Re: FAILED: patch "[PATCH] mm/compaction.c: clear total_{migrate,free}_scanned before" failed to apply to 4.19-stable tree

[Sasha Levin <sashal@kernel.org>]

On Thu, Oct 03, 2019 at 01:38:46PM +0200, gregkh@linuxfoundation.org wrote:
>
>The patch below does not apply to the 4.19-stable tree.
>If someone wants it applied there, or to any other stable or longterm
>tree, then please email the backport, including the original git commit
>id to <stable@vger.kernel.org>.
>
>thanks,
>
>greg k-h
>
>------------------ original commit in Linus's tree ------------------
>
>From a94b525241c0fff3598809131d7cfcfe1d572d8c Mon Sep 17 00:00:00 2001
>From: Yafang Shao <laoar.shao@gmail.com>
>Date: Mon, 23 Sep 2019 15:36:54 -0700
>Subject: [PATCH] mm/compaction.c: clear total_{migrate,free}_scanned before
> scanning a new zone
>
>total_{migrate,free}_scanned will be added to COMPACTMIGRATE_SCANNED and
>COMPACTFREE_SCANNED in compact_zone().  We should clear them before
>scanning a new zone.  In the proc triggered compaction, we forgot clearing
>them.
>
>[laoar.shao@gmail.com: introduce a helper compact_zone_counters_init()]
>  Link: http://lkml.kernel.org/r/1563869295-25748-1-git-send-email-laoar.shao@gmail.com
>[akpm@linux-foundation.org: expand compact_zone_counters_init() into its single callsite, per mhocko]
>[vbabka@suse.cz: squash compact_zone() list_head init as well]
>  Link: http://lkml.kernel.org/r/1fb6f7da-f776-9e42-22f8-bbb79b030b98@suse.cz
>[akpm@linux-foundation.org: kcompactd_do_work(): avoid unnecessary initialization of cc.zone]
>Link: http://lkml.kernel.org/r/1563789275-9639-1-git-send-email-laoar.shao@gmail.com
>Fixes: 7f354a548d1c ("mm, compaction: add vmstats for kcompactd work")
>Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
>Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
>Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
>Cc: David Rientjes <rientjes@google.com>
>Cc: Yafang Shao <shaoyafang@didiglobal.com>
>Cc: Mel Gorman <mgorman@techsingularity.net>
>Cc: Michal Hocko <mhocko@suse.com>
>Cc: <stable@vger.kernel.org>
>Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
>Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This was mostly due to unrelated code cleanups. I've queued up a
backport for 4.19 and 4.14, it's not needed on older kernels.

--
Thanks,
Sasha