Messages in this thread | | | Date | Wed, 4 Feb 2009 18:36:43 +0300 | From | Anton Vorontsov <> | Subject | Re: [PATCH 3/3] tracing: Tracers that use CALLER_ADDR macros should select FRAME_POINTER |
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On Wed, Feb 04, 2009 at 04:26:15PM +0100, Frédéric Weisbecker wrote: [...] > > @@ -136,6 +138,7 @@ config SCHED_TRACER > > select TRACING > > select CONTEXT_SWITCH_TRACER > > select TRACER_MAX_TRACE > > + select FRAME_POINTER > > help > > This tracer tracks the latency of the highest priority task > > to be scheduled in, starting from the point it has woken up. > > -- > > > Looks right. > > BTW, how behaves builtin_return_address in case of !FRAME_POINTERS ? > I guess it would only work with the first caller builtin_return_address(0)
It depends on the architecture. On PowerPC we always have frame pointers, thus __builtin_return_address(1..) will always work. On x86 it won't work that way.
Thanks,
-- Anton Vorontsov email: cbouatmailru@gmail.com irc://irc.freenode.net/bd2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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