diff options
| author | Roman Gushchin <roman.gushchin@linux.dev> | 2024-07-26 20:31:08 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-09-01 20:25:50 -0700 |
| commit | f77bd4b14ccfd38dfcfe67eecad517b8ec1b7f37 (patch) | |
| tree | 4f3cac611c360d63670c008977489ec4244e9669 /include/linux/page_counter.h | |
| parent | 6c469957cd172c1bcea8c5b77bc711a245b0934f (diff) | |
mm: memcg: don't call propagate_protected_usage() needlessly
Patch series "mm: memcg: page counters optimizations", v3.
This patchset contains 3 independent small optimizations of page counters.
This patch (of 3):
Memory protection (min/low) requires a constant tracking of protected
memory usage. propagate_protected_usage() is called on each page counters
update and does a number of operations even in cases when the actual
memory protection functionality is not supported (e.g. hugetlb cgroups or
memcg swap counters).
It's obviously inefficient and leads to a waste of CPU cycles. It can be
addressed by calling propagate_protected_usage() only for the counters
which do support memory guarantees. As of now it's only memcg->memory -
the unified memory memcg counter.
Link: https://lkml.kernel.org/r/20240726203110.1577216-2-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux/page_counter.h')
| -rw-r--r-- | include/linux/page_counter.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/include/linux/page_counter.h b/include/linux/page_counter.h index 904c52f97284..0b8e993f9163 100644 --- a/include/linux/page_counter.h +++ b/include/linux/page_counter.h @@ -31,6 +31,7 @@ struct page_counter { /* Keep all the read most fields in a separete cacheline. */ CACHELINE_PADDING(_pad2_); + bool protection_support; unsigned long min; unsigned long low; unsigned long high; @@ -44,12 +45,17 @@ struct page_counter { #define PAGE_COUNTER_MAX (LONG_MAX / PAGE_SIZE) #endif +/* + * Protection is supported only for the first counter (with id 0). + */ static inline void page_counter_init(struct page_counter *counter, - struct page_counter *parent) + struct page_counter *parent, + bool protection_support) { atomic_long_set(&counter->usage, 0); counter->max = PAGE_COUNTER_MAX; counter->parent = parent; + counter->protection_support = protection_support; } static inline unsigned long page_counter_read(struct page_counter *counter) |