On Fri, Oct 26, 2018 at 07:18:59AM -0400, Sasha Levin wrote:

This reverts commit 62aad93f09c1952ede86405894df1b22012fd5ab.

Which was upstream commit 172b06c32b94 ("mm: slowly shrink slabs with a relatively small number of objects").

The upstream commit was found to cause regressions. While there is a proposed fix upstream, revent this patch from stable trees for now as testing the fix will take some time.

Signed-off-by: Sasha Levin sashal@kernel.org

mm/vmscan.c | 11 ----------- 1 file changed, 11 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c index fc0436407471..03822f86f288 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -386,17 +386,6 @@ static unsigned long do_shrink_slab(struct shrink_control *shrinkctl, delta = freeable >> priority; delta *= 4; do_div(delta, shrinker->seeks);

• /*

• * Make sure we apply some minimal pressure on default priority
  

• * even on small cgroups. Stale objects are not only consuming memory
  

• * by themselves, but can also hold a reference to a dying cgroup,
  

• * preventing it from being reclaimed. A dying cgroup with all
  

• * corresponding structures like per-cpu stats and kmem caches
  

• * can be really big, so it may lead to a significant waste of memory.
  

• */
  

• delta = max_t(unsigned long long, delta, min(freeable, batch_size));
• total_scan += delta; if (total_scan < 0) { pr_err("shrink_slab: %pF negative objects to delete nr=%ld\n",

I've queued it up for 4.18.

-- Thanks, Sasha