Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266459AbUIOPb1 (ORCPT ); Wed, 15 Sep 2004 11:31:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266467AbUIOPb0 (ORCPT ); Wed, 15 Sep 2004 11:31:26 -0400 Received: from facesaver.epoch.ncsc.mil ([144.51.25.10]:60363 "EHLO epoch.ncsc.mil") by vger.kernel.org with ESMTP id S266459AbUIOPbM (ORCPT ); Wed, 15 Sep 2004 11:31:12 -0400 Subject: Re: [patch] voluntary-preempt-2.6.9-rc1-bk4-R1 From: Stephen Smalley To: Ingo Molnar Cc: Mark_H_Johnson@raytheon.com, Eric St-Laurent , Free Ekanayaka , free78@tin.it, "K.R. Foley" , linux-kernel , Felipe Alfaro Solana , luke@audioslack.com, nando@ccrma.stanford.edu, "P.O. Gaillard" , Daniel Schmitt , Lee Revell In-Reply-To: <20040914183202.GA20316@elte.hu> References: <20040914183202.GA20316@elte.hu> Content-Type: text/plain Organization: National Security Agency Message-Id: <1095262011.28981.192.camel@moss-spartans.epoch.ncsc.mil> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 (1.4.6-2) Date: Wed, 15 Sep 2004 11:26:51 -0400 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1323 Lines: 26 On Tue, 2004-09-14 at 14:32, Ingo Molnar wrote: > it seems a bit odd. avc_has_perm_noaudit() calls avc_insert(), and from > the entry to avc_insert(), to the memcpy() call done by > avc_has_perm_noaudit() there were 204 usecs spent. That's alot of time - > 175 thousand cycles! Now if you check out the code between line 1009 and > 1019 in security/selinux/avc.c, there's little that could cause this > amount of overhead. avc_insert() itself is rather simple - it does an > avc_claim_node() call which is an inlined function so it doesnt show up > in the trace. That function _might_ have called acv_reclaim_node() which > seems to do a linear scan over a list - i dont know how long that list > is typically but it could be long. Could you add "#define inline" near > the top of avc.c (but below the #include lines) so that we can see how > the overhead is distributed in the future? May be rendered moot by the RCU patches for SELinux, see http://marc.theaimsgroup.com/?l=linux-kernel&m=109386501021596&w=2 -- Stephen Smalley National Security Agency - 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/