Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937361AbZAPTQS (ORCPT ); Fri, 16 Jan 2009 14:16:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759294AbZAPTP7 (ORCPT ); Fri, 16 Jan 2009 14:15:59 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:35826 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753226AbZAPTP6 (ORCPT ); Fri, 16 Jan 2009 14:15:58 -0500 Date: Fri, 16 Jan 2009 14:15:55 -0500 (EST) From: Steven Rostedt X-X-Sender: rostedt@gandalf.stny.rr.com To: Arnaldo Carvalho de Melo cc: Jens Axboe , Ingo Molnar , Frederic Weisbecker , linux-kernel@vger.kernel.org Subject: Re: [RFC][PATCH] ftrace interface for blktrace In-Reply-To: <20090116181611.GE6562@ghostprotocols.net> Message-ID: References: <20090116181611.GE6562@ghostprotocols.net> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1869 Lines: 54 Arnaldo, Cool stuff! On Fri, 16 Jan 2009, Arnaldo Carvalho de Melo wrote: > Hi Jens, > > The patch below adds a ftrace interface for blktrace, allowing > people to use it without any required userspace tools, using sysfs to setup the > act_mask, pid, start_lba, end_lba. > > Example usage: > > [root@f10-1 ~]# mount -t debugfs none /sys/kernel/debug/ I think you are the only person that mounts debugfs on the "official" location ;-) > [root@f10-1 ~]# ls /sys/block/sda/sda1/trace/ > act_mask enable end_lba pid start_lba > [root@f10-1 ~]# cat /sys/kernel/debug/tracing/available_tracers > blk function_graph wakeup function sched_switch nop > [root@f10-1 ~]# echo blk > /sys/kernel/debug/tracing/current_tracer You must like to type. -- Steve > [root@f10-1 ~]# cat /sys/kernel/debug/tracing/trace > # tracer: blk > # > # DEV CPU TIMESTAMP PID ACT FLG > # | | | | | | > [root@f10-1 ~]# echo 1 > /sys/block/sda/sda1/trace/enable > [root@f10-1 ~]# tail /sys/kernel/debug/tracing/trace > 8,1 0 143.070085 1208 P NS [tail] > 8,1 0 143.070087 1208 I RBS 4154375 + 8 [tail] > 8,1 0 143.070091 1208 A WBS 4155391 + 16 <- (8,1) 4155328 > 8,1 0 143.070091 1208 Q R 4155391 + 16 [tail] > 8,1 0 143.070094 1208 G RB 4155391 + 16 [tail] > 8,1 0 143.070094 1208 I RBS 4155391 + 16 [tail] > 8,1 0 143.070097 1208 U WS [tail] 2 > 8,1 0 143.070101 1208 D WB 4154375 + 8 [tail] > 8,1 0 143.070341 1208 D WB 4155391 + 16 [tail] > 8,1 0 143.070635 0 C RS 4154375 + 8 [0] > [root@f10-1 ~]# > -- 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/