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| author | Li Zefan <lizf@cn.fujitsu.com> | 2009-06-26 16:55:51 +0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-06-26 20:48:39 +0200 |
| commit | a32c7765e2796395aec49f699bd25c407155e9c5 (patch) | |
| tree | 6d46f223a177ada92c6f47c36ba2e51cd6041037 /kernel/trace | |
| parent | 0296e4254f3318e0dcad9706fa1daf8e5addc1e9 (diff) | |
| download | linux-a32c7765e2796395aec49f699bd25c407155e9c5.tar.gz linux-a32c7765e2796395aec49f699bd25c407155e9c5.tar.bz2 linux-a32c7765e2796395aec49f699bd25c407155e9c5.zip | |
tracing: Fix stack tracer sysctl handling
This made my machine completely frozen:
# echo 1 > /proc/sys/kernel/stack_tracer_enabled
# echo 2 > /proc/sys/kernel/stack_tracer_enabled
The cause is register_ftrace_function() was called twice.
Also fix ftrace_enabled sysctl, though seems nothing bad happened
as I tested it.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A448D17.9010305@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/ftrace.c | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_stack.c | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f3716bf04df6..bce9e01a29c8 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3160,10 +3160,10 @@ ftrace_enable_sysctl(struct ctl_table *table, int write, ret = proc_dointvec(table, write, file, buffer, lenp, ppos); - if (ret || !write || (last_ftrace_enabled == ftrace_enabled)) + if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) goto out; - last_ftrace_enabled = ftrace_enabled; + last_ftrace_enabled = !!ftrace_enabled; if (ftrace_enabled) { diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index 2d7aebd71dbd..e644af910124 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -326,10 +326,10 @@ stack_trace_sysctl(struct ctl_table *table, int write, ret = proc_dointvec(table, write, file, buffer, lenp, ppos); if (ret || !write || - (last_stack_tracer_enabled == stack_tracer_enabled)) + (last_stack_tracer_enabled == !!stack_tracer_enabled)) goto out; - last_stack_tracer_enabled = stack_tracer_enabled; + last_stack_tracer_enabled = !!stack_tracer_enabled; if (stack_tracer_enabled) register_ftrace_function(&trace_ops); |