From: Jens Axboe <axboe@kernel.dk>
To: Wang YanQing <udknight@gmail.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
akpm@linux-foundation.org, leon@leon.nu
Subject: Re: [PATCH v2]block:bounce: fix call inc_|dec_zone_page_state on different pages confuse value of NR_BOUNCE
Date: Mon, 27 Apr 2015 09:24:27 -0600 [thread overview]
Message-ID: <553E54AB.9050801@kernel.dk> (raw)
In-Reply-To: <20150426084331.GA5680@udknight>
On 04/26/2015 02:43 AM, Wang YanQing wrote:
> Commit d2c5e30c9a1420902262aa923794d2ae4e0bc391
> ("[PATCH] zoned vm counters: conversion of nr_bounce to per zone counter")
> convert statistic of nr_bounce to per zone and one global value in vm_stat,
> but it call inc_|dec_zone_page_state on different pages, then different
> zones, and cause us to get unexpected value of NR_BOUNCE.
>
> Below is the result on my machine:
> Mar 2 09:26:08 udknight kernel: [144766.778265] Mem-Info:
> Mar 2 09:26:08 udknight kernel: [144766.778266] DMA per-cpu:
> Mar 2 09:26:08 udknight kernel: [144766.778268] CPU 0: hi: 0, btch: 1 usd: 0
> Mar 2 09:26:08 udknight kernel: [144766.778269] CPU 1: hi: 0, btch: 1 usd: 0
> Mar 2 09:26:08 udknight kernel: [144766.778270] Normal per-cpu:
> Mar 2 09:26:08 udknight kernel: [144766.778271] CPU 0: hi: 186, btch: 31 usd: 0
> Mar 2 09:26:08 udknight kernel: [144766.778273] CPU 1: hi: 186, btch: 31 usd: 0
> Mar 2 09:26:08 udknight kernel: [144766.778274] HighMem per-cpu:
> Mar 2 09:26:08 udknight kernel: [144766.778275] CPU 0: hi: 186, btch: 31 usd: 0
> Mar 2 09:26:08 udknight kernel: [144766.778276] CPU 1: hi: 186, btch: 31 usd: 0
> Mar 2 09:26:08 udknight kernel: [144766.778279] active_anon:46926 inactive_anon:287406 isolated_anon:0
> Mar 2 09:26:08 udknight kernel: [144766.778279] active_file:105085 inactive_file:139432 isolated_file:0
> Mar 2 09:26:08 udknight kernel: [144766.778279] unevictable:653 dirty:0 writeback:0 unstable:0
> Mar 2 09:26:08 udknight kernel: [144766.778279] free:178957 slab_reclaimable:6419 slab_unreclaimable:9966
> Mar 2 09:26:08 udknight kernel: [144766.778279] mapped:4426 shmem:305277 pagetables:784 bounce:0
> Mar 2 09:26:08 udknight kernel: [144766.778279] free_cma:0
> Mar 2 09:26:08 udknight kernel: [144766.778286] DMA free:3324kB min:68kB low:84kB high:100kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15976kB managed:15900kB mlocked:0kB dirty:0kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:0kB slab_unreclaimable:0kB kernel_stack:0kB pagetables:0kB unstable:0kB bounce:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes
> Mar 2 09:26:08 udknight kernel: [144766.778287] lowmem_reserve[]: 0 822 3754 3754
> Mar 2 09:26:08 udknight kernel: [144766.778293] Normal free:26828kB min:3632kB low:4540kB high:5448kB active_anon:4872kB inactive_anon:68kB active_file:1796kB inactive_file:1796kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:892920kB managed:842560kB mlocked:0kB dirty:0kB writeback:0kB mapped:0kB shmem:4144kB slab_reclaimable:25676kB slab_unreclaimable:39864kB kernel_stack:1944kB pagetables:3136kB unstable:0kB bounce:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:2412612 all_unreclaimable? yes
> Mar 2 09:26:08 udknight kernel: [144766.778294] lowmem_reserve[]: 0 0 23451 23451
> Mar 2 09:26:08 udknight kernel: [144766.778299] HighMem free:685676kB min:512kB low:3748kB high:6984kB active_anon:182832kB inactive_anon:1149556kB active_file:418544kB inactive_file:555932kB unevictable:2612kB isolated(anon):0kB isolated(file):0kB present:3001732kB managed:3001732kB mlocked:0kB dirty:0kB writeback:0kB mapped:17704kB shmem:1216964kB slab_reclaimable:0kB slab_unreclaimable:0kB kernel_stack:0kB pagetables:0kB unstable:0kB bounce:75771152kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no
> Mar 2 09:26:08 udknight kernel: [144766.778300] lowmem_reserve[]: 0 0 0 0
>
> You can see bounce:75771152kB for HighMem, but bounce:0 for lowmem and global.
>
> This patch fix it.
>
> Signed-off-by: Wang YanQing <udknight@gmail.com>
> ---
> Changes
> v1-v2: fix comment issue reported by Leon Romanovsky
>
> block/bounce.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/block/bounce.c b/block/bounce.c
> index ab21ba2..ed9dd80 100644
> --- a/block/bounce.c
> +++ b/block/bounce.c
> @@ -221,8 +221,8 @@ bounce:
> if (page_to_pfn(page) <= queue_bounce_pfn(q) && !force)
> continue;
>
> - inc_zone_page_state(to->bv_page, NR_BOUNCE);
> to->bv_page = mempool_alloc(pool, q->bounce_gfp);
> + inc_zone_page_state(to->bv_page, NR_BOUNCE);
>
> if (rw == WRITE) {
> char *vto, *vfrom;
Applied, thanks.
--
Jens Axboe
--
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>
next prev parent reply other threads:[~2015-04-27 15:24 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-26 8:43 [PATCH v2]block:bounce: fix call inc_|dec_zone_page_state on different pages confuse value of NR_BOUNCE Wang YanQing
2015-04-27 15:24 ` Jens Axboe [this message]
-- strict thread matches above, loose matches on Subject: below --
2015-04-27 0:51 Wang YanQing
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=553E54AB.9050801@kernel.dk \
--to=axboe@kernel.dk \
--cc=akpm@linux-foundation.org \
--cc=leon@leon.nu \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=udknight@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).