From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from digeo-nav01.digeo.com (digeo-nav01.digeo.com [192.168.1.233]) by packet.digeo.com (8.9.3+Sun/8.9.3) with SMTP id WAA23801 for ; Thu, 19 Sep 2002 22:41:44 -0700 (PDT) Message-ID: <3D8AB518.218F8503@digeo.com> Date: Thu, 19 Sep 2002 22:41:44 -0700 From: Andrew Morton MIME-Version: 1.0 Subject: Re: [patch] remove page->virtual References: <3D8AAA58.41BC835F@digeo.com> <20020920050320.GH3530@holomorphy.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: William Lee Irwin III Cc: lkml , "linux-mm@kvack.org" List-ID: William Lee Irwin III wrote: > > On Thu, Sep 19, 2002 at 09:55:52PM -0700, Andrew Morton wrote: > > set_page_address() and page_address() implementations consume 0.4% and > > 1.3% of CPU time respectively. I think that's OK. (Plus the tested code > > was doing an unneeded lookup in set_page_address(), for debug purposes) > > Looks yummy. I'll take it for a spin tonight on my benchmark-o-matic. > Clearing some more air in ZONE_NORMAL is always welcome here. Ta. > On Thu, Sep 19, 2002 at 09:55:52PM -0700, Andrew Morton wrote: > > c01884f2 6914 10.5108 .text.lock.dir > > c01546b3 5847 8.88872 .text.lock.namei > > c01eb99e 3811 5.79355 .text.lock.dec_and_lock > > c01515dc 3775 5.73883 link_path_walk > > c015207c 3567 5.42262 path_lookup > > c015aba4 3194 4.85558 __d_lookup > > c01eb690 2814 4.2779 __generic_copy_to_user > > c01eb950 2562 3.8948 atomic_dec_and_lock > > c0187580 2473 3.7595 ext2_readdir > > c0155d3c 2172 3.30192 filldir64 > > c0151114 1786 2.71511 path_release > > c0145b6a 1753 2.66494 .text.lock.open > > What's going on here? fs stuff is really hurting. At any rate, the > overhead of the address calculation and hashtable lookup is microscopic > according to this, and I want space. c0182f90 5949 14.5552 ext2_readdir lock_kernel() c014f65c 5790 14.1662 path_lookup Confused. oprofile claims read_lock(¤t->fs->lock) but it's surely dcache_lock. c01e6e80 4275 10.4595 atomic_dec_and_lock dput/iput c014eba4 2264 5.53924 link_path_walk c0158050 1988 4.86397 __d_lookup c01426e8 1903 4.656 sys_chdir c01e6bc0 1735 4.24496 __generic_copy_to_user c015319c 1344 3.28831 filldir64 c014e6b4 1205 2.94823 path_release c0109070 1065 2.6057 system_call c014b934 929 2.27295 cp_new_stat64 c014b380 822 2.01116 generic_fillattr c0157250 712 1.74202 dput c014b3fc 622 1.52182 vfs_getattr c0157468 556 1.36034 dget_locked -- 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/