_weights; /* u8 buf of size pol_maxnodes */
__u64 pol_maxnodes;
__s32 policy_node; /* get_mempolicy2: policy node information */
};
diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index aeac19dfc2b6..387c5c418a66 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -58,6 +58,7 @@ struct mempolicy {
/* Weighted interleave settings */
struct {
unsigned char cur_weight;
+ unsigned char weights[MAX_NUMNODES];
} wil;
};
@@ -70,6 +71,7 @@ struct mempolicy_args {
unsigned short mode_flags; /* policy mode flags */
int home_node; /* mbind: use MPOL_MF_HOME_NODE */
nodemask_t *policy_nodes; /* get/set/mbind */
+ unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
int policy_node; /* get: policy node information */
};
diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h
index ec1402dae35b..16fedf966166 100644
--- a/include/uapi/linux/mempolicy.h
+++ b/include/uapi/linux/mempolicy.h
@@ -33,6 +33,7 @@ struct mpol_args {
__u16 mode_flags;
__s32 home_node; /* mbind2: policy home node */
__aligned_u64 pol_nodes;
+ __aligned_u64 il_weights; /* size: pol_maxnodes * sizeof(char) */
__u64 pol_maxnodes;
__s32 policy_node; /* get_mempolicy: policy node info */
};
@@ -75,6 +76,7 @@ struct mpol_args {
#define MPOL_F_SHARED (1 << 0) /* identify shared policies */
#define MPOL_F_MOF (1 << 3) /* this policy wants migrate on fault */
#define MPOL_F_MORON (1 << 4) /* Migrate On protnone Reference On Node */
+#define MPOL_F_GWEIGHT (1 << 5) /* Utilize global weights */
/*
* These bit locations are exposed in the vm.zone_reclaim_mode sysctl
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 0882fa4aa516..1d73ad29e36c 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -271,6 +271,7 @@ static struct mempolicy *mpol_new(struct mempolicy_args *args)
unsigned short mode = args->mode;
unsigned short flags = args->mode_flags;
nodemask_t *nodes = args->policy_nodes;
+ int node;
if (mode == MPOL_DEFAULT) {
if (nodes && !nodes_empty(*nodes))
@@ -297,6 +298,19 @@ static struct mempolicy *mpol_new(struct mempolicy_args *args)
(flags & MPOL_F_STATIC_NODES) ||
(flags & MPOL_F_RELATIVE_NODES))
return ERR_PTR(-EINVAL);
+ } else if (mode == MPOL_WEIGHTED_INTERLEAVE) {
+ /* weighted interleave requires a nodemask and weights > 0 */
+ if (nodes_empty(*nodes))
+ return ERR_PTR(-EINVAL);
+ if (args->il_weights) {
+ node = first_node(*nodes);
+ while (node != MAX_NUMNODES) {
+ if (!args->il_weights[node])
+ return ERR_PTR(-EINVAL);
+ node = next_node(node, *nodes);
+ }
+ } else if (!(args->mode_flags & MPOL_F_GWEIGHT))
+ return ERR_PTR(-EINVAL);
} else if (nodes_empty(*nodes))
return ERR_PTR(-EINVAL);
@@ -309,6 +323,17 @@ static struct mempolicy *mpol_new(struct mempolicy_args *args)
policy->home_node = args->home_node;
policy->wil.cur_weight = 0;
+ if (policy->mode == MPOL_WEIGHTED_INTERLEAVE && args->il_weights) {
+ policy->wil.cur_weight = 0;
+ /* Minimum weight value is always 1 */
+ memset(policy->wil.weights, 1, MAX_NUMNODES);
+ node = first_node(*nodes);
+ while (node != MAX_NUMNODES) {
+ policy->wil.weights[node] = args->il_weights[node];
+ node = next_node(node, *nodes);
+ }
+ }
+
return policy;
}
@@ -937,6 +962,17 @@ static void do_get_mempolicy_nodemask(struct mempolicy *pol, nodemask_t *nmask)
}
}
+static void do_get_mempolicy_il_weights(struct mempolicy *pol,
+ unsigned char weights[MAX_NUMNODES])
+{
+ if (pol->mode != MPOL_WEIGHTED_INTERLEAVE)
+ memset(weights, 0, MAX_NUMNODES);
+ else if (pol->flags & MPOL_F_GWEIGHT)
+ memcpy(weights, iw_table, MAX_NUMNODES);
+ else
+ memcpy(weights, pol->wil.weights, MAX_NUMNODES);
+}
+
/* Retrieve NUMA policy for a VMA assocated with a given address */
static long do_get_vma_mempolicy(unsigned long addr, int *addr_node,
struct mempolicy_args *args)
@@ -973,6 +1009,9 @@ static long do_get_vma_mempolicy(unsigned long addr, int *addr_node,
if (args->policy_nodes)
do_get_mempolicy_nodemask(pol, args->policy_nodes);
+ if (args->il_weights)
+ do_get_mempolicy_il_weights(pol, args->il_weights);
+
if (pol != &default_policy) {
mpol_put(pol);
mpol_cond_put(pol);
@@ -999,6 +1038,9 @@ static long do_get_task_mempolicy(struct mempolicy_args *args)
if (args->policy_nodes)
do_get_mempolicy_nodemask(pol, args->policy_nodes);
+ if (args->il_weights)
+ do_get_mempolicy_il_weights(pol, args->il_weights);
+
return 0;
}
@@ -1521,6 +1563,9 @@ static long kernel_mbind(unsigned long start, unsigned long len,
if (err)
return err;
+ if (mode & MPOL_WEIGHTED_INTERLEAVE)
+ mode_flags |= MPOL_F_GWEIGHT;
+
memset(&margs, 0, sizeof(margs));
margs.mode = lmode;
margs.mode_flags = mode_flags;
@@ -1611,6 +1656,8 @@ SYSCALL_DEFINE5(mbind2, unsigned long, start, unsigned long, len,
struct mempolicy_args margs;
nodemask_t policy_nodes;
unsigned long __user *nodes_ptr;
+ unsigned char weights[MAX_NUMNODES];
+ unsigned char __user *weights_ptr;
int err;
if (!start || !len)
@@ -1643,6 +1690,23 @@ SYSCALL_DEFINE5(mbind2, unsigned long, start, unsigned long, len,
return err;
margs.policy_nodes = &policy_nodes;
+ if (kargs.mode == MPOL_WEIGHTED_INTERLEAVE) {
+ weights_ptr = u64_to_user_ptr(kargs.il_weights);
+ if (weights_ptr) {
+ err = copy_struct_from_user(weights,
+ sizeof(weights),
+ weights_ptr,
+ kargs.pol_maxnodes);
+ if (err)
+ return err;
+ margs.il_weights = weights;
+ } else {
+ margs.il_weights = NULL;
+ margs.mode_flags |= MPOL_F_GWEIGHT;
+ }
+ } else
+ margs.il_weights = NULL;
+
return do_mbind(untagged_addr(start), len, &margs, flags);
}
@@ -1664,6 +1728,9 @@ static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask,
if (err)
return err;
+ if (mode & MPOL_WEIGHTED_INTERLEAVE)
+ mode_flags |= MPOL_F_GWEIGHT;
+
memset(&args, 0, sizeof(args));
args.mode = lmode;
args.mode_flags = mode_flags;
@@ -1687,6 +1754,8 @@ SYSCALL_DEFINE3(set_mempolicy2, struct mpol_args __user *, uargs, size_t, usize,
int err;
nodemask_t policy_nodemask;
unsigned long __user *nodes_ptr;
+ unsigned char weights[MAX_NUMNODES];
+ unsigned char __user *weights_ptr;
if (flags)
return -EINVAL;
@@ -1712,6 +1781,20 @@ SYSCALL_DEFINE3(set_mempolicy2, struct mpol_args __user *, uargs, size_t, usize,
} else
margs.policy_nodes = NULL;
+ if (kargs.mode == MPOL_WEIGHTED_INTERLEAVE && kargs.il_weights) {
+ weights_ptr = u64_to_user_ptr(kargs.il_weights);
+ err = copy_struct_from_user(weights,
+ sizeof(weights),
+ weights_ptr,
+ kargs.pol_maxnodes);
+ if (err)
+ return err;
+ margs.il_weights = weights;
+ } else {
+ margs.il_weights = NULL;
+ margs.mode_flags |= MPOL_F_GWEIGHT;
+ }
+
return do_set_mempolicy(&margs);
}
@@ -1914,17 +1997,25 @@ SYSCALL_DEFINE4(get_mempolicy2, struct mpol_args __user *, uargs, size_t, usize,
int err;
nodemask_t policy_nodemask;
unsigned long __user *nodes_ptr;
+ unsigned char __user *weights_ptr;
+ unsigned char weights[MAX_NUMNODES];
if (flags & ~(MPOL_F_ADDR))
return -EINVAL;
/* initialize any memory liable to be copied to userland */
memset(&margs, 0, sizeof(margs));
+ memset(weights, 0, sizeof(weights));
err = copy_struct_from_user(&kargs, sizeof(kargs), uargs, usize);
if (err)
return -EINVAL;
+ if (kargs.il_weights)
+ margs.il_weights = weights;
+ else
+ margs.il_weights = NULL;
+
margs.policy_nodes = kargs.pol_nodes ? &policy_nodemask : NULL;
if (flags & MPOL_F_ADDR)
err = do_get_vma_mempolicy(untagged_addr(addr), NULL, &margs);
@@ -1946,6 +2037,13 @@ SYSCALL_DEFINE4(get_mempolicy2, struct mpol_args __user *, uargs, size_t, usize,
return err;
}
+ if (kargs.mode == MPOL_WEIGHTED_INTERLEAVE && kargs.il_weights) {
+ weights_ptr = u64_to_user_ptr(kargs.il_weights);
+ err = copy_to_user(weights_ptr, weights, kargs.pol_maxnodes);
+ if (err)
+ return err;
+ }
+
return copy_to_user(uargs, &kargs, usize) ? -EFAULT : 0;
}
@@ -2062,13 +2160,18 @@ static unsigned int weighted_interleave_nodes(struct mempolicy *policy)
{
unsigned int next;
struct task_struct *me = current;
+ unsigned char next_weight;
next = next_node_in(me->il_prev, policy->nodes);
if (next == MAX_NUMNODES)
return next;
- if (!policy->wil.cur_weight)
- policy->wil.cur_weight = iw_table[next];
+ if (!policy->wil.cur_weight) {
+ next_weight = (policy->flags & MPOL_F_GWEIGHT) ?
+ iw_table[next] :
+ policy->wil.weights[next];
+ policy->wil.cur_weight = next_weight ? next_weight : 1;
+ }
policy->wil.cur_weight--;
if (!policy->wil.cur_weight)
@@ -2142,6 +2245,7 @@ static unsigned int weighted_interleave_nid(struct mempolicy *pol, pgoff_t ilx)
nodemask_t nodemask = pol->nodes;
unsigned int target, weight_total = 0;
int nid;
+ unsigned char *pol_weights;
unsigned char weights[MAX_NUMNODES];
unsigned char weight;
@@ -2153,8 +2257,13 @@ static unsigned int weighted_interleave_nid(struct mempolicy *pol, pgoff_t ilx)
return nid;
/* Then collect weights on stack and calculate totals */
+ if (pol->flags & MPOL_F_GWEIGHT)
+ pol_weights = iw_table;
+ else
+ pol_weights = pol->wil.weights;
+
for_each_node_mask(nid, nodemask) {
- weight = iw_table[nid];
+ weight = pol_weights[nid];
weight_total += weight;
weights[nid] = weight;
}
@@ -2552,6 +2661,7 @@ static unsigned long alloc_pages_bulk_array_weighted_interleave(gfp_t gfp,
unsigned long nr_allocated;
unsigned long rounds;
unsigned long node_pages, delta;
+ unsigned char *pol_weights;
unsigned char weight;
unsigned char weights[MAX_NUMNODES];
unsigned int weight_total = 0;
@@ -2565,9 +2675,14 @@ static unsigned long alloc_pages_bulk_array_weighted_interleave(gfp_t gfp,
nnodes = nodes_weight(nodes);
+ if (pol->flags & MPOL_F_GWEIGHT)
+ pol_weights = iw_table;
+ else
+ pol_weights = pol->wil.weights;
+
/* Collect weights and save them on stack so they don't change */
for_each_node_mask(node, nodes) {
- weight = iw_table[node];
+ weight = pol_weights[node];
weight_total += weight;
weights[node] = weight;
}
@@ -3092,6 +3207,7 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
{
int ret;
struct mempolicy_args margs;
+ unsigned char weights[MAX_NUMNODES];
sp->root = RB_ROOT; /* empty tree == default mempolicy */
rwlock_init(&sp->lock);
@@ -3109,6 +3225,11 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
margs.mode_flags = mpol->flags;
margs.policy_nodes = &mpol->w.user_nodemask;
margs.home_node = NUMA_NO_NODE;
+ if (margs.mode == MPOL_WEIGHTED_INTERLEAVE &&
+ !(margs.mode_flags & MPOL_F_GWEIGHT)) {
+ memcpy(weights, mpol->wil.weights, sizeof(weights));
+ margs.il_weights = weights;
+ }
/* contextualize the tmpfs mount point mempolicy to this file */
npol = mpol_new(&margs);
--
2.39.1
Gregory Price <[email protected]> writes:
> This patch set extends the mempolicy interface to enable new
> mempolicies which may require extended data to operate.
>
> MPOL_WEIGHTED_INTERLEAVE is included as an example extension.
Per my understanding, it's better to describe why we need this patchset
at the beginning. Per my understanding, weighted interleave is used to
expand DRAM bandwidth for workloads with real high memory bandwidth
requirements. Without it, DRAM bandwidth will be saturated, which leads
to poor performance.
> Patches 1 and 2 (weighted interleave w/ sysfs globals) can be
> an candidate for merge separate from patches 3-11, but 3-11 are
> dependent on them, so it is included in the overall RFC.
>
> There are 3 major "phases" in the patch set:
>
> 1) Implement MPOL_WEIGHTED_INTERLEAVE with a sysfs extension,
> which allows and admin/daemon to set weights via sysfs.
> (Patches 1 & 2). Weighted interleave allows for interleave
> other than 1:1 (round-robin), such that bandwidth can be used
> optimally. For example, a 9:1 interleave between nodes 0 and 1
> would place 9 pages on node0 for every 1 page on node1.
>
> 2) A refactor of the mempolicy creation mechanism to accept an
> extensible argument structure `struct mempolicy_args` to promote
> code re-use between the original mempolicy/mbind interfaces and
> the new extended mempolicy/mbind interfaces.
> (Patches 3-6)
>
> 3) Implementation of set_mempolicy2, get_mempolicy2, and mbind2,
> along with the addition of task-local weights so that per-task
> weights can be registered for MPOL_WEIGHTED_INTERLEAVE.
> (Patches 7-11)
>
> A sample numactl extension can be found here to test global weights:
> https://github.com/gmprice/numactl/tree/weighted_interleave_master
>
> Additionally, at the bottom of this cover letter is linux test
> project tests for backward and forward compatibility, and some
> sample software for quick and dirty testing.
>
> = Performance summary =
> (tests may have different configurations, see extended info below)
> 1) MLC (W2) : +38% over DRAM. +264% over default interleave.
> MLC (W5) : +40% over DRAM. +226% over default interleave.
> 2) Stream : -6% to +4% over DRAM, +430% over default interleave.
> 3) XSBench : +19% over DRAM. +47% over default interleave.
>
> = LTP Testing Summary =
> https://github.com/gmprice/ltp/tree/mempolicy2
> existing mempolicy & mbind tests: pass
> mempolicy & mbind + weighted interleave (global weights): pass
> mempolicy2 & mbind2 + weighted interleave (global weights): pass
> mempolicy2 & mbind2 + weighted interleave (local weights): pass
>
> = Other test summary =
> numactl global weight useage: pass
> weight distribution validation: pass
>
> = v4 (full notes moved to bottom) =
> - CONFIG_MMU, CONFIG_SYSFS, tools/perf configs
> - sysfs attr init build warning
> - arch/arm64 syscall wire-ups (Thanks Arnd!)
> - Performance tests
>
> =====================================================================
> Performance tests - MLC
> From - Ravi Jonnalagadda <[email protected]>
>
> Hardware: Single-socket, multiple CXL memory expanders.
>
> Workload: W2
> Data Signature: 2:1 read:write
> DRAM only bandwidth (GBps): 298.8
> DRAM + CXL (default interleave) (GBps): 113.04
> DRAM + CXL (weighted interleave)(GBps): 412.5
> Gain over DRAM only: 1.38x
> Gain over default interleave: 2.64x
>
> Workload: W5
> Data Signature: 1:1 read:write
> DRAM only bandwidth (GBps): 273.2
> DRAM + CXL (default interleave) (GBps): 117.23
> DRAM + CXL (weighted interleave)(GBps): 382.7
> Gain over DRAM only: 1.4x
> Gain over default interleave: 2.26x
>
> =====================================================================
> Performance test - Stream
> From - Gregory Price <[email protected]>
>
> Hardware: Single socket, single CXL expander
>
> Summary: 64 threads, ~18GB workload, 3GB per array, executed 100 times
> Default interleave : -78% (slower than DRAM)
> Global weighting : -6% to +4% (workload dependant)
> mbind2 weights : +2.5% to +4% (consistently better than DRAM)
>
> dram only:
> numactl --cpunodebind=1 --membind=1 ./stream_c.exe --ntimes 100 --array-size 400M --malloc
> Function Direction BestRateMBs AvgTime MinTime MaxTime
> Copy: 0->0 200923.2 0.032662 0.031853 0.033301
> Scale: 0->0 202123.0 0.032526 0.031664 0.032970
> Add: 0->0 208873.2 0.047322 0.045961 0.047884
> Triad: 0->0 208523.8 0.047262 0.046038 0.048414
>
> CXL-only:
> numactl --cpunodebind=1 -w --membind=2 ./stream_c.exe --ntimes 100 --array-size 400M --malloc
> Copy: 0->0 22209.7 0.288661 0.288162 0.289342
> Scale: 0->0 22288.2 0.287549 0.287147 0.288291
> Add: 0->0 24419.1 0.393372 0.393135 0.393735
> Triad: 0->0 24484.6 0.392337 0.392083 0.394331
>
> Based on the above, the optimal weights are ~9:1
> echo 9 > /sys/kernel/mm/mempolicy/weighted_interleave/node1
> echo 1 > /sys/kernel/mm/mempolicy/weighted_interleave/node2
>
> default interleave:
> numactl --cpunodebind=1 --interleave=1,2 ./stream_c.exe --ntimes 100 --array-size 400M --malloc
> Copy: 0->0 44666.2 0.143671 0.143285 0.144174
> Scale: 0->0 44781.6 0.143256 0.142916 0.143713
> Add: 0->0 48600.7 0.197719 0.197528 0.197858
> Triad: 0->0 48727.5 0.197204 0.197014 0.197439
>
> global weighted interleave:
> numactl --cpunodebind=1 -w --interleave=1,2 ./stream_c.exe --ntimes 100 --array-size 400M --malloc
> Copy: 0->0 190085.9 0.034289 0.033669 0.034645
> Scale: 0->0 207677.4 0.031909 0.030817 0.033061
> Add: 0->0 202036.8 0.048737 0.047516 0.053409
> Triad: 0->0 217671.5 0.045819 0.044103 0.046755
>
> targted regions w/ global weights (mbind2 on malloc regions special -b flag)
> numactl --cpunodebind=1 --membind=1 ./stream_c.exe -b --ntimes 100 --array-size 400M --malloc
> Copy: 0->0 205827.0 0.031445 0.031094 0.031984
> Scale: 0->0 208171.8 0.031320 0.030744 0.032505
> Add: 0->0 217352.0 0.045087 0.044168 0.046515
> Triad: 0->0 216884.8 0.045062 0.044263 0.046982
>
> =====================================================================
> Performance tests - XSBench
> From - Hyeongtak Ji <[email protected]>
>
> Hardware: Single socket, Single CXL memory Expander
>
> NUMA node 0: 56 logical cores, 128 GB memory
> NUMA node 2: 96 GB CXL memory
> Threads: 56
> Lookups: 170,000,000
>
> Summary: +19% over DRAM. +47% over default interleave.
>
> Performance tests - XSBench
> 1. dram only
> $ numactl -m 0 ./XSBench -s XL –p 5000000
> Runtime: 36.235 seconds
> Lookups/s: 4,691,618
>
> 2. default interleave
> $ numactl –i 0,2 ./XSBench –s XL –p 5000000
> Runtime: 55.243 seconds
> Lookups/s: 3,077,293
>
> 3. weighted interleave
> numactl –w –i 0,2 ./XSBench –s XL –p 5000000
> Runtime: 29.262 seconds
> Lookups/s: 5,809,513
>
> =====================================================================
> (Patch 1) : sysfs addition - /sys/kernel/mm/mempolicy/
>
> This feature provides a way to set interleave weight information under
> sysfs at /sys/kernel/mm/mempolicy/weighted_interleave/
>
> The sysfs structure is designed as follows.
>
> $ tree /sys/kernel/mm/mempolicy/
> /sys/kernel/mm/mempolicy/
> └── weighted_interleave
> ├── nodeN
> └── nodeN+X
>
> 'mempolicy' is added to '/sys/kernel/mm/' as a control group for
> the mempolicy subsystem.
>
> Internally, weights are represented as an array of unsigned char
>
> static unsigned char iw_table[MAX_NUMNODES];
>
> char was chosen as most reasonable distributions can be represented
> as factors <100, and to minimize memory usage (1KB)
>
> We present possible nodes, instead of online nodes, to simplify the
> management interface, considering that a) the table is of size
> MAX_NUMNODES anyway to simplify fetching of weights (no need to track
> sizes, and MAX_NUMNODES is typically at most 1kb), and b) it simplifies
> management of hotplug events, allowing for weights to be set prior to
> a node coming online, which may be beneficial for immediate use.
>
> the 'weight' of a node (an unsigned char of value 1-255) is the number
> of pages that are allocated during a "weighted interleave" round.
> (See 'weighted interleave' for more details').
>
> =====================================================================
> (Patch 2) set_mempolicy: MPOL_WEIGHTED_INTERLEAVE
>
> Weighted interleave is a new memory policy that interleaves memory
> across numa nodes in the provided nodemask based on the weights
> described in patch 1 (sysfs global weights).
>
> When a system has multiple NUMA nodes and it becomes bandwidth hungry,
> the current MPOL_INTERLEAVE could be an wise option.
>
> However, if those NUMA nodes consist of different types of memory such
> as having local DRAM and CXL memory together, the current round-robin
> based interleaving policy doesn't maximize the overall bandwidth
> because of their different bandwidth characteristics.
>
> Instead, the interleaving can be more efficient when the allocation
> policy follows each NUMA nodes' bandwidth weight rather than having 1:1
> round-robin allocation.
>
> This patch introduces a new memory policy, MPOL_WEIGHTED_INTERLEAVE,
> which enables weighted interleaving between NUMA nodes. Weighted
> interleave allows for a proportional distribution of memory across
> multiple numa nodes, preferablly apportioned to match the bandwidth
> capacity of each node from the perspective of the accessing node.
>
> For example, if a system has 1 CPU node (0), and 2 memory nodes (0,1),
> with a relative bandwidth of (100GB/s, 50GB/s) respectively, the
> appropriate weight distribution is (2:1).
>
> Weights will be acquired from the global weight array exposed by the
> sysfs extension: /sys/kernel/mm/mempolicy/weighted_interleave/
>
> The policy will then allocate the number of pages according to the
> set weights. For example, if the weights are (2,1), then 2 pages
> will be allocated on node0 for every 1 page allocated on node1.
>
> The new flag MPOL_WEIGHTED_INTERLEAVE can be used in set_mempolicy(2)
> and mbind(2).
>
> =====================================================================
> (Patches 3-6) Refactoring mempolicy for code-reuse
>
> To avoid multiple paths of mempolicy creation, we should refactor the
> existing code to enable the designed extensibility, and refactor
> existing users to utilize the new interface (while retaining the
> existing userland interface).
>
> This set of patches introduces a new mempolicy_args structure, which
> is used to more fully describe a requested mempolicy - to include
> existing and future extensions.
>
> /*
> * Describes settings of a mempolicy during set/get syscalls and
> * kernel internal calls to do_set_mempolicy()
> */
> struct mempolicy_args {
> unsigned short mode; /* policy mode */
> unsigned short mode_flags; /* policy mode flags */
> int home_node; /* mbind: use MPOL_MF_HOME_NODE */
> nodemask_t *policy_nodes; /* get/set/mbind */
> unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
> int policy_node; /* get: policy node information */
> };
Because we use more and more parameters to describe the mempolicy, I
think it's a good idea to replace some parameters with struct. But I
don't think it's a good idea to put unrelated stuff into the struct.
For example,
struct mempolicy_param {
unsigned short mode; /* policy mode */
unsigned short mode_flags; /* policy mode flags */
int home_node; /* mbind: use MPOL_MF_HOME_NODE */
nodemask_t *policy_nodes;
unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
};
describe the parameters to create the mempolicy. It can be used by
set/get_mempolicy() and mbind(). So, I think that it's a good
abstraction. But "policy_node" has nothing to do with set_mempolicy()
and mbind(). So I think that we shouldn't add it into the struct. It's
totally OK to use different parameters for different functions. For
example,
long do_set_mempolicy(struct mempolicy_param *mparam);
long do_mbind(unsigned long start, unsigned long len,
struct mempolicy_param *mparam, unsigned long flags);
long do_get_task_mempolicy(struct mempolicy_param *mparam, int
*policy_node);
This isn't the full list. My point is to use separate parameter for
something specific for some function.
> This arg structure will eventually be utilized by the following
> interfaces:
> mpol_new() - new mempolicy creation
> do_get_mempolicy() - acquiring information about mempolicy
> do_set_mempolicy() - setting the task mempolicy
> do_mbind() - setting a vma mempolicy
>
> do_get_mempolicy() is completely refactored to break it out into
> separate functionality based on the flags provided by get_mempolicy(2)
> MPOL_F_MEMS_ALLOWED: acquires task->mems_allowed
> MPOL_F_ADDR: acquires information on vma policies
> MPOL_F_NODE: changes the output for the policy arg to node info
>
> We refactor the get_mempolicy syscall flatten the logic based on these
> flags, and aloow for set_mempolicy2() to re-use the underlying logic.
>
> The result of this refactor, and the new mempolicy_args structure, is
> that extensions like 'sys_set_mempolicy_home_node' can now be directly
> integrated into the initial call to 'set_mempolicy2', and that more
> complete information about a mempolicy can be returned with a single
> call to 'get_mempolicy2', rather than multiple calls to 'get_mempolicy'
>
>
> =====================================================================
> (Patches 7-10) set_mempolicy2, get_mempolicy2, mbind2
>
> These interfaces are the 'extended' counterpart to their relatives.
> They use the userland 'struct mpol_args' structure to communicate a
> complete mempolicy configuration to the kernel. This structure
> looks very much like the kernel-internal 'struct mempolicy_args':
>
> struct mpol_args {
> /* Basic mempolicy settings */
> __u16 mode;
> __u16 mode_flags;
> __s32 home_node;
> __aligned_u64 pol_nodes;
> __aligned_u64 *il_weights; /* of size pol_maxnodes */
> __u64 pol_maxnodes;
> __s32 policy_node;
> };
Same as my idea above. I think we shouldn't add policy_node for
set_mempolicy2()/mbind2(). That will make users confusing. We can use
a different struct for get_mempolicy2().
> The basic mempolicy settings which are shared across all interfaces
> are captured at the top of the structure, while extensions such as
> 'policy_node' and 'addr' are collected beneath.
>
> The syscalls are uniform and defined as follows:
>
> long sys_mbind2(unsigned long addr, unsigned long len,
> struct mpol_args *args, size_t usize,
> unsigned long flags);
>
> long sys_get_mempolicy2(struct mpol_args *args, size_t size,
> unsigned long addr, unsigned long flags);
>
> long sys_set_mempolicy2(struct mpol_args *args, size_t size,
> unsigned long flags);
>
> The 'flags' argument for mbind2 is the same as 'mbind', except with
> the addition of MPOL_MF_HOME_NODE to denote whether the 'home_node'
> field should be utilized.
>
> The 'flags' argument for get_mempolicy2 allows for MPOL_F_ADDR to
> allow operating on VMA policies, but MPOL_F_NODE and MPOL_F_MEMS_ALLOWED
> behavior has been omitted, since get_mempolicy() provides this already.
>
> The 'flags' argument is not used by 'set_mempolicy' at this time, but
> may end up allowing the use of MPOL_MF_HOME_NODE if such functionality
> is desired.
>
> The extensions can be summed up as follows:
>
> get_mempolicy2 extensions:
> 'mode' and 'policy_node' can now be fetched with a single call
> rather than multiple with a combination of flags.
> - 'mode' will always return the policy mode
> - 'policy_node' will replace the functionality of MPOL_F_NODE
> - MPOL_F_MEMS_ALLOWED and MPOL_F_NODE are otherwise not supported
>
> set_mempolicy2:
> - task-local interleave weights can be set via 'il_weights'
> (see next patch)
>
> mbind2:
> - 'home_node' field sets policy home node w/ MPOL_MF_HOME_NODE
> - task-local interleave weights can be set via 'il_weights'
> (see next patch)
>
--
Best Regards,
Huang, Ying
[snip]
Gregory Price <[email protected]> writes:
> Extend set_mempolicy2 and mbind2 to support weighted interleave, and
> demonstrate the extensibility of the mpol_args structure.
>
> To support weighted interleave we add interleave weight fields to the
> following structures:
>
> Kernel Internal: (include/linux/mempolicy.h)
> struct mempolicy {
> /* task-local weights to apply to weighted interleave */
> unsigned char weights[MAX_NUMNODES];
> }
> struct mempolicy_args {
> /* Optional: interleave weights for MPOL_WEIGHTED_INTERLEAVE */
> unsigned char *il_weights; /* of size MAX_NUMNODES */
> }
>
> UAPI: (/include/uapi/linux/mempolicy.h)
> struct mpol_args {
> /* Optional: interleave weights for MPOL_WEIGHTED_INTERLEAVE */
> unsigned char *il_weights; /* of size pol_max_nodes */
> }
>
> The task-local weights are a single, one-dimensional array of weights
> that apply to all possible nodes on the system. If a node is set in
> the mempolicy nodemask, the weight in `il_weights` must be >= 1,
> otherwise set_mempolicy2() will return -EINVAL. If a node is not
> set in pol_nodemask, the weight will default to `1` in the task policy.
>
> The default value of `1` is required to handle the situation where a
> task migrates to a set of nodes for which weights were not set (up to
> and including the local numa node). For example, a migrated task whose
> nodemask changes entirely will have all its weights defaulted back
> to `1`, or if the nodemask changes to include a mix of nodes that
> were not previously accounted for - the weighted interleave may be
> suboptimal.
>
> If migrations are expected, a task should prefer not to use task-local
> interleave weights, and instead utilize the global settings for natural
> re-weighting on migration.
>
> To support global vs local weighting, we add the kernel-internal flag:
> MPOL_F_GWEIGHT (1 << 5) /* Utilize global weights */
>
> This flag is set when il_weights is omitted by set_mempolicy2(), or
> when MPOL_WEIGHTED_INTERLEAVE is set by set_mempolicy(). This internal
> mode_flag dictates whether global weights or task-local weights are
> utilized by the the various weighted interleave functions:
>
> * weighted_interleave_nodes
> * weighted_interleave_nid
> * alloc_pages_bulk_array_weighted_interleave
>
> if (pol->flags & MPOL_F_GWEIGHT)
> pol_weights = iw_table;
> else
> pol_weights = pol->wil.weights;
>
> To simplify creations and duplication of mempolicies, the weights are
> added as a structure directly within mempolicy. This allows the
> existing logic in __mpol_dup to copy the weights without additional
> allocations:
>
> if (old == current->mempolicy) {
> task_lock(current);
> *new = *old;
> task_unlock(current);
> } else
> *new = *old
>
> Suggested-by: Rakie Kim <[email protected]>
> Suggested-by: Hyeongtak Ji <[email protected]>
> Suggested-by: Honggyu Kim <[email protected]>
> Suggested-by: Vinicius Tavares Petrucci <[email protected]>
> Signed-off-by: Gregory Price <[email protected]>
> Co-developed-by: Rakie Kim <[email protected]>
> Signed-off-by: Rakie Kim <[email protected]>
> Co-developed-by: Hyeongtak Ji <[email protected]>
> Signed-off-by: Hyeongtak Ji <[email protected]>
> Co-developed-by: Honggyu Kim <[email protected]>
> Signed-off-by: Honggyu Kim <[email protected]>
> Co-developed-by: Vinicius Tavares Petrucci <[email protected]>
> Signed-off-by: Vinicius Tavares Petrucci <[email protected]>
> ---
> .../admin-guide/mm/numa_memory_policy.rst | 10 ++
> include/linux/mempolicy.h | 2 +
> include/uapi/linux/mempolicy.h | 2 +
> mm/mempolicy.c | 129 +++++++++++++++++-
> 4 files changed, 139 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst
> index 99e1f732cade..0e91efe9e769 100644
> --- a/Documentation/admin-guide/mm/numa_memory_policy.rst
> +++ b/Documentation/admin-guide/mm/numa_memory_policy.rst
> @@ -254,6 +254,8 @@ MPOL_WEIGHTED_INTERLEAVE
> This mode operates the same as MPOL_INTERLEAVE, except that
> interleaving behavior is executed based on weights set in
> /sys/kernel/mm/mempolicy/weighted_interleave/
> + when configured to utilize global weights, or based on task-local
> + weights configured with set_mempolicy2(2) or mbind2(2).
>
> Weighted interleave allocations pages on nodes according to
> their weight. For example if nodes [0,1] are weighted [5,2]
> @@ -261,6 +263,13 @@ MPOL_WEIGHTED_INTERLEAVE
> 2 pages allocated on node1. This can better distribute data
> according to bandwidth on heterogeneous memory systems.
>
> + When utilizing task-local weights, weights are not rebalanced
> + in the event of a task migration. If a weight has not been
> + explicitly set for a node set in the new nodemask, the
> + value of that weight defaults to "1". For this reason, if
> + migrations are expected or possible, users should consider
> + utilizing global interleave weights.
> +
> NUMA memory policy supports the following optional mode flags:
>
> MPOL_F_STATIC_NODES
> @@ -514,6 +523,7 @@ Extended Mempolicy Arguments::
> __u16 mode_flags;
> __s32 home_node; /* mbind2: policy home node */
> __aligned_u64 pol_nodes; /* nodemask pointer */
> + __aligned_u64 il_weights; /* u8 buf of size pol_maxnodes */
> __u64 pol_maxnodes;
> __s32 policy_node; /* get_mempolicy2: policy node information */
> };
> diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
> index aeac19dfc2b6..387c5c418a66 100644
> --- a/include/linux/mempolicy.h
> +++ b/include/linux/mempolicy.h
> @@ -58,6 +58,7 @@ struct mempolicy {
> /* Weighted interleave settings */
> struct {
> unsigned char cur_weight;
> + unsigned char weights[MAX_NUMNODES];
> } wil;
> };
>
> @@ -70,6 +71,7 @@ struct mempolicy_args {
> unsigned short mode_flags; /* policy mode flags */
> int home_node; /* mbind: use MPOL_MF_HOME_NODE */
> nodemask_t *policy_nodes; /* get/set/mbind */
> + unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
> int policy_node; /* get: policy node information */
> };
>
> diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h
> index ec1402dae35b..16fedf966166 100644
> --- a/include/uapi/linux/mempolicy.h
> +++ b/include/uapi/linux/mempolicy.h
> @@ -33,6 +33,7 @@ struct mpol_args {
> __u16 mode_flags;
> __s32 home_node; /* mbind2: policy home node */
> __aligned_u64 pol_nodes;
> + __aligned_u64 il_weights; /* size: pol_maxnodes * sizeof(char) */
> __u64 pol_maxnodes;
> __s32 policy_node; /* get_mempolicy: policy node info */
> };
You break the ABI you introduced earlier in the patchset. Although they
are done within a patchset, I don't think that it's a good idea. I
suggest to finalize the ABI in the first place. Otherwise, people check
git log will be confused by ABI broken. This makes it easier to be
reviewed too.
> @@ -75,6 +76,7 @@ struct mpol_args {
> #define MPOL_F_SHARED (1 << 0) /* identify shared policies */
> #define MPOL_F_MOF (1 << 3) /* this policy wants migrate on fault */
> #define MPOL_F_MORON (1 << 4) /* Migrate On protnone Reference On Node */
> +#define MPOL_F_GWEIGHT (1 << 5) /* Utilize global weights */
>
> /*
> * These bit locations are exposed in the vm.zone_reclaim_mode sysctl
--
Best Regards,
Huang, Ying
[snip]
Hi Gregory,
kernel test robot noticed the following build errors:
[auto build test ERROR on perf-tools/perf-tools]
[also build test ERROR on linus/master v6.7-rc6]
[cannot apply to perf-tools-next/perf-tools-next tip/perf/core acme/perf/core next-20231219]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Gregory-Price/mm-mempolicy-implement-the-sysfs-based-weighted_interleave-interface/20231219-074837
base: https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools.git perf-tools
patch link: https://lore.kernel.org/r/20231218194631.21667-11-gregory.price%40memverge.com
patch subject: [PATCH v4 10/11] mm/mempolicy: add the mbind2 syscall
config: arm64-defconfig (https://download.01.org/0day-ci/archive/20231219/[email protected]/config)
compiler: aarch64-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231219/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All errors (new ones prefixed by >>):
>> aarch64-linux-ld: arch/arm64/kernel/sys32.o:(.rodata+0xe58): undefined reference to `__arm64_sys_get_mbind2'
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On Tue, Dec 19, 2023 at 11:04:05AM +0800, Huang, Ying wrote:
> Gregory Price <[email protected]> writes:
>
> > This patch set extends the mempolicy interface to enable new
> > mempolicies which may require extended data to operate.
> >
> > MPOL_WEIGHTED_INTERLEAVE is included as an example extension.
>
> Per my understanding, it's better to describe why we need this patchset
> at the beginning. Per my understanding, weighted interleave is used to
> expand DRAM bandwidth for workloads with real high memory bandwidth
> requirements. Without it, DRAM bandwidth will be saturated, which leads
> to poor performance.
>
Will add more details, thanks.
> > struct mempolicy_args {
> > unsigned short mode; /* policy mode */
> > unsigned short mode_flags; /* policy mode flags */
> > int home_node; /* mbind: use MPOL_MF_HOME_NODE */
> > nodemask_t *policy_nodes; /* get/set/mbind */
> > unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
> > int policy_node; /* get: policy node information */
> > };
>
> Because we use more and more parameters to describe the mempolicy, I
> think it's a good idea to replace some parameters with struct. But I
> don't think it's a good idea to put unrelated stuff into the struct.
> For example,
>
> struct mempolicy_param {
> unsigned short mode; /* policy mode */
> unsigned short mode_flags; /* policy mode flags */
> int home_node; /* mbind: use MPOL_MF_HOME_NODE */
> nodemask_t *policy_nodes;
> unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
> };
>
> describe the parameters to create the mempolicy. It can be used by
> set/get_mempolicy() and mbind(). So, I think that it's a good
> abstraction. But "policy_node" has nothing to do with set_mempolicy()
> and mbind(). So I think that we shouldn't add it into the struct. It's
> totally OK to use different parameters for different functions. For
> example,
>
> long do_set_mempolicy(struct mempolicy_param *mparam);
> long do_mbind(unsigned long start, unsigned long len,
> struct mempolicy_param *mparam, unsigned long flags);
> long do_get_task_mempolicy(struct mempolicy_param *mparam, int
> *policy_node);
>
> This isn't the full list. My point is to use separate parameter for
> something specific for some function.
>
this is the internal structure, but i get the point, we can drop it from
the structure and extend the arg list internally.
I'd originally thought to just remove the policy_node stuff all
together from get_mempolicy2(). Do you prefer to have a separate struct
for set/get interfaces so that the get interface struct can be extended?
All the MPOL_F_NODE "alternate data fetch" mechanisms from
get_mempolicy() feel like more of a wart than a feature. And presently
the only data returned in policy_node is the next allocation node for
interleave. That's not even particularly useful, so I'm of a mind to
remove it.
Assuming we remove policy_node altogether... do we still break up the
set/get interface into separate structures to avoid this in the future?
> > struct mpol_args {
> > /* Basic mempolicy settings */
> > __u16 mode;
> > __u16 mode_flags;
> > __s32 home_node;
> > __aligned_u64 pol_nodes;
> > __aligned_u64 *il_weights; /* of size pol_maxnodes */
> > __u64 pol_maxnodes;
> > __s32 policy_node;
> > };
>
> Same as my idea above. I think we shouldn't add policy_node for
> set_mempolicy2()/mbind2(). That will make users confusing. We can use
> a different struct for get_mempolicy2().
>
See above.
~Gregory
On Tue, Dec 19, 2023 at 11:07:10AM +0800, Huang, Ying wrote:
> Gregory Price <[email protected]> writes:
>
> > diff --git a/include/uapi/linux/mempolicy.h b/include/uapi/linux/mempolicy.h
> > index ec1402dae35b..16fedf966166 100644
> > --- a/include/uapi/linux/mempolicy.h
> > +++ b/include/uapi/linux/mempolicy.h
> > @@ -33,6 +33,7 @@ struct mpol_args {
> > __u16 mode_flags;
> > __s32 home_node; /* mbind2: policy home node */
> > __aligned_u64 pol_nodes;
> > + __aligned_u64 il_weights; /* size: pol_maxnodes * sizeof(char) */
> > __u64 pol_maxnodes;
> > __s32 policy_node; /* get_mempolicy: policy node info */
> > };
>
> You break the ABI you introduced earlier in the patchset. Although they
> are done within a patchset, I don't think that it's a good idea. I
> suggest to finalize the ABI in the first place. Otherwise, people check
> git log will be confused by ABI broken. This makes it easier to be
> reviewed too.
>
This is a result of fixing alignment/holes (suggested by Arnd) and my
not dropping policy_node, which I'd originally planned to do.
I figured that whenever we decided to move forward, mempolicy2 and
mbind2 syscalls would end up squashed into a single commit for the
purpose of ensuring the feature goes in as a whole. I can fix this
though.
~Gregory
Hi Gregory,
kernel test robot noticed the following build errors:
[auto build test ERROR on perf-tools/perf-tools]
[also build test ERROR on linus/master v6.7-rc6]
[cannot apply to perf-tools-next/perf-tools-next tip/perf/core acme/perf/core next-20231219]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Gregory-Price/mm-mempolicy-implement-the-sysfs-based-weighted_interleave-interface/20231219-074837
base: https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools.git perf-tools
patch link: https://lore.kernel.org/r/20231218194631.21667-11-gregory.price%40memverge.com
patch subject: [PATCH v4 10/11] mm/mempolicy: add the mbind2 syscall
config: arm64-randconfig-003-20231219 (https://download.01.org/0day-ci/archive/20231220/[email protected]/config)
compiler: clang version 18.0.0git (https://github.com/llvm/llvm-project 5ac12951b4e9bbfcc5791282d0961ec2b65575e9)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231220/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All errors (new ones prefixed by >>):
>> ld.lld: error: undefined symbol: __arm64_sys_get_mbind2
>>> referenced by sys32.c
>>> arch/arm64/kernel/sys32.o:(compat_sys_call_table) in archive vmlinux.a
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Gregory Price <[email protected]> writes:
> On Tue, Dec 19, 2023 at 11:04:05AM +0800, Huang, Ying wrote:
>> Gregory Price <[email protected]> writes:
>>
>> > This patch set extends the mempolicy interface to enable new
>> > mempolicies which may require extended data to operate.
>> >
>> > MPOL_WEIGHTED_INTERLEAVE is included as an example extension.
>>
>> Per my understanding, it's better to describe why we need this patchset
>> at the beginning. Per my understanding, weighted interleave is used to
>> expand DRAM bandwidth for workloads with real high memory bandwidth
>> requirements. Without it, DRAM bandwidth will be saturated, which leads
>> to poor performance.
>>
>
> Will add more details, thanks.
>
>> > struct mempolicy_args {
>> > unsigned short mode; /* policy mode */
>> > unsigned short mode_flags; /* policy mode flags */
>> > int home_node; /* mbind: use MPOL_MF_HOME_NODE */
>> > nodemask_t *policy_nodes; /* get/set/mbind */
>> > unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
>> > int policy_node; /* get: policy node information */
>> > };
>>
>> Because we use more and more parameters to describe the mempolicy, I
>> think it's a good idea to replace some parameters with struct. But I
>> don't think it's a good idea to put unrelated stuff into the struct.
>> For example,
>>
>> struct mempolicy_param {
>> unsigned short mode; /* policy mode */
>> unsigned short mode_flags; /* policy mode flags */
>> int home_node; /* mbind: use MPOL_MF_HOME_NODE */
>> nodemask_t *policy_nodes;
>> unsigned char *il_weights; /* for mode MPOL_WEIGHTED_INTERLEAVE */
>> };
>>
>> describe the parameters to create the mempolicy. It can be used by
>> set/get_mempolicy() and mbind(). So, I think that it's a good
>> abstraction. But "policy_node" has nothing to do with set_mempolicy()
>> and mbind(). So I think that we shouldn't add it into the struct. It's
>> totally OK to use different parameters for different functions. For
>> example,
>>
>> long do_set_mempolicy(struct mempolicy_param *mparam);
>> long do_mbind(unsigned long start, unsigned long len,
>> struct mempolicy_param *mparam, unsigned long flags);
>> long do_get_task_mempolicy(struct mempolicy_param *mparam, int
>> *policy_node);
>>
>> This isn't the full list. My point is to use separate parameter for
>> something specific for some function.
>>
>
> this is the internal structure, but i get the point, we can drop it from
> the structure and extend the arg list internally.
>
> I'd originally thought to just remove the policy_node stuff all
> together from get_mempolicy2(). Do you prefer to have a separate struct
> for set/get interfaces so that the get interface struct can be extended?
>
> All the MPOL_F_NODE "alternate data fetch" mechanisms from
> get_mempolicy() feel like more of a wart than a feature. And presently
> the only data returned in policy_node is the next allocation node for
> interleave. That's not even particularly useful, so I'm of a mind to
> remove it.
>
> Assuming we remove policy_node altogether... do we still break up the
> set/get interface into separate structures to avoid this in the future?
I have no much experience at ABI definition. So, I want to get guidance
from more experienced people on this.
Is it good to implement all functionality of get_mempolicy() with
get_mempolicy2(), so we can deprecate get_mempolicy() and remove it
finally? So, users don't need to use 2 similar syscalls?
And, IIUC, we will not get policy_node, addr_node, and policy config at
the same time, is it better to use a union instead of struct in
get_mempolicy2()?
>> > struct mpol_args {
>> > /* Basic mempolicy settings */
>> > __u16 mode;
>> > __u16 mode_flags;
>> > __s32 home_node;
>> > __aligned_u64 pol_nodes;
>> > __aligned_u64 *il_weights; /* of size pol_maxnodes */
>> > __u64 pol_maxnodes;
>> > __s32 policy_node;
>> > };
>>
>> Same as my idea above. I think we shouldn't add policy_node for
>> set_mempolicy2()/mbind2(). That will make users confusing. We can use
>> a different struct for get_mempolicy2().
>>
>
> See above.
--
Best Regards,
Huang, Ying
On Wed, Dec 20, 2023 at 10:27:06AM +0800, Huang, Ying wrote:
> Gregory Price <[email protected]> writes:
>
> > Assuming we remove policy_node altogether... do we still break up the
> > set/get interface into separate structures to avoid this in the future?
>
> I have no much experience at ABI definition. So, I want to get guidance
> from more experienced people on this.
>
> Is it good to implement all functionality of get_mempolicy() with
> get_mempolicy2(), so we can deprecate get_mempolicy() and remove it
> finally? So, users don't need to use 2 similar syscalls?
>
> And, IIUC, we will not get policy_node, addr_node, and policy config at
> the same time, is it better to use a union instead of struct in
> get_mempolicy2()?
>
We discussed using flags to change the operation of mempolicy earlier
and it was expressed that multiplexing syscalls via flags is no longer
a preferred design because it increases complexity in the long term.
The mems_allowed extension to get_mempolicy() is basically this kind of
multiplexing. So ultimately I think it better to simply remove that
functionality from get_mempolicy2().
Further: it's not even technically *part* of mempolicy, it's part of
cpusets, and is accessible via sysfs through some combination of
cpuset.mems and cpuset.mems.effective.
So the mems_allowed part of get_mempolicy() has already been deprecated
in that way. Doesn't seem worth it to add it to mempolicy2.
The `policy_node` is more of a question as to whether it's even useful.
Right now it only applies to interleave policies... but it's also
insanely racey. The moment you pluck the next interleave target, it's
liable to change. I don't know how anyone would even use this.
If we drop it, we can alway add it back in with an extension if someone
actually has a use-case for it and we decide to fully deprecate
get_mempolicy() (which seems unlikely, btw).
In either case, the extension I made allows get_mempolicy() to be used
to fetch policy_node via the original method, for new policies, so that
would cover it if anyone is actually using it.
~Gregory
Gregory Price <[email protected]> writes:
> On Wed, Dec 20, 2023 at 10:27:06AM +0800, Huang, Ying wrote:
>> Gregory Price <[email protected]> writes:
>>
>> > Assuming we remove policy_node altogether... do we still break up the
>> > set/get interface into separate structures to avoid this in the future?
>>
>> I have no much experience at ABI definition. So, I want to get guidance
>> from more experienced people on this.
>>
>> Is it good to implement all functionality of get_mempolicy() with
>> get_mempolicy2(), so we can deprecate get_mempolicy() and remove it
>> finally? So, users don't need to use 2 similar syscalls?
>>
>> And, IIUC, we will not get policy_node, addr_node, and policy config at
>> the same time, is it better to use a union instead of struct in
>> get_mempolicy2()?
>>
>
> We discussed using flags to change the operation of mempolicy earlier
> and it was expressed that multiplexing syscalls via flags is no longer
> a preferred design because it increases complexity in the long term.
In general, I agree with that. "ioctl" isn't the best pattern to define
syscall.
> The mems_allowed extension to get_mempolicy() is basically this kind of
> multiplexing. So ultimately I think it better to simply remove that
> functionality from get_mempolicy2().
>
> Further: it's not even technically *part* of mempolicy, it's part of
> cpusets, and is accessible via sysfs through some combination of
> cpuset.mems and cpuset.mems.effective.
>
> So the mems_allowed part of get_mempolicy() has already been deprecated
> in that way. Doesn't seem worth it to add it to mempolicy2.
>
>
> The `policy_node` is more of a question as to whether it's even useful.
> Right now it only applies to interleave policies... but it's also
> insanely racey. The moment you pluck the next interleave target, it's
> liable to change. I don't know how anyone would even use this.
Both sounds reasonable for me. How about add this into the patch
description? This will help anyone who want to know why the syscall is
defined this way.
> If we drop it, we can alway add it back in with an extension if someone
> actually has a use-case for it and we decide to fully deprecate
> get_mempolicy() (which seems unlikely, btw).
I still think it's possible, after decades.
> In either case, the extension I made allows get_mempolicy() to be used
> to fetch policy_node via the original method, for new policies, so that
> would cover it if anyone is actually using it.
--
Best Regards,
Huang, Ying
Hi Gregory,
kernel test robot noticed the following build warnings:
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Gregory-Price/mm-mempolicy-implement-the-sysfs-based-weighted_interleave-interface/20231219-074837
base: https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools.git perf-tools
patch link: https://lore.kernel.org/r/20231218194631.21667-12-gregory.price%40memverge.com
patch subject: [PATCH v4 11/11] mm/mempolicy: extend set_mempolicy2 and mbind2 to support weighted interleave
config: x86_64-randconfig-161-20231219 (https://download.01.org/0day-ci/archive/20231220/[email protected]/config)
compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Reported-by: Dan Carpenter <[email protected]>
| Closes: https://lore.kernel.org/r/[email protected]/
smatch warnings:
mm/mempolicy.c:2044 __do_sys_get_mempolicy2() warn: maybe return -EFAULT instead of the bytes remaining?
mm/mempolicy.c:2044 __do_sys_get_mempolicy2() warn: maybe return -EFAULT instead of the bytes remaining?
vim +2044 mm/mempolicy.c
a2af87404eb73e Gregory Price 2023-12-18 1992 SYSCALL_DEFINE4(get_mempolicy2, struct mpol_args __user *, uargs, size_t, usize,
a2af87404eb73e Gregory Price 2023-12-18 1993 unsigned long, addr, unsigned long, flags)
a2af87404eb73e Gregory Price 2023-12-18 1994 {
a2af87404eb73e Gregory Price 2023-12-18 1995 struct mpol_args kargs;
a2af87404eb73e Gregory Price 2023-12-18 1996 struct mempolicy_args margs;
a2af87404eb73e Gregory Price 2023-12-18 1997 int err;
a2af87404eb73e Gregory Price 2023-12-18 1998 nodemask_t policy_nodemask;
a2af87404eb73e Gregory Price 2023-12-18 1999 unsigned long __user *nodes_ptr;
8bfd7ddc0dd439 Gregory Price 2023-12-18 2000 unsigned char __user *weights_ptr;
8bfd7ddc0dd439 Gregory Price 2023-12-18 2001 unsigned char weights[MAX_NUMNODES];
a2af87404eb73e Gregory Price 2023-12-18 2002
a2af87404eb73e Gregory Price 2023-12-18 2003 if (flags & ~(MPOL_F_ADDR))
a2af87404eb73e Gregory Price 2023-12-18 2004 return -EINVAL;
a2af87404eb73e Gregory Price 2023-12-18 2005
a2af87404eb73e Gregory Price 2023-12-18 2006 /* initialize any memory liable to be copied to userland */
a2af87404eb73e Gregory Price 2023-12-18 2007 memset(&margs, 0, sizeof(margs));
8bfd7ddc0dd439 Gregory Price 2023-12-18 2008 memset(weights, 0, sizeof(weights));
a2af87404eb73e Gregory Price 2023-12-18 2009
a2af87404eb73e Gregory Price 2023-12-18 2010 err = copy_struct_from_user(&kargs, sizeof(kargs), uargs, usize);
a2af87404eb73e Gregory Price 2023-12-18 2011 if (err)
a2af87404eb73e Gregory Price 2023-12-18 2012 return -EINVAL;
a2af87404eb73e Gregory Price 2023-12-18 2013
8bfd7ddc0dd439 Gregory Price 2023-12-18 2014 if (kargs.il_weights)
8bfd7ddc0dd439 Gregory Price 2023-12-18 2015 margs.il_weights = weights;
8bfd7ddc0dd439 Gregory Price 2023-12-18 2016 else
8bfd7ddc0dd439 Gregory Price 2023-12-18 2017 margs.il_weights = NULL;
8bfd7ddc0dd439 Gregory Price 2023-12-18 2018
a2af87404eb73e Gregory Price 2023-12-18 2019 margs.policy_nodes = kargs.pol_nodes ? &policy_nodemask : NULL;
a2af87404eb73e Gregory Price 2023-12-18 2020 if (flags & MPOL_F_ADDR)
a2af87404eb73e Gregory Price 2023-12-18 2021 err = do_get_vma_mempolicy(untagged_addr(addr), NULL, &margs);
a2af87404eb73e Gregory Price 2023-12-18 2022 else
a2af87404eb73e Gregory Price 2023-12-18 2023 err = do_get_task_mempolicy(&margs);
a2af87404eb73e Gregory Price 2023-12-18 2024
a2af87404eb73e Gregory Price 2023-12-18 2025 if (err)
a2af87404eb73e Gregory Price 2023-12-18 2026 return err;
a2af87404eb73e Gregory Price 2023-12-18 2027
a2af87404eb73e Gregory Price 2023-12-18 2028 kargs.mode = margs.mode;
a2af87404eb73e Gregory Price 2023-12-18 2029 kargs.mode_flags = margs.mode_flags;
a2af87404eb73e Gregory Price 2023-12-18 2030 kargs.policy_node = margs.policy_node;
a2af87404eb73e Gregory Price 2023-12-18 2031 kargs.home_node = margs.home_node;
a2af87404eb73e Gregory Price 2023-12-18 2032 if (kargs.pol_nodes) {
a2af87404eb73e Gregory Price 2023-12-18 2033 nodes_ptr = u64_to_user_ptr(kargs.pol_nodes);
a2af87404eb73e Gregory Price 2023-12-18 2034 err = copy_nodes_to_user(nodes_ptr, kargs.pol_maxnodes,
a2af87404eb73e Gregory Price 2023-12-18 2035 margs.policy_nodes);
a2af87404eb73e Gregory Price 2023-12-18 2036 if (err)
a2af87404eb73e Gregory Price 2023-12-18 2037 return err;
This looks wrong as well.
a2af87404eb73e Gregory Price 2023-12-18 2038 }
a2af87404eb73e Gregory Price 2023-12-18 2039
8bfd7ddc0dd439 Gregory Price 2023-12-18 2040 if (kargs.mode == MPOL_WEIGHTED_INTERLEAVE && kargs.il_weights) {
8bfd7ddc0dd439 Gregory Price 2023-12-18 2041 weights_ptr = u64_to_user_ptr(kargs.il_weights);
8bfd7ddc0dd439 Gregory Price 2023-12-18 2042 err = copy_to_user(weights_ptr, weights, kargs.pol_maxnodes);
8bfd7ddc0dd439 Gregory Price 2023-12-18 2043 if (err)
8bfd7ddc0dd439 Gregory Price 2023-12-18 @2044 return err;
This should return -EFAULT same as the copy_to_user() on the next line.
8bfd7ddc0dd439 Gregory Price 2023-12-18 2045 }
8bfd7ddc0dd439 Gregory Price 2023-12-18 2046
a2af87404eb73e Gregory Price 2023-12-18 2047 return copy_to_user(uargs, &kargs, usize) ? -EFAULT : 0;
a2af87404eb73e Gregory Price 2023-12-18 2048 }
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki