linux-brain/include
Johannes Weiner 41c7f46c89 mm: memcontrol: fix occasional OOMs due to proportional memory.low reclaim
[ Upstream commit f56ce412a59d7d938b81de8878faef128812482c ]

We've noticed occasional OOM killing when memory.low settings are in
effect for cgroups.  This is unexpected and undesirable as memory.low is
supposed to express non-OOMing memory priorities between cgroups.

The reason for this is proportional memory.low reclaim.  When cgroups
are below their memory.low threshold, reclaim passes them over in the
first round, and then retries if it couldn't find pages anywhere else.
But when cgroups are slightly above their memory.low setting, page scan
force is scaled down and diminished in proportion to the overage, to the
point where it can cause reclaim to fail as well - only in that case we
currently don't retry, and instead trigger OOM.

To fix this, hook proportional reclaim into the same retry logic we have
in place for when cgroups are skipped entirely.  This way if reclaim
fails and some cgroups were scanned with diminished pressure, we'll try
another full-force cycle before giving up and OOMing.

[akpm@linux-foundation.org: coding-style fixes]

Link: https://lkml.kernel.org/r/20210817180506.220056-1-hannes@cmpxchg.org
Fixes: 9783aa9917 ("mm, memcg: proportional memory.{low,min} reclaim")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Leon Yang <lnyng@fb.com>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Chris Down <chris@chrisdown.name>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: <stable@vger.kernel.org>		[5.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-08-26 08:36:22 -04:00
..
acpi ACPI: fix NULL pointer dereference 2021-08-08 09:04:08 +02:00
asm-generic vmlinux.lds.h: Handle clang's module.{c,d}tor sections 2021-08-18 08:57:04 +02:00
clocksource
crypto crypto: shash - avoid comparing pointers to exported functions under CFI 2021-07-14 16:53:13 +02:00
drm drm: Return -ENOTTY for non-drm ioctls 2021-07-28 13:31:01 +02:00
dt-bindings clk: imx8mn: Fix incorrect clock defines 2020-03-18 07:17:55 +01:00
keys certs: Add EFI_CERT_X509_GUID support for dbx entries 2021-06-30 08:47:55 -04:00
kvm
linux mm: memcontrol: fix occasional OOMs due to proportional memory.low reclaim 2021-08-26 08:36:22 -04:00
math-emu
media media: subdev: disallow ioctl for saa6588/davinci 2021-07-19 08:53:17 +02:00
misc
net psample: Add a fwd declaration for skbuff 2021-08-18 08:56:59 +02:00
pcmcia
ras
rdma RDMA/umem: Fix signature of stub ib_umem_find_best_pgsz() 2020-10-29 09:57:47 +01:00
scsi scsi: iscsi: Fix conn use after free during resets 2021-07-20 16:10:43 +02:00
soc irqchip/eznps: Fix build error for !ARC700 builds 2020-09-17 13:47:47 +02:00
sound ALSA: hda: intel-nhlt: verify config type 2021-03-09 11:09:39 +01:00
target scsi: target: core: Add cmd length set before cmd complete 2021-03-17 17:03:45 +01:00
trace afs: Fix tracepoint string placement with built-in AFS 2021-07-28 13:30:58 +02:00
uapi net: fix mistake path for netdev_features_strings 2021-07-19 08:53:11 +02:00
vdso
video
xen Xen/gntdev: correct error checking in gntdev_map_grant_pages() 2021-02-23 15:02:26 +01:00