diff options
| author | Steven Rostedt <rostedt@goodmis.org> | 2012-06-04 16:27:54 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-07-16 09:03:21 -0700 |
| commit | 3f8d5752c3926dab96e00bfb5d0c8e2f015a975e (patch) | |
| tree | 32ca440fda746c596e5099eefe6960904e984c64 /arch | |
| parent | 9fe9217b874769f0b42bc4f8de4fc3df785e9ef3 (diff) | |
powerpc/ftrace: Do not trace restore_interrupts()
commit 2d773aa4810d4a612d1c879faacc38594cc3f841 upstream.
As I was adding code that affects all archs, I started testing function
tracer against PPC64 and found that it currently locks up with 3.4
kernel. I figured it was due to tracing a function that shouldn't be, so
I went through the following process to bisect to find the culprit:
cat /debug/tracing/available_filter_functions > t
num=`wc -l t`
sed -ne "1,${num}p" t > t1
let num=num+1
sed -ne "${num},$p" t > t2
cat t1 > /debug/tracing/set_ftrace_filter
echo function /debug/tracing/current_tracer
<failed? bisect t1, if not bisect t2>
It finally came down to this function: restore_interrupts()
I'm not sure why this locks up the system. It just seems to prevent
scheduling from occurring. Interrupts seem to still work, as I can ping
the box. But all user processes freeze.
When restore_interrupts() is not traced, function tracing works fine.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/irq.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 641da9e868c..64eec59193f 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -277,7 +277,7 @@ EXPORT_SYMBOL(arch_local_irq_restore); * NOTE: This is called with interrupts hard disabled but not marked * as such in paca->irq_happened, so we need to resync this. */ -void restore_interrupts(void) +void notrace restore_interrupts(void) { if (irqs_disabled()) { local_paca->irq_happened |= PACA_IRQ_HARD_DIS; |