Commit 68ae564b authored by David Rientjes's avatar David Rientjes Committed by Linus Torvalds
Browse files

mm, memcg: avoid unnecessary function call when memcg is disabled

While profiling numa/core v16 with cgroup_disable=memory on the command
line, I noticed mem_cgroup_count_vm_event() still showed up as high as
0.60% in perftop.

This occurs because the function is called extremely often even when memcg
is disabled.

To fix this, inline the check for mem_cgroup_disabled() so we avoid the
unnecessary function call if memcg is disabled.
Signed-off-by: default avatarDavid Rientjes <>
Acked-by: default avatarKAMEZAWA Hiroyuki <>
Acked-by: default avatarGlauber Costa <>
Acked-by: default avatarMichal Hocko <>
Acked-by: default avatarJohannes Weiner <>
Signed-off-by: default avatarAndrew Morton <>
Signed-off-by: default avatarLinus Torvalds <>
parent 05b0afd7
......@@ -181,7 +181,14 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
gfp_t gfp_mask,
unsigned long *total_scanned);
void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx);
void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx);
static inline void mem_cgroup_count_vm_event(struct mm_struct *mm,
enum vm_event_item idx)
if (mem_cgroup_disabled())
__mem_cgroup_count_vm_event(mm, idx);
void mem_cgroup_split_huge_fixup(struct page *head);
......@@ -59,6 +59,8 @@
#include <trace/events/vmscan.h>
struct cgroup_subsys mem_cgroup_subsys __read_mostly;
static struct mem_cgroup *root_mem_cgroup __read_mostly;
......@@ -1015,7 +1017,7 @@ void mem_cgroup_iter_break(struct mem_cgroup *root,
iter != NULL; \
iter = mem_cgroup_iter(NULL, iter, NULL))
void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
struct mem_cgroup *memcg;
......@@ -1040,7 +1042,7 @@ void mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
* mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg
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