High memory limit is currently recorded directly in struct mem_cgroup. We are about to add a high limit for swap, move the field to struct page_counter and add some helpers. Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Reviewed-by: Shakeel Butt <shakeelb@xxxxxxxxxx> -- v5: make page_counter_set_high() a static inline in the header v4: new patch --- include/linux/memcontrol.h | 3 --- include/linux/page_counter.h | 13 +++++++++++++ mm/memcontrol.c | 17 +++++++++-------- 3 files changed, 22 insertions(+), 11 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index e0bcef180672..d726867d8af9 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -206,9 +206,6 @@ struct mem_cgroup { struct page_counter kmem; struct page_counter tcpmem; - /* Upper bound of normal memory consumption range */ - unsigned long high; - /* Range enforcement for interrupt charges */ struct work_struct high_work; diff --git a/include/linux/page_counter.h b/include/linux/page_counter.h index bab7e57f659b..6a89ff948412 100644 --- a/include/linux/page_counter.h +++ b/include/linux/page_counter.h @@ -10,6 +10,7 @@ struct page_counter { atomic_long_t usage; unsigned long min; unsigned long low; + unsigned long high; unsigned long max; struct page_counter *parent; @@ -55,6 +56,13 @@ bool page_counter_try_charge(struct page_counter *counter, void page_counter_uncharge(struct page_counter *counter, unsigned long nr_pages); void page_counter_set_min(struct page_counter *counter, unsigned long nr_pages); void page_counter_set_low(struct page_counter *counter, unsigned long nr_pages); + +static inline void page_counter_set_high(struct page_counter *counter, + unsigned long nr_pages) +{ + WRITE_ONCE(counter->high, nr_pages); +} + int page_counter_set_max(struct page_counter *counter, unsigned long nr_pages); int page_counter_memparse(const char *buf, const char *max, unsigned long *nr_pages); @@ -64,4 +72,9 @@ static inline void page_counter_reset_watermark(struct page_counter *counter) counter->watermark = page_counter_read(counter); } +static inline bool page_counter_is_above_high(struct page_counter *counter) +{ + return page_counter_read(counter) > READ_ONCE(counter->high); +} + #endif /* _LINUX_PAGE_COUNTER_H */ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index dd8605a9137a..d4b7bc80aa38 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2233,7 +2233,7 @@ static void reclaim_high(struct mem_cgroup *memcg, gfp_t gfp_mask) { do { - if (page_counter_read(&memcg->memory) <= READ_ONCE(memcg->high)) + if (!page_counter_is_above_high(&memcg->memory)) continue; memcg_memory_event(memcg, MEMCG_HIGH); try_to_free_mem_cgroup_pages(memcg, nr_pages, gfp_mask, true); @@ -2326,7 +2326,7 @@ static u64 mem_find_max_overage(struct mem_cgroup *memcg) do { overage = calculate_overage(page_counter_read(&memcg->memory), - READ_ONCE(memcg->high)); + READ_ONCE(memcg->memory.high)); max_overage = max(overage, max_overage); } while ((memcg = parent_mem_cgroup(memcg)) && !mem_cgroup_is_root(memcg)); @@ -2585,7 +2585,7 @@ static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, * reclaim, the cost of mismatch is negligible. */ do { - if (page_counter_read(&memcg->memory) > READ_ONCE(memcg->high)) { + if (page_counter_is_above_high(&memcg->memory)) { /* Don't bother a random interrupted task */ if (in_interrupt()) { schedule_work(&memcg->high_work); @@ -4286,7 +4286,7 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, while ((parent = parent_mem_cgroup(memcg))) { unsigned long ceiling = min(READ_ONCE(memcg->memory.max), - READ_ONCE(memcg->high)); + READ_ONCE(memcg->memory.high)); unsigned long used = page_counter_read(&memcg->memory); *pheadroom = min(*pheadroom, ceiling - min(ceiling, used)); @@ -5011,7 +5011,7 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) if (IS_ERR(memcg)) return ERR_CAST(memcg); - WRITE_ONCE(memcg->high, PAGE_COUNTER_MAX); + page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); memcg->soft_limit = PAGE_COUNTER_MAX; if (parent) { memcg->swappiness = mem_cgroup_swappiness(parent); @@ -5164,7 +5164,7 @@ static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) page_counter_set_max(&memcg->tcpmem, PAGE_COUNTER_MAX); page_counter_set_min(&memcg->memory, 0); page_counter_set_low(&memcg->memory, 0); - WRITE_ONCE(memcg->high, PAGE_COUNTER_MAX); + page_counter_set_high(&memcg->memory, PAGE_COUNTER_MAX); memcg->soft_limit = PAGE_COUNTER_MAX; memcg_wb_domain_size_changed(memcg); } @@ -5984,7 +5984,8 @@ static ssize_t memory_low_write(struct kernfs_open_file *of, static int memory_high_show(struct seq_file *m, void *v) { - return seq_puts_memcg_tunable(m, READ_ONCE(mem_cgroup_from_seq(m)->high)); + return seq_puts_memcg_tunable(m, + READ_ONCE(mem_cgroup_from_seq(m)->memory.high)); } static ssize_t memory_high_write(struct kernfs_open_file *of, @@ -6001,7 +6002,7 @@ static ssize_t memory_high_write(struct kernfs_open_file *of, if (err) return err; - WRITE_ONCE(memcg->high, high); + page_counter_set_high(&memcg->memory, high); for (;;) { unsigned long nr_pages = page_counter_read(&memcg->memory); -- 2.25.4