diff options
author | Frederic Weisbecker <fweisbec@gmail.com> | 2008-11-23 06:22:56 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-11-23 09:17:26 +0100 |
commit | f201ae2356c74bcae130b2177b3dca903ea98071 (patch) | |
tree | c4b1b43fbe0a4594cb86749b2e7098fe15eb86ba /kernel/sched.c | |
parent | a0a70c735ef714fe1b6777b571630c3d50c7b008 (diff) | |
download | op-kernel-dev-f201ae2356c74bcae130b2177b3dca903ea98071.zip op-kernel-dev-f201ae2356c74bcae130b2177b3dca903ea98071.tar.gz |
tracing/function-return-tracer: store return stack into task_struct and allocate it dynamically
Impact: use deeper function tracing depth safely
Some tests showed that function return tracing needed a more deeper depth
of function calls. But it could be unsafe to store these return addresses
to the stack.
So these arrays will now be allocated dynamically into task_struct of current
only when the tracer is activated.
Typical scheme when tracer is activated:
- allocate a return stack for each task in global list.
- fork: allocate the return stack for the newly created task
- exit: free return stack of current
- idle init: same as fork
I chose a default depth of 50. I don't have overruns anymore.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched.c')
-rw-r--r-- | kernel/sched.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 4de5610..fb17205 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -5901,6 +5901,9 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) * The idle tasks have their own, simple scheduling class: */ idle->sched_class = &idle_sched_class; +#ifdef CONFIG_FUNCTION_RET_TRACER + ftrace_retfunc_init_task(idle); +#endif } /* |