diff options
Diffstat (limited to 'include/linux/page_counter.h')
| -rw-r--r-- | include/linux/page_counter.h | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/include/linux/page_counter.h b/include/linux/page_counter.h index 679591301994..c141ea9a95ef 100644 --- a/include/linux/page_counter.h +++ b/include/linux/page_counter.h @@ -3,15 +3,17 @@ #define _LINUX_PAGE_COUNTER_H #include <linux/atomic.h> +#include <linux/cache.h> #include <linux/kernel.h> #include <asm/page.h> struct page_counter { + /* + * Make sure 'usage' does not share cacheline with any other field. The + * memcg->memory.usage is a hot member of struct mem_cgroup. + */ atomic_long_t usage; - unsigned long min; - unsigned long low; - unsigned long high; - unsigned long max; + CACHELINE_PADDING(_pad1_); /* effective memory.min and memory.min usage tracking */ unsigned long emin; @@ -23,18 +25,18 @@ struct page_counter { atomic_long_t low_usage; atomic_long_t children_low_usage; - /* legacy */ unsigned long watermark; unsigned long failcnt; - /* - * 'parent' is placed here to be far from 'usage' to reduce - * cache false sharing, as 'usage' is written mostly while - * parent is frequently read for cgroup's hierarchical - * counting nature. - */ + /* Keep all the read most fields in a separete cacheline. */ + CACHELINE_PADDING(_pad2_); + + unsigned long min; + unsigned long low; + unsigned long high; + unsigned long max; struct page_counter *parent; -}; +} ____cacheline_internodealigned_in_smp; #if BITS_PER_LONG == 32 #define PAGE_COUNTER_MAX LONG_MAX |