From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755156Ab0BNJJY (ORCPT ); Sun, 14 Feb 2010 04:09:24 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:37902 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752764Ab0BNJJW (ORCPT ); Sun, 14 Feb 2010 04:09:22 -0500 Date: Sun, 14 Feb 2010 10:09:13 +0100 From: Ingo Molnar To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, Steven Rostedt , Fr??d??ric Weisbecker , Andrew Morton Subject: [GIT PULL] tracing fixes Message-ID: <20100214090913.GA26388@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -2.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, Please pull the latest tracing-fixes-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git tracing-fixes-for-linus Thanks, Ingo ------------------> Heiko Carstens (1): tracing/kprobes: Fix probe parsing Lai Jiangshan (1): tracing: Fix circular dead lock in stack trace kernel/trace/trace_kprobe.c | 2 +- kernel/trace/trace_stack.c | 24 ++++++++++++++++++++++++ 2 files changed, 25 insertions(+), 1 deletions(-) diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 6ea90c0..50b1b82 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -689,7 +689,7 @@ static int create_trace_probe(int argc, char **argv) return -EINVAL; } /* an address specified */ - ret = strict_strtoul(&argv[0][2], 0, (unsigned long *)&addr); + ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr); if (ret) { pr_info("Failed to parse address.\n"); return ret; diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index 678a512..f4bc9b2 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -157,6 +157,7 @@ stack_max_size_write(struct file *filp, const char __user *ubuf, unsigned long val, flags; char buf[64]; int ret; + int cpu; if (count >= sizeof(buf)) return -EINVAL; @@ -171,9 +172,20 @@ stack_max_size_write(struct file *filp, const char __user *ubuf, return ret; local_irq_save(flags); + + /* + * In case we trace inside arch_spin_lock() or after (NMI), + * we will cause circular lock, so we also need to increase + * the percpu trace_active here. + */ + cpu = smp_processor_id(); + per_cpu(trace_active, cpu)++; + arch_spin_lock(&max_stack_lock); *ptr = val; arch_spin_unlock(&max_stack_lock); + + per_cpu(trace_active, cpu)--; local_irq_restore(flags); return count; @@ -206,7 +218,13 @@ t_next(struct seq_file *m, void *v, loff_t *pos) static void *t_start(struct seq_file *m, loff_t *pos) { + int cpu; + local_irq_disable(); + + cpu = smp_processor_id(); + per_cpu(trace_active, cpu)++; + arch_spin_lock(&max_stack_lock); if (*pos == 0) @@ -217,7 +235,13 @@ static void *t_start(struct seq_file *m, loff_t *pos) static void t_stop(struct seq_file *m, void *p) { + int cpu; + arch_spin_unlock(&max_stack_lock); + + cpu = smp_processor_id(); + per_cpu(trace_active, cpu)--; + local_irq_enable(); }