diff options
| author |   Frederic Weisbecker <fweisbec@gmail.com> | 2008-12-06 03:43:41 +0100 |
|---|---|---|
| committer |   Ingo Molnar <mingo@elte.hu> | 2008-12-08 15:11:45 +0100 |
| commit | 380c4b1411ccd6885f92b2c8ceb08433a720f44e (patch) | |
| tree | f3b571e1caff2de3e6b4cace87c2b1ec332667d7 /arch/x86/kernel/ftrace.c | |
| parent | tracing/function-graph-tracer: turn tracing_selftest_running into an int (diff) | |
| download | linux-dev-380c4b1411ccd6885f92b2c8ceb08433a720f44e.tar.xz linux-dev-380c4b1411ccd6885f92b2c8ceb08433a720f44e.zip | |
tracing/function-graph-tracer: append the tracing_graph_flag
Impact: Provide a way to pause the function graph tracer
As suggested by Steven Rostedt, the previous patch that prevented from
spinlock function tracing shouldn't use the raw_spinlock to fix it.
It's much better to follow lockdep with normal spinlock, so this patch
adds a new flag for each task to make the function graph tracer able
to be paused. We also can send an ftrace_printk whithout worrying of
the irrelevant traced spinlock during insertion.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/ftrace.c')
| -rw-r--r-- | arch/x86/kernel/ftrace.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index f98c4076a170..1b43086b097a 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -476,7 +476,10 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr) &return_to_handler; /* Nmi's are currently unsupported */ - if (atomic_read(&in_nmi)) + if (unlikely(atomic_read(&in_nmi))) + return; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) return; /* |