xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mm: clean up and clarify lruvec lookup procedure

Browse Source 
There is a per-memcg lruvec and a NUMA node lruvec.  Which one is being
used is somewhat confusing right now, and it's easy to make mistakes -
especially when it comes to global reclaim.

How it works: when memory cgroups are enabled, we always use the
root_mem_cgroup's per-node lruvecs.  When memory cgroups are not compiled
in or disabled at runtime, we use pgdat->lruvec.

Document that in a comment.

Due to the way the reclaim code is generalized, all lookups use the
mem_cgroup_lruvec() helper function, and nobody should have to find the
right lruvec manually right now.  But to avoid future mistakes, rename the
pgdat->lruvec member to pgdat->__lruvec and delete the convenience wrapper
that suggests it's a commonly accessed member.

While in this area, swap the mem_cgroup_lruvec() argument order.  The name
suggests a memcg operation, yet it takes a pgdat first and a memcg second.
I have to double take every time I call this.  Fix that.

Link: http://lkml.kernel.org/r/20191022144803.302233-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Johannes Weiner
2019-11-30 17:55:34 -08:00
committed by Linus Torvalds
parent de3b01506e
commit 867e5e1de1
7 changed files with 35 additions and 34 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
mm/workingset.c
View File

@@ -233,7 +233,7 @@ void *workingset_eviction(struct page *page)
VM_BUG_ON_PAGE(page_count(page), page);
VM_BUG_ON_PAGE(!PageLocked(page), page);
lruvec = mem_cgroup_lruvec(pgdat, memcg);
lruvec = mem_cgroup_lruvec(memcg, pgdat);
eviction = atomic_long_inc_return(&lruvec->inactive_age);
return pack_shadow(memcgid, pgdat, eviction, PageWorkingset(page));
}
@@ -280,7 +280,7 @@ void workingset_refault(struct page *page, void *shadow)
memcg = mem_cgroup_from_id(memcgid);
if (!mem_cgroup_disabled() && !memcg)
goto out;
lruvec = mem_cgroup_lruvec(pgdat, memcg);
lruvec = mem_cgroup_lruvec(memcg, pgdat);
refault = atomic_long_read(&lruvec->inactive_age);
active_file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE, MAX_NR_ZONES);
@@ -345,7 +345,7 @@ void workingset_activation(struct page *page)
memcg = page_memcg_rcu(page);
if (!mem_cgroup_disabled() && !memcg)
goto out;
lruvec = mem_cgroup_lruvec(page_pgdat(page), memcg);
lruvec = mem_cgroup_lruvec(memcg, page_pgdat(page));
atomic_long_inc(&lruvec->inactive_age);
out:
rcu_read_unlock();
@@ -426,7 +426,7 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
struct lruvec *lruvec;
int i;
lruvec = mem_cgroup_lruvec(NODE_DATA(sc->nid), sc->memcg);
lruvec = mem_cgroup_lruvec(sc->memcg, NODE_DATA(sc->nid));
for (pages = 0, i = 0; i < NR_LRU_LISTS; i++)
pages += lruvec_page_state_local(lruvec,
NR_LRU_BASE + i);