Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261403AbUKGQ4a (ORCPT ); Sun, 7 Nov 2004 11:56:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261648AbUKGQ4a (ORCPT ); Sun, 7 Nov 2004 11:56:30 -0500 Received: from probity.mcc.ac.uk ([130.88.200.94]:8200 "EHLO probity.mcc.ac.uk") by vger.kernel.org with ESMTP id S261403AbUKGQ40 (ORCPT ); Sun, 7 Nov 2004 11:56:26 -0500 Date: Sun, 7 Nov 2004 16:56:23 +0000 From: John Levon To: Chris Wright Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, cliffw@osdl.org Subject: Re: [PATCH][OPROFILE] disable preempt when calling smp_processor_id() Message-ID: <20041107165623.GA36328@compsoc.man.ac.uk> References: <20041105163221.J14339@build.pdx.osdl.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20041105163221.J14339@build.pdx.osdl.net> User-Agent: Mutt/1.3.25i X-Url: http://www.movementarian.org/ X-Record: Graham Coxon - Happiness in Magazines X-Scanner: exiscan for exim4 (http://duncanthrax.net/exiscan/) *1CQqL3-0000MD-Al*xC5Fqh0zgtA* Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1289 Lines: 39 On Fri, Nov 05, 2004 at 04:32:21PM -0800, Chris Wright wrote: > smp_processor_id() is called w/out preempt disabled. Use > get_cpu()/put_cpu() instead. Should this be put_cpu_no_resched()? No, the patch below looks fine regards john > Signed-off-by: Chris Wright > > --- linux-2.6.10-rc1-mm3-smp_processor_id/drivers/oprofile/buffer_sync.c~orig 2004-11-05 15:21:21.551984200 -0800 > +++ linux-2.6.10-rc1-mm3-smp_processor_id/drivers/oprofile/buffer_sync.c 2004-11-05 15:23:29.000000000 -0800 > @@ -62,7 +62,8 @@ > /* To avoid latency problems, we only process the current CPU, > * hoping that most samples for the task are on this CPU > */ > - sync_buffer(smp_processor_id()); > + sync_buffer(get_cpu()); > + put_cpu(); > return 0; > } > > @@ -86,7 +87,8 @@ > /* To avoid latency problems, we only process the current CPU, > * hoping that most samples for the task are on this CPU > */ > - sync_buffer(smp_processor_id()); > + sync_buffer(get_cpu()); > + put_cpu(); > return 0; > } > - 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/