From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932241AbZH0Cc4 (ORCPT ); Wed, 26 Aug 2009 22:32:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932215AbZH0Ccz (ORCPT ); Wed, 26 Aug 2009 22:32:55 -0400 Received: from mail-ew0-f206.google.com ([209.85.219.206]:54351 "EHLO mail-ew0-f206.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932237AbZH0Ccw (ORCPT ); Wed, 26 Aug 2009 22:32:52 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references :mime-version:content-type:content-transfer-encoding; b=GRGAYrWl5APNjO5ew+H2X82mmZNJ8ZAGXMwR1ndVU4wv8nR+1uBgn9GF/Z1pw9aqdi pFq9vUPnBOP16NK0akfnNptAjfiZDroJPu9sjlswuj9gWwqWiu2VLGq+k1IwTbAAz+m9 8ZDhDMltvipMifs6PhI7ua5T6WulRmIDTAXMk= From: Frederic Weisbecker To: Ingo Molnar Cc: LKML , Masami Hiramatsu , Ananth N Mavinakayanahalli , Avi Kivity , Andi Kleen , Christoph Hellwig , "Frank Ch. Eigler" , "H. Peter Anvin" , Ingo Molnar , Jason Baron , Jim Keniston , "K.Prasad" , Lai Jiangshan , Li Zefan , =?utf-8?q?Przemys=C5=82aw=20Pawe=C5=82czyk?= , Roland McGrath , Sam Ravnborg , Srikar Dronamraju , Steven Rostedt , Tom Zanussi , Vegard Nossum , Frederic Weisbecker Subject: [PATCH 13/18] tracing: Add kprobes event profiling interface Date: Thu, 27 Aug 2009 04:32:12 +0200 Message-Id: <1251340337-5640-14-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 1.6.2.3 In-Reply-To: <1251340337-5640-1-git-send-email-fweisbec@gmail.com> References: <1251340337-5640-1-git-send-email-fweisbec@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Masami Hiramatsu Add profiling interfaces for each kprobes event. This interface provides how many times each probe hit or missed. Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Avi Kivity Cc: Andi Kleen Cc: Christoph Hellwig Cc: Frank Ch. Eigler Cc: H. Peter Anvin Cc: Ingo Molnar Cc: Jason Baron Cc: Jim Keniston Cc: K.Prasad Cc: Lai Jiangshan Cc: Li Zefan Cc: Przemysław Pawełczyk Cc: Roland McGrath Cc: Sam Ravnborg Cc: Srikar Dronamraju Cc: Steven Rostedt Cc: Tom Zanussi Cc: Vegard Nossum LKML-Reference: <20090813203541.31965.8452.stgit@localhost.localdomain> Signed-off-by: Frederic Weisbecker --- Documentation/trace/kprobetrace.txt | 8 ++++++ kernel/trace/trace_kprobe.c | 43 +++++++++++++++++++++++++++++++++++ 2 files changed, 51 insertions(+), 0 deletions(-) diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt index 5e59e85..3de7517 100644 --- a/Documentation/trace/kprobetrace.txt +++ b/Documentation/trace/kprobetrace.txt @@ -70,6 +70,14 @@ filter: names and field names for describing filters. +Event Profiling +--------------- + You can check the total number of probe hits and probe miss-hits via +/sys/kernel/debug/tracing/kprobe_profile. + The first column is event name, the second is the number of probe hits, +the third is the number of probe miss-hits. + + Usage examples -------------- To add a probe as a new event, write a new definition to kprobe_events diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 9c067bf..ce68197 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -184,6 +184,7 @@ struct trace_probe { struct kprobe kp; struct kretprobe rp; }; + unsigned long nhit; const char *symbol; /* symbol name */ struct ftrace_event_call call; struct trace_event event; @@ -781,6 +782,37 @@ static const struct file_operations kprobe_events_ops = { .write = probes_write, }; +/* Probes profiling interfaces */ +static int probes_profile_seq_show(struct seq_file *m, void *v) +{ + struct trace_probe *tp = v; + + seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit, + probe_is_return(tp) ? tp->rp.kp.nmissed : tp->kp.nmissed); + + return 0; +} + +static const struct seq_operations profile_seq_op = { + .start = probes_seq_start, + .next = probes_seq_next, + .stop = probes_seq_stop, + .show = probes_profile_seq_show +}; + +static int profile_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &profile_seq_op); +} + +static const struct file_operations kprobe_profile_ops = { + .owner = THIS_MODULE, + .open = profile_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + /* Kprobe handler */ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) { @@ -791,6 +823,8 @@ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) unsigned long irq_flags; struct ftrace_event_call *call = &tp->call; + tp->nhit++; + local_save_flags(irq_flags); pc = preempt_count(); @@ -1140,9 +1174,18 @@ static __init int init_kprobe_trace(void) entry = debugfs_create_file("kprobe_events", 0644, d_tracer, NULL, &kprobe_events_ops); + /* Event list interface */ if (!entry) pr_warning("Could not create debugfs " "'kprobe_events' entry\n"); + + /* Profile interface */ + entry = debugfs_create_file("kprobe_profile", 0444, d_tracer, + NULL, &kprobe_profile_ops); + + if (!entry) + pr_warning("Could not create debugfs " + "'kprobe_profile' entry\n"); return 0; } fs_initcall(init_kprobe_trace); -- 1.6.2.3