lkml.org 
[lkml]   [2008]   [Dec]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp()

* Frederic Weisbecker <fweisbec@gmail.com> wrote:

> Impact: prevent a trace recursion
>
> After some tests with function graph tracer under x86-32, I saw some recursions
> caused by ring_buffer_time_stamp() that calls preempt_enable_no_notrace() which
> calls preempt_schedule() which is traced itself.
>
> This patch re-enables preemption without rescheduling.
>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
> ---
> kernel/trace/ring_buffer.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)

applied to tip/tracing/ftrace, thanks Frederic!

Does this explain+fix the weird crashes/reboots you were seeing?

Ingo


\
 
 \ /
  Last update: 2008-12-16 22:23    [W:0.250 / U:0.568 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site