Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753268AbbDMHC1 (ORCPT ); Mon, 13 Apr 2015 03:02:27 -0400 Received: from mail-wg0-f53.google.com ([74.125.82.53]:33993 "EHLO mail-wg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751594AbbDMHCY convert rfc822-to-8bit (ORCPT ); Mon, 13 Apr 2015 03:02:24 -0400 MIME-Version: 1.0 X-Originating-IP: [212.25.79.130] In-Reply-To: <20150307001816.GA2850@udknight> References: <20150307001816.GA2850@udknight> From: Leon Romanovsky Date: Mon, 13 Apr 2015 10:02:02 +0300 Message-ID: Subject: Re: [PATCH RESEND] block:bounce: fix call inc_|dec_zone_page_state on different pages confuse value of NR_BOUNCE To: Wang YanQing , axboe@kernel.dk, "linux-kernel@vger.kernel.org" , Linux-MM Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5221 Lines: 85 On Sat, Mar 7, 2015 at 2:18 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 call inc_|dec_zone_page_state on different pages, then different Minor typo "call call" => "call" > zones, and cause we get confusion value of NR_BOUNCE. I suggest to rephrase the "and cause we get confusion value" to be "and cause us to get unexpected value". > > 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 > --- > I find previous email can't be "git am" properly, > so resend it. > > Thanks. > > 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; > -- > 2.2.2.dirty > > -- > 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: email@kvack.org -- Leon Romanovsky | Independent Linux Consultant www.leon.nu | leon@leon.nu -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/