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| 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 | |
| parent | 8e1b82e0866befaa0b2920be296c6e4c3fc7f422 (diff) | |
| download | op-kernel-dev-380c4b1411ccd6885f92b2c8ceb08433a720f44e.zip op-kernel-dev-380c4b1411ccd6885f92b2c8ceb08433a720f44e.tar.gz | |
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')
| -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 f98c407..1b43086 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; /* |
