From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933082Ab3EGNlf (ORCPT ); Tue, 7 May 2013 09:41:35 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42356 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933059Ab3EGNla (ORCPT ); Tue, 7 May 2013 09:41:30 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Steven Rostedt , Luis Henriques Subject: [PATCH 061/118] tracing: Use stack of calling function for stack tracer Date: Tue, 7 May 2013 14:38:27 +0100 Message-Id: <1367933964-1564-62-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1367933964-1564-1-git-send-email-luis.henriques@canonical.com> References: <1367933964-1564-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: "Steven Rostedt (Red Hat)" commit 87889501d0adfae10e3b0f0e6f2d7536eed9ae84 upstream. Use the stack of stack_trace_call() instead of check_stack() as the test pointer for max stack size. It makes it a bit cleaner and a little more accurate. Adding stable, as a later fix depends on this patch. Signed-off-by: Steven Rostedt [ luis: adjust context ] Signed-off-by: Luis Henriques --- kernel/trace/trace_stack.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index aa4270a..6ee97e5 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -40,20 +40,21 @@ static DEFINE_MUTEX(stack_sysctl_mutex); int stack_tracer_enabled; static int last_stack_tracer_enabled; -static inline void check_stack(void) +static inline void +check_stack(unsigned long *stack) { unsigned long this_size, flags; unsigned long *p, *top, *start; int i; - this_size = ((unsigned long)&this_size) & (THREAD_SIZE-1); + this_size = ((unsigned long)stack) & (THREAD_SIZE-1); this_size = THREAD_SIZE - this_size; if (this_size <= max_stack_size) return; /* we do not handle interrupt stacks yet */ - if (!object_is_on_stack(&this_size)) + if (!object_is_on_stack(stack)) return; local_irq_save(flags); @@ -74,7 +75,7 @@ static inline void check_stack(void) * Now find where in the stack these are. */ i = 0; - start = &this_size; + start = stack; top = (unsigned long *) (((unsigned long)start & ~(THREAD_SIZE-1)) + THREAD_SIZE); @@ -113,6 +114,7 @@ static inline void check_stack(void) static void stack_trace_call(unsigned long ip, unsigned long parent_ip) { + unsigned long stack; int cpu; if (unlikely(!ftrace_enabled || stack_trace_disabled)) @@ -125,7 +127,7 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip) if (per_cpu(trace_active, cpu)++ != 0) goto out; - check_stack(); + check_stack(&stack); out: per_cpu(trace_active, cpu)--; -- 1.8.1.2