On Sat, Aug 08, 2020 at 09:22:29PM +0800, Alex Shi wrote: > > > 在 2020/8/5 下午9:02, Alex Shi 写道: > > > > > > 在 2020/8/5 下午8:28, Alex Shi 写道: > >> The last patch has a problem on define. this version could fix it. > >> > >> BTW, I see some !memcg happens when MEMCG compilered but disabled by > >> cgroup_disable > >> > >> > >> [ 94.657666] ---[ end trace f1f34bfc3b32ed2f ]--- > >> [ 95.138995] anon flags: > >> 0x5005b48008000d(locked|uptodate|dirty|swapbacked) > >> [ 95.146220] raw: 005005b48008000d dead000000000100 dead000000000122 > >> ffff8897c7c76ad1 > >> [ 95.154549] raw: 0000000000000022 0000000000000000 0000000200000000 > >> 0000000000000000 > >> [ 95.162876] page dumped because: VM_WARN_ON_ONCE_PAGE(!memcg) > >> > >> > > > > The following patch may helpful. > > Any comments for the 2 patches? > > Thanks > Alex > > > > > From 8bfb26a2e37e08dc61d20212bcfa5812a367ba94 Mon Sep 17 00:00:00 2001 > > From: Alex Shi <[email protected]> > > Date: Wed, 5 Aug 2020 20:32:12 +0800 > > Subject: [PATCH] mm/memcg: don't try charge swap if memcg disabled > > > > If we disabled memcg by cgroup_disable=memory, the swap charges are > > still called. Let's return from the funcs earlier and keep WARN_ON > > monitor. > > > > Signed-off-by: Alex Shi <[email protected]> > > Cc: Johannes Weiner <[email protected]> > > Cc: Michal Hocko <[email protected]> > > Cc: Vladimir Davydov <[email protected]> > > Cc: Andrew Morton <[email protected]> > > Cc: [email protected] > > Cc: [email protected] > > Cc: [email protected] > > --- > > mm/memcontrol.c | 6 ++++++ > > 1 file changed, 6 insertions(+) > > > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > > index cb07a48d53aa..65f2b42d25af 100644 > > --- a/mm/memcontrol.c > > +++ b/mm/memcontrol.c > > @@ -7163,6 +7163,9 @@ void mem_cgroup_swapout(struct page *page, > > swp_entry_t entry) > > VM_BUG_ON_PAGE(PageLRU(page), page); > > VM_BUG_ON_PAGE(page_count(page), page); > > > > + if (mem_cgroup_disabled()) > > + return; > > + > > if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) > > return; > > > > @@ -7228,6 +7231,9 @@ int mem_cgroup_try_charge_swap(struct page *page, > > swp_entry_t entry) > > struct mem_cgroup *memcg; > > unsigned short oldid; > > > > + if (mem_cgroup_disabled()) > > + return 0; > > + > > if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) > > return 0; > > > >
Hi Alex, this patch looks good to me. Please, feel free to add Reviewed-by: Roman Gushchin <[email protected]> What's the second patch? Thanks!
