Currently bpf is using the memlock rlimit for the memory accounting.
This approach has its downsides and over time has created a significant
amount of problems:
1) The limit is per-user, but because most bpf operations are performed
as root, the limit has a little value.
2) It's hard to come up with a specific maximum value. Especially because
the counter is shared with non-bpf use cases (e.g. memlock()).
Any specific value is either too low and creates false failures
or is too high and useless.
3) Charging is not connected to the actual memory allocation. Bpf code
should manually calculate the estimated cost and charge the counter,
and then take care of uncharging, including all fail paths.
It adds to the code complexity and makes it easy to leak a charge.
4) There is no simple way of getting the current value of the counter.
We've used drgn for it, but it's far from being convenient.
5) Cryptic -EPERM is returned on exceeding the limit. Libbpf even had
a function to "explain" this case for users.
6) rlimits are generally considered as (at least partially) obsolete.
They do not provide a comprehensive system for the control of physical
resources: memory, cpu, io etc. All resource control developments
in the recent years were related to cgroups.
In order to overcome these problems let's switch to the memory cgroup-based
memory accounting of bpf objects. With the recent addition of the percpu
memory accounting, now it's possible to provide a comprehensive accounting
of the memory used by bpf programs and maps.
This approach has the following advantages:
1) The limit is per-cgroup and hierarchical. It's way more flexible and allows
a better control over memory usage by different workloads.
2) The actual memory consumption is taken into account. It happens automatically
on the allocation time if __GFP_ACCOUNT flags is passed. Uncharging is also
performed automatically on releasing the memory. So the code on the bpf side
becomes simpler and safer.
3) There is a simple way to get the current value and statistics.
Cgroup-based accounting adds new requirements:
1) The kernel config should have CONFIG_CGROUPS and CONFIG_MEMCG_KMEM enabled.
These options are usually enabled, maybe excluding tiny builds for embedded
devices.
2) The system should have a configured cgroup hierarchy, including reasonable
memory limits and/or guarantees. Modern systems usually delegate this task
to systemd or similar task managers.
Without meeting these requirements there are no limits on how much memory bpf
can use and a non-root user is able to hurt the system by allocating too much.
But because per-user rlimits do not provide a functional system to protect
and manage physical resources anyway, anyone who seriously depends on it,
should use cgroups.
In general, if a process performs a bpf operation (e.g. creates or updates
a map), it's memory cgroup is charged. However map updates performed from
an interrupt context are charged to the memory cgroup which contained
the process, which created the map.
The patchset consists of the following parts:
1) 4 mm patches are required on the mm side, otherwise vmallocs cannot be mapped
to userspace
2) memcg-based accounting for various bpf objects: progs and maps
3) removal of the rlimit-based accounting
4) removal of rlimit adjustments in userspace samples
v8:
- extended the cover letter to be more clear on new requirements, by Daniel
- an approximate value is provided by map memlock info, by Alexei
v7:
- introduced bpf_map_kmalloc_node() and bpf_map_alloc_percpu(), by Alexei
- switched allocations made from an interrupt context to new helpers,
by Daniel
- rebase and minor fixes
v6:
- rebased to the latest version of the remote charging API
- fixed signatures, added acks
v5:
- rebased to the latest version of the remote charging API
- implemented kmem accounting from an interrupt context, by Shakeel
- rebased to latest changes in mm allowed to map vmallocs to userspace
- fixed a build issue in kselftests, by Alexei
- fixed a use-after-free bug in bpf_map_free_deferred()
- added bpf line info coverage, by Shakeel
- split bpf map charging preparations into a separate patch
v4:
- covered allocations made from an interrupt context, by Daniel
- added some clarifications to the cover letter
v3:
- droped the userspace part for further discussions/refinements,
by Andrii and Song
v2:
- fixed build issue, caused by the remaining rlimit-based accounting
for sockhash maps
Roman Gushchin (34):
mm: memcontrol: use helpers to read page's memcg data
mm: memcontrol/slab: use helpers to access slab page's memcg_data
mm: introduce page memcg flags
mm: convert page kmemcg type to a page memcg flag
bpf: memcg-based memory accounting for bpf progs
bpf: prepare for memcg-based memory accounting for bpf maps
bpf: memcg-based memory accounting for bpf maps
bpf: refine memcg-based memory accounting for arraymap maps
bpf: refine memcg-based memory accounting for cpumap maps
bpf: memcg-based memory accounting for cgroup storage maps
bpf: refine memcg-based memory accounting for devmap maps
bpf: refine memcg-based memory accounting for hashtab maps
bpf: memcg-based memory accounting for lpm_trie maps
bpf: memcg-based memory accounting for bpf ringbuffer
bpf: memcg-based memory accounting for bpf local storage maps
bpf: refine memcg-based memory accounting for sockmap and sockhash
maps
bpf: refine memcg-based memory accounting for xskmap maps
bpf: eliminate rlimit-based memory accounting for arraymap maps
bpf: eliminate rlimit-based memory accounting for bpf_struct_ops maps
bpf: eliminate rlimit-based memory accounting for cpumap maps
bpf: eliminate rlimit-based memory accounting for cgroup storage maps
bpf: eliminate rlimit-based memory accounting for devmap maps
bpf: eliminate rlimit-based memory accounting for hashtab maps
bpf: eliminate rlimit-based memory accounting for lpm_trie maps
bpf: eliminate rlimit-based memory accounting for queue_stack_maps
maps
bpf: eliminate rlimit-based memory accounting for reuseport_array maps
bpf: eliminate rlimit-based memory accounting for bpf ringbuffer
bpf: eliminate rlimit-based memory accounting for sockmap and sockhash
maps
bpf: eliminate rlimit-based memory accounting for stackmap maps
bpf: eliminate rlimit-based memory accounting for xskmap maps
bpf: eliminate rlimit-based memory accounting for bpf local storage
maps
bpf: eliminate rlimit-based memory accounting infra for bpf maps
bpf: eliminate rlimit-based memory accounting for bpf progs
bpf: samples: do not touch RLIMIT_MEMLOCK
fs/buffer.c | 2 +-
fs/iomap/buffered-io.c | 2 +-
include/linux/bpf.h | 49 ++--
include/linux/memcontrol.h | 215 +++++++++++++++-
include/linux/mm.h | 22 --
include/linux/mm_types.h | 5 +-
include/linux/page-flags.h | 11 +-
include/trace/events/writeback.h | 2 +-
kernel/bpf/arraymap.c | 30 +--
kernel/bpf/bpf_local_storage.c | 23 +-
kernel/bpf/bpf_struct_ops.c | 19 +-
kernel/bpf/core.c | 22 +-
kernel/bpf/cpumap.c | 39 +--
kernel/bpf/devmap.c | 25 +-
kernel/bpf/hashtab.c | 34 +--
kernel/bpf/local_storage.c | 43 +---
kernel/bpf/lpm_trie.c | 20 +-
kernel/bpf/queue_stack_maps.c | 16 +-
kernel/bpf/reuseport_array.c | 12 +-
kernel/bpf/ringbuf.c | 33 +--
kernel/bpf/stackmap.c | 16 +-
kernel/bpf/syscall.c | 241 ++++++++----------
kernel/fork.c | 7 +-
mm/debug.c | 4 +-
mm/huge_memory.c | 4 +-
mm/memcontrol.c | 139 +++++-----
mm/page_alloc.c | 8 +-
mm/page_io.c | 6 +-
mm/slab.h | 38 +--
mm/workingset.c | 2 +-
net/core/sock_map.c | 42 +--
net/xdp/xskmap.c | 16 +-
samples/bpf/map_perf_test_user.c | 6 -
samples/bpf/offwaketime_user.c | 6 -
samples/bpf/sockex2_user.c | 2 -
samples/bpf/sockex3_user.c | 2 -
samples/bpf/spintest_user.c | 6 -
samples/bpf/syscall_tp_user.c | 2 -
samples/bpf/task_fd_query_user.c | 5 -
samples/bpf/test_lru_dist.c | 3 -
samples/bpf/test_map_in_map_user.c | 6 -
samples/bpf/test_overhead_user.c | 2 -
samples/bpf/trace_event_user.c | 2 -
samples/bpf/tracex2_user.c | 6 -
samples/bpf/tracex3_user.c | 6 -
samples/bpf/tracex4_user.c | 6 -
samples/bpf/tracex5_user.c | 3 -
samples/bpf/tracex6_user.c | 3 -
samples/bpf/xdp1_user.c | 6 -
samples/bpf/xdp_adjust_tail_user.c | 6 -
samples/bpf/xdp_monitor_user.c | 5 -
samples/bpf/xdp_redirect_cpu_user.c | 6 -
samples/bpf/xdp_redirect_map_user.c | 6 -
samples/bpf/xdp_redirect_user.c | 6 -
samples/bpf/xdp_router_ipv4_user.c | 6 -
samples/bpf/xdp_rxq_info_user.c | 6 -
samples/bpf/xdp_sample_pkts_user.c | 6 -
samples/bpf/xdp_tx_iptunnel_user.c | 6 -
samples/bpf/xdpsock_user.c | 7 -
.../selftests/bpf/progs/bpf_iter_bpf_map.c | 2 +-
.../selftests/bpf/progs/map_ptr_kern.c | 7 -
61 files changed, 532 insertions(+), 756 deletions(-)
--
2.26.2
Include internal metadata into the memcg-based memory accounting.
Also include the memory allocated on updating an element.
Signed-off-by: Roman Gushchin <[email protected]>
---
net/core/sock_map.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index ddc899e83313..3ff635af737a 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -39,7 +39,7 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
attr->map_flags & ~SOCK_CREATE_FLAG_MASK)
return ERR_PTR(-EINVAL);
- stab = kzalloc(sizeof(*stab), GFP_USER);
+ stab = kzalloc(sizeof(*stab), GFP_USER | __GFP_ACCOUNT);
if (!stab)
return ERR_PTR(-ENOMEM);
@@ -975,8 +975,9 @@ static struct bpf_shtab_elem *sock_hash_alloc_elem(struct bpf_shtab *htab,
}
}
- new = kmalloc_node(htab->elem_size, GFP_ATOMIC | __GFP_NOWARN,
- htab->map.numa_node);
+ new = bpf_map_kmalloc_node(&htab->map, htab->elem_size,
+ GFP_ATOMIC | __GFP_NOWARN | __GFP_ACCOUNT,
+ htab->map.numa_node);
if (!new) {
atomic_dec(&htab->count);
return ERR_PTR(-ENOMEM);
@@ -1116,7 +1117,7 @@ static struct bpf_map *sock_hash_alloc(union bpf_attr *attr)
if (attr->key_size > MAX_BPF_STACK)
return ERR_PTR(-E2BIG);
- htab = kzalloc(sizeof(*htab), GFP_USER);
+ htab = kzalloc(sizeof(*htab), GFP_USER | __GFP_ACCOUNT);
if (!htab)
return ERR_PTR(-ENOMEM);
--
2.26.2
Do not use rlimit-based memory accounting for queue_stack maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/queue_stack_maps.c | 16 ++++------------
1 file changed, 4 insertions(+), 12 deletions(-)
diff --git a/kernel/bpf/queue_stack_maps.c b/kernel/bpf/queue_stack_maps.c
index 0ee2347ba510..f9c734aaa990 100644
--- a/kernel/bpf/queue_stack_maps.c
+++ b/kernel/bpf/queue_stack_maps.c
@@ -66,29 +66,21 @@ static int queue_stack_map_alloc_check(union bpf_attr *attr)
static struct bpf_map *queue_stack_map_alloc(union bpf_attr *attr)
{
- int ret, numa_node = bpf_map_attr_numa_node(attr);
- struct bpf_map_memory mem = {0};
+ int numa_node = bpf_map_attr_numa_node(attr);
struct bpf_queue_stack *qs;
- u64 size, queue_size, cost;
+ u64 size, queue_size;
size = (u64) attr->max_entries + 1;
- cost = queue_size = sizeof(*qs) + size * attr->value_size;
-
- ret = bpf_map_charge_init(&mem, cost);
- if (ret < 0)
- return ERR_PTR(ret);
+ queue_size = sizeof(*qs) + size * attr->value_size;
qs = bpf_map_area_alloc(queue_size, numa_node);
- if (!qs) {
- bpf_map_charge_finish(&mem);
+ if (!qs)
return ERR_PTR(-ENOMEM);
- }
memset(qs, 0, sizeof(*qs));
bpf_map_init_from_attr(&qs->map, attr);
- bpf_map_charge_move(&qs->map.memory, &mem);
qs->size = size;
raw_spin_lock_init(&qs->lock);
--
2.26.2
Since bpf is not using rlimit memlock for the memory accounting
and control, do not change the limit in sample applications.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
samples/bpf/map_perf_test_user.c | 6 ------
samples/bpf/offwaketime_user.c | 6 ------
samples/bpf/sockex2_user.c | 2 --
samples/bpf/sockex3_user.c | 2 --
samples/bpf/spintest_user.c | 6 ------
samples/bpf/syscall_tp_user.c | 2 --
samples/bpf/task_fd_query_user.c | 5 -----
samples/bpf/test_lru_dist.c | 3 ---
samples/bpf/test_map_in_map_user.c | 6 ------
samples/bpf/test_overhead_user.c | 2 --
samples/bpf/trace_event_user.c | 2 --
samples/bpf/tracex2_user.c | 6 ------
samples/bpf/tracex3_user.c | 6 ------
samples/bpf/tracex4_user.c | 6 ------
samples/bpf/tracex5_user.c | 3 ---
samples/bpf/tracex6_user.c | 3 ---
samples/bpf/xdp1_user.c | 6 ------
samples/bpf/xdp_adjust_tail_user.c | 6 ------
samples/bpf/xdp_monitor_user.c | 5 -----
samples/bpf/xdp_redirect_cpu_user.c | 6 ------
samples/bpf/xdp_redirect_map_user.c | 6 ------
samples/bpf/xdp_redirect_user.c | 6 ------
samples/bpf/xdp_router_ipv4_user.c | 6 ------
samples/bpf/xdp_rxq_info_user.c | 6 ------
samples/bpf/xdp_sample_pkts_user.c | 6 ------
samples/bpf/xdp_tx_iptunnel_user.c | 6 ------
samples/bpf/xdpsock_user.c | 7 -------
27 files changed, 132 deletions(-)
diff --git a/samples/bpf/map_perf_test_user.c b/samples/bpf/map_perf_test_user.c
index 8b13230b4c46..9db949290a78 100644
--- a/samples/bpf/map_perf_test_user.c
+++ b/samples/bpf/map_perf_test_user.c
@@ -421,7 +421,6 @@ static void fixup_map(struct bpf_object *obj)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
int nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
struct bpf_link *links[8];
struct bpf_program *prog;
@@ -430,11 +429,6 @@ int main(int argc, char **argv)
char filename[256];
int i = 0;
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
if (argc > 1)
test_flags = atoi(argv[1]) ? : test_flags;
diff --git a/samples/bpf/offwaketime_user.c b/samples/bpf/offwaketime_user.c
index 5734cfdaaacb..73a986876c1a 100644
--- a/samples/bpf/offwaketime_user.c
+++ b/samples/bpf/offwaketime_user.c
@@ -95,18 +95,12 @@ static void int_exit(int sig)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_object *obj = NULL;
struct bpf_link *links[2];
struct bpf_program *prog;
int delay = 1, i = 0;
char filename[256];
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
if (load_kallsyms()) {
printf("failed to process /proc/kallsyms\n");
return 2;
diff --git a/samples/bpf/sockex2_user.c b/samples/bpf/sockex2_user.c
index af925a5afd1d..bafa567b840c 100644
--- a/samples/bpf/sockex2_user.c
+++ b/samples/bpf/sockex2_user.c
@@ -16,7 +16,6 @@ struct pair {
int main(int ac, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_object *obj;
int map_fd, prog_fd;
char filename[256];
@@ -24,7 +23,6 @@ int main(int ac, char **argv)
FILE *f;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
- setrlimit(RLIMIT_MEMLOCK, &r);
if (bpf_prog_load(filename, BPF_PROG_TYPE_SOCKET_FILTER,
&obj, &prog_fd))
diff --git a/samples/bpf/sockex3_user.c b/samples/bpf/sockex3_user.c
index 7793f6a6ae7e..6ae99ecc766c 100644
--- a/samples/bpf/sockex3_user.c
+++ b/samples/bpf/sockex3_user.c
@@ -26,7 +26,6 @@ struct pair {
int main(int argc, char **argv)
{
int i, sock, key, fd, main_prog_fd, jmp_table_fd, hash_map_fd;
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_program *prog;
struct bpf_object *obj;
const char *section;
@@ -34,7 +33,6 @@ int main(int argc, char **argv)
FILE *f;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
- setrlimit(RLIMIT_MEMLOCK, &r);
obj = bpf_object__open_file(filename, NULL);
if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/spintest_user.c b/samples/bpf/spintest_user.c
index f090d0dc60d6..0d7e1e5a8658 100644
--- a/samples/bpf/spintest_user.c
+++ b/samples/bpf/spintest_user.c
@@ -10,7 +10,6 @@
int main(int ac, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
char filename[256], symbol[256];
struct bpf_object *obj = NULL;
struct bpf_link *links[20];
@@ -20,11 +19,6 @@ int main(int ac, char **argv)
const char *section;
struct ksym *sym;
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
if (load_kallsyms()) {
printf("failed to process /proc/kallsyms\n");
return 2;
diff --git a/samples/bpf/syscall_tp_user.c b/samples/bpf/syscall_tp_user.c
index 76a1d00128fb..a0ebf1833ed3 100644
--- a/samples/bpf/syscall_tp_user.c
+++ b/samples/bpf/syscall_tp_user.c
@@ -115,7 +115,6 @@ static int test(char *filename, int num_progs)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
int opt, num_progs = 1;
char filename[256];
@@ -131,7 +130,6 @@ int main(int argc, char **argv)
}
}
- setrlimit(RLIMIT_MEMLOCK, &r);
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
return test(filename, num_progs);
diff --git a/samples/bpf/task_fd_query_user.c b/samples/bpf/task_fd_query_user.c
index b68bd2f8fdc9..0f2050ff54f9 100644
--- a/samples/bpf/task_fd_query_user.c
+++ b/samples/bpf/task_fd_query_user.c
@@ -290,16 +290,11 @@ static int test_debug_fs_uprobe(char *binary_path, long offset, bool is_return)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
extern char __executable_start;
char filename[256], buf[256];
__u64 uprobe_file_offset;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
if (load_kallsyms()) {
printf("failed to process /proc/kallsyms\n");
diff --git a/samples/bpf/test_lru_dist.c b/samples/bpf/test_lru_dist.c
index b313dba4111b..c92c5c06b965 100644
--- a/samples/bpf/test_lru_dist.c
+++ b/samples/bpf/test_lru_dist.c
@@ -489,7 +489,6 @@ static void test_parallel_lru_loss(int map_type, int map_flags, int nr_tasks)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
int map_flags[] = {0, BPF_F_NO_COMMON_LRU};
const char *dist_file;
int nr_tasks = 1;
@@ -508,8 +507,6 @@ int main(int argc, char **argv)
setbuf(stdout, NULL);
- assert(!setrlimit(RLIMIT_MEMLOCK, &r));
-
srand(time(NULL));
nr_cpus = bpf_num_possible_cpus();
diff --git a/samples/bpf/test_map_in_map_user.c b/samples/bpf/test_map_in_map_user.c
index 98656de56b83..472d65c70354 100644
--- a/samples/bpf/test_map_in_map_user.c
+++ b/samples/bpf/test_map_in_map_user.c
@@ -114,17 +114,11 @@ static void test_map_in_map(void)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_link *link = NULL;
struct bpf_program *prog;
struct bpf_object *obj;
char filename[256];
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
obj = bpf_object__open_file(filename, NULL);
if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/test_overhead_user.c b/samples/bpf/test_overhead_user.c
index 94f74112a20e..c100fd46cd8a 100644
--- a/samples/bpf/test_overhead_user.c
+++ b/samples/bpf/test_overhead_user.c
@@ -125,12 +125,10 @@ static void unload_progs(void)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
char filename[256];
int num_cpu = 8;
int test_flags = ~0;
- setrlimit(RLIMIT_MEMLOCK, &r);
if (argc > 1)
test_flags = atoi(argv[1]) ? : test_flags;
diff --git a/samples/bpf/trace_event_user.c b/samples/bpf/trace_event_user.c
index ac1ba368195c..9664749bf618 100644
--- a/samples/bpf/trace_event_user.c
+++ b/samples/bpf/trace_event_user.c
@@ -294,13 +294,11 @@ static void test_bpf_perf_event(void)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_object *obj = NULL;
char filename[256];
int error = 1;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
- setrlimit(RLIMIT_MEMLOCK, &r);
signal(SIGINT, err_exit);
signal(SIGTERM, err_exit);
diff --git a/samples/bpf/tracex2_user.c b/samples/bpf/tracex2_user.c
index 3d6eab711d23..1626d51dfffd 100644
--- a/samples/bpf/tracex2_user.c
+++ b/samples/bpf/tracex2_user.c
@@ -116,7 +116,6 @@ static void int_exit(int sig)
int main(int ac, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
long key, next_key, value;
struct bpf_link *links[2];
struct bpf_program *prog;
@@ -125,11 +124,6 @@ int main(int ac, char **argv)
int i, j = 0;
FILE *f;
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
obj = bpf_object__open_file(filename, NULL);
if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/tracex3_user.c b/samples/bpf/tracex3_user.c
index 83e0fecbb01a..33e16ba39f25 100644
--- a/samples/bpf/tracex3_user.c
+++ b/samples/bpf/tracex3_user.c
@@ -107,7 +107,6 @@ static void print_hist(int fd)
int main(int ac, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_link *links[2];
struct bpf_program *prog;
struct bpf_object *obj;
@@ -127,11 +126,6 @@ int main(int ac, char **argv)
}
}
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
obj = bpf_object__open_file(filename, NULL);
if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/tracex4_user.c b/samples/bpf/tracex4_user.c
index e8faf8f184ae..cea399424bca 100644
--- a/samples/bpf/tracex4_user.c
+++ b/samples/bpf/tracex4_user.c
@@ -48,18 +48,12 @@ static void print_old_objects(int fd)
int main(int ac, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_link *links[2];
struct bpf_program *prog;
struct bpf_object *obj;
char filename[256];
int map_fd, i, j = 0;
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
- return 1;
- }
-
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
obj = bpf_object__open_file(filename, NULL);
if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/tracex5_user.c b/samples/bpf/tracex5_user.c
index c17d3fb5fd64..08dfdc77ad2a 100644
--- a/samples/bpf/tracex5_user.c
+++ b/samples/bpf/tracex5_user.c
@@ -34,7 +34,6 @@ static void install_accept_all_seccomp(void)
int main(int ac, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_link *link = NULL;
struct bpf_program *prog;
struct bpf_object *obj;
@@ -43,8 +42,6 @@ int main(int ac, char **argv)
char filename[256];
FILE *f;
- setrlimit(RLIMIT_MEMLOCK, &r);
-
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
obj = bpf_object__open_file(filename, NULL);
if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/tracex6_user.c b/samples/bpf/tracex6_user.c
index 33df9784775d..28296f40c133 100644
--- a/samples/bpf/tracex6_user.c
+++ b/samples/bpf/tracex6_user.c
@@ -175,15 +175,12 @@ static void test_bpf_perf_event(void)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_link *links[2];
struct bpf_program *prog;
struct bpf_object *obj;
char filename[256];
int i = 0;
- setrlimit(RLIMIT_MEMLOCK, &r);
-
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
obj = bpf_object__open_file(filename, NULL);
if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c
index c447ad9e3a1d..116e39f6b666 100644
--- a/samples/bpf/xdp1_user.c
+++ b/samples/bpf/xdp1_user.c
@@ -79,7 +79,6 @@ static void usage(const char *prog)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
@@ -117,11 +116,6 @@ int main(int argc, char **argv)
return 1;
}
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
ifindex = if_nametoindex(argv[optind]);
if (!ifindex) {
perror("if_nametoindex");
diff --git a/samples/bpf/xdp_adjust_tail_user.c b/samples/bpf/xdp_adjust_tail_user.c
index ba482dc3da33..a70b094c8ec5 100644
--- a/samples/bpf/xdp_adjust_tail_user.c
+++ b/samples/bpf/xdp_adjust_tail_user.c
@@ -82,7 +82,6 @@ static void usage(const char *cmd)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
@@ -143,11 +142,6 @@ int main(int argc, char **argv)
}
}
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
- return 1;
- }
-
if (!ifindex) {
fprintf(stderr, "Invalid ifname\n");
return 1;
diff --git a/samples/bpf/xdp_monitor_user.c b/samples/bpf/xdp_monitor_user.c
index 03d0a182913f..49ebc49aefc3 100644
--- a/samples/bpf/xdp_monitor_user.c
+++ b/samples/bpf/xdp_monitor_user.c
@@ -687,7 +687,6 @@ static void print_bpf_prog_info(void)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_program *prog;
int longindex = 0, opt;
int ret = EXIT_FAILURE;
@@ -719,10 +718,6 @@ int main(int argc, char **argv)
}
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return ret;
- }
/* Remove tracepoint program when program is interrupted or killed */
signal(SIGINT, int_exit);
diff --git a/samples/bpf/xdp_redirect_cpu_user.c b/samples/bpf/xdp_redirect_cpu_user.c
index f78cb18319aa..576411612523 100644
--- a/samples/bpf/xdp_redirect_cpu_user.c
+++ b/samples/bpf/xdp_redirect_cpu_user.c
@@ -765,7 +765,6 @@ static int load_cpumap_prog(char *file_name, char *prog_name,
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
char *prog_name = "xdp_cpu_map5_lb_hash_ip_pairs";
char *mprog_filename = "xdp_redirect_kern.o";
char *redir_interface = NULL, *redir_map = NULL;
@@ -804,11 +803,6 @@ int main(int argc, char **argv)
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
prog_load_attr.file = filename;
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
return err;
diff --git a/samples/bpf/xdp_redirect_map_user.c b/samples/bpf/xdp_redirect_map_user.c
index 35e16dee613e..31131b6e7782 100644
--- a/samples/bpf/xdp_redirect_map_user.c
+++ b/samples/bpf/xdp_redirect_map_user.c
@@ -96,7 +96,6 @@ static void usage(const char *prog)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
@@ -135,11 +134,6 @@ int main(int argc, char **argv)
return 1;
}
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
ifindex_in = if_nametoindex(argv[optind]);
if (!ifindex_in)
ifindex_in = strtoul(argv[optind], NULL, 0);
diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c
index 9ca2bf457cda..41d705c3a1f7 100644
--- a/samples/bpf/xdp_redirect_user.c
+++ b/samples/bpf/xdp_redirect_user.c
@@ -97,7 +97,6 @@ static void usage(const char *prog)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
@@ -136,11 +135,6 @@ int main(int argc, char **argv)
return 1;
}
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
ifindex_in = if_nametoindex(argv[optind]);
if (!ifindex_in)
ifindex_in = strtoul(argv[optind], NULL, 0);
diff --git a/samples/bpf/xdp_router_ipv4_user.c b/samples/bpf/xdp_router_ipv4_user.c
index c2da1b51ff95..b5f03cb17a3c 100644
--- a/samples/bpf/xdp_router_ipv4_user.c
+++ b/samples/bpf/xdp_router_ipv4_user.c
@@ -625,7 +625,6 @@ static void usage(const char *prog)
int main(int ac, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
@@ -670,11 +669,6 @@ int main(int ac, char **argv)
return 1;
}
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
return 1;
diff --git a/samples/bpf/xdp_rxq_info_user.c b/samples/bpf/xdp_rxq_info_user.c
index 93fa1bc54f13..74a2926eba08 100644
--- a/samples/bpf/xdp_rxq_info_user.c
+++ b/samples/bpf/xdp_rxq_info_user.c
@@ -450,7 +450,6 @@ static void stats_poll(int interval, int action, __u32 cfg_opt)
int main(int argc, char **argv)
{
__u32 cfg_options= NO_TOUCH ; /* Default: Don't touch packet memory */
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
@@ -474,11 +473,6 @@ int main(int argc, char **argv)
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
prog_load_attr.file = filename;
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
return EXIT_FAIL;
diff --git a/samples/bpf/xdp_sample_pkts_user.c b/samples/bpf/xdp_sample_pkts_user.c
index 4b2a300c750c..706475e004cb 100644
--- a/samples/bpf/xdp_sample_pkts_user.c
+++ b/samples/bpf/xdp_sample_pkts_user.c
@@ -109,7 +109,6 @@ static void usage(const char *prog)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
@@ -143,11 +142,6 @@ int main(int argc, char **argv)
return 1;
}
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK)");
- return 1;
- }
-
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
prog_load_attr.file = filename;
diff --git a/samples/bpf/xdp_tx_iptunnel_user.c b/samples/bpf/xdp_tx_iptunnel_user.c
index a419bee151a8..1d4f305d02aa 100644
--- a/samples/bpf/xdp_tx_iptunnel_user.c
+++ b/samples/bpf/xdp_tx_iptunnel_user.c
@@ -155,7 +155,6 @@ int main(int argc, char **argv)
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
int min_port = 0, max_port = 0, vip2tnl_map_fd;
const char *optstr = "i:a:p:s:d:m:T:P:FSNh";
unsigned char opt_flags[256] = {};
@@ -254,11 +253,6 @@ int main(int argc, char **argv)
}
}
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
- return 1;
- }
-
if (!ifindex) {
fprintf(stderr, "Invalid ifname\n");
return 1;
diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c
index 2567f0db5aca..f3ce4dac3a1f 100644
--- a/samples/bpf/xdpsock_user.c
+++ b/samples/bpf/xdpsock_user.c
@@ -1463,7 +1463,6 @@ static void enter_xsks_into_map(struct bpf_object *obj)
int main(int argc, char **argv)
{
- struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
bool rx = false, tx = false;
struct xsk_umem_info *umem;
struct bpf_object *obj;
@@ -1473,12 +1472,6 @@ int main(int argc, char **argv)
parse_command_line(argc, argv);
- if (setrlimit(RLIMIT_MEMLOCK, &r)) {
- fprintf(stderr, "ERROR: setrlimit(RLIMIT_MEMLOCK) \"%s\"\n",
- strerror(errno));
- exit(EXIT_FAILURE);
- }
-
if (opt_num_xsks > 1)
load_xdp_program(argv, &obj);
--
2.26.2
Do not use rlimit-based memory accounting for cgroup storage maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/local_storage.c | 21 +--------------------
1 file changed, 1 insertion(+), 20 deletions(-)
diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index aae17d29538e..d7d4587415a6 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -287,8 +287,6 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
{
int numa_node = bpf_map_attr_numa_node(attr);
struct bpf_cgroup_storage_map *map;
- struct bpf_map_memory mem;
- int ret;
if (attr->key_size != sizeof(struct bpf_cgroup_storage_key) &&
attr->key_size != sizeof(__u64))
@@ -308,18 +306,10 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
/* max_entries is not used and enforced to be 0 */
return ERR_PTR(-EINVAL);
- ret = bpf_map_charge_init(&mem, sizeof(struct bpf_cgroup_storage_map));
- if (ret < 0)
- return ERR_PTR(ret);
-
map = kmalloc_node(sizeof(struct bpf_cgroup_storage_map),
__GFP_ZERO | GFP_USER | __GFP_ACCOUNT, numa_node);
- if (!map) {
- bpf_map_charge_finish(&mem);
+ if (!map)
return ERR_PTR(-ENOMEM);
- }
-
- bpf_map_charge_move(&map->map.memory, &mem);
/* copy mandatory map attributes */
bpf_map_init_from_attr(&map->map, attr);
@@ -508,9 +498,6 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
size = bpf_cgroup_storage_calculate_size(map, &pages);
- if (bpf_map_charge_memlock(map, pages))
- return ERR_PTR(-EPERM);
-
storage = kmalloc_node(sizeof(struct bpf_cgroup_storage), gfp,
map->numa_node);
if (!storage)
@@ -532,7 +519,6 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
return storage;
enomem:
- bpf_map_uncharge_memlock(map, pages);
kfree(storage);
return ERR_PTR(-ENOMEM);
}
@@ -559,16 +545,11 @@ void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage)
{
enum bpf_cgroup_storage_type stype;
struct bpf_map *map;
- u32 pages;
if (!storage)
return;
map = &storage->map->map;
-
- bpf_cgroup_storage_calculate_size(map, &pages);
- bpf_map_uncharge_memlock(map, pages);
-
stype = cgroup_storage_type(map);
if (stype == BPF_CGROUP_STORAGE_SHARED)
call_rcu(&storage->rcu, free_shared_cgroup_storage_rcu);
--
2.26.2
Account memory used by bpf local storage maps:
per-socket, per-inode and per-task storages.
Signed-off-by: Roman Gushchin <[email protected]>
---
kernel/bpf/bpf_local_storage.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
index 5d3a7af9ba9b..abd0ea385274 100644
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -67,7 +67,9 @@ bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
if (charge_mem && mem_charge(smap, owner, smap->elem_size))
return NULL;
- selem = kzalloc(smap->elem_size, GFP_ATOMIC | __GFP_NOWARN);
+ selem = bpf_map_kmalloc_node(&smap->map, smap->elem_size,
+ GFP_ATOMIC | __GFP_NOWARN | __GFP_ZERO |
+ __GFP_ACCOUNT, NUMA_NO_NODE);
if (selem) {
if (value)
memcpy(SDATA(selem)->data, value, smap->map.value_size);
@@ -264,7 +266,9 @@ int bpf_local_storage_alloc(void *owner,
if (err)
return err;
- storage = kzalloc(sizeof(*storage), GFP_ATOMIC | __GFP_NOWARN);
+ storage = bpf_map_kmalloc_node(&smap->map, sizeof(*storage),
+ GFP_ATOMIC | __GFP_NOWARN | __GFP_ZERO |
+ __GFP_ACCOUNT, NUMA_NO_NODE);
if (!storage) {
err = -ENOMEM;
goto uncharge;
@@ -546,7 +550,7 @@ struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr)
u64 cost;
int ret;
- smap = kzalloc(sizeof(*smap), GFP_USER | __GFP_NOWARN);
+ smap = kzalloc(sizeof(*smap), GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
if (!smap)
return ERR_PTR(-ENOMEM);
bpf_map_init_from_attr(&smap->map, attr);
@@ -564,7 +568,7 @@ struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr)
}
smap->buckets = kvcalloc(sizeof(*smap->buckets), nbuckets,
- GFP_USER | __GFP_NOWARN);
+ GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
if (!smap->buckets) {
bpf_map_charge_finish(&smap->map.memory);
kfree(smap);
--
2.26.2
PageKmemcg flag is currently defined as a page type (like buddy, offline,
table and guard). Semantically it means that the page was accounted as a
kernel memory by the page allocator and has to be uncharged on the
release.
As a side effect of defining the flag as a page type, the accounted page
can't be mapped to userspace (look at page_has_type() and comments above).
In particular, this blocks the accounting of vmalloc-backed memory used
by some bpf maps, because these maps do map the memory to userspace.
One option is to fix it by complicating the access to page->mapcount,
which provides some free bits for page->page_type.
But it's way better to move this flag into page->memcg_data flags.
Indeed, the flag makes no sense without enabled memory cgroups and memory
cgroup pointer set in particular.
This commit replaces PageKmemcg() and __SetPageKmemcg() with
PageMemcgKmem() and an open-coded OR operation setting the memcg pointer
with the MEMCG_DATA_KMEM bit. __ClearPageKmemcg() can be simple deleted,
as the whole memcg_data is zeroed at once.
As a bonus, on !CONFIG_MEMCG build the PageMemcgKmem() check will be
compiled out.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
include/linux/memcontrol.h | 37 +++++++++++++++++++++++++++++++++----
include/linux/page-flags.h | 11 ++---------
mm/memcontrol.c | 16 +++++-----------
mm/page_alloc.c | 4 ++--
4 files changed, 42 insertions(+), 26 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 99a4841d658b..7c9d43476166 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -346,8 +346,10 @@ extern struct mem_cgroup *root_mem_cgroup;
enum page_memcg_data_flags {
/* page->memcg_data is a pointer to an objcgs vector */
MEMCG_DATA_OBJCGS = (1UL << 0),
+ /* page has been accounted as a non-slab kernel page */
+ MEMCG_DATA_KMEM = (1UL << 1),
/* the next bit after the last actual flag */
- __NR_MEMCG_DATA_FLAGS = (1UL << 1),
+ __NR_MEMCG_DATA_FLAGS = (1UL << 2),
};
#define MEMCG_DATA_FLAGS_MASK (__NR_MEMCG_DATA_FLAGS - 1)
@@ -369,8 +371,12 @@ enum page_memcg_data_flags {
*/
static inline struct mem_cgroup *page_memcg(struct page *page)
{
+ unsigned long memcg_data = page->memcg_data;
+
VM_BUG_ON_PAGE(PageSlab(page), page);
- return (struct mem_cgroup *)page->memcg_data;
+ VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_OBJCGS, page);
+
+ return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
}
/*
@@ -387,7 +393,8 @@ static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
VM_BUG_ON_PAGE(PageSlab(page), page);
WARN_ON_ONCE(!rcu_read_lock_held());
- return (struct mem_cgroup *)READ_ONCE(page->memcg_data);
+ return (struct mem_cgroup *)(READ_ONCE(page->memcg_data) &
+ ~MEMCG_DATA_FLAGS_MASK);
}
/*
@@ -416,7 +423,21 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
if (memcg_data & MEMCG_DATA_OBJCGS)
return NULL;
- return (struct mem_cgroup *)memcg_data;
+ return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
+}
+
+/*
+ * PageMemcgKmem - check if the page has MemcgKmem flag set
+ * @page: a pointer to the page struct
+ *
+ * Checks if the page has MemcgKmem flag set. The caller must ensure that
+ * the page has an associated memory cgroup. It's not safe to call this function
+ * against some types of pages, e.g. slab pages.
+ */
+static inline bool PageMemcgKmem(struct page *page)
+{
+ VM_BUG_ON_PAGE(page->memcg_data & MEMCG_DATA_OBJCGS, page);
+ return page->memcg_data & MEMCG_DATA_KMEM;
}
#ifdef CONFIG_MEMCG_KMEM
@@ -435,6 +456,7 @@ static inline struct obj_cgroup **page_objcgs(struct page *page)
unsigned long memcg_data = READ_ONCE(page->memcg_data);
VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), page);
+ VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, page);
return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
}
@@ -454,6 +476,8 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page)
if (!memcg_data || !(memcg_data & MEMCG_DATA_OBJCGS))
return NULL;
+ VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, page);
+
return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
}
@@ -1109,6 +1133,11 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
return NULL;
}
+static inline bool PageMemcgKmem(struct page *page)
+{
+ return false;
+}
+
static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
{
return true;
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 4f6ba9379112..fc0e1bd48e73 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -715,9 +715,8 @@ PAGEFLAG_FALSE(DoubleMap)
#define PAGE_MAPCOUNT_RESERVE -128
#define PG_buddy 0x00000080
#define PG_offline 0x00000100
-#define PG_kmemcg 0x00000200
-#define PG_table 0x00000400
-#define PG_guard 0x00000800
+#define PG_table 0x00000200
+#define PG_guard 0x00000400
#define PageType(page, flag) \
((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE)
@@ -768,12 +767,6 @@ PAGE_TYPE_OPS(Buddy, buddy)
*/
PAGE_TYPE_OPS(Offline, offline)
-/*
- * If kmemcg is enabled, the buddy allocator will set PageKmemcg() on
- * pages allocated with __GFP_ACCOUNT. It gets cleared on page free.
- */
-PAGE_TYPE_OPS(Kmemcg, kmemcg)
-
/*
* Marks pages in use as page tables.
*/
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 0054b4846770..e0366e306221 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3090,8 +3090,8 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
if (memcg && !mem_cgroup_is_root(memcg)) {
ret = __memcg_kmem_charge(memcg, gfp, 1 << order);
if (!ret) {
- page->memcg_data = (unsigned long)memcg;
- __SetPageKmemcg(page);
+ page->memcg_data = (unsigned long)memcg |
+ MEMCG_DATA_KMEM;
return 0;
}
css_put(&memcg->css);
@@ -3116,10 +3116,6 @@ void __memcg_kmem_uncharge_page(struct page *page, int order)
__memcg_kmem_uncharge(memcg, nr_pages);
page->memcg_data = 0;
css_put(&memcg->css);
-
- /* slab pages do not have PageKmemcg flag set */
- if (PageKmemcg(page))
- __ClearPageKmemcg(page);
}
static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
@@ -6877,12 +6873,10 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
nr_pages = compound_nr(page);
ug->nr_pages += nr_pages;
- if (!PageKmemcg(page)) {
- ug->pgpgout++;
- } else {
+ if (PageMemcgKmem(page))
ug->nr_kmem += nr_pages;
- __ClearPageKmemcg(page);
- }
+ else
+ ug->pgpgout++;
ug->dummy_page = page;
page->memcg_data = 0;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 271133b8243b..3c53018c9c61 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1214,7 +1214,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
* Do not let hwpoison pages hit pcplists/buddy
* Untie memcg state and reset page's owner
*/
- if (memcg_kmem_enabled() && PageKmemcg(page))
+ if (memcg_kmem_enabled() && PageMemcgKmem(page))
__memcg_kmem_uncharge_page(page, order);
reset_page_owner(page, order);
return false;
@@ -1244,7 +1244,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
}
if (PageMappingFlags(page))
page->mapping = NULL;
- if (memcg_kmem_enabled() && PageKmemcg(page))
+ if (memcg_kmem_enabled() && PageMemcgKmem(page))
__memcg_kmem_uncharge_page(page, order);
if (check_free)
bad += check_free_page(page);
--
2.26.2
Extend xskmap memory accounting to include the memory taken by
the xsk_map_node structure.
Signed-off-by: Roman Gushchin <[email protected]>
---
net/xdp/xskmap.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c
index 49da2b8ace8b..eceea51182d9 100644
--- a/net/xdp/xskmap.c
+++ b/net/xdp/xskmap.c
@@ -28,7 +28,9 @@ static struct xsk_map_node *xsk_map_node_alloc(struct xsk_map *map,
struct xsk_map_node *node;
int err;
- node = kzalloc(sizeof(*node), GFP_ATOMIC | __GFP_NOWARN);
+ node = bpf_map_kmalloc_node(&map->map, sizeof(*node),
+ GFP_ATOMIC | __GFP_NOWARN | __GFP_ZERO |
+ __GFP_ACCOUNT, NUMA_NO_NODE);
if (!node)
return ERR_PTR(-ENOMEM);
--
2.26.2
Do not use rlimit-based memory accounting for bpf ringbuffer.
It has been replaced with the memcg-based memory accounting.
bpf_ringbuf_alloc() can't return anything except ERR_PTR(-ENOMEM)
and a valid pointer, so to simplify the code make it return NULL
in the first case. This allows to drop a couple of lines in
ringbuf_map_alloc() and also makes it look similar to other memory
allocating function like kmalloc().
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
Acked-by: Andrii Nakryiko <[email protected]>
---
kernel/bpf/ringbuf.c | 24 ++++--------------------
1 file changed, 4 insertions(+), 20 deletions(-)
diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c
index ee5f55d9276e..c8892b58501e 100644
--- a/kernel/bpf/ringbuf.c
+++ b/kernel/bpf/ringbuf.c
@@ -48,7 +48,6 @@ struct bpf_ringbuf {
struct bpf_ringbuf_map {
struct bpf_map map;
- struct bpf_map_memory memory;
struct bpf_ringbuf *rb;
};
@@ -135,7 +134,7 @@ static struct bpf_ringbuf *bpf_ringbuf_alloc(size_t data_sz, int numa_node)
rb = bpf_ringbuf_area_alloc(data_sz, numa_node);
if (!rb)
- return ERR_PTR(-ENOMEM);
+ return NULL;
spin_lock_init(&rb->spinlock);
init_waitqueue_head(&rb->waitq);
@@ -151,8 +150,6 @@ static struct bpf_ringbuf *bpf_ringbuf_alloc(size_t data_sz, int numa_node)
static struct bpf_map *ringbuf_map_alloc(union bpf_attr *attr)
{
struct bpf_ringbuf_map *rb_map;
- u64 cost;
- int err;
if (attr->map_flags & ~RINGBUF_CREATE_FLAG_MASK)
return ERR_PTR(-EINVAL);
@@ -174,26 +171,13 @@ static struct bpf_map *ringbuf_map_alloc(union bpf_attr *attr)
bpf_map_init_from_attr(&rb_map->map, attr);
- cost = sizeof(struct bpf_ringbuf_map) +
- sizeof(struct bpf_ringbuf) +
- attr->max_entries;
- err = bpf_map_charge_init(&rb_map->map.memory, cost);
- if (err)
- goto err_free_map;
-
rb_map->rb = bpf_ringbuf_alloc(attr->max_entries, rb_map->map.numa_node);
- if (IS_ERR(rb_map->rb)) {
- err = PTR_ERR(rb_map->rb);
- goto err_uncharge;
+ if (!rb_map->rb) {
+ kfree(rb_map);
+ return ERR_PTR(-ENOMEM);
}
return &rb_map->map;
-
-err_uncharge:
- bpf_map_charge_finish(&rb_map->map.memory);
-err_free_map:
- kfree(rb_map);
- return ERR_PTR(err);
}
static void bpf_ringbuf_free(struct bpf_ringbuf *rb)
--
2.26.2
To gather all direct accesses to struct page's memcg_data field in one
place, let's introduce 3 new helpers to use in the slab accounting code:
struct obj_cgroup **page_objcgs(struct page *page);
struct obj_cgroup **page_objcgs_check(struct page *page);
bool set_page_objcgs(struct page *page, struct obj_cgroup **objcgs);
They are similar to the corresponding API for generic pages, except that
the setter can return false, indicating that the value has been already
set from a different thread.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Cc: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
include/linux/memcontrol.h | 64 ++++++++++++++++++++++++++++++++++++++
mm/memcontrol.c | 6 ++--
mm/slab.h | 35 +++++----------------
3 files changed, 75 insertions(+), 30 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index f95c1433461c..c7ac0a5b8989 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -416,6 +416,70 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
return (struct mem_cgroup *)memcg_data;
}
+#ifdef CONFIG_MEMCG_KMEM
+/*
+ * page_objcgs - get the object cgroups vector associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the object cgroups vector associated with the page,
+ * or NULL. This function assumes that the page is known to have an
+ * associated object cgroups vector. It's not safe to call this function
+ * against pages, which might have an associated memory cgroup: e.g.
+ * kernel stack pages.
+ */
+static inline struct obj_cgroup **page_objcgs(struct page *page)
+{
+ return (struct obj_cgroup **)(READ_ONCE(page->memcg_data) & ~0x1UL);
+}
+
+/*
+ * page_objcgs_check - get the object cgroups vector associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the object cgroups vector associated with the page,
+ * or NULL. This function is safe to use if the page can be directly associated
+ * with a memory cgroup.
+ */
+static inline struct obj_cgroup **page_objcgs_check(struct page *page)
+{
+ unsigned long memcg_data = READ_ONCE(page->memcg_data);
+
+ if (memcg_data && (memcg_data & 0x1UL))
+ return (struct obj_cgroup **)(memcg_data & ~0x1UL);
+
+ return NULL;
+}
+
+/*
+ * set_page_objcgs - associate a page with a object cgroups vector
+ * @page: a pointer to the page struct
+ * @objcgs: a pointer to the object cgroups vector
+ *
+ * Atomically associates a page with a vector of object cgroups.
+ */
+static inline bool set_page_objcgs(struct page *page,
+ struct obj_cgroup **objcgs)
+{
+ return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs | 0x1UL);
+}
+#else
+static inline struct obj_cgroup **page_objcgs(struct page *page)
+{
+ return NULL;
+}
+
+static inline struct obj_cgroup **page_objcgs_check(struct page *page)
+{
+ return NULL;
+}
+
+static inline bool set_page_objcgs(struct page *page,
+ struct obj_cgroup **objcgs)
+{
+ return true;
+}
+#endif
+
static __always_inline bool memcg_stat_item_in_bytes(int idx)
{
if (idx == MEMCG_PERCPU_B)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 3968d68503cb..0054b4846770 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2899,7 +2899,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
if (!vec)
return -ENOMEM;
- if (cmpxchg(&page->memcg_data, 0, (unsigned long)vec | 0x1UL))
+ if (!set_page_objcgs(page, vec))
kfree(vec);
else
kmemleak_not_leak(vec);
@@ -2933,12 +2933,12 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p)
* Memcg membership data for each individual object is saved in
* the page->obj_cgroups.
*/
- if (page_has_obj_cgroups(page)) {
+ if (page_objcgs_check(page)) {
struct obj_cgroup *objcg;
unsigned int off;
off = obj_to_index(page->slab_cache, page, p);
- objcg = page_obj_cgroups(page)[off];
+ objcg = page_objcgs(page)[off];
if (objcg)
return obj_cgroup_memcg(objcg);
diff --git a/mm/slab.h b/mm/slab.h
index e2535cee0d33..9a54a0cb5cca 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -239,28 +239,12 @@ static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t fla
}
#ifdef CONFIG_MEMCG_KMEM
-static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
-{
- /*
- * Page's memory cgroup and obj_cgroups vector are sharing the same
- * space. To distinguish between them in case we don't know for sure
- * that the page is a slab page (e.g. page_cgroup_ino()), let's
- * always set the lowest bit of obj_cgroups.
- */
- return (struct obj_cgroup **)(page->memcg_data & ~0x1UL);
-}
-
-static inline bool page_has_obj_cgroups(struct page *page)
-{
- return page->memcg_data & 0x1UL;
-}
-
int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
gfp_t gfp);
static inline void memcg_free_page_obj_cgroups(struct page *page)
{
- kfree(page_obj_cgroups(page));
+ kfree(page_objcgs(page));
page->memcg_data = 0;
}
@@ -322,7 +306,7 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
if (likely(p[i])) {
page = virt_to_head_page(p[i]);
- if (!page_has_obj_cgroups(page) &&
+ if (!page_objcgs(page) &&
memcg_alloc_page_obj_cgroups(page, s, flags)) {
obj_cgroup_uncharge(objcg, obj_full_size(s));
continue;
@@ -330,7 +314,7 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
off = obj_to_index(s, page, p[i]);
obj_cgroup_get(objcg);
- page_obj_cgroups(page)[off] = objcg;
+ page_objcgs(page)[off] = objcg;
mod_objcg_state(objcg, page_pgdat(page),
cache_vmstat_idx(s), obj_full_size(s));
} else {
@@ -344,6 +328,7 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
void **p, int objects)
{
struct kmem_cache *s;
+ struct obj_cgroup **objcgs;
struct obj_cgroup *objcg;
struct page *page;
unsigned int off;
@@ -357,7 +342,8 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
continue;
page = virt_to_head_page(p[i]);
- if (!page_has_obj_cgroups(page))
+ objcgs = page_objcgs(page);
+ if (!objcgs)
continue;
if (!s_orig)
@@ -366,11 +352,11 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
s = s_orig;
off = obj_to_index(s, page, p[i]);
- objcg = page_obj_cgroups(page)[off];
+ objcg = objcgs[off];
if (!objcg)
continue;
- page_obj_cgroups(page)[off] = NULL;
+ objcgs[off] = NULL;
obj_cgroup_uncharge(objcg, obj_full_size(s));
mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s),
-obj_full_size(s));
@@ -379,11 +365,6 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
}
#else /* CONFIG_MEMCG_KMEM */
-static inline bool page_has_obj_cgroups(struct page *page)
-{
- return false;
-}
-
static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr)
{
return NULL;
--
2.26.2
Do not use rlimit-based memory accounting for stackmap maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/stackmap.c | 16 +++-------------
1 file changed, 3 insertions(+), 13 deletions(-)
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 06065fa27124..3325add8e629 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -90,7 +90,6 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
{
u32 value_size = attr->value_size;
struct bpf_stack_map *smap;
- struct bpf_map_memory mem;
u64 cost, n_buckets;
int err;
@@ -119,15 +118,9 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
cost = n_buckets * sizeof(struct stack_map_bucket *) + sizeof(*smap);
cost += n_buckets * (value_size + sizeof(struct stack_map_bucket));
- err = bpf_map_charge_init(&mem, cost);
- if (err)
- return ERR_PTR(err);
-
smap = bpf_map_area_alloc(cost, bpf_map_attr_numa_node(attr));
- if (!smap) {
- bpf_map_charge_finish(&mem);
+ if (!smap)
return ERR_PTR(-ENOMEM);
- }
bpf_map_init_from_attr(&smap->map, attr);
smap->map.value_size = value_size;
@@ -135,20 +128,17 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
err = get_callchain_buffers(sysctl_perf_event_max_stack);
if (err)
- goto free_charge;
+ goto free_smap;
err = prealloc_elems_and_freelist(smap);
if (err)
goto put_buffers;
- bpf_map_charge_move(&smap->map.memory, &mem);
-
return &smap->map;
put_buffers:
put_callchain_buffers();
-free_charge:
- bpf_map_charge_finish(&mem);
+free_smap:
bpf_map_area_free(smap);
return ERR_PTR(err);
}
--
2.26.2
Include metadata and percpu data into the memcg-based memory
accounting. Switch allocations made from an update path to
new bpf_map_* allocation helpers to make the accounting work
properly from an interrupt context.
Signed-off-by: Roman Gushchin <[email protected]>
---
kernel/bpf/cpumap.c | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index c61a23b564aa..e6b234d5e3a8 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -97,7 +97,7 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr)
attr->map_flags & ~BPF_F_NUMA_NODE)
return ERR_PTR(-EINVAL);
- cmap = kzalloc(sizeof(*cmap), GFP_USER);
+ cmap = kzalloc(sizeof(*cmap), GFP_USER | __GFP_ACCOUNT);
if (!cmap)
return ERR_PTR(-ENOMEM);
@@ -412,23 +412,24 @@ static int __cpu_map_load_bpf_program(struct bpf_cpu_map_entry *rcpu, int fd)
}
static struct bpf_cpu_map_entry *
-__cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
+__cpu_map_entry_alloc(struct bpf_map *map, struct bpf_cpumap_val *value,
+ u32 cpu)
{
int numa, err, i, fd = value->bpf_prog.fd;
- gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
+ gfp_t gfp = __GFP_ZERO | GFP_KERNEL_ACCOUNT | __GFP_NOWARN;
struct bpf_cpu_map_entry *rcpu;
struct xdp_bulk_queue *bq;
/* Have map->numa_node, but choose node of redirect target CPU */
numa = cpu_to_node(cpu);
- rcpu = kzalloc_node(sizeof(*rcpu), gfp, numa);
+ rcpu = bpf_map_kmalloc_node(map, sizeof(*rcpu), gfp, numa);
if (!rcpu)
return NULL;
/* Alloc percpu bulkq */
- rcpu->bulkq = __alloc_percpu_gfp(sizeof(*rcpu->bulkq),
- sizeof(void *), gfp);
+ rcpu->bulkq = bpf_map_alloc_percpu(map, sizeof(*rcpu->bulkq),
+ sizeof(void *), gfp);
if (!rcpu->bulkq)
goto free_rcu;
@@ -438,7 +439,8 @@ __cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
}
/* Alloc queue */
- rcpu->queue = kzalloc_node(sizeof(*rcpu->queue), gfp, numa);
+ rcpu->queue = bpf_map_kmalloc_node(map, sizeof(*rcpu->queue), gfp,
+ numa);
if (!rcpu->queue)
goto free_bulkq;
@@ -447,7 +449,7 @@ __cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
goto free_queue;
rcpu->cpu = cpu;
- rcpu->map_id = map_id;
+ rcpu->map_id = map->id;
rcpu->value.qsize = value->qsize;
if (fd > 0 && __cpu_map_load_bpf_program(rcpu, fd))
@@ -455,7 +457,8 @@ __cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
/* Setup kthread */
rcpu->kthread = kthread_create_on_node(cpu_map_kthread_run, rcpu, numa,
- "cpumap/%d/map:%d", cpu, map_id);
+ "cpumap/%d/map:%d", cpu,
+ map->id);
if (IS_ERR(rcpu->kthread))
goto free_prog;
@@ -571,7 +574,7 @@ static int cpu_map_update_elem(struct bpf_map *map, void *key, void *value,
rcpu = NULL; /* Same as deleting */
} else {
/* Updating qsize cause re-allocation of bpf_cpu_map_entry */
- rcpu = __cpu_map_entry_alloc(&cpumap_value, key_cpu, map->id);
+ rcpu = __cpu_map_entry_alloc(map, &cpumap_value, key_cpu);
if (!rcpu)
return -ENOMEM;
rcpu->cmap = cmap;
--
2.26.2
Enable the memcg-based memory accounting for the memory used by
the bpf ringbuffer.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/ringbuf.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c
index 31cb04a4dd2d..ee5f55d9276e 100644
--- a/kernel/bpf/ringbuf.c
+++ b/kernel/bpf/ringbuf.c
@@ -60,8 +60,8 @@ struct bpf_ringbuf_hdr {
static struct bpf_ringbuf *bpf_ringbuf_area_alloc(size_t data_sz, int numa_node)
{
- const gfp_t flags = GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN |
- __GFP_ZERO;
+ const gfp_t flags = GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL |
+ __GFP_NOWARN | __GFP_ZERO;
int nr_meta_pages = RINGBUF_PGOFF + RINGBUF_POS_PAGES;
int nr_data_pages = data_sz >> PAGE_SHIFT;
int nr_pages = nr_meta_pages + nr_data_pages;
@@ -89,7 +89,8 @@ static struct bpf_ringbuf *bpf_ringbuf_area_alloc(size_t data_sz, int numa_node)
*/
array_size = (nr_meta_pages + 2 * nr_data_pages) * sizeof(*pages);
if (array_size > PAGE_SIZE)
- pages = vmalloc_node(array_size, numa_node);
+ pages = __vmalloc_node(array_size, 1, GFP_KERNEL_ACCOUNT,
+ numa_node, __builtin_return_address(0));
else
pages = kmalloc_node(array_size, flags, numa_node);
if (!pages)
@@ -167,7 +168,7 @@ static struct bpf_map *ringbuf_map_alloc(union bpf_attr *attr)
return ERR_PTR(-E2BIG);
#endif
- rb_map = kzalloc(sizeof(*rb_map), GFP_USER);
+ rb_map = kzalloc(sizeof(*rb_map), GFP_USER | __GFP_ACCOUNT);
if (!rb_map)
return ERR_PTR(-ENOMEM);
--
2.26.2
Include percpu objects and the size of map metadata into the
accounting.
Signed-off-by: Roman Gushchin <[email protected]>
---
kernel/bpf/hashtab.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index ec46266aaf1c..2b8bbdbec872 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -292,7 +292,8 @@ static int prealloc_init(struct bpf_htab *htab)
u32 size = round_up(htab->map.value_size, 8);
void __percpu *pptr;
- pptr = __alloc_percpu_gfp(size, 8, GFP_USER | __GFP_NOWARN);
+ pptr = __alloc_percpu_gfp(size, 8, GFP_USER | __GFP_NOWARN |
+ __GFP_ACCOUNT);
if (!pptr)
goto free_elems;
htab_elem_set_ptr(get_htab_elem(htab, i), htab->map.key_size,
@@ -347,7 +348,7 @@ static int alloc_extra_elems(struct bpf_htab *htab)
int cpu;
pptr = __alloc_percpu_gfp(sizeof(struct htab_elem *), 8,
- GFP_USER | __GFP_NOWARN);
+ GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
if (!pptr)
return -ENOMEM;
@@ -444,7 +445,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
int err, i;
u64 cost;
- htab = kzalloc(sizeof(*htab), GFP_USER);
+ htab = kzalloc(sizeof(*htab), GFP_USER | __GFP_ACCOUNT);
if (!htab)
return ERR_PTR(-ENOMEM);
@@ -892,6 +893,7 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
bool percpu, bool onallcpus,
struct htab_elem *old_elem)
{
+ const gfp_t gfp = GFP_ATOMIC | __GFP_NOWARN | __GFP_ACCOUNT;
u32 size = htab->map.value_size;
bool prealloc = htab_is_prealloc(htab);
struct htab_elem *l_new, **pl_new;
@@ -925,8 +927,8 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
l_new = ERR_PTR(-E2BIG);
goto dec_count;
}
- l_new = kmalloc_node(htab->elem_size, GFP_ATOMIC | __GFP_NOWARN,
- htab->map.numa_node);
+ l_new = bpf_map_kmalloc_node(&htab->map, htab->elem_size, gfp,
+ htab->map.numa_node);
if (!l_new) {
l_new = ERR_PTR(-ENOMEM);
goto dec_count;
@@ -942,8 +944,7 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
pptr = htab_elem_get_ptr(l_new, key_size);
} else {
/* alloc_percpu zero-fills */
- pptr = __alloc_percpu_gfp(size, 8,
- GFP_ATOMIC | __GFP_NOWARN);
+ pptr = bpf_map_alloc_percpu(&htab->map, size, 8, gfp);
if (!pptr) {
kfree(l_new);
l_new = ERR_PTR(-ENOMEM);
--
2.26.2
Do not use rlimit-based memory accounting for bpf progs. It has been
replaced with memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
include/linux/bpf.h | 11 -------
kernel/bpf/core.c | 12 ++------
kernel/bpf/syscall.c | 69 +++++++-------------------------------------
3 files changed, 12 insertions(+), 80 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index c9322adedd50..df5d5a8763db 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1201,8 +1201,6 @@ void bpf_prog_sub(struct bpf_prog *prog, int i);
void bpf_prog_inc(struct bpf_prog *prog);
struct bpf_prog * __must_check bpf_prog_inc_not_zero(struct bpf_prog *prog);
void bpf_prog_put(struct bpf_prog *prog);
-int __bpf_prog_charge(struct user_struct *user, u32 pages);
-void __bpf_prog_uncharge(struct user_struct *user, u32 pages);
void __bpf_free_used_maps(struct bpf_prog_aux *aux,
struct bpf_map **used_maps, u32 len);
@@ -1504,15 +1502,6 @@ bpf_prog_inc_not_zero(struct bpf_prog *prog)
return ERR_PTR(-EOPNOTSUPP);
}
-static inline int __bpf_prog_charge(struct user_struct *user, u32 pages)
-{
- return 0;
-}
-
-static inline void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
-{
-}
-
static inline void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
const struct bpf_link_ops *ops,
struct bpf_prog *prog)
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 2921f58c03a8..261f8692d0d2 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -221,23 +221,15 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
{
gfp_t gfp_flags = GFP_KERNEL_ACCOUNT | __GFP_ZERO | gfp_extra_flags;
struct bpf_prog *fp;
- u32 pages, delta;
- int ret;
+ u32 pages;
size = round_up(size, PAGE_SIZE);
pages = size / PAGE_SIZE;
if (pages <= fp_old->pages)
return fp_old;
- delta = pages - fp_old->pages;
- ret = __bpf_prog_charge(fp_old->aux->user, delta);
- if (ret)
- return NULL;
-
fp = __vmalloc(size, gfp_flags);
- if (fp == NULL) {
- __bpf_prog_uncharge(fp_old->aux->user, delta);
- } else {
+ if (fp) {
memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
fp->pages = pages;
fp->aux->prog = fp;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 3dadf34c3dd0..7cd5860098ee 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1641,51 +1641,6 @@ static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
audit_log_end(ab);
}
-int __bpf_prog_charge(struct user_struct *user, u32 pages)
-{
- unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
- unsigned long user_bufs;
-
- if (user) {
- user_bufs = atomic_long_add_return(pages, &user->locked_vm);
- if (user_bufs > memlock_limit) {
- atomic_long_sub(pages, &user->locked_vm);
- return -EPERM;
- }
- }
-
- return 0;
-}
-
-void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
-{
- if (user)
- atomic_long_sub(pages, &user->locked_vm);
-}
-
-static int bpf_prog_charge_memlock(struct bpf_prog *prog)
-{
- struct user_struct *user = get_current_user();
- int ret;
-
- ret = __bpf_prog_charge(user, prog->pages);
- if (ret) {
- free_uid(user);
- return ret;
- }
-
- prog->aux->user = user;
- return 0;
-}
-
-static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
-{
- struct user_struct *user = prog->aux->user;
-
- __bpf_prog_uncharge(user, prog->pages);
- free_uid(user);
-}
-
static int bpf_prog_alloc_id(struct bpf_prog *prog)
{
int id;
@@ -1735,7 +1690,7 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu)
kvfree(aux->func_info);
kfree(aux->func_info_aux);
- bpf_prog_uncharge_memlock(aux->prog);
+ free_uid(aux->user);
security_bpf_prog_free(aux);
bpf_prog_free(aux->prog);
}
@@ -2173,7 +2128,7 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
dst_prog = bpf_prog_get(attr->attach_prog_fd);
if (IS_ERR(dst_prog)) {
err = PTR_ERR(dst_prog);
- goto free_prog_nouncharge;
+ goto free_prog;
}
prog->aux->dst_prog = dst_prog;
}
@@ -2183,18 +2138,15 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
err = security_bpf_prog_alloc(prog->aux);
if (err)
- goto free_prog_nouncharge;
-
- err = bpf_prog_charge_memlock(prog);
- if (err)
- goto free_prog_sec;
+ goto free_prog;
+ prog->aux->user = get_current_user();
prog->len = attr->insn_cnt;
err = -EFAULT;
if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
bpf_prog_insn_size(prog)) != 0)
- goto free_prog;
+ goto free_prog_sec;
prog->orig_prog = NULL;
prog->jited = 0;
@@ -2205,19 +2157,19 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
if (bpf_prog_is_dev_bound(prog->aux)) {
err = bpf_prog_offload_init(prog, attr);
if (err)
- goto free_prog;
+ goto free_prog_sec;
}
/* find program type: socket_filter vs tracing_filter */
err = find_prog_type(type, prog);
if (err < 0)
- goto free_prog;
+ goto free_prog_sec;
prog->aux->load_time = ktime_get_boottime_ns();
err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
sizeof(attr->prog_name));
if (err < 0)
- goto free_prog;
+ goto free_prog_sec;
/* run eBPF verifier */
err = bpf_check(&prog, attr, uattr);
@@ -2262,11 +2214,10 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
*/
__bpf_prog_put_noref(prog, prog->aux->func_cnt);
return err;
-free_prog:
- bpf_prog_uncharge_memlock(prog);
free_prog_sec:
+ free_uid(prog->aux->user);
security_bpf_prog_free(prog->aux);
-free_prog_nouncharge:
+free_prog:
bpf_prog_free(prog);
return err;
}
--
2.26.2
This patch enables memcg-based memory accounting for memory allocated
by __bpf_map_area_alloc(), which is used by many types of bpf maps for
large memory allocations.
Following patches in the series will refine the accounting for
some of the map types.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/syscall.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 4154c616788c..4b514bb5cd70 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -281,7 +281,7 @@ static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
* __GFP_RETRY_MAYFAIL to avoid such situations.
*/
- const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO;
+ const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
unsigned int flags = 0;
unsigned long align = 1;
void *area;
--
2.26.2
Remove rlimit-based accounting infrastructure code, which is not used
anymore.
To provide a backward compatibility, use an approximation of the
bpf map memory footprint as a "memlock" value, available to a user
via map info. The approximation is based on the maximal number of
elements and key and value sizes.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
include/linux/bpf.h | 12 ---
kernel/bpf/syscall.c | 94 +++----------------
.../selftests/bpf/progs/bpf_iter_bpf_map.c | 2 +-
.../selftests/bpf/progs/map_ptr_kern.c | 7 --
4 files changed, 16 insertions(+), 99 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index b11436cb9e3d..c9322adedd50 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -137,11 +137,6 @@ struct bpf_map_ops {
const struct bpf_iter_seq_info *iter_seq_info;
};
-struct bpf_map_memory {
- u32 pages;
- struct user_struct *user;
-};
-
struct bpf_map {
/* The first two cachelines with read-mostly members of which some
* are also accessed in fast-path (e.g. ops, max_entries).
@@ -162,7 +157,6 @@ struct bpf_map {
u32 btf_key_type_id;
u32 btf_value_type_id;
struct btf *btf;
- struct bpf_map_memory memory;
#ifdef CONFIG_MEMCG_KMEM
struct mem_cgroup *memcg;
#endif
@@ -1223,12 +1217,6 @@ void bpf_map_inc_with_uref(struct bpf_map *map);
struct bpf_map * __must_check bpf_map_inc_not_zero(struct bpf_map *map);
void bpf_map_put_with_uref(struct bpf_map *map);
void bpf_map_put(struct bpf_map *map);
-int bpf_map_charge_memlock(struct bpf_map *map, u32 pages);
-void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages);
-int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size);
-void bpf_map_charge_finish(struct bpf_map_memory *mem);
-void bpf_map_charge_move(struct bpf_map_memory *dst,
- struct bpf_map_memory *src);
void *bpf_map_area_alloc(u64 size, int numa_node);
void *bpf_map_area_mmapable_alloc(u64 size, int numa_node);
void bpf_map_area_free(void *base);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 4b514bb5cd70..3dadf34c3dd0 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -343,77 +343,6 @@ void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
map->numa_node = bpf_map_attr_numa_node(attr);
}
-static int bpf_charge_memlock(struct user_struct *user, u32 pages)
-{
- unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
-
- if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
- atomic_long_sub(pages, &user->locked_vm);
- return -EPERM;
- }
- return 0;
-}
-
-static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
-{
- if (user)
- atomic_long_sub(pages, &user->locked_vm);
-}
-
-int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size)
-{
- u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT;
- struct user_struct *user;
- int ret;
-
- if (size >= U32_MAX - PAGE_SIZE)
- return -E2BIG;
-
- user = get_current_user();
- ret = bpf_charge_memlock(user, pages);
- if (ret) {
- free_uid(user);
- return ret;
- }
-
- mem->pages = pages;
- mem->user = user;
-
- return 0;
-}
-
-void bpf_map_charge_finish(struct bpf_map_memory *mem)
-{
- bpf_uncharge_memlock(mem->user, mem->pages);
- free_uid(mem->user);
-}
-
-void bpf_map_charge_move(struct bpf_map_memory *dst,
- struct bpf_map_memory *src)
-{
- *dst = *src;
-
- /* Make sure src will not be used for the redundant uncharging. */
- memset(src, 0, sizeof(struct bpf_map_memory));
-}
-
-int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
-{
- int ret;
-
- ret = bpf_charge_memlock(map->memory.user, pages);
- if (ret)
- return ret;
- map->memory.pages += pages;
- return ret;
-}
-
-void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
-{
- bpf_uncharge_memlock(map->memory.user, pages);
- map->memory.pages -= pages;
-}
-
static int bpf_map_alloc_id(struct bpf_map *map)
{
int id;
@@ -533,14 +462,11 @@ static void bpf_map_release_memcg(struct bpf_map *map)
static void bpf_map_free_deferred(struct work_struct *work)
{
struct bpf_map *map = container_of(work, struct bpf_map, work);
- struct bpf_map_memory mem;
- bpf_map_charge_move(&mem, &map->memory);
security_bpf_map_free(map);
bpf_map_release_memcg(map);
/* implementation dependent freeing */
map->ops->map_free(map);
- bpf_map_charge_finish(&mem);
}
static void bpf_map_put_uref(struct bpf_map *map)
@@ -601,6 +527,19 @@ static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
}
#ifdef CONFIG_PROC_FS
+/* Provides an approximation of the map's memory footprint.
+ * Used only to provide a backward compatibility and display
+ * a reasonable "memlock" info.
+ */
+static unsigned long bpf_map_memory_footprint(struct bpf_map *map)
+{
+ unsigned long size;
+
+ size = round_up(map->key_size + bpf_map_value_size(map), 8);
+
+ return round_up(map->max_entries * size, PAGE_SIZE);
+}
+
static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
{
const struct bpf_map *map = filp->private_data;
@@ -619,7 +558,7 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
"value_size:\t%u\n"
"max_entries:\t%u\n"
"map_flags:\t%#x\n"
- "memlock:\t%llu\n"
+ "memlock:\t%lu\n"
"map_id:\t%u\n"
"frozen:\t%u\n",
map->map_type,
@@ -627,7 +566,7 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
map->value_size,
map->max_entries,
map->map_flags,
- map->memory.pages * 1ULL << PAGE_SHIFT,
+ bpf_map_memory_footprint(map),
map->id,
READ_ONCE(map->frozen));
if (type) {
@@ -870,7 +809,6 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
static int map_create(union bpf_attr *attr)
{
int numa_node = bpf_map_attr_numa_node(attr);
- struct bpf_map_memory mem;
struct bpf_map *map;
int f_flags;
int err;
@@ -969,9 +907,7 @@ static int map_create(union bpf_attr *attr)
security_bpf_map_free(map);
free_map:
btf_put(map->btf);
- bpf_map_charge_move(&mem, &map->memory);
map->ops->map_free(map);
- bpf_map_charge_finish(&mem);
return err;
}
diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_map.c b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_map.c
index 08651b23edba..b83b5d2e17dc 100644
--- a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_map.c
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_map.c
@@ -23,6 +23,6 @@ int dump_bpf_map(struct bpf_iter__bpf_map *ctx)
BPF_SEQ_PRINTF(seq, "%8u %8ld %8ld %10lu\n", map->id, map->refcnt.counter,
map->usercnt.counter,
- map->memory.user->locked_vm.counter);
+ 0LLU);
return 0;
}
diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
index c325405751e2..d8850bc6a9f1 100644
--- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c
+++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
@@ -26,17 +26,12 @@ __u32 g_line = 0;
return 0; \
})
-struct bpf_map_memory {
- __u32 pages;
-} __attribute__((preserve_access_index));
-
struct bpf_map {
enum bpf_map_type map_type;
__u32 key_size;
__u32 value_size;
__u32 max_entries;
__u32 id;
- struct bpf_map_memory memory;
} __attribute__((preserve_access_index));
static inline int check_bpf_map_fields(struct bpf_map *map, __u32 key_size,
@@ -47,7 +42,6 @@ static inline int check_bpf_map_fields(struct bpf_map *map, __u32 key_size,
VERIFY(map->value_size == value_size);
VERIFY(map->max_entries == max_entries);
VERIFY(map->id > 0);
- VERIFY(map->memory.pages > 0);
return 1;
}
@@ -60,7 +54,6 @@ static inline int check_bpf_map_ptr(struct bpf_map *indirect,
VERIFY(indirect->value_size == direct->value_size);
VERIFY(indirect->max_entries == direct->max_entries);
VERIFY(indirect->id == direct->id);
- VERIFY(indirect->memory.pages == direct->memory.pages);
return 1;
}
--
2.26.2
Do not use rlimit-based memory accounting for arraymap maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/arraymap.c | 24 ++++--------------------
1 file changed, 4 insertions(+), 20 deletions(-)
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 92b650123c22..20f751a1d993 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -81,11 +81,10 @@ int array_map_alloc_check(union bpf_attr *attr)
static struct bpf_map *array_map_alloc(union bpf_attr *attr)
{
bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
- int ret, numa_node = bpf_map_attr_numa_node(attr);
+ int numa_node = bpf_map_attr_numa_node(attr);
u32 elem_size, index_mask, max_entries;
bool bypass_spec_v1 = bpf_bypass_spec_v1();
- u64 cost, array_size, mask64;
- struct bpf_map_memory mem;
+ u64 array_size, mask64;
struct bpf_array *array;
elem_size = round_up(attr->value_size, 8);
@@ -126,44 +125,29 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
}
}
- /* make sure there is no u32 overflow later in round_up() */
- cost = array_size;
- if (percpu)
- cost += (u64)attr->max_entries * elem_size * num_possible_cpus();
-
- ret = bpf_map_charge_init(&mem, cost);
- if (ret < 0)
- return ERR_PTR(ret);
-
/* allocate all map elements and zero-initialize them */
if (attr->map_flags & BPF_F_MMAPABLE) {
void *data;
/* kmalloc'ed memory can't be mmap'ed, use explicit vmalloc */
data = bpf_map_area_mmapable_alloc(array_size, numa_node);
- if (!data) {
- bpf_map_charge_finish(&mem);
+ if (!data)
return ERR_PTR(-ENOMEM);
- }
array = data + PAGE_ALIGN(sizeof(struct bpf_array))
- offsetof(struct bpf_array, value);
} else {
array = bpf_map_area_alloc(array_size, numa_node);
}
- if (!array) {
- bpf_map_charge_finish(&mem);
+ if (!array)
return ERR_PTR(-ENOMEM);
- }
array->index_mask = index_mask;
array->map.bypass_spec_v1 = bypass_spec_v1;
/* copy mandatory map attributes */
bpf_map_init_from_attr(&array->map, attr);
- bpf_map_charge_move(&array->map.memory, &mem);
array->elem_size = elem_size;
if (percpu && bpf_array_alloc_percpu(array)) {
- bpf_map_charge_finish(&array->map.memory);
bpf_map_area_free(array);
return ERR_PTR(-ENOMEM);
}
--
2.26.2
Include lpm trie and lpm trie node objects into the memcg-based memory
accounting.
Signed-off-by: Roman Gushchin <[email protected]>
---
kernel/bpf/lpm_trie.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c
index 00e32f2ec3e6..a7d1e5cb80da 100644
--- a/kernel/bpf/lpm_trie.c
+++ b/kernel/bpf/lpm_trie.c
@@ -282,8 +282,9 @@ static struct lpm_trie_node *lpm_trie_node_alloc(const struct lpm_trie *trie,
if (value)
size += trie->map.value_size;
- node = kmalloc_node(size, GFP_ATOMIC | __GFP_NOWARN,
- trie->map.numa_node);
+ node = bpf_map_kmalloc_node(&trie->map, size,
+ GFP_ATOMIC | __GFP_NOWARN | __GFP_ACCOUNT,
+ trie->map.numa_node);
if (!node)
return NULL;
@@ -557,7 +558,7 @@ static struct bpf_map *trie_alloc(union bpf_attr *attr)
attr->value_size > LPM_VAL_SIZE_MAX)
return ERR_PTR(-EINVAL);
- trie = kzalloc(sizeof(*trie), GFP_USER | __GFP_NOWARN);
+ trie = kzalloc(sizeof(*trie), GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
if (!trie)
return ERR_PTR(-ENOMEM);
--
2.26.2
Do not use rlimit-based memory accounting for cpumap maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/cpumap.c | 16 +---------------
1 file changed, 1 insertion(+), 15 deletions(-)
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index e6b234d5e3a8..20e8da8a2ac2 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -84,8 +84,6 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr)
u32 value_size = attr->value_size;
struct bpf_cpu_map *cmap;
int err = -ENOMEM;
- u64 cost;
- int ret;
if (!bpf_capable())
return ERR_PTR(-EPERM);
@@ -109,26 +107,14 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr)
goto free_cmap;
}
- /* make sure page count doesn't overflow */
- cost = (u64) cmap->map.max_entries * sizeof(struct bpf_cpu_map_entry *);
-
- /* Notice returns -EPERM on if map size is larger than memlock limit */
- ret = bpf_map_charge_init(&cmap->map.memory, cost);
- if (ret) {
- err = ret;
- goto free_cmap;
- }
-
/* Alloc array for possible remote "destination" CPUs */
cmap->cpu_map = bpf_map_area_alloc(cmap->map.max_entries *
sizeof(struct bpf_cpu_map_entry *),
cmap->map.numa_node);
if (!cmap->cpu_map)
- goto free_charge;
+ goto free_cmap;
return &cmap->map;
-free_charge:
- bpf_map_charge_finish(&cmap->map.memory);
free_cmap:
kfree(cmap);
return ERR_PTR(err);
--
2.26.2
Do not use rlimit-based memory accounting for sockmap and sockhash maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
net/core/sock_map.c | 33 ++++++---------------------------
1 file changed, 6 insertions(+), 27 deletions(-)
diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 3ff635af737a..310e57f65a00 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -27,8 +27,6 @@ struct bpf_stab {
static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
{
struct bpf_stab *stab;
- u64 cost;
- int err;
if (!capable(CAP_NET_ADMIN))
return ERR_PTR(-EPERM);
@@ -46,22 +44,15 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
bpf_map_init_from_attr(&stab->map, attr);
raw_spin_lock_init(&stab->lock);
- /* Make sure page count doesn't overflow. */
- cost = (u64) stab->map.max_entries * sizeof(struct sock *);
- err = bpf_map_charge_init(&stab->map.memory, cost);
- if (err)
- goto free_stab;
-
stab->sks = bpf_map_area_alloc(stab->map.max_entries *
sizeof(struct sock *),
stab->map.numa_node);
- if (stab->sks)
- return &stab->map;
- err = -ENOMEM;
- bpf_map_charge_finish(&stab->map.memory);
-free_stab:
- kfree(stab);
- return ERR_PTR(err);
+ if (!stab->sks) {
+ kfree(stab);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return &stab->map;
}
int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog)
@@ -1104,7 +1095,6 @@ static struct bpf_map *sock_hash_alloc(union bpf_attr *attr)
{
struct bpf_shtab *htab;
int i, err;
- u64 cost;
if (!capable(CAP_NET_ADMIN))
return ERR_PTR(-EPERM);
@@ -1132,21 +1122,10 @@ static struct bpf_map *sock_hash_alloc(union bpf_attr *attr)
goto free_htab;
}
- cost = (u64) htab->buckets_num * sizeof(struct bpf_shtab_bucket) +
- (u64) htab->elem_size * htab->map.max_entries;
- if (cost >= U32_MAX - PAGE_SIZE) {
- err = -EINVAL;
- goto free_htab;
- }
- err = bpf_map_charge_init(&htab->map.memory, cost);
- if (err)
- goto free_htab;
-
htab->buckets = bpf_map_area_alloc(htab->buckets_num *
sizeof(struct bpf_shtab_bucket),
htab->map.numa_node);
if (!htab->buckets) {
- bpf_map_charge_finish(&htab->map.memory);
err = -ENOMEM;
goto free_htab;
}
--
2.26.2
Account memory used by cgroup storage maps including metadata
structures.
Account the percpu memory for the percpu flavor of cgroup storage.
Signed-off-by: Roman Gushchin <[email protected]>
---
kernel/bpf/local_storage.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index 571bb351ed3b..aae17d29538e 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -164,10 +164,10 @@ static int cgroup_storage_update_elem(struct bpf_map *map, void *key,
return 0;
}
- new = kmalloc_node(sizeof(struct bpf_storage_buffer) +
- map->value_size,
- __GFP_ZERO | GFP_ATOMIC | __GFP_NOWARN,
- map->numa_node);
+ new = bpf_map_kmalloc_node(map, sizeof(struct bpf_storage_buffer) +
+ map->value_size, __GFP_ZERO | GFP_ATOMIC |
+ __GFP_NOWARN | __GFP_ACCOUNT,
+ map->numa_node);
if (!new)
return -ENOMEM;
@@ -313,7 +313,7 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
return ERR_PTR(ret);
map = kmalloc_node(sizeof(struct bpf_cgroup_storage_map),
- __GFP_ZERO | GFP_USER, numa_node);
+ __GFP_ZERO | GFP_USER | __GFP_ACCOUNT, numa_node);
if (!map) {
bpf_map_charge_finish(&mem);
return ERR_PTR(-ENOMEM);
@@ -496,9 +496,9 @@ static size_t bpf_cgroup_storage_calculate_size(struct bpf_map *map, u32 *pages)
struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
enum bpf_cgroup_storage_type stype)
{
+ const gfp_t gfp = __GFP_ZERO | GFP_USER | __GFP_ACCOUNT;
struct bpf_cgroup_storage *storage;
struct bpf_map *map;
- gfp_t flags;
size_t size;
u32 pages;
@@ -511,20 +511,18 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
if (bpf_map_charge_memlock(map, pages))
return ERR_PTR(-EPERM);
- storage = kmalloc_node(sizeof(struct bpf_cgroup_storage),
- __GFP_ZERO | GFP_USER, map->numa_node);
+ storage = kmalloc_node(sizeof(struct bpf_cgroup_storage), gfp,
+ map->numa_node);
if (!storage)
goto enomem;
- flags = __GFP_ZERO | GFP_USER;
-
if (stype == BPF_CGROUP_STORAGE_SHARED) {
- storage->buf = kmalloc_node(size, flags, map->numa_node);
+ storage->buf = kmalloc_node(size, gfp, map->numa_node);
if (!storage->buf)
goto enomem;
check_and_init_map_lock(map, storage->buf->data);
} else {
- storage->percpu_buf = __alloc_percpu_gfp(size, 8, flags);
+ storage->percpu_buf = __alloc_percpu_gfp(size, 8, gfp);
if (!storage->percpu_buf)
goto enomem;
}
--
2.26.2
In the absolute majority of cases if a process is making a kernel
allocation, it's memory cgroup is getting charged.
Bpf maps can be updated from an interrupt context and in such
case there is no process which can be charged. It makes the memory
accounting of bpf maps non-trivial.
Fortunately, after commit 4127c6504f25 ("mm: kmem: enable kernel
memcg accounting from interrupt contexts") and b87d8cefe43c
("mm, memcg: rework remote charging API to support nesting")
it's finally possible.
To do it, a pointer to the memory cgroup of the process, which created
the map, is saved, and this cgroup can be charged for all allocations
made from an interrupt context. This commit introduces 2 helpers:
bpf_map_kmalloc_node() and bpf_map_alloc_percpu(). They can be used in
the bpf code for accounted memory allocations, both in the process and
interrupt contexts. In the interrupt context they're using the saved
memory cgroup, otherwise the current cgroup is getting charged.
Signed-off-by: Roman Gushchin <[email protected]>
---
include/linux/bpf.h | 26 +++++++++++++++
kernel/bpf/syscall.c | 76 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 102 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index e1bcb6d7345c..b11436cb9e3d 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -20,6 +20,7 @@
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/capability.h>
+#include <linux/slab.h>
struct bpf_verifier_env;
struct bpf_verifier_log;
@@ -37,6 +38,7 @@ struct bpf_iter_aux_info;
struct bpf_local_storage;
struct bpf_local_storage_map;
struct kobject;
+struct mem_cgroup;
extern struct idr btf_idr;
extern spinlock_t btf_idr_lock;
@@ -161,6 +163,9 @@ struct bpf_map {
u32 btf_value_type_id;
struct btf *btf;
struct bpf_map_memory memory;
+#ifdef CONFIG_MEMCG_KMEM
+ struct mem_cgroup *memcg;
+#endif
char name[BPF_OBJ_NAME_LEN];
u32 btf_vmlinux_value_type_id;
bool bypass_spec_v1;
@@ -1240,6 +1245,27 @@ int generic_map_delete_batch(struct bpf_map *map,
struct bpf_map *bpf_map_get_curr_or_next(u32 *id);
struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id);
+#ifdef CONFIG_MEMCG_KMEM
+void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
+ int node);
+void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
+ size_t align, gfp_t gfp);
+#else
+static inline void *
+bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
+ int node)
+{
+ return kmalloc_node(size, flags, node);
+}
+
+static inline void __percpu *
+bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, size_t align,
+ gfp_t gfp)
+{
+ return __alloc_percpu_gfp(size, align, gfp);
+}
+#endif
+
extern int sysctl_unprivileged_bpf_disabled;
static inline bool bpf_allow_ptr_leaks(void)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index f3fe9f53f93c..4154c616788c 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -31,6 +31,8 @@
#include <linux/poll.h>
#include <linux/bpf-netns.h>
#include <linux/rcupdate_trace.h>
+#include <linux/memcontrol.h>
+#include <linux/sched/mm.h>
#define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
(map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
@@ -456,6 +458,77 @@ void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
__release(&map_idr_lock);
}
+#ifdef CONFIG_MEMCG_KMEM
+static void bpf_map_save_memcg(struct bpf_map *map)
+{
+ map->memcg = get_mem_cgroup_from_mm(current->mm);
+}
+
+static void bpf_map_release_memcg(struct bpf_map *map)
+{
+ mem_cgroup_put(map->memcg);
+}
+
+void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
+ int node)
+{
+ struct mem_cgroup *old_memcg;
+ bool in_interrupt;
+ void *ptr;
+
+ /*
+ * If the memory allocation is performed from an interrupt context,
+ * the memory cgroup to charge can't be determined from the context
+ * of the current task. Instead, we charge the memory cgroup, which
+ * contained the process created the map.
+ */
+ in_interrupt = in_interrupt();
+ if (in_interrupt)
+ old_memcg = set_active_memcg(map->memcg);
+
+ ptr = kmalloc_node(size, flags, node);
+
+ if (in_interrupt)
+ set_active_memcg(old_memcg);
+
+ return ptr;
+}
+
+void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
+ size_t align, gfp_t gfp)
+{
+ struct mem_cgroup *old_memcg;
+ bool in_interrupt;
+ void *ptr;
+
+ /*
+ * If the memory allocation is performed from an interrupt context,
+ * the memory cgroup to charge can't be determined from the context
+ * of the current task. Instead, we charge the memory cgroup, which
+ * contained the process created the map.
+ */
+ in_interrupt = in_interrupt();
+ if (in_interrupt)
+ old_memcg = set_active_memcg(map->memcg);
+
+ ptr = __alloc_percpu_gfp(size, align, gfp);
+
+ if (in_interrupt)
+ set_active_memcg(old_memcg);
+
+ return ptr;
+}
+
+#else
+static void bpf_map_save_memcg(struct bpf_map *map)
+{
+}
+
+static void bpf_map_release_memcg(struct bpf_map *map)
+{
+}
+#endif
+
/* called from workqueue */
static void bpf_map_free_deferred(struct work_struct *work)
{
@@ -464,6 +537,7 @@ static void bpf_map_free_deferred(struct work_struct *work)
bpf_map_charge_move(&mem, &map->memory);
security_bpf_map_free(map);
+ bpf_map_release_memcg(map);
/* implementation dependent freeing */
map->ops->map_free(map);
bpf_map_charge_finish(&mem);
@@ -875,6 +949,8 @@ static int map_create(union bpf_attr *attr)
if (err)
goto free_map_sec;
+ bpf_map_save_memcg(map);
+
err = bpf_map_new_fd(map, f_flags);
if (err < 0) {
/* failed to allocate fd.
--
2.26.2
The lowest bit in page->memcg_data is used to distinguish between struct
memory_cgroup pointer and a pointer to a objcgs array. All checks and
modifications of this bit are open-coded.
Let's formalize it using page memcg flags, defined in enum
page_memcg_data_flags.
Additional flags might be added later.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Roman Gushchin <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
include/linux/memcontrol.h | 32 ++++++++++++++++++++------------
1 file changed, 20 insertions(+), 12 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index c7ac0a5b8989..99a4841d658b 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -343,6 +343,15 @@ struct mem_cgroup {
extern struct mem_cgroup *root_mem_cgroup;
+enum page_memcg_data_flags {
+ /* page->memcg_data is a pointer to an objcgs vector */
+ MEMCG_DATA_OBJCGS = (1UL << 0),
+ /* the next bit after the last actual flag */
+ __NR_MEMCG_DATA_FLAGS = (1UL << 1),
+};
+
+#define MEMCG_DATA_FLAGS_MASK (__NR_MEMCG_DATA_FLAGS - 1)
+
/*
* page_memcg - get the memory cgroup associated with a page
* @page: a pointer to the page struct
@@ -404,13 +413,7 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
*/
unsigned long memcg_data = READ_ONCE(page->memcg_data);
- /*
- * The lowest bit set means that memcg isn't a valid
- * memcg pointer, but a obj_cgroups pointer.
- * In this case the page is shared and doesn't belong
- * to any specific memory cgroup.
- */
- if (memcg_data & 0x1UL)
+ if (memcg_data & MEMCG_DATA_OBJCGS)
return NULL;
return (struct mem_cgroup *)memcg_data;
@@ -429,7 +432,11 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
*/
static inline struct obj_cgroup **page_objcgs(struct page *page)
{
- return (struct obj_cgroup **)(READ_ONCE(page->memcg_data) & ~0x1UL);
+ unsigned long memcg_data = READ_ONCE(page->memcg_data);
+
+ VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), page);
+
+ return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
}
/*
@@ -444,10 +451,10 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page)
{
unsigned long memcg_data = READ_ONCE(page->memcg_data);
- if (memcg_data && (memcg_data & 0x1UL))
- return (struct obj_cgroup **)(memcg_data & ~0x1UL);
+ if (!memcg_data || !(memcg_data & MEMCG_DATA_OBJCGS))
+ return NULL;
- return NULL;
+ return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
}
/*
@@ -460,7 +467,8 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page)
static inline bool set_page_objcgs(struct page *page,
struct obj_cgroup **objcgs)
{
- return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs | 0x1UL);
+ return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs |
+ MEMCG_DATA_OBJCGS);
}
#else
static inline struct obj_cgroup **page_objcgs(struct page *page)
--
2.26.2
Include memory used by bpf programs into the memcg-based accounting.
This includes the memory used by programs itself, auxiliary data,
statistics and bpf line info. A memory cgroup containing the
process which loads the program is getting charged.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/core.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index ff55cbcfbab4..2921f58c03a8 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -77,7 +77,7 @@ void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, uns
struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags)
{
- gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+ gfp_t gfp_flags = GFP_KERNEL_ACCOUNT | __GFP_ZERO | gfp_extra_flags;
struct bpf_prog_aux *aux;
struct bpf_prog *fp;
@@ -86,7 +86,7 @@ struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flag
if (fp == NULL)
return NULL;
- aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags);
+ aux = kzalloc(sizeof(*aux), GFP_KERNEL_ACCOUNT | gfp_extra_flags);
if (aux == NULL) {
vfree(fp);
return NULL;
@@ -106,7 +106,7 @@ struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flag
struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
{
- gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+ gfp_t gfp_flags = GFP_KERNEL_ACCOUNT | __GFP_ZERO | gfp_extra_flags;
struct bpf_prog *prog;
int cpu;
@@ -138,7 +138,7 @@ int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog)
prog->aux->jited_linfo = kcalloc(prog->aux->nr_linfo,
sizeof(*prog->aux->jited_linfo),
- GFP_KERNEL | __GFP_NOWARN);
+ GFP_KERNEL_ACCOUNT | __GFP_NOWARN);
if (!prog->aux->jited_linfo)
return -ENOMEM;
@@ -219,7 +219,7 @@ void bpf_prog_free_linfo(struct bpf_prog *prog)
struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
gfp_t gfp_extra_flags)
{
- gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+ gfp_t gfp_flags = GFP_KERNEL_ACCOUNT | __GFP_ZERO | gfp_extra_flags;
struct bpf_prog *fp;
u32 pages, delta;
int ret;
--
2.26.2
Do not use rlimit-based memory accounting for bpf_struct_ops maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/bpf_struct_ops.c | 19 +++----------------
1 file changed, 3 insertions(+), 16 deletions(-)
diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
index 4c3b543bb33b..1a666a975416 100644
--- a/kernel/bpf/bpf_struct_ops.c
+++ b/kernel/bpf/bpf_struct_ops.c
@@ -548,12 +548,10 @@ static int bpf_struct_ops_map_alloc_check(union bpf_attr *attr)
static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr)
{
const struct bpf_struct_ops *st_ops;
- size_t map_total_size, st_map_size;
+ size_t st_map_size;
struct bpf_struct_ops_map *st_map;
const struct btf_type *t, *vt;
- struct bpf_map_memory mem;
struct bpf_map *map;
- int err;
if (!bpf_capable())
return ERR_PTR(-EPERM);
@@ -573,20 +571,11 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr)
* struct bpf_struct_ops_tcp_congestions_ops
*/
(vt->size - sizeof(struct bpf_struct_ops_value));
- map_total_size = st_map_size +
- /* uvalue */
- sizeof(vt->size) +
- /* struct bpf_progs **progs */
- btf_type_vlen(t) * sizeof(struct bpf_prog *);
- err = bpf_map_charge_init(&mem, map_total_size);
- if (err < 0)
- return ERR_PTR(err);
st_map = bpf_map_area_alloc(st_map_size, NUMA_NO_NODE);
- if (!st_map) {
- bpf_map_charge_finish(&mem);
+ if (!st_map)
return ERR_PTR(-ENOMEM);
- }
+
st_map->st_ops = st_ops;
map = &st_map->map;
@@ -597,14 +586,12 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr)
st_map->image = bpf_jit_alloc_exec(PAGE_SIZE);
if (!st_map->uvalue || !st_map->progs || !st_map->image) {
bpf_struct_ops_map_free(map);
- bpf_map_charge_finish(&mem);
return ERR_PTR(-ENOMEM);
}
mutex_init(&st_map->lock);
set_vm_flush_reset_perms(st_map->image);
bpf_map_init_from_attr(map, attr);
- bpf_map_charge_move(&map->memory, &mem);
return map;
}
--
2.26.2
Do not use rlimit-based memory accounting for lpm_trie maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/lpm_trie.c | 13 -------------
1 file changed, 13 deletions(-)
diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c
index a7d1e5cb80da..65757321ddf8 100644
--- a/kernel/bpf/lpm_trie.c
+++ b/kernel/bpf/lpm_trie.c
@@ -541,8 +541,6 @@ static int trie_delete_elem(struct bpf_map *map, void *_key)
static struct bpf_map *trie_alloc(union bpf_attr *attr)
{
struct lpm_trie *trie;
- u64 cost = sizeof(*trie), cost_per_node;
- int ret;
if (!bpf_capable())
return ERR_PTR(-EPERM);
@@ -568,20 +566,9 @@ static struct bpf_map *trie_alloc(union bpf_attr *attr)
offsetof(struct bpf_lpm_trie_key, data);
trie->max_prefixlen = trie->data_size * 8;
- cost_per_node = sizeof(struct lpm_trie_node) +
- attr->value_size + trie->data_size;
- cost += (u64) attr->max_entries * cost_per_node;
-
- ret = bpf_map_charge_init(&trie->map.memory, cost);
- if (ret)
- goto out_err;
-
spin_lock_init(&trie->lock);
return &trie->map;
-out_err:
- kfree(trie);
- return ERR_PTR(ret);
}
static void trie_free(struct bpf_map *map)
--
2.26.2
Include percpu arrays and auxiliary data into the memcg-based memory
accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/arraymap.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index c6c81eceb68f..92b650123c22 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -30,12 +30,12 @@ static void bpf_array_free_percpu(struct bpf_array *array)
static int bpf_array_alloc_percpu(struct bpf_array *array)
{
+ const gfp_t gfp = GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT;
void __percpu *ptr;
int i;
for (i = 0; i < array->map.max_entries; i++) {
- ptr = __alloc_percpu_gfp(array->elem_size, 8,
- GFP_USER | __GFP_NOWARN);
+ ptr = __alloc_percpu_gfp(array->elem_size, 8, gfp);
if (!ptr) {
bpf_array_free_percpu(array);
return -ENOMEM;
@@ -1018,7 +1018,7 @@ static struct bpf_map *prog_array_map_alloc(union bpf_attr *attr)
struct bpf_array_aux *aux;
struct bpf_map *map;
- aux = kzalloc(sizeof(*aux), GFP_KERNEL);
+ aux = kzalloc(sizeof(*aux), GFP_KERNEL_ACCOUNT);
if (!aux)
return ERR_PTR(-ENOMEM);
--
2.26.2
Do not use rlimit-based memory accounting for xskmap maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
net/xdp/xskmap.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)
diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c
index eceea51182d9..217e224698b9 100644
--- a/net/xdp/xskmap.c
+++ b/net/xdp/xskmap.c
@@ -75,9 +75,8 @@ static void xsk_map_sock_delete(struct xdp_sock *xs,
static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
{
- struct bpf_map_memory mem;
- int err, numa_node;
struct xsk_map *m;
+ int numa_node;
u64 size;
if (!capable(CAP_NET_ADMIN))
@@ -91,18 +90,11 @@ static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
numa_node = bpf_map_attr_numa_node(attr);
size = struct_size(m, xsk_map, attr->max_entries);
- err = bpf_map_charge_init(&mem, size);
- if (err < 0)
- return ERR_PTR(err);
-
m = bpf_map_area_alloc(size, numa_node);
- if (!m) {
- bpf_map_charge_finish(&mem);
+ if (!m)
return ERR_PTR(-ENOMEM);
- }
bpf_map_init_from_attr(&m->map, attr);
- bpf_map_charge_move(&m->map.memory, &mem);
spin_lock_init(&m->lock);
return &m->map;
--
2.26.2
Patch series "mm: allow mapping accounted kernel pages to userspace", v6.
Currently a non-slab kernel page which has been charged to a memory cgroup
can't be mapped to userspace. The underlying reason is simple: PageKmemcg
flag is defined as a page type (like buddy, offline, etc), so it takes a
bit from a page->mapped counter. Pages with a type set can't be mapped to
userspace.
But in general the kmemcg flag has nothing to do with mapping to
userspace. It only means that the page has been accounted by the page
allocator, so it has to be properly uncharged on release.
Some bpf maps are mapping the vmalloc-based memory to userspace, and their
memory can't be accounted because of this implementation detail.
This patchset removes this limitation by moving the PageKmemcg flag into
one of the free bits of the page->mem_cgroup pointer. Also it formalizes
accesses to the page->mem_cgroup and page->obj_cgroups using new helpers,
adds several checks and removes a couple of obsolete functions. As the
result the code became more robust with fewer open-coded bit tricks.
This patch (of 4):
Currently there are many open-coded reads of the page->mem_cgroup pointer,
as well as a couple of read helpers, which are barely used.
It creates an obstacle on a way to reuse some bits of the pointer for
storing additional bits of information. In fact, we already do this for
slab pages, where the last bit indicates that a pointer has an attached
vector of objcg pointers instead of a regular memcg pointer.
This commits uses 2 existing helpers and introduces a new helper to
converts all read sides to calls of these helpers:
struct mem_cgroup *page_memcg(struct page *page);
struct mem_cgroup *page_memcg_rcu(struct page *page);
struct mem_cgroup *page_memcg_check(struct page *page);
page_memcg_check() is intended to be used in cases when the page can be a
slab page and have a memcg pointer pointing at objcg vector. It does
check the lowest bit, and if set, returns NULL. page_memcg() contains a
VM_BUG_ON_PAGE() check for the page not being a slab page.
To make sure nobody uses a direct access, struct page's
mem_cgroup/obj_cgroups is converted to unsigned long memcg_data.
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
fs/buffer.c | 2 +-
fs/iomap/buffered-io.c | 2 +-
include/linux/memcontrol.h | 114 ++++++++++++++++++++++++++---
include/linux/mm.h | 22 ------
include/linux/mm_types.h | 5 +-
include/trace/events/writeback.h | 2 +-
kernel/fork.c | 7 +-
mm/debug.c | 4 +-
mm/huge_memory.c | 4 +-
mm/memcontrol.c | 121 ++++++++++++++-----------------
mm/page_alloc.c | 4 +-
mm/page_io.c | 6 +-
mm/slab.h | 9 +--
mm/workingset.c | 2 +-
14 files changed, 184 insertions(+), 120 deletions(-)
diff --git a/fs/buffer.c b/fs/buffer.c
index 23f645657488..b56f99f82b5b 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -657,7 +657,7 @@ int __set_page_dirty_buffers(struct page *page)
} while (bh != head);
}
/*
- * Lock out page->mem_cgroup migration to keep PageDirty
+ * Lock out page's memcg migration to keep PageDirty
* synchronized with per-memcg dirty page counters.
*/
lock_page_memcg(page);
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 10cc7979ce38..16a1e82e3aeb 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -650,7 +650,7 @@ iomap_set_page_dirty(struct page *page)
return !TestSetPageDirty(page);
/*
- * Lock out page->mem_cgroup migration to keep PageDirty
+ * Lock out page's memcg migration to keep PageDirty
* synchronized with per-memcg dirty page counters.
*/
lock_page_memcg(page);
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index e391e3c56de5..f95c1433461c 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -343,6 +343,79 @@ struct mem_cgroup {
extern struct mem_cgroup *root_mem_cgroup;
+/*
+ * page_memcg - get the memory cgroup associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the memory cgroup associated with the page,
+ * or NULL. This function assumes that the page is known to have a
+ * proper memory cgroup pointer. It's not safe to call this function
+ * against some type of pages, e.g. slab pages or ex-slab pages.
+ *
+ * Any of the following ensures page and memcg binding stability:
+ * - the page lock
+ * - LRU isolation
+ * - lock_page_memcg()
+ * - exclusive reference
+ */
+static inline struct mem_cgroup *page_memcg(struct page *page)
+{
+ VM_BUG_ON_PAGE(PageSlab(page), page);
+ return (struct mem_cgroup *)page->memcg_data;
+}
+
+/*
+ * page_memcg_rcu - locklessly get the memory cgroup associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the memory cgroup associated with the page,
+ * or NULL. This function assumes that the page is known to have a
+ * proper memory cgroup pointer. It's not safe to call this function
+ * against some type of pages, e.g. slab pages or ex-slab pages.
+ */
+static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
+{
+ VM_BUG_ON_PAGE(PageSlab(page), page);
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ return (struct mem_cgroup *)READ_ONCE(page->memcg_data);
+}
+
+/*
+ * page_memcg_check - get the memory cgroup associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the memory cgroup associated with the page,
+ * or NULL. This function unlike page_memcg() can take any page
+ * as an argument. It has to be used in cases when it's not known if a page
+ * has an associated memory cgroup pointer or an object cgroups vector.
+ *
+ * Any of the following ensures page and memcg binding stability:
+ * - the page lock
+ * - LRU isolation
+ * - lock_page_memcg()
+ * - exclusive reference
+ */
+static inline struct mem_cgroup *page_memcg_check(struct page *page)
+{
+ /*
+ * Because page->memcg_data might be changed asynchronously
+ * for slab pages, READ_ONCE() should be used here.
+ */
+ unsigned long memcg_data = READ_ONCE(page->memcg_data);
+
+ /*
+ * The lowest bit set means that memcg isn't a valid
+ * memcg pointer, but a obj_cgroups pointer.
+ * In this case the page is shared and doesn't belong
+ * to any specific memory cgroup.
+ */
+ if (memcg_data & 0x1UL)
+ return NULL;
+
+ return (struct mem_cgroup *)memcg_data;
+}
+
static __always_inline bool memcg_stat_item_in_bytes(int idx)
{
if (idx == MEMCG_PERCPU_B)
@@ -743,15 +816,19 @@ static inline void mod_memcg_state(struct mem_cgroup *memcg,
static inline void __mod_memcg_page_state(struct page *page,
int idx, int val)
{
- if (page->mem_cgroup)
- __mod_memcg_state(page->mem_cgroup, idx, val);
+ struct mem_cgroup *memcg = page_memcg(page);
+
+ if (memcg)
+ __mod_memcg_state(memcg, idx, val);
}
static inline void mod_memcg_page_state(struct page *page,
int idx, int val)
{
- if (page->mem_cgroup)
- mod_memcg_state(page->mem_cgroup, idx, val);
+ struct mem_cgroup *memcg = page_memcg(page);
+
+ if (memcg)
+ mod_memcg_state(memcg, idx, val);
}
static inline unsigned long lruvec_page_state(struct lruvec *lruvec,
@@ -834,16 +911,17 @@ static inline void __mod_lruvec_page_state(struct page *page,
enum node_stat_item idx, int val)
{
struct page *head = compound_head(page); /* rmap on tail pages */
+ struct mem_cgroup *memcg = page_memcg(head);
pg_data_t *pgdat = page_pgdat(page);
struct lruvec *lruvec;
/* Untracked pages have no memcg, no lruvec. Update only the node */
- if (!head->mem_cgroup) {
+ if (!memcg) {
__mod_node_page_state(pgdat, idx, val);
return;
}
- lruvec = mem_cgroup_lruvec(head->mem_cgroup, pgdat);
+ lruvec = mem_cgroup_lruvec(memcg, pgdat);
__mod_lruvec_state(lruvec, idx, val);
}
@@ -878,8 +956,10 @@ static inline void count_memcg_events(struct mem_cgroup *memcg,
static inline void count_memcg_page_event(struct page *page,
enum vm_event_item idx)
{
- if (page->mem_cgroup)
- count_memcg_events(page->mem_cgroup, idx, 1);
+ struct mem_cgroup *memcg = page_memcg(page);
+
+ if (memcg)
+ count_memcg_events(memcg, idx, 1);
}
static inline void count_memcg_event_mm(struct mm_struct *mm,
@@ -941,6 +1021,22 @@ void mem_cgroup_split_huge_fixup(struct page *head);
struct mem_cgroup;
+static inline struct mem_cgroup *page_memcg(struct page *page)
+{
+ return NULL;
+}
+
+static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
+{
+ WARN_ON_ONCE(!rcu_read_lock_held());
+ return NULL;
+}
+
+static inline struct mem_cgroup *page_memcg_check(struct page *page)
+{
+ return NULL;
+}
+
static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
{
return true;
@@ -1430,7 +1526,7 @@ static inline void mem_cgroup_track_foreign_dirty(struct page *page,
if (mem_cgroup_disabled())
return;
- if (unlikely(&page->mem_cgroup->css != wb->memcg_css))
+ if (unlikely(&page_memcg(page)->css != wb->memcg_css))
mem_cgroup_track_foreign_dirty_slowpath(page, wb);
}
diff --git a/include/linux/mm.h b/include/linux/mm.h
index db6ae4d3fb4e..6b0c9d2c1d10 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1484,28 +1484,6 @@ static inline void set_page_links(struct page *page, enum zone_type zone,
#endif
}
-#ifdef CONFIG_MEMCG
-static inline struct mem_cgroup *page_memcg(struct page *page)
-{
- return page->mem_cgroup;
-}
-static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
-{
- WARN_ON_ONCE(!rcu_read_lock_held());
- return READ_ONCE(page->mem_cgroup);
-}
-#else
-static inline struct mem_cgroup *page_memcg(struct page *page)
-{
- return NULL;
-}
-static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
-{
- WARN_ON_ONCE(!rcu_read_lock_held());
- return NULL;
-}
-#endif
-
/*
* Some inline functions in vmstat.h depend on page_zone()
*/
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 5a9238f6caad..80f5d755c037 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -199,10 +199,7 @@ struct page {
atomic_t _refcount;
#ifdef CONFIG_MEMCG
- union {
- struct mem_cgroup *mem_cgroup;
- struct obj_cgroup **obj_cgroups;
- };
+ unsigned long memcg_data;
#endif
/*
diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index e7cbccc7c14c..39a40dfb578a 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -257,7 +257,7 @@ TRACE_EVENT(track_foreign_dirty,
__entry->ino = inode ? inode->i_ino : 0;
__entry->memcg_id = wb->memcg_css->id;
__entry->cgroup_ino = __trace_wb_assign_cgroup(wb);
- __entry->page_cgroup_ino = cgroup_ino(page->mem_cgroup->css.cgroup);
+ __entry->page_cgroup_ino = cgroup_ino(page_memcg(page)->css.cgroup);
),
TP_printk("bdi %s[%llu]: ino=%lu memcg_id=%u cgroup_ino=%lu page_cgroup_ino=%lu",
diff --git a/kernel/fork.c b/kernel/fork.c
index 6d266388d380..cbd4f6f58409 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -404,9 +404,10 @@ static int memcg_charge_kernel_stack(struct task_struct *tsk)
for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) {
/*
- * If memcg_kmem_charge_page() fails, page->mem_cgroup
- * pointer is NULL, and memcg_kmem_uncharge_page() in
- * free_thread_stack() will ignore this page.
+ * If memcg_kmem_charge_page() fails, page's
+ * memory cgroup pointer is NULL, and
+ * memcg_kmem_uncharge_page() in free_thread_stack()
+ * will ignore this page.
*/
ret = memcg_kmem_charge_page(vm->pages[i], GFP_KERNEL,
0);
diff --git a/mm/debug.c b/mm/debug.c
index ccca576b2899..8a40b3fefbeb 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -182,8 +182,8 @@ void __dump_page(struct page *page, const char *reason)
pr_warn("page dumped because: %s\n", reason);
#ifdef CONFIG_MEMCG
- if (!page_poisoned && page->mem_cgroup)
- pr_warn("page->mem_cgroup:%px\n", page->mem_cgroup);
+ if (!page_poisoned && page->memcg_data)
+ pr_warn("pages's memcg:%lx\n", page->memcg_data);
#endif
}
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 9474dbc150ed..cedfb3503411 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -470,7 +470,7 @@ pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma)
#ifdef CONFIG_MEMCG
static inline struct deferred_split *get_deferred_split_queue(struct page *page)
{
- struct mem_cgroup *memcg = compound_head(page)->mem_cgroup;
+ struct mem_cgroup *memcg = page_memcg(compound_head(page));
struct pglist_data *pgdat = NODE_DATA(page_to_nid(page));
if (memcg)
@@ -2765,7 +2765,7 @@ void deferred_split_huge_page(struct page *page)
{
struct deferred_split *ds_queue = get_deferred_split_queue(page);
#ifdef CONFIG_MEMCG
- struct mem_cgroup *memcg = compound_head(page)->mem_cgroup;
+ struct mem_cgroup *memcg = page_memcg(compound_head(page));
#endif
unsigned long flags;
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 3dcbf24d2227..3968d68503cb 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -533,7 +533,7 @@ struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page)
{
struct mem_cgroup *memcg;
- memcg = page->mem_cgroup;
+ memcg = page_memcg(page);
if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
memcg = root_mem_cgroup;
@@ -560,16 +560,7 @@ ino_t page_cgroup_ino(struct page *page)
unsigned long ino = 0;
rcu_read_lock();
- memcg = page->mem_cgroup;
-
- /*
- * The lowest bit set means that memcg isn't a valid
- * memcg pointer, but a obj_cgroups pointer.
- * In this case the page is shared and doesn't belong
- * to any specific memory cgroup.
- */
- if ((unsigned long) memcg & 0x1UL)
- memcg = NULL;
+ memcg = page_memcg_check(page);
while (memcg && !(memcg->css.flags & CSS_ONLINE))
memcg = parent_mem_cgroup(memcg);
@@ -1050,7 +1041,7 @@ EXPORT_SYMBOL(get_mem_cgroup_from_mm);
*/
struct mem_cgroup *get_mem_cgroup_from_page(struct page *page)
{
- struct mem_cgroup *memcg = page->mem_cgroup;
+ struct mem_cgroup *memcg = page_memcg(page);
if (mem_cgroup_disabled())
return NULL;
@@ -1349,7 +1340,7 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgd
goto out;
}
- memcg = page->mem_cgroup;
+ memcg = page_memcg(page);
/*
* Swapcache readahead pages are added to the LRU - and
* possibly migrated - before they are charged.
@@ -2109,7 +2100,7 @@ void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
}
/**
- * lock_page_memcg - lock a page->mem_cgroup binding
+ * lock_page_memcg - lock a page and memcg binding
* @page: the page
*
* This function protects unlocked LRU pages from being moved to
@@ -2141,7 +2132,7 @@ struct mem_cgroup *lock_page_memcg(struct page *page)
if (mem_cgroup_disabled())
return NULL;
again:
- memcg = head->mem_cgroup;
+ memcg = page_memcg(head);
if (unlikely(!memcg))
return NULL;
@@ -2149,7 +2140,7 @@ struct mem_cgroup *lock_page_memcg(struct page *page)
return memcg;
spin_lock_irqsave(&memcg->move_lock, flags);
- if (memcg != head->mem_cgroup) {
+ if (memcg != page_memcg(head)) {
spin_unlock_irqrestore(&memcg->move_lock, flags);
goto again;
}
@@ -2187,14 +2178,14 @@ void __unlock_page_memcg(struct mem_cgroup *memcg)
}
/**
- * unlock_page_memcg - unlock a page->mem_cgroup binding
+ * unlock_page_memcg - unlock a page and memcg binding
* @page: the page
*/
void unlock_page_memcg(struct page *page)
{
struct page *head = compound_head(page);
- __unlock_page_memcg(head->mem_cgroup);
+ __unlock_page_memcg(page_memcg(head));
}
EXPORT_SYMBOL(unlock_page_memcg);
@@ -2884,7 +2875,7 @@ static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages)
static void commit_charge(struct page *page, struct mem_cgroup *memcg)
{
- VM_BUG_ON_PAGE(page->mem_cgroup, page);
+ VM_BUG_ON_PAGE(page_memcg(page), page);
/*
* Any of the following ensures page->mem_cgroup stability:
*
@@ -2893,7 +2884,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg)
* - lock_page_memcg()
* - exclusive reference
*/
- page->mem_cgroup = memcg;
+ page->memcg_data = (unsigned long)memcg;
}
#ifdef CONFIG_MEMCG_KMEM
@@ -2908,8 +2899,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
if (!vec)
return -ENOMEM;
- if (cmpxchg(&page->obj_cgroups, NULL,
- (struct obj_cgroup **) ((unsigned long)vec | 0x1UL)))
+ if (cmpxchg(&page->memcg_data, 0, (unsigned long)vec | 0x1UL))
kfree(vec);
else
kmemleak_not_leak(vec);
@@ -2920,6 +2910,12 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
/*
* Returns a pointer to the memory cgroup to which the kernel object is charged.
*
+ * A passed kernel object can be a slab object or a generic kernel page, so
+ * different mechanisms for getting the memory cgroup pointer should be used.
+ * In certain cases (e.g. kernel stacks or large kmallocs with SLUB) the caller
+ * can not know for sure how the kernel object is implemented.
+ * mem_cgroup_from_obj() can be safely used in such cases.
+ *
* The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(),
* cgroup_mutex, etc.
*/
@@ -2932,17 +2928,6 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p)
page = virt_to_head_page(p);
- /*
- * If page->mem_cgroup is set, it's either a simple mem_cgroup pointer
- * or a pointer to obj_cgroup vector. In the latter case the lowest
- * bit of the pointer is set.
- * The page->mem_cgroup pointer can be asynchronously changed
- * from NULL to (obj_cgroup_vec | 0x1UL), but can't be changed
- * from a valid memcg pointer to objcg vector or back.
- */
- if (!page->mem_cgroup)
- return NULL;
-
/*
* Slab objects are accounted individually, not per-page.
* Memcg membership data for each individual object is saved in
@@ -2960,8 +2945,14 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p)
return NULL;
}
- /* All other pages use page->mem_cgroup */
- return page->mem_cgroup;
+ /*
+ * page_memcg_check() is used here, because page_has_obj_cgroups()
+ * check above could fail because the object cgroups vector wasn't set
+ * at that moment, but it can be set concurrently.
+ * page_memcg_check(page) will guarantee that a proper memory
+ * cgroup pointer or NULL will be returned.
+ */
+ return page_memcg_check(page);
}
__always_inline struct obj_cgroup *get_obj_cgroup_from_current(void)
@@ -3099,7 +3090,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
if (memcg && !mem_cgroup_is_root(memcg)) {
ret = __memcg_kmem_charge(memcg, gfp, 1 << order);
if (!ret) {
- page->mem_cgroup = memcg;
+ page->memcg_data = (unsigned long)memcg;
__SetPageKmemcg(page);
return 0;
}
@@ -3115,7 +3106,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
*/
void __memcg_kmem_uncharge_page(struct page *page, int order)
{
- struct mem_cgroup *memcg = page->mem_cgroup;
+ struct mem_cgroup *memcg = page_memcg(page);
unsigned int nr_pages = 1 << order;
if (!memcg)
@@ -3123,7 +3114,7 @@ void __memcg_kmem_uncharge_page(struct page *page, int order)
VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page);
__memcg_kmem_uncharge(memcg, nr_pages);
- page->mem_cgroup = NULL;
+ page->memcg_data = 0;
css_put(&memcg->css);
/* slab pages do not have PageKmemcg flag set */
@@ -3274,7 +3265,7 @@ void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size)
*/
void mem_cgroup_split_huge_fixup(struct page *head)
{
- struct mem_cgroup *memcg = head->mem_cgroup;
+ struct mem_cgroup *memcg = page_memcg(head);
int i;
if (mem_cgroup_disabled())
@@ -3282,7 +3273,7 @@ void mem_cgroup_split_huge_fixup(struct page *head)
for (i = 1; i < HPAGE_PMD_NR; i++) {
css_get(&memcg->css);
- head[i].mem_cgroup = memcg;
+ head[i].memcg_data = (unsigned long)memcg;
}
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
@@ -4664,7 +4655,7 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
void mem_cgroup_track_foreign_dirty_slowpath(struct page *page,
struct bdi_writeback *wb)
{
- struct mem_cgroup *memcg = page->mem_cgroup;
+ struct mem_cgroup *memcg = page_memcg(page);
struct memcg_cgwb_frn *frn;
u64 now = get_jiffies_64();
u64 oldest_at = now;
@@ -5641,14 +5632,14 @@ static int mem_cgroup_move_account(struct page *page,
/*
* Prevent mem_cgroup_migrate() from looking at
- * page->mem_cgroup of its source page while we change it.
+ * page's memory cgroup of its source page while we change it.
*/
ret = -EBUSY;
if (!trylock_page(page))
goto out;
ret = -EINVAL;
- if (page->mem_cgroup != from)
+ if (page_memcg(page) != from)
goto out_unlock;
pgdat = page_pgdat(page);
@@ -5703,13 +5694,13 @@ static int mem_cgroup_move_account(struct page *page,
/*
* All state has been migrated, let's switch to the new memcg.
*
- * It is safe to change page->mem_cgroup here because the page
+ * It is safe to change page's memcg here because the page
* is referenced, charged, isolated, and locked: we can't race
* with (un)charging, migration, LRU putback, or anything else
- * that would rely on a stable page->mem_cgroup.
+ * that would rely on a stable page's memory cgroup.
*
* Note that lock_page_memcg is a memcg lock, not a page lock,
- * to save space. As soon as we switch page->mem_cgroup to a
+ * to save space. As soon as we switch page's memory cgroup to a
* new memcg that isn't locked, the above state can change
* concurrently again. Make sure we're truly done with it.
*/
@@ -5718,7 +5709,7 @@ static int mem_cgroup_move_account(struct page *page,
css_get(&to->css);
css_put(&from->css);
- page->mem_cgroup = to;
+ page->memcg_data = (unsigned long)to;
__unlock_page_memcg(from);
@@ -5784,7 +5775,7 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
* mem_cgroup_move_account() checks the page is valid or
* not under LRU exclusion.
*/
- if (page->mem_cgroup == mc.from) {
+ if (page_memcg(page) == mc.from) {
ret = MC_TARGET_PAGE;
if (is_device_private_page(page))
ret = MC_TARGET_DEVICE;
@@ -5828,7 +5819,7 @@ static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma,
VM_BUG_ON_PAGE(!page || !PageHead(page), page);
if (!(mc.flags & MOVE_ANON))
return ret;
- if (page->mem_cgroup == mc.from) {
+ if (page_memcg(page) == mc.from) {
ret = MC_TARGET_PAGE;
if (target) {
get_page(page);
@@ -6774,12 +6765,12 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
/*
* Every swap fault against a single page tries to charge the
* page, bail as early as possible. shmem_unuse() encounters
- * already charged pages, too. page->mem_cgroup is protected
- * by the page lock, which serializes swap cache removal, which
- * in turn serializes uncharging.
+ * already charged pages, too. page and memcg binding is
+ * protected by the page lock, which serializes swap cache
+ * removal, which in turn serializes uncharging.
*/
VM_BUG_ON_PAGE(!PageLocked(page), page);
- if (compound_head(page)->mem_cgroup)
+ if (page_memcg(compound_head(page)))
goto out;
id = lookup_swap_cgroup_id(ent);
@@ -6863,21 +6854,21 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
VM_BUG_ON_PAGE(PageLRU(page), page);
- if (!page->mem_cgroup)
+ if (!page_memcg(page))
return;
/*
* Nobody should be changing or seriously looking at
- * page->mem_cgroup at this point, we have fully
+ * page_memcg(page) at this point, we have fully
* exclusive access to the page.
*/
- if (ug->memcg != page->mem_cgroup) {
+ if (ug->memcg != page_memcg(page)) {
if (ug->memcg) {
uncharge_batch(ug);
uncharge_gather_clear(ug);
}
- ug->memcg = page->mem_cgroup;
+ ug->memcg = page_memcg(page);
/* pairs with css_put in uncharge_batch */
css_get(&ug->memcg->css);
@@ -6894,7 +6885,7 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
}
ug->dummy_page = page;
- page->mem_cgroup = NULL;
+ page->memcg_data = 0;
css_put(&ug->memcg->css);
}
@@ -6937,7 +6928,7 @@ void mem_cgroup_uncharge(struct page *page)
return;
/* Don't touch page->lru of any random page, pre-check: */
- if (!page->mem_cgroup)
+ if (!page_memcg(page))
return;
uncharge_gather_clear(&ug);
@@ -6987,11 +6978,11 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
return;
/* Page cache replacement: new page already charged? */
- if (newpage->mem_cgroup)
+ if (page_memcg(newpage))
return;
/* Swapcache readahead pages can get replaced before being charged */
- memcg = oldpage->mem_cgroup;
+ memcg = page_memcg(oldpage);
if (!memcg)
return;
@@ -7186,7 +7177,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
return;
- memcg = page->mem_cgroup;
+ memcg = page_memcg(page);
/* Readahead page, never charged */
if (!memcg)
@@ -7207,7 +7198,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
VM_BUG_ON_PAGE(oldid, page);
mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries);
- page->mem_cgroup = NULL;
+ page->memcg_data = 0;
if (!mem_cgroup_is_root(memcg))
page_counter_uncharge(&memcg->memory, nr_entries);
@@ -7250,7 +7241,7 @@ int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
return 0;
- memcg = page->mem_cgroup;
+ memcg = page_memcg(page);
/* Readahead page, never charged */
if (!memcg)
@@ -7331,7 +7322,7 @@ bool mem_cgroup_swap_full(struct page *page)
if (cgroup_memory_noswap || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
return false;
- memcg = page->mem_cgroup;
+ memcg = page_memcg(page);
if (!memcg)
return false;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 23f5066bd4a5..271133b8243b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1092,7 +1092,7 @@ static inline bool page_expected_state(struct page *page,
if (unlikely((unsigned long)page->mapping |
page_ref_count(page) |
#ifdef CONFIG_MEMCG
- (unsigned long)page->mem_cgroup |
+ (unsigned long)page_memcg(page) |
#endif
(page->flags & check_flags)))
return false;
@@ -1117,7 +1117,7 @@ static const char *page_bad_reason(struct page *page, unsigned long flags)
bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set";
}
#ifdef CONFIG_MEMCG
- if (unlikely(page->mem_cgroup))
+ if (unlikely(page_memcg(page)))
bad_reason = "page still charged to cgroup";
#endif
return bad_reason;
diff --git a/mm/page_io.c b/mm/page_io.c
index 433df1263349..9bca17ecc4df 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -291,12 +291,14 @@ static inline void count_swpout_vm_event(struct page *page)
static void bio_associate_blkg_from_page(struct bio *bio, struct page *page)
{
struct cgroup_subsys_state *css;
+ struct mem_cgroup *memcg;
- if (!page->mem_cgroup)
+ memcg = page_memcg(page);
+ if (!memcg)
return;
rcu_read_lock();
- css = cgroup_e_css(page->mem_cgroup->css.cgroup, &io_cgrp_subsys);
+ css = cgroup_e_css(memcg->css.cgroup, &io_cgrp_subsys);
bio_associate_blkg_from_css(bio, css);
rcu_read_unlock();
}
diff --git a/mm/slab.h b/mm/slab.h
index 6d7c6a5056ba..e2535cee0d33 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -242,18 +242,17 @@ static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t fla
static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
{
/*
- * page->mem_cgroup and page->obj_cgroups are sharing the same
+ * Page's memory cgroup and obj_cgroups vector are sharing the same
* space. To distinguish between them in case we don't know for sure
* that the page is a slab page (e.g. page_cgroup_ino()), let's
* always set the lowest bit of obj_cgroups.
*/
- return (struct obj_cgroup **)
- ((unsigned long)page->obj_cgroups & ~0x1UL);
+ return (struct obj_cgroup **)(page->memcg_data & ~0x1UL);
}
static inline bool page_has_obj_cgroups(struct page *page)
{
- return ((unsigned long)page->obj_cgroups & 0x1UL);
+ return page->memcg_data & 0x1UL;
}
int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
@@ -262,7 +261,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
static inline void memcg_free_page_obj_cgroups(struct page *page)
{
kfree(page_obj_cgroups(page));
- page->obj_cgroups = NULL;
+ page->memcg_data = 0;
}
static inline size_t obj_full_size(struct kmem_cache *s)
diff --git a/mm/workingset.c b/mm/workingset.c
index 975a4d2dd02e..130348cbf40a 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -257,7 +257,7 @@ void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg)
struct lruvec *lruvec;
int memcgid;
- /* Page is fully exclusive and pins page->mem_cgroup */
+ /* Page is fully exclusive and pins page's memory cgroup pointer */
VM_BUG_ON_PAGE(PageLRU(page), page);
VM_BUG_ON_PAGE(page_count(page), page);
VM_BUG_ON_PAGE(!PageLocked(page), page);
--
2.26.2
Do not use rlimit-based memory accounting for bpf local storage maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/bpf_local_storage.c | 11 -----------
1 file changed, 11 deletions(-)
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
index abd0ea385274..0875bb46e96b 100644
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -547,8 +547,6 @@ struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr)
struct bpf_local_storage_map *smap;
unsigned int i;
u32 nbuckets;
- u64 cost;
- int ret;
smap = kzalloc(sizeof(*smap), GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
if (!smap)
@@ -559,18 +557,9 @@ struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr)
/* Use at least 2 buckets, select_bucket() is undefined behavior with 1 bucket */
nbuckets = max_t(u32, 2, nbuckets);
smap->bucket_log = ilog2(nbuckets);
- cost = sizeof(*smap->buckets) * nbuckets + sizeof(*smap);
-
- ret = bpf_map_charge_init(&smap->map.memory, cost);
- if (ret < 0) {
- kfree(smap);
- return ERR_PTR(ret);
- }
-
smap->buckets = kvcalloc(sizeof(*smap->buckets), nbuckets,
GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
if (!smap->buckets) {
- bpf_map_charge_finish(&smap->map.memory);
kfree(smap);
return ERR_PTR(-ENOMEM);
}
--
2.26.2
Do not use rlimit-based memory accounting for reuseport_array maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/reuseport_array.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)
diff --git a/kernel/bpf/reuseport_array.c b/kernel/bpf/reuseport_array.c
index a55cd542f2ce..4838922f723d 100644
--- a/kernel/bpf/reuseport_array.c
+++ b/kernel/bpf/reuseport_array.c
@@ -150,9 +150,8 @@ static void reuseport_array_free(struct bpf_map *map)
static struct bpf_map *reuseport_array_alloc(union bpf_attr *attr)
{
- int err, numa_node = bpf_map_attr_numa_node(attr);
+ int numa_node = bpf_map_attr_numa_node(attr);
struct reuseport_array *array;
- struct bpf_map_memory mem;
u64 array_size;
if (!bpf_capable())
@@ -161,20 +160,13 @@ static struct bpf_map *reuseport_array_alloc(union bpf_attr *attr)
array_size = sizeof(*array);
array_size += (u64)attr->max_entries * sizeof(struct sock *);
- err = bpf_map_charge_init(&mem, array_size);
- if (err)
- return ERR_PTR(err);
-
/* allocate all map elements and zero-initialize them */
array = bpf_map_area_alloc(array_size, numa_node);
- if (!array) {
- bpf_map_charge_finish(&mem);
+ if (!array)
return ERR_PTR(-ENOMEM);
- }
/* copy mandatory map attributes */
bpf_map_init_from_attr(&array->map, attr);
- bpf_map_charge_move(&array->map.memory, &mem);
return &array->map;
}
--
2.26.2
Do not use rlimit-based memory accounting for devmap maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/devmap.c | 18 ++----------------
1 file changed, 2 insertions(+), 16 deletions(-)
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index a4dfe544946f..1fdeb7225111 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -109,8 +109,6 @@ static inline struct hlist_head *dev_map_index_hash(struct bpf_dtab *dtab,
static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
{
u32 valsize = attr->value_size;
- u64 cost = 0;
- int err;
/* check sanity of attributes. 2 value sizes supported:
* 4 bytes: ifindex
@@ -135,21 +133,13 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
if (!dtab->n_buckets) /* Overflow check */
return -EINVAL;
- cost += (u64) sizeof(struct hlist_head) * dtab->n_buckets;
- } else {
- cost += (u64) dtab->map.max_entries * sizeof(struct bpf_dtab_netdev *);
}
- /* if map size is larger than memlock limit, reject it */
- err = bpf_map_charge_init(&dtab->map.memory, cost);
- if (err)
- return -EINVAL;
-
if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
dtab->dev_index_head = dev_map_create_hash(dtab->n_buckets,
dtab->map.numa_node);
if (!dtab->dev_index_head)
- goto free_charge;
+ return -ENOMEM;
spin_lock_init(&dtab->index_lock);
} else {
@@ -157,14 +147,10 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
sizeof(struct bpf_dtab_netdev *),
dtab->map.numa_node);
if (!dtab->netdev_map)
- goto free_charge;
+ return -ENOMEM;
}
return 0;
-
-free_charge:
- bpf_map_charge_finish(&dtab->map.memory);
- return -ENOMEM;
}
static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
--
2.26.2
Do not use rlimit-based memory accounting for hashtab maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <[email protected]>
Acked-by: Song Liu <[email protected]>
---
kernel/bpf/hashtab.c | 19 +------------------
1 file changed, 1 insertion(+), 18 deletions(-)
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 2b8bbdbec872..eed12427ddd5 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -443,7 +443,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC);
struct bpf_htab *htab;
int err, i;
- u64 cost;
htab = kzalloc(sizeof(*htab), GFP_USER | __GFP_ACCOUNT);
if (!htab)
@@ -481,26 +480,12 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
htab->n_buckets > U32_MAX / sizeof(struct bucket))
goto free_htab;
- cost = (u64) htab->n_buckets * sizeof(struct bucket) +
- (u64) htab->elem_size * htab->map.max_entries;
-
- if (percpu)
- cost += (u64) round_up(htab->map.value_size, 8) *
- num_possible_cpus() * htab->map.max_entries;
- else
- cost += (u64) htab->elem_size * num_possible_cpus();
-
- /* if map size is larger than memlock limit, reject it */
- err = bpf_map_charge_init(&htab->map.memory, cost);
- if (err)
- goto free_htab;
-
err = -ENOMEM;
htab->buckets = bpf_map_area_alloc(htab->n_buckets *
sizeof(struct bucket),
htab->map.numa_node);
if (!htab->buckets)
- goto free_charge;
+ goto free_htab;
for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++) {
htab->map_locked[i] = __alloc_percpu_gfp(sizeof(int),
@@ -539,8 +524,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++)
free_percpu(htab->map_locked[i]);
bpf_map_area_free(htab->buckets);
-free_charge:
- bpf_map_charge_finish(&htab->map.memory);
free_htab:
lockdep_unregister_key(&htab->lockdep_key);
kfree(htab);
--
2.26.2
Include map metadata and the node size (struct bpf_dtab_netdev)
into the accounting.
Signed-off-by: Roman Gushchin <[email protected]>
---
kernel/bpf/devmap.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 2b5ca93c17de..a4dfe544946f 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -175,7 +175,7 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
if (!capable(CAP_NET_ADMIN))
return ERR_PTR(-EPERM);
- dtab = kzalloc(sizeof(*dtab), GFP_USER);
+ dtab = kzalloc(sizeof(*dtab), GFP_USER | __GFP_ACCOUNT);
if (!dtab)
return ERR_PTR(-ENOMEM);
@@ -602,8 +602,9 @@ static struct bpf_dtab_netdev *__dev_map_alloc_node(struct net *net,
struct bpf_prog *prog = NULL;
struct bpf_dtab_netdev *dev;
- dev = kmalloc_node(sizeof(*dev), GFP_ATOMIC | __GFP_NOWARN,
- dtab->map.numa_node);
+ dev = bpf_map_kmalloc_node(&dtab->map, sizeof(*dev),
+ GFP_ATOMIC | __GFP_NOWARN | __GFP_ACCOUNT,
+ dtab->map.numa_node);
if (!dev)
return ERR_PTR(-ENOMEM);
--
2.26.2
On 11/25/20 4:00 AM, Roman Gushchin wrote:
> In the absolute majority of cases if a process is making a kernel
> allocation, it's memory cgroup is getting charged.
>
> Bpf maps can be updated from an interrupt context and in such
> case there is no process which can be charged. It makes the memory
> accounting of bpf maps non-trivial.
>
> Fortunately, after commit 4127c6504f25 ("mm: kmem: enable kernel
> memcg accounting from interrupt contexts") and b87d8cefe43c
> ("mm, memcg: rework remote charging API to support nesting")
> it's finally possible.
>
> To do it, a pointer to the memory cgroup of the process, which created
> the map, is saved, and this cgroup can be charged for all allocations
> made from an interrupt context. This commit introduces 2 helpers:
> bpf_map_kmalloc_node() and bpf_map_alloc_percpu(). They can be used in
> the bpf code for accounted memory allocations, both in the process and
> interrupt contexts. In the interrupt context they're using the saved
> memory cgroup, otherwise the current cgroup is getting charged.
>
> Signed-off-by: Roman Gushchin <[email protected]>
Thanks for updating the cover letter; replying in this series instead
on one more item that came to mind:
[...]
> diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
> index f3fe9f53f93c..4154c616788c 100644
> --- a/kernel/bpf/syscall.c
> +++ b/kernel/bpf/syscall.c
> @@ -31,6 +31,8 @@
> #include <linux/poll.h>
> #include <linux/bpf-netns.h>
> #include <linux/rcupdate_trace.h>
> +#include <linux/memcontrol.h>
> +#include <linux/sched/mm.h>
>
> #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
> (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
> @@ -456,6 +458,77 @@ void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
> __release(&map_idr_lock);
> }
>
> +#ifdef CONFIG_MEMCG_KMEM
> +static void bpf_map_save_memcg(struct bpf_map *map)
> +{
> + map->memcg = get_mem_cgroup_from_mm(current->mm);
> +}
> +
> +static void bpf_map_release_memcg(struct bpf_map *map)
> +{
> + mem_cgroup_put(map->memcg);
> +}
> +
> +void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
> + int node)
> +{
> + struct mem_cgroup *old_memcg;
> + bool in_interrupt;
> + void *ptr;
> +
> + /*
> + * If the memory allocation is performed from an interrupt context,
> + * the memory cgroup to charge can't be determined from the context
> + * of the current task. Instead, we charge the memory cgroup, which
> + * contained the process created the map.
> + */
> + in_interrupt = in_interrupt();
> + if (in_interrupt)
> + old_memcg = set_active_memcg(map->memcg);
> +
> + ptr = kmalloc_node(size, flags, node);
> +
> + if (in_interrupt)
> + set_active_memcg(old_memcg);
> +
> + return ptr;
> +}
> +
> +void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
> + size_t align, gfp_t gfp)
> +{
> + struct mem_cgroup *old_memcg;
> + bool in_interrupt;
> + void *ptr;
> +
> + /*
> + * If the memory allocation is performed from an interrupt context,
> + * the memory cgroup to charge can't be determined from the context
> + * of the current task. Instead, we charge the memory cgroup, which
> + * contained the process created the map.
> + */
> + in_interrupt = in_interrupt();
> + if (in_interrupt)
> + old_memcg = set_active_memcg(map->memcg);
> +
> + ptr = __alloc_percpu_gfp(size, align, gfp);
> +
> + if (in_interrupt)
> + set_active_memcg(old_memcg);
For this and above bpf_map_kmalloc_node() one, wouldn't it make more sense to
perform the temporary memcg unconditionally?
old_memcg = set_active_memcg(map->memcg);
ptr = kmalloc_node(size, flags, node);
set_active_memcg(old_memcg);
I think the semantics are otherwise a bit weird and the charging unpredictable;
this way it would /always/ be accounted against the prog in the memcg that
originally created the map.
E.g. maps could be shared between progs attached to, say, XDP/tc where in_interrupt()
holds true with progs attached to skb-cgroup/egress where we're still in process
context. So some part of the memory is charged against the original map's memcg and
some other part against the current process' memcg which seems odd, no? Or, for example,
if we start to run a tracing BPF prog which updates state in a BPF map ... that tracing
prog now interferes with processes in other memcgs which may not be intentional & could
lead to potential failures there as opposed when the tracing prog is not run. My concern
is that the semantics are not quite clear and behavior unpredictable compared to always
charging against map->memcg.
Similarly, what if an orchestration prog creates dedicated memcg(s) for maps with
individual limits ... the assumed behavior (imho) would be that whatever memory is
accounted on the map it can be accurately retrieved from there & similarly limits
enforced, no? It seems that would not be the case currently.
Thoughts?
> + return ptr;
> +}
> +
> +#else
> +static void bpf_map_save_memcg(struct bpf_map *map)
> +{
> +}
> +
> +static void bpf_map_release_memcg(struct bpf_map *map)
> +{
> +}
> +#endif
> +
> /* called from workqueue */
> static void bpf_map_free_deferred(struct work_struct *work)
> {
> @@ -464,6 +537,7 @@ static void bpf_map_free_deferred(struct work_struct *work)
>
> bpf_map_charge_move(&mem, &map->memory);
> security_bpf_map_free(map);
> + bpf_map_release_memcg(map);
> /* implementation dependent freeing */
> map->ops->map_free(map);
> bpf_map_charge_finish(&mem);
> @@ -875,6 +949,8 @@ static int map_create(union bpf_attr *attr)
> if (err)
> goto free_map_sec;
>
> + bpf_map_save_memcg(map);
> +
> err = bpf_map_new_fd(map, f_flags);
> if (err < 0) {
> /* failed to allocate fd.
>
On Thu, Nov 26, 2020 at 01:21:41AM +0100, Daniel Borkmann wrote:
> On 11/25/20 4:00 AM, Roman Gushchin wrote:
> > In the absolute majority of cases if a process is making a kernel
> > allocation, it's memory cgroup is getting charged.
> >
> > Bpf maps can be updated from an interrupt context and in such
> > case there is no process which can be charged. It makes the memory
> > accounting of bpf maps non-trivial.
> >
> > Fortunately, after commit 4127c6504f25 ("mm: kmem: enable kernel
> > memcg accounting from interrupt contexts") and b87d8cefe43c
> > ("mm, memcg: rework remote charging API to support nesting")
> > it's finally possible.
> >
> > To do it, a pointer to the memory cgroup of the process, which created
> > the map, is saved, and this cgroup can be charged for all allocations
> > made from an interrupt context. This commit introduces 2 helpers:
> > bpf_map_kmalloc_node() and bpf_map_alloc_percpu(). They can be used in
> > the bpf code for accounted memory allocations, both in the process and
> > interrupt contexts. In the interrupt context they're using the saved
> > memory cgroup, otherwise the current cgroup is getting charged.
> >
> > Signed-off-by: Roman Gushchin <[email protected]>
>
> Thanks for updating the cover letter; replying in this series instead
> on one more item that came to mind:
>
> [...]
> > diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
> > index f3fe9f53f93c..4154c616788c 100644
> > --- a/kernel/bpf/syscall.c
> > +++ b/kernel/bpf/syscall.c
> > @@ -31,6 +31,8 @@
> > #include <linux/poll.h>
> > #include <linux/bpf-netns.h>
> > #include <linux/rcupdate_trace.h>
> > +#include <linux/memcontrol.h>
> > +#include <linux/sched/mm.h>
> > #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
> > (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
> > @@ -456,6 +458,77 @@ void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
> > __release(&map_idr_lock);
> > }
> > +#ifdef CONFIG_MEMCG_KMEM
> > +static void bpf_map_save_memcg(struct bpf_map *map)
> > +{
> > + map->memcg = get_mem_cgroup_from_mm(current->mm);
> > +}
> > +
> > +static void bpf_map_release_memcg(struct bpf_map *map)
> > +{
> > + mem_cgroup_put(map->memcg);
> > +}
> > +
> > +void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
> > + int node)
> > +{
> > + struct mem_cgroup *old_memcg;
> > + bool in_interrupt;
> > + void *ptr;
> > +
> > + /*
> > + * If the memory allocation is performed from an interrupt context,
> > + * the memory cgroup to charge can't be determined from the context
> > + * of the current task. Instead, we charge the memory cgroup, which
> > + * contained the process created the map.
> > + */
> > + in_interrupt = in_interrupt();
> > + if (in_interrupt)
> > + old_memcg = set_active_memcg(map->memcg);
> > +
> > + ptr = kmalloc_node(size, flags, node);
> > +
> > + if (in_interrupt)
> > + set_active_memcg(old_memcg);
> > +
> > + return ptr;
> > +}
> > +
> > +void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
> > + size_t align, gfp_t gfp)
> > +{
> > + struct mem_cgroup *old_memcg;
> > + bool in_interrupt;
> > + void *ptr;
> > +
> > + /*
> > + * If the memory allocation is performed from an interrupt context,
> > + * the memory cgroup to charge can't be determined from the context
> > + * of the current task. Instead, we charge the memory cgroup, which
> > + * contained the process created the map.
> > + */
> > + in_interrupt = in_interrupt();
> > + if (in_interrupt)
> > + old_memcg = set_active_memcg(map->memcg);
> > +
> > + ptr = __alloc_percpu_gfp(size, align, gfp);
> > +
> > + if (in_interrupt)
> > + set_active_memcg(old_memcg);
>
> For this and above bpf_map_kmalloc_node() one, wouldn't it make more sense to
> perform the temporary memcg unconditionally?
>
> old_memcg = set_active_memcg(map->memcg);
> ptr = kmalloc_node(size, flags, node);
> set_active_memcg(old_memcg);
>
> I think the semantics are otherwise a bit weird and the charging unpredictable;
> this way it would /always/ be accounted against the prog in the memcg that
> originally created the map.
>
> E.g. maps could be shared between progs attached to, say, XDP/tc where in_interrupt()
> holds true with progs attached to skb-cgroup/egress where we're still in process
> context. So some part of the memory is charged against the original map's memcg and
> some other part against the current process' memcg which seems odd, no? Or, for example,
> if we start to run a tracing BPF prog which updates state in a BPF map ... that tracing
> prog now interferes with processes in other memcgs which may not be intentional & could
> lead to potential failures there as opposed when the tracing prog is not run. My concern
> is that the semantics are not quite clear and behavior unpredictable compared to always
> charging against map->memcg.
>
> Similarly, what if an orchestration prog creates dedicated memcg(s) for maps with
> individual limits ... the assumed behavior (imho) would be that whatever memory is
> accounted on the map it can be accurately retrieved from there & similarly limits
> enforced, no? It seems that would not be the case currently.
>
> Thoughts?
I did consider this option. There are pros and cons. In general we tend to charge the cgroup
which actually allocates the memory, and I decided to stick with this rule. I agree, it's fairly
easy to come with arguments why always charging the map creator is better. The opposite is
also true: it's not clear why bpf is different here. So I'm fine with both options, if there
is a wide consensus, I'm happy to switch to the other option. In general, I believe that
the current scheme is more flexible: if someone want to pay in advance, they are free to preallocate
the map. Otherwise it's up to whoever wants to populate it.
Thanks!
Roman Gushchin <[email protected]> writes:
> On Thu, Nov 26, 2020 at 01:21:41AM +0100, Daniel Borkmann wrote:
>> On 11/25/20 4:00 AM, Roman Gushchin wrote:
>> > In the absolute majority of cases if a process is making a kernel
>> > allocation, it's memory cgroup is getting charged.
>> >
>> > Bpf maps can be updated from an interrupt context and in such
>> > case there is no process which can be charged. It makes the memory
>> > accounting of bpf maps non-trivial.
>> >
>> > Fortunately, after commit 4127c6504f25 ("mm: kmem: enable kernel
>> > memcg accounting from interrupt contexts") and b87d8cefe43c
>> > ("mm, memcg: rework remote charging API to support nesting")
>> > it's finally possible.
>> >
>> > To do it, a pointer to the memory cgroup of the process, which created
>> > the map, is saved, and this cgroup can be charged for all allocations
>> > made from an interrupt context. This commit introduces 2 helpers:
>> > bpf_map_kmalloc_node() and bpf_map_alloc_percpu(). They can be used in
>> > the bpf code for accounted memory allocations, both in the process and
>> > interrupt contexts. In the interrupt context they're using the saved
>> > memory cgroup, otherwise the current cgroup is getting charged.
>> >
>> > Signed-off-by: Roman Gushchin <[email protected]>
>>
>> Thanks for updating the cover letter; replying in this series instead
>> on one more item that came to mind:
>>
>> [...]
>> > diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
>> > index f3fe9f53f93c..4154c616788c 100644
>> > --- a/kernel/bpf/syscall.c
>> > +++ b/kernel/bpf/syscall.c
>> > @@ -31,6 +31,8 @@
>> > #include <linux/poll.h>
>> > #include <linux/bpf-netns.h>
>> > #include <linux/rcupdate_trace.h>
>> > +#include <linux/memcontrol.h>
>> > +#include <linux/sched/mm.h>
>> > #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
>> > (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
>> > @@ -456,6 +458,77 @@ void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
>> > __release(&map_idr_lock);
>> > }
>> > +#ifdef CONFIG_MEMCG_KMEM
>> > +static void bpf_map_save_memcg(struct bpf_map *map)
>> > +{
>> > + map->memcg = get_mem_cgroup_from_mm(current->mm);
>> > +}
>> > +
>> > +static void bpf_map_release_memcg(struct bpf_map *map)
>> > +{
>> > + mem_cgroup_put(map->memcg);
>> > +}
>> > +
>> > +void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
>> > + int node)
>> > +{
>> > + struct mem_cgroup *old_memcg;
>> > + bool in_interrupt;
>> > + void *ptr;
>> > +
>> > + /*
>> > + * If the memory allocation is performed from an interrupt context,
>> > + * the memory cgroup to charge can't be determined from the context
>> > + * of the current task. Instead, we charge the memory cgroup, which
>> > + * contained the process created the map.
>> > + */
>> > + in_interrupt = in_interrupt();
>> > + if (in_interrupt)
>> > + old_memcg = set_active_memcg(map->memcg);
>> > +
>> > + ptr = kmalloc_node(size, flags, node);
>> > +
>> > + if (in_interrupt)
>> > + set_active_memcg(old_memcg);
>> > +
>> > + return ptr;
>> > +}
>> > +
>> > +void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
>> > + size_t align, gfp_t gfp)
>> > +{
>> > + struct mem_cgroup *old_memcg;
>> > + bool in_interrupt;
>> > + void *ptr;
>> > +
>> > + /*
>> > + * If the memory allocation is performed from an interrupt context,
>> > + * the memory cgroup to charge can't be determined from the context
>> > + * of the current task. Instead, we charge the memory cgroup, which
>> > + * contained the process created the map.
>> > + */
>> > + in_interrupt = in_interrupt();
>> > + if (in_interrupt)
>> > + old_memcg = set_active_memcg(map->memcg);
>> > +
>> > + ptr = __alloc_percpu_gfp(size, align, gfp);
>> > +
>> > + if (in_interrupt)
>> > + set_active_memcg(old_memcg);
>>
>> For this and above bpf_map_kmalloc_node() one, wouldn't it make more sense to
>> perform the temporary memcg unconditionally?
>>
>> old_memcg = set_active_memcg(map->memcg);
>> ptr = kmalloc_node(size, flags, node);
>> set_active_memcg(old_memcg);
>>
>> I think the semantics are otherwise a bit weird and the charging unpredictable;
>> this way it would /always/ be accounted against the prog in the memcg that
>> originally created the map.
>>
>> E.g. maps could be shared between progs attached to, say, XDP/tc where in_interrupt()
>> holds true with progs attached to skb-cgroup/egress where we're still in process
>> context. So some part of the memory is charged against the original map's memcg and
>> some other part against the current process' memcg which seems odd, no? Or, for example,
>> if we start to run a tracing BPF prog which updates state in a BPF map ... that tracing
>> prog now interferes with processes in other memcgs which may not be intentional & could
>> lead to potential failures there as opposed when the tracing prog is not run. My concern
>> is that the semantics are not quite clear and behavior unpredictable compared to always
>> charging against map->memcg.
>>
>> Similarly, what if an orchestration prog creates dedicated memcg(s) for maps with
>> individual limits ... the assumed behavior (imho) would be that whatever memory is
>> accounted on the map it can be accurately retrieved from there & similarly limits
>> enforced, no? It seems that would not be the case currently.
>>
>> Thoughts?
>
> I did consider this option. There are pros and cons. In general we
> tend to charge the cgroup which actually allocates the memory, and I
> decided to stick with this rule. I agree, it's fairly easy to come
> with arguments why always charging the map creator is better. The
> opposite is also true: it's not clear why bpf is different here. So
> I'm fine with both options, if there is a wide consensus, I'm happy to
> switch to the other option. In general, I believe that the current
> scheme is more flexible: if someone want to pay in advance, they are
> free to preallocate the map. Otherwise it's up to whoever wants to
> populate it.
I think I agree with Daniel here: conceptually the memory used by a map
ought to belong to that map's memcg. I can see how the other scheme can
be more flexible, but as Daniel points out it seems like it can lead to
hard-to-debug errors...
(Side note: I'm really excited about this work in general! The ulimit
thing has been a major pain...)
-Toke
On Wed, Nov 25, 2020 at 6:30 PM Roman Gushchin <[email protected]> wrote:
>
> I did consider this option. There are pros and cons. In general we tend to charge the cgroup
> which actually allocates the memory, and I decided to stick with this rule. I agree, it's fairly
> easy to come with arguments why always charging the map creator is better. The opposite is
> also true: it's not clear why bpf is different here. So I'm fine with both options, if there
> is a wide consensus, I'm happy to switch to the other option. In general, I believe that
> the current scheme is more flexible.
I don't understand the 'more flexible' part.
The current_memcg or map_memcg approach makes it less predictable.
pre-alloc vs not is somewhat orthogonal.
I've grepped through the kernel where set_active_memcg() is used
and couldn't find a conditional pattern of its usage.
If memcg is known it's used. I couldn't come up with the use case where
using current memcg is the more correct thing to do.
> In general we tend to charge the cgroup which actually allocates the memory
that makes sense where allocation is driven by the user process.
Like user space doing a syscall then all kernel allocation would be
from memcg of that process.
But bpf tracing allocations are not something that the user process requested
the kernel to do. It's like another user space process tapped into another.
Arguably when bpf prog is running the two user processes are active.
One that created the map and loaded the prog and another that is being traced.
I think there will be cases where bpf prog will request the kernel to allocate
memory on behalf of the process being traced, but that memory should be
given back to the process and accessible by it in some form.
Like bpf prog could ask the kernel to grow heap of that process or
trigger readahead.
In such case current_memcg would be the right thing to charge.
On Thu, Nov 26, 2020 at 10:56:12AM +0100, Toke H?iland-J?rgensen wrote:
> Roman Gushchin <[email protected]> writes:
>
> > On Thu, Nov 26, 2020 at 01:21:41AM +0100, Daniel Borkmann wrote:
> >> On 11/25/20 4:00 AM, Roman Gushchin wrote:
> >> > In the absolute majority of cases if a process is making a kernel
> >> > allocation, it's memory cgroup is getting charged.
> >> >
> >> > Bpf maps can be updated from an interrupt context and in such
> >> > case there is no process which can be charged. It makes the memory
> >> > accounting of bpf maps non-trivial.
> >> >
> >> > Fortunately, after commit 4127c6504f25 ("mm: kmem: enable kernel
> >> > memcg accounting from interrupt contexts") and b87d8cefe43c
> >> > ("mm, memcg: rework remote charging API to support nesting")
> >> > it's finally possible.
> >> >
> >> > To do it, a pointer to the memory cgroup of the process, which created
> >> > the map, is saved, and this cgroup can be charged for all allocations
> >> > made from an interrupt context. This commit introduces 2 helpers:
> >> > bpf_map_kmalloc_node() and bpf_map_alloc_percpu(). They can be used in
> >> > the bpf code for accounted memory allocations, both in the process and
> >> > interrupt contexts. In the interrupt context they're using the saved
> >> > memory cgroup, otherwise the current cgroup is getting charged.
> >> >
> >> > Signed-off-by: Roman Gushchin <[email protected]>
> >>
> >> Thanks for updating the cover letter; replying in this series instead
> >> on one more item that came to mind:
> >>
> >> [...]
> >> > diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
> >> > index f3fe9f53f93c..4154c616788c 100644
> >> > --- a/kernel/bpf/syscall.c
> >> > +++ b/kernel/bpf/syscall.c
> >> > @@ -31,6 +31,8 @@
> >> > #include <linux/poll.h>
> >> > #include <linux/bpf-netns.h>
> >> > #include <linux/rcupdate_trace.h>
> >> > +#include <linux/memcontrol.h>
> >> > +#include <linux/sched/mm.h>
> >> > #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
> >> > (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
> >> > @@ -456,6 +458,77 @@ void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
> >> > __release(&map_idr_lock);
> >> > }
> >> > +#ifdef CONFIG_MEMCG_KMEM
> >> > +static void bpf_map_save_memcg(struct bpf_map *map)
> >> > +{
> >> > + map->memcg = get_mem_cgroup_from_mm(current->mm);
> >> > +}
> >> > +
> >> > +static void bpf_map_release_memcg(struct bpf_map *map)
> >> > +{
> >> > + mem_cgroup_put(map->memcg);
> >> > +}
> >> > +
> >> > +void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
> >> > + int node)
> >> > +{
> >> > + struct mem_cgroup *old_memcg;
> >> > + bool in_interrupt;
> >> > + void *ptr;
> >> > +
> >> > + /*
> >> > + * If the memory allocation is performed from an interrupt context,
> >> > + * the memory cgroup to charge can't be determined from the context
> >> > + * of the current task. Instead, we charge the memory cgroup, which
> >> > + * contained the process created the map.
> >> > + */
> >> > + in_interrupt = in_interrupt();
> >> > + if (in_interrupt)
> >> > + old_memcg = set_active_memcg(map->memcg);
> >> > +
> >> > + ptr = kmalloc_node(size, flags, node);
> >> > +
> >> > + if (in_interrupt)
> >> > + set_active_memcg(old_memcg);
> >> > +
> >> > + return ptr;
> >> > +}
> >> > +
> >> > +void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
> >> > + size_t align, gfp_t gfp)
> >> > +{
> >> > + struct mem_cgroup *old_memcg;
> >> > + bool in_interrupt;
> >> > + void *ptr;
> >> > +
> >> > + /*
> >> > + * If the memory allocation is performed from an interrupt context,
> >> > + * the memory cgroup to charge can't be determined from the context
> >> > + * of the current task. Instead, we charge the memory cgroup, which
> >> > + * contained the process created the map.
> >> > + */
> >> > + in_interrupt = in_interrupt();
> >> > + if (in_interrupt)
> >> > + old_memcg = set_active_memcg(map->memcg);
> >> > +
> >> > + ptr = __alloc_percpu_gfp(size, align, gfp);
> >> > +
> >> > + if (in_interrupt)
> >> > + set_active_memcg(old_memcg);
> >>
> >> For this and above bpf_map_kmalloc_node() one, wouldn't it make more sense to
> >> perform the temporary memcg unconditionally?
> >>
> >> old_memcg = set_active_memcg(map->memcg);
> >> ptr = kmalloc_node(size, flags, node);
> >> set_active_memcg(old_memcg);
> >>
> >> I think the semantics are otherwise a bit weird and the charging unpredictable;
> >> this way it would /always/ be accounted against the prog in the memcg that
> >> originally created the map.
> >>
> >> E.g. maps could be shared between progs attached to, say, XDP/tc where in_interrupt()
> >> holds true with progs attached to skb-cgroup/egress where we're still in process
> >> context. So some part of the memory is charged against the original map's memcg and
> >> some other part against the current process' memcg which seems odd, no? Or, for example,
> >> if we start to run a tracing BPF prog which updates state in a BPF map ... that tracing
> >> prog now interferes with processes in other memcgs which may not be intentional & could
> >> lead to potential failures there as opposed when the tracing prog is not run. My concern
> >> is that the semantics are not quite clear and behavior unpredictable compared to always
> >> charging against map->memcg.
> >>
> >> Similarly, what if an orchestration prog creates dedicated memcg(s) for maps with
> >> individual limits ... the assumed behavior (imho) would be that whatever memory is
> >> accounted on the map it can be accurately retrieved from there & similarly limits
> >> enforced, no? It seems that would not be the case currently.
> >>
> >> Thoughts?
> >
> > I did consider this option. There are pros and cons. In general we
> > tend to charge the cgroup which actually allocates the memory, and I
> > decided to stick with this rule. I agree, it's fairly easy to come
> > with arguments why always charging the map creator is better. The
> > opposite is also true: it's not clear why bpf is different here. So
> > I'm fine with both options, if there is a wide consensus, I'm happy to
> > switch to the other option. In general, I believe that the current
> > scheme is more flexible: if someone want to pay in advance, they are
> > free to preallocate the map. Otherwise it's up to whoever wants to
> > populate it.
>
> I think I agree with Daniel here: conceptually the memory used by a map
> ought to belong to that map's memcg. I can see how the other scheme can
> be more flexible, but as Daniel points out it seems like it can lead to
> hard-to-debug errors...
Ok, I'll switch to always charging the map's memcg in the next version.
>
> (Side note: I'm really excited about this work in general! The ulimit
> thing has been a major pain...)
Great! Thanks!