On Tue, Dec 10, 2013 at 01:18:20PM -0800, Linus Torvalds wrote: > On Tue, Dec 10, 2013 at 1:06 PM, Darren Hart <dvh...@linux.intel.com> wrote: > > > > . Knowing exactly what syscall was made would > > be very useful, but I don't know if that information is even available > > anymore. > > Well, the loop should be visible in the profile, since it's still active. > > So doing something like > > perf record -e cycles:pp -g -a sleep 60 > > to get a good profile for a minute, and then looking at the > instruction-level profiles in futex_requeue() should be possible. > > Of course, inlining etc often makes those rather hard to see, and the > bulk of the profile is clearly all about the lock debugging overhead, > but if the loop is in futex_requeue() then that *should* be visible in > the profile, even if it may not be anywhere near the top.. > > Dave?
http://www.codemonkey.org.uk/junk/perf.data.xz Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
