From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754663AbYACR5F (ORCPT ); Thu, 3 Jan 2008 12:57:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751632AbYACR4z (ORCPT ); Thu, 3 Jan 2008 12:56:55 -0500 Received: from tomts40.bellnexxia.net ([209.226.175.97]:62805 "EHLO tomts40-srv.bellnexxia.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751343AbYACR4x (ORCPT ); Thu, 3 Jan 2008 12:56:53 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Ah4FABWwfEdMROHU/2dsb2JhbACBV6hl Date: Thu, 3 Jan 2008 12:56:50 -0500 From: Mathieu Desnoyers To: Steven Rostedt Cc: LKML , Ingo Molnar , Linus Torvalds , Andrew Morton , Peter Zijlstra , Christoph Hellwig , Gregory Haskins , Arnaldo Carvalho de Melo , "William L. Irwin" , Steven Rostedt Subject: Re: [RFC PATCH 10/11] mcount tracer show task comm and pid Message-ID: <20080103175650.GE30582@Krystal> References: <20080103071609.478486470@goodmis.org> <20080103072228.212967487@goodmis.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <20080103072228.212967487@goodmis.org> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.21.3-grsec (i686) X-Uptime: 12:55:40 up 60 days, 23:01, 6 users, load average: 0.40, 0.46, 0.50 User-Agent: Mutt/1.5.16 (2007-06-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Steven Rostedt (rostedt@goodmis.org) wrote: > This adds the task comm and pid to the trace output. This gives the > output like: > > CPU 0: sshd:2605 [] remove_wait_queue+0xc/0x4a <-- [] free_poll_entry+0x1e/0x2a > CPU 2: bash:2610 [] tty_check_change+0x9/0xb6 <-- [] tty_ioctl+0x59f/0xcdd > CPU 0: sshd:2605 [] _spin_lock_irqsave+0xe/0x81 <-- [] remove_wait_queue+0x17/0x4a > CPU 2: bash:2610 [] find_vpid+0x9/0x24 <-- [] tty_ioctl+0x62f/0xcdd > CPU 0: sshd:2605 [] _spin_unlock_irqrestore+0x9/0x3a <-- [] remove_wait_queue+0x45/0x4a > CPU 0: sshd:2605 [] fput+0x9/0x1b <-- [] free_poll_entry+0x26/0x2a > > > Signed-off-by: Steven Rostedt > --- > lib/mcount/tracer.c | 6 +++++- > lib/mcount/tracer.h | 3 +++ > 2 files changed, 8 insertions(+), 1 deletion(-) > > Index: linux-compile.git/lib/mcount/tracer.c > =================================================================== > --- linux-compile.git.orig/lib/mcount/tracer.c 2008-01-02 23:17:21.000000000 -0500 > +++ linux-compile.git/lib/mcount/tracer.c 2008-01-02 23:17:44.000000000 -0500 > @@ -34,6 +34,7 @@ mctracer_add_trace_entry(struct mctracer > { > unsigned long idx, idx_next; > struct mctracer_entry *entry; > + struct task_struct *tsk = current; Aren't there situations, like in the middle of a context switch, where current is not valid ? Is also poses a problem for early boot, and NMI tracing. > > idx = tr->trace_idx[cpu]; > idx_next = idx + 1; > @@ -52,6 +53,8 @@ mctracer_add_trace_entry(struct mctracer > entry->idx = atomic_inc_return(&tr->cnt); > entry->ip = ip; > entry->parent_ip = parent_ip; > + entry->pid = tsk->pid; > + memcpy(entry->comm, tsk->comm, TASK_COMM_LEN); > } > > static inline notrace void trace_function(const unsigned long ip, > @@ -223,7 +226,8 @@ static int s_show(struct seq_file *m, vo > return -1; > } > > - seq_printf(m, " CPU %d: ", iter->cpu); > + seq_printf(m, "CPU %d: ", iter->cpu); > + seq_printf(m, "%s:%d ", iter->ent->comm, iter->ent->pid); > seq_print_ip_sym(m, iter->ent->ip); > if (iter->ent->parent_ip) { > seq_printf(m, " <-- "); > Index: linux-compile.git/lib/mcount/tracer.h > =================================================================== > --- linux-compile.git.orig/lib/mcount/tracer.h 2008-01-02 23:16:15.000000000 -0500 > +++ linux-compile.git/lib/mcount/tracer.h 2008-01-02 23:17:44.000000000 -0500 > @@ -2,11 +2,14 @@ > #define _LINUX_MCOUNT_TRACER_H > > #include > +#include > > struct mctracer_entry { > unsigned long idx; > unsigned long ip; > unsigned long parent_ip; > + char comm[TASK_COMM_LEN]; > + pid_t pid; > }; > > struct mctracer_trace { > > -- -- Mathieu Desnoyers Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68