sched_clock() should be fast, scalable and not use any lock. As a resuly it should be safely called from NMIs.
Now just in case there might be some implementation details proper to some archs that make sched_clock() not reliable or not safe in NMIs, lets provide a way through Kconfig for archs to testify about that support. Signed-off-by: Frederic Weisbecker <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: John Stultz <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Don Zickus <[email protected]> --- arch/Kconfig | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 1feb169..52ad235 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -393,6 +393,11 @@ config HAVE_UNDERSCORE_SYMBOL_PREFIX Some architectures generate an _ in front of C symbols; things like module loading and assembly files need to know about this. +config HAVE_SCHED_CLOCK_NMI + bool + help + Architecture's sched_clock() implementation is safely callable from NMIs. + # # ABI hall of shame # -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
