From aeed1d325d429ac9699c4bf62d17156d60905519 Mon Sep 17 00:00:00 2001 From: Vladimir Davydov <vdavydov.dev@gmail.com> Date: Fri, 17 Aug 2018 15:48:17 -0700 Subject: [PATCH] mm/vmscan.c: generalize shrink_slab() calls in shrink_node() The patch makes shrink_slab() be called for root_mem_cgroup in the same way as it's called for the rest of cgroups. This simplifies the logic and improves the readability. [ktkhai@virtuozzo.com: wrote changelog] Link: http://lkml.kernel.org/r/153063068338.1818.11496084754797453962.stgit@localhost.localdomain Signed-off-by: Vladimir Davydov <vdavydov.dev@gmail.com> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Tested-by: Shakeel Butt <shakeelb@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Josef Bacik <jbacik@fb.com> Cc: Li RongQing <lirongqing@baidu.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matthias Kaehlcke <mka@chromium.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Roman Gushchin <guro@fb.com> Cc: Sahitya Tummala <stummala@codeaurora.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- mm/vmscan.c | 21 ++++++--------------- 1 file changed, 6 insertions(+), 15 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index d7a5b8566869..2aa3cb760189 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -627,10 +627,8 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid, * @nid is passed along to shrinkers with SHRINKER_NUMA_AWARE set, * unaware shrinkers will receive a node id of 0 instead. * - * @memcg specifies the memory cgroup to target. If it is not NULL, - * only shrinkers with SHRINKER_MEMCG_AWARE set will be called to scan - * objects from the memory cgroup specified. Otherwise, only unaware - * shrinkers are called. + * @memcg specifies the memory cgroup to target. Unaware shrinkers + * are called only if it is the root cgroup. * * @priority is sc->priority, we take the number of objects and >> by priority * in order to get the scan target. @@ -644,7 +642,7 @@ static unsigned long shrink_slab(gfp_t gfp_mask, int nid, struct shrinker *shrinker; unsigned long freed = 0; - if (memcg && !mem_cgroup_is_root(memcg)) + if (!mem_cgroup_is_root(memcg)) return shrink_slab_memcg(gfp_mask, nid, memcg, priority); if (!down_read_trylock(&shrinker_rwsem)) @@ -657,9 +655,6 @@ static unsigned long shrink_slab(gfp_t gfp_mask, int nid, .memcg = memcg, }; - if (!!memcg != !!(shrinker->flags & SHRINKER_MEMCG_AWARE)) - continue; - if (!(shrinker->flags & SHRINKER_NUMA_AWARE)) sc.nid = 0; @@ -689,6 +684,7 @@ void drop_slab_node(int nid) struct mem_cgroup *memcg = NULL; freed = 0; + memcg = mem_cgroup_iter(NULL, NULL, NULL); do { freed += shrink_slab(GFP_KERNEL, nid, memcg, 0); } while ((memcg = mem_cgroup_iter(NULL, memcg, NULL)) != NULL); @@ -2708,9 +2704,8 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc) shrink_node_memcg(pgdat, memcg, sc, &lru_pages); node_lru_pages += lru_pages; - if (memcg) - shrink_slab(sc->gfp_mask, pgdat->node_id, - memcg, sc->priority); + shrink_slab(sc->gfp_mask, pgdat->node_id, + memcg, sc->priority); /* Record the group's reclaim efficiency */ vmpressure(sc->gfp_mask, memcg, false, @@ -2734,10 +2729,6 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc) } } while ((memcg = mem_cgroup_iter(root, memcg, &reclaim))); - if (global_reclaim(sc)) - shrink_slab(sc->gfp_mask, pgdat->node_id, NULL, - sc->priority); - if (reclaim_state) { sc->nr_reclaimed += reclaim_state->reclaimed_slab; reclaim_state->reclaimed_slab = 0; -- GitLab