From 29a679754b1a2581ee456eada6c2de7ce95068bb Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Thu, 14 May 2009 23:19:09 -0400
Subject: [PATCH] x86/stacktrace: return 0 instead of -1 for stack ops
If we return -1 in the ops->stack for the stacktrace saving, we end up
breaking out of the loop if the stack we are tracing is in the exception
stack. This causes traces like:
<idle>-0 [002] 34263.745825: raise_softirq_irqoff <-__blk_complete_request
<idle>-0 [002] 34263.745826:
<= 0
<= 0
<= 0
<= 0
<= 0
<= 0
<= 0
By returning "0" instead, the irq stack is saved as well, and we see:
<idle>-0 [003] 883.280992: raise_softirq_irqoff <-__hrtimer_star
t_range_ns
<idle>-0 [003] 883.280992:
<= hrtimer_start_range_ns
<= tick_nohz_restart_sched_tick
<= cpu_idle
<= start_secondary
<=
<= 0
<= 0
[ Impact: record stacks from interrupts ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
arch/x86/kernel/stacktrace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c
index f7bddc2e37d1..4aaf7e48394f 100644
--- a/arch/x86/kernel/stacktrace.c
+++ b/arch/x86/kernel/stacktrace.c
@@ -20,7 +20,7 @@ save_stack_warning_symbol(void *data, char *msg, unsigned long symbol)
static int save_stack_stack(void *data, char *name)
{
- return -1;
+ return 0;
}
static void save_stack_address(void *data, unsigned long addr, int reliable)