Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, amd: Use kmalloc_node(,__GFP_ZERO) for northbridge structure allocation
  perf_events: Fix time tracking in samples
  perf trace: update usage
  perf trace: update Documentation with new perf trace variants
  perf trace: live-mode command-line cleanup
  perf trace record: handle commands correctly
  perf record: make the record options available outside perf record
  perf trace scripting: remove system-wide param from shell scripts
  perf trace scripting: fix some small memory leaks and missing error checks
  perf: Fix usages of profile_cpu in builtin-top.c to use cpu_list
  perf, ui: Eliminate stack-smashing protection compiler complaint

1 files changed, 10 insertions, 0 deletions

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 057bf22a832..40150f34598 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -747,6 +747,16 @@ struct perf_event {
 	u64				tstamp_running;
 	u64				tstamp_stopped;
 
+	/*
+	 * timestamp shadows the actual context timing but it can
+	 * be safely used in NMI interrupt context. It reflects the
+	 * context time as it was when the event was last scheduled in.
+	 *
+	 * ctx_time already accounts for ctx->timestamp. Therefore to
+	 * compute ctx_time for a sample, simply add perf_clock().
+	 */
+	u64				shadow_ctx_time;
+
 	struct perf_event_attr		attr;
 	struct hw_perf_event		hw;