diff options
| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2018-04-04 14:50:15 -0400 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2018-04-06 08:56:52 -0400 |
| commit | f7a1570da91558fb85b61e53243fe3fa79e2bbae (patch) | |
| tree | 36602d82229665a0e1375017a78353d21154610f | |
| parent | 927e56db6253225166d521cee3772624347b5cd5 (diff) | |
tracing: Hide global trace clock from lockdep
Function tracing can trace in NMIs and such. If the TSC is determined
to be unstable, the tracing clock will switch to the global clock on
boot up, unless "trace_clock" is specified on the kernel command line.
The global clock disables interrupts to access sched_clock_cpu(), and in
doing so can be done within lockdep internals (because of function
tracing and NMIs). This can trigger false lockdep splats.
The trace_clock_global() is special, best not to trace the irq logic
within it.
Link: http://lkml.kernel.org/r/20180404145015.77bde42d@gandalf.local.home
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| -rw-r--r-- | kernel/trace/trace_clock.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c index 5fdc779f411d..d8a188e0418a 100644 --- a/kernel/trace/trace_clock.c +++ b/kernel/trace/trace_clock.c @@ -96,7 +96,7 @@ u64 notrace trace_clock_global(void) int this_cpu; u64 now; - local_irq_save(flags); + raw_local_irq_save(flags); this_cpu = raw_smp_processor_id(); now = sched_clock_cpu(this_cpu); @@ -122,7 +122,7 @@ u64 notrace trace_clock_global(void) arch_spin_unlock(&trace_clock_struct.lock); out: - local_irq_restore(flags); + raw_local_irq_restore(flags); return now; } |