From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754925Ab0DNKBu (ORCPT ); Wed, 14 Apr 2010 06:01:50 -0400 Received: from mail-yx0-f199.google.com ([209.85.210.199]:43182 "EHLO mail-yx0-f199.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754488Ab0DNKBs convert rfc822-to-8bit (ORCPT ); Wed, 14 Apr 2010 06:01:48 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=sR4P5UN9X+FMkQtW44Wuc7mpvb6fImakSRQvaZ5q76Gq29H6GikNB/k8X0UkesOH+L VMAC4EEvsBqcQ8XtfPsg06ASm6XCiEb1TWObOT365dXoAVhScHSlprpsuTmLTQYhdXcz 2xZT7PFkepTZHBMyK2ic8oGQyKbMWfLKBChGk= MIME-Version: 1.0 In-Reply-To: <20100414184213.f6bf11a7.kamezawa.hiroyu@jp.fujitsu.com> References: <20100414135945.2b0a1e0d.kamezawa.hiroyu@jp.fujitsu.com> <20100414054144.GH2493@dastard> <20100414145056.D147.A69D9226@jp.fujitsu.com> <20100414184213.f6bf11a7.kamezawa.hiroyu@jp.fujitsu.com> Date: Wed, 14 Apr 2010 19:01:47 +0900 Message-ID: Subject: Re: [PATCH] mm: disallow direct reclaim page writeback From: Minchan Kim To: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro , Dave Chinner , Chris Mason , Mel Gorman , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org 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 On Wed, Apr 14, 2010 at 6:42 PM, KAMEZAWA Hiroyuki wrote: > On Wed, 14 Apr 2010 16:19:02 +0900 > Minchan Kim wrote: > >> On Wed, Apr 14, 2010 at 3:13 PM, Minchan Kim wrote: >> > On Wed, Apr 14, 2010 at 2:54 PM, KOSAKI Motohiro >> > wrote: >> >>> On Wed, Apr 14, 2010 at 01:59:45PM +0900, KAMEZAWA Hiroyuki wrote: >> >>> > On Wed, 14 Apr 2010 11:40:41 +1000 >> >>> > Dave Chinner wrote: >> >>> > >> >>> > >  50)     3168      64   xfs_vm_writepage+0xab/0x160 [xfs] >> >>> > >  51)     3104     384   shrink_page_list+0x65e/0x840 >> >>> > >  52)     2720     528   shrink_zone+0x63f/0xe10 >> >>> > >> >>> > A bit OFF TOPIC. >> >>> > >> >>> > Could you share disassemble of shrink_zone() ? >> >>> > >> >>> > In my environ. >> >>> > 00000000000115a0 : >> >>> >    115a0:       55                      push   %rbp >> >>> >    115a1:       48 89 e5                mov    %rsp,%rbp >> >>> >    115a4:       41 57                   push   %r15 >> >>> >    115a6:       41 56                   push   %r14 >> >>> >    115a8:       41 55                   push   %r13 >> >>> >    115aa:       41 54                   push   %r12 >> >>> >    115ac:       53                      push   %rbx >> >>> >    115ad:       48 83 ec 78             sub    $0x78,%rsp >> >>> >    115b1:       e8 00 00 00 00          callq  115b6 >> >>> >    115b6:       48 89 75 80             mov    %rsi,-0x80(%rbp) >> >>> > >> >>> > disassemble seems to show 0x78 bytes for stack. And no changes to %rsp >> >>> > until retrun. >> >>> >> >>> I see the same. I didn't compile those kernels, though. IIUC, >> >>> they were built through the Ubuntu build infrastructure, so there is >> >>> something different in terms of compiler, compiler options or config >> >>> to what we are both using. Most likely it is the compiler inlining, >> >>> though Chris's patches to prevent that didn't seem to change the >> >>> stack usage. >> >>> >> >>> I'm trying to get a stack trace from the kernel that has shrink_zone >> >>> in it, but I haven't succeeded yet.... >> >> >> >> I also got 0x78 byte stack usage. Umm.. Do we discussed real issue now? >> >> >> > >> > In my case, 0x110 byte in 32 bit machine. >> > I think it's possible in 64 bit machine. >> > >> > 00001830 : >> >    1830:       55                      push   %ebp >> >    1831:       89 e5                   mov    %esp,%ebp >> >    1833:       57                      push   %edi >> >    1834:       56                      push   %esi >> >    1835:       53                      push   %ebx >> >    1836:       81 ec 10 01 00 00       sub    $0x110,%esp >> >    183c:       89 85 24 ff ff ff       mov    %eax,-0xdc(%ebp) >> >    1842:       89 95 20 ff ff ff       mov    %edx,-0xe0(%ebp) >> >    1848:       89 8d 1c ff ff ff       mov    %ecx,-0xe4(%ebp) >> >    184e:       8b 41 04                mov    0x4(%ecx) >> > >> > my gcc is following as. >> > >> > barrios@barriostarget:~/mmotm$ gcc -v >> > Using built-in specs. >> > Target: i486-linux-gnu >> > Configured with: ../src/configure -v --with-pkgversion='Ubuntu >> > 4.3.3-5ubuntu4' >> > --with-bugurl=file:///usr/share/doc/gcc-4.3/README.Bugs >> > --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr >> > --enable-shared --with-system-zlib --libexecdir=/usr/lib >> > --without-included-gettext --enable-threads=posix --enable-nls >> > --with-gxx-include-dir=/usr/include/c++/4.3 --program-suffix=-4.3 >> > --enable-clocale=gnu --enable-libstdcxx-debug --enable-objc-gc >> > --enable-mpfr --enable-targets=all --with-tune=generic >> > --enable-checking=release --build=i486-linux-gnu --host=i486-linux-gnu >> > --target=i486-linux-gnu >> > Thread model: posix >> > gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4) >> > >> > >> > Is it depends on config? >> > I attach my config. >> >> I changed shrink list by noinline_for_stack. >> The result is following as. >> >> >> 00001fe0 : >>     1fe0:       55                      push   %ebp >>     1fe1:       89 e5                   mov    %esp,%ebp >>     1fe3:       57                      push   %edi >>     1fe4:       56                      push   %esi >>     1fe5:       53                      push   %ebx >>     1fe6:       83 ec 4c                sub    $0x4c,%esp >>     1fe9:       89 45 c0                mov    %eax,-0x40(%ebp) >>     1fec:       89 55 bc                mov    %edx,-0x44(%ebp) >>     1fef:       89 4d b8                mov    %ecx,-0x48(%ebp) >> >> 0x110 -> 0x4c. >> >> Should we have to add noinline_for_stack for shrink_list? >> > > Hmm. about shirnk_zone(), I don't think uninlining functions directly called > by shrink_zone() can be a help. > Total stack size of call-chain will be still big. Absolutely. But above 500 byte usage is one of hogger and uninlining is not critical about reclaim performance. So I think we don't get any lost than gain. But I don't get in a hurry. adhoc approach is not good. I hope when Mel tackles down consumption of stack in reclaim path, he modifies this part, too. Thanks. > Thanks, > -Kame > > > -- Kind regards, Minchan Kim