Pull perf fixes from Ingo Molnar:
"Two fixes:
- Fix 'NMI handler took too long to run' false positives
[ Genuine NMI overhead speedups will come for v3.13, this commit
only fixes a measurement bug ]
- Fix perf ring-buffer missed barrier causing (rare) ring-buffer data
corruption on ppc64"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Fix NMI measurements
perf: Fix perf ring buffer memory ordering