LinuxLists.cc - [PART3 Patch v2 00/14] introduce N

2012-11-15 08:51:34

Subject: [PART3 Patch v2 00/14] introduce N_MEMORY

This patch is part3 of the following patchset:
https://lkml.org/lkml/2012/10/29/319

Part1 is here:
https://lkml.org/lkml/2012/10/31/30

Part2 is here:
https://lkml.org/lkml/2012/10/31/73

Part4 is here:
https://lkml.org/lkml/2012/10/31/129

Part5 is here:
https://lkml.org/lkml/2012/10/31/145

Part6 is here:
https://lkml.org/lkml/2012/10/31/248

You can apply this patchset without the other parts.

Note: part1 and part2 are in mm tree now. part5 are being reimplemented(We will
post it some days later).

We need a node which only contains movable memory. This feature is very
important for node hotplug. So we will add a new nodemask
for all memory. N_MEMORY contains movable memory but N_HIGH_MEMORY
doesn't contain it.

The meaning of N_MEMORY and N_HIGH_MEMORY nodemask:
1. N_HIGH_MEMORY: the node contains the memory that kernel can use. movable
node aren't in this nodemask.
2. N_MEMORY: the node contains memory.

Why we intrdouce a new nodemask, not rename N_HIGH_MEMORY to N_MEMORY?

See the following two codes:
1.
==========================
static void *__meminit alloc_page_cgroup(size_t size, int nid)
{
gfp_t flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN;
void *addr = NULL;

addr = alloc_pages_exact_nid(nid, size, flags);
if (addr) {
kmemleak_alloc(addr, size, 1, flags);
return addr;
}

if (node_state(nid, N_HIGH_MEMORY))
addr = vzalloc_node(size, nid);
else
addr = vzalloc(size);

return addr;
}
==========================
If the node only has ZONE_MOVABLE memory, we should use vzalloc().
So we should have a mask that stores the node which has memory that
the kernel can use.

2.
==========================
static int mpol_set_nodemask(struct mempolicy *pol,
const nodemask_t *nodes, struct nodemask_scratch *nsc)
{
int ret;

/* if mode is MPOL_DEFAULT, pol is NULL. This is right. */
if (pol == NULL)
return 0;
/* Check N_HIGH_MEMORY */
nodes_and(nsc->mask1,
cpuset_current_mems_allowed, node_states[N_HIGH_MEMORY]);
...
if (pol->flags & MPOL_F_RELATIVE_NODES)
mpol_relative_nodemask(&nsc->mask2, nodes,&nsc->mask1);
else
nodes_and(nsc->mask2, *nodes, nsc->mask1);
...
}
==========================
If the user specifies 2 nodes: one has ZONE_MOVABLE memory, and the other one
doesn't. The cpuset for this task contains all nodes. nsc->mask2 should contain
these 2 nodes. So we should hava a mask that store the node which has memory,
and use this mask to calculate nsc->mask1.

The movable node will implemtent in part4. So N_MEMORY is equal to N_HIGH_MEMORY
now.

Changes from v1 to v2:
1. add your Signed-off-by, because I am on the the patch delivery path. Andrew
Morton tells me this.
2. patch13: The newest kernel adds some codes which use N_HIGH_MEMORY. It shoule
be N_MEMORY now.

Lai Jiangshan (14):
node_states: introduce N_MEMORY
cpuset: use N_MEMORY instead N_HIGH_MEMORY
procfs: use N_MEMORY instead N_HIGH_MEMORY
memcontrol: use N_MEMORY instead N_HIGH_MEMORY
oom: use N_MEMORY instead N_HIGH_MEMORY
mm,migrate: use N_MEMORY instead N_HIGH_MEMORY
mempolicy: use N_MEMORY instead N_HIGH_MEMORY
hugetlb: use N_MEMORY instead N_HIGH_MEMORY
vmstat: use N_MEMORY instead N_HIGH_MEMORY
kthread: use N_MEMORY instead N_HIGH_MEMORY
init: use N_MEMORY instead N_HIGH_MEMORY
vmscan: use N_MEMORY instead N_HIGH_MEMORY
page_alloc: use N_MEMORY instead N_HIGH_MEMORY change the node_states
initialization
hotplug: update nodemasks management

Documentation/cgroups/cpusets.txt | 2 +-
Documentation/memory-hotplug.txt | 5 ++-
arch/x86/mm/init_64.c | 4 +-
drivers/base/node.c | 2 +-
fs/proc/kcore.c | 2 +-
fs/proc/task_mmu.c | 4 +-
include/linux/cpuset.h | 2 +-
include/linux/memory.h | 1 +
include/linux/nodemask.h | 1 +
init/main.c | 2 +-
kernel/cpuset.c | 32 +++++++-------
kernel/kthread.c | 2 +-
mm/hugetlb.c | 24 +++++------
mm/memcontrol.c | 18 ++++----
mm/memory_hotplug.c | 87 ++++++++++++++++++++++++++++++++-------
mm/mempolicy.c | 12 +++---
mm/migrate.c | 2 +-
mm/oom_kill.c | 2 +-
mm/page_alloc.c | 42 ++++++++++---------
mm/page_cgroup.c | 2 +-
mm/vmscan.c | 4 +-
mm/vmstat.c | 4 +-
22 files changed, 162 insertions(+), 94 deletions(-)

--
1.8.0

2012-11-15 08:51:33

Subject: [PART3 Patch v2 00/14] introduce N_MEMORY

Subject: [PART3 Patch v2 04/14] memcontrol: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 11/14] init: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 07/14] mempolicy: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 03/14] procfs: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 01/14] node_states: introduce N_MEMORY

Subject: [PART3 Patch v2 02/14] cpuset: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 14/14] hotplug: update nodemasks management

Subject: [PART3 Patch v2 12/14] vmscan: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 13/14] page_alloc: use N_MEMORY instead N_HIGH_MEMORY change the node_states initialization

Subject: [PART3 Patch v2 08/14] hugetlb: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 09/14] vmstat: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 10/14] kthread: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 05/14] oom: use N_MEMORY instead N_HIGH_MEMORY

Subject: [PART3 Patch v2 06/14] mm,migrate: use N_MEMORY instead N_HIGH_MEMORY

Subject: Re: [PART3 Patch v2 13/14] page_alloc: use N_MEMORY instead N_HIGH_MEMORY change the node_states initialization

Subject: Re: [PART3 Patch v2 13/14] page_alloc: use N_MEMORY instead N_HIGH_MEMORY change the node_states initialization