[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <c1bd0983-219d-e279-2630-c38329e59140@redhat.com>
Date: Fri, 26 May 2023 21:36:21 +0200
From: David Hildenbrand <david@...hat.com>
To: "zhaoyang.huang" <zhaoyang.huang@...soc.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Matthew Wilcox <willy@...radead.org>,
Minchan Kim <minchan@...nel.org>,
Joonsoo Kim <iamjoonsoo.kim@....com>, linux-mm@...ck.org,
linux-kernel@...r.kernel.org,
Zhaoyang Huang <huangzhaoyang@...il.com>, ke.wang@...soc.com
Subject: Re: [PATCHv4] mm: skip CMA pages when they are not available
On 22.05.23 08:36, zhaoyang.huang wrote:
> From: Zhaoyang Huang <zhaoyang.huang@...soc.com>
>
> This patch fixes unproductive reclaiming of CMA pages by skipping them when they
> are not available for current context. It is arise from bellowing OOM issue, which
> caused by large proportion of MIGRATE_CMA pages among free pages.
>
> [ 36.172486] [03-19 10:05:52.172] ActivityManager: page allocation failure: order:0, mode:0xc00(GFP_NOIO), nodemask=(null),cpuset=foreground,mems_allowed=0
> [ 36.189447] [03-19 10:05:52.189] DMA32: 0*4kB 447*8kB (C) 217*16kB (C) 124*32kB (C) 136*64kB (C) 70*128kB (C) 22*256kB (C) 3*512kB (C) 0*1024kB 0*2048kB 0*4096kB = 35848kB
> [ 36.193125] [03-19 10:05:52.193] Normal: 231*4kB (UMEH) 49*8kB (MEH) 14*16kB (H) 13*32kB (H) 8*64kB (H) 2*128kB (H) 0*256kB 1*512kB (H) 0*1024kB 0*2048kB 0*4096kB = 3236kB
> ...
> [ 36.234447] [03-19 10:05:52.234] SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
> [ 36.234455] [03-19 10:05:52.234] cache: ext4_io_end, object size: 64, buffer size: 64, default order: 0, min order: 0
> [ 36.234459] [03-19 10:05:52.234] node 0: slabs: 53,objs: 3392, free: 0
>
> Signed-off-by: Zhaoyang Huang <zhaoyang.huang@...soc.com>
> ---
> v2: update commit message and fix build error when CONFIG_CMA is not set
> v3,v4: update code and comments
> ---
> ---
> mm/vmscan.c | 23 ++++++++++++++++++++++-
> 1 file changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index bd6637f..20facec 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -2193,6 +2193,26 @@ static __always_inline void update_lru_sizes(struct lruvec *lruvec,
>
> }
>
> +#ifdef CONFIG_CMA
> +/*
> + * It is waste of effort to scan and reclaim CMA pages if it is not available
> + * for current allocation context
> + */
/*
* Only movable allocations may end up on MIGRATE_CMA pageblocks. If
* we're not dealing with a movable allocation, it doesn't make sense to
* reclaim from these pageblocks: the reclaimed memory is unusable for
* this allocation.
*/
Did I get it right?
> +static bool skip_cma(struct folio *folio, struct scan_control *sc)
> +{
> + if (!current_is_kswapd() &&
> + gfp_migratetype(sc->gfp_mask) != MIGRATE_MOVABLE &&
> + get_pageblock_migratetype(&folio->page) == MIGRATE_CMA)
> + return true;
> + return false;
return !current_is_kswapd() &&
gfp_migratetype(sc->gfp_mask) != MIGRATE_MOVABLE &&
get_pageblock_migratetype(&folio->page) == MIGRATE_CMA;
--
Thanks,
David / dhildenb
Powered by blists - more mailing lists