lkml.org 
[lkml]   [2016]   [Sep]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 2/4] mm, compaction: more reliably increase direct compaction priority
On Fri 23-09-16 08:55:33, Vlastimil Babka wrote:
[...]
> >From 1623d5bd441160569ffad3808aeeec852048e558 Mon Sep 17 00:00:00 2001
> From: Vlastimil Babka <vbabka@suse.cz>
> Date: Thu, 22 Sep 2016 17:02:37 +0200
> Subject: [PATCH] mm, page_alloc: pull no_progress_loops update to
> should_reclaim_retry()
>
> The should_reclaim_retry() makes decisions based on no_progress_loops, so it
> makes sense to also update the counter there. It will be also consistent with
> should_compact_retry() and compaction_retries. No functional change.
>
> [hillf.zj@alibaba-inc.com: fix missing pointer dereferences]
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>

OK, this looks reasonable to me. Could you post both patches in a
separate thread please? They shouldn't be really needed to mitigate the
pre-mature oom killer issues. Feel free to add
Acked-by: Michal Hocko <mhocko@suse.com>

Thanks!

> ---
> mm/page_alloc.c | 28 ++++++++++++++--------------
> 1 file changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 582820080601..6039ff40452c 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -3401,16 +3401,26 @@ bool gfp_pfmemalloc_allowed(gfp_t gfp_mask)
> static inline bool
> should_reclaim_retry(gfp_t gfp_mask, unsigned order,
> struct alloc_context *ac, int alloc_flags,
> - bool did_some_progress, int no_progress_loops)
> + bool did_some_progress, int *no_progress_loops)
> {
> struct zone *zone;
> struct zoneref *z;
>
> /*
> + * Costly allocations might have made a progress but this doesn't mean
> + * their order will become available due to high fragmentation so
> + * always increment the no progress counter for them
> + */
> + if (did_some_progress && order <= PAGE_ALLOC_COSTLY_ORDER)
> + *no_progress_loops = 0;
> + else
> + (*no_progress_loops)++;
> +
> + /*
> * Make sure we converge to OOM if we cannot make any progress
> * several times in the row.
> */
> - if (no_progress_loops > MAX_RECLAIM_RETRIES)
> + if (*no_progress_loops > MAX_RECLAIM_RETRIES)
> return false;
>
> /*
> @@ -3425,7 +3435,7 @@ should_reclaim_retry(gfp_t gfp_mask, unsigned order,
> unsigned long reclaimable;
>
> available = reclaimable = zone_reclaimable_pages(zone);
> - available -= DIV_ROUND_UP(no_progress_loops * available,
> + available -= DIV_ROUND_UP((*no_progress_loops) * available,
> MAX_RECLAIM_RETRIES);
> available += zone_page_state_snapshot(zone, NR_FREE_PAGES);
>
> @@ -3641,18 +3651,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
> if (order > PAGE_ALLOC_COSTLY_ORDER && !(gfp_mask & __GFP_REPEAT))
> goto nopage;
>
> - /*
> - * Costly allocations might have made a progress but this doesn't mean
> - * their order will become available due to high fragmentation so
> - * always increment the no progress counter for them
> - */
> - if (did_some_progress && order <= PAGE_ALLOC_COSTLY_ORDER)
> - no_progress_loops = 0;
> - else
> - no_progress_loops++;
> -
> if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags,
> - did_some_progress > 0, no_progress_loops))
> + did_some_progress > 0, &no_progress_loops))
> goto retry;
>
> /*
> --
> 2.10.0
>
>
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to majordomo@kvack.org. For more info on Linux MM,
> see: http://www.linux-mm.org/ .
> Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

--
Michal Hocko
SUSE Labs

\
 
 \ /
  Last update: 2016-09-23 10:23    [W:0.054 / U:0.824 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site