perf/UAPI: Clearly mark __PERF_SAMPLE_CALLCHAIN_EARLY as internal use

Vince noted that commit:

  6cbc304f2f36 ("perf/x86/intel: Fix unwind errors from PEBS entries (mk-II)")

'leaked' __PERF_SAMPLE_CALLCHAIN_EARLY into the UAPI namespace. And
while sys_perf_event_open() will error out if you try to use it, it is
exposed.

Clearly mark it for internal use only to avoid any confusion.

Requested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index eeb787b1c53c72771c8d684154b7a87dc029a45b..f35eb72739c09e3ad0bd22e279fa4a33119c15f6 100644 (file)
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -144,7 +144,7 @@ enum perf_event_sample_format {
 
        PERF_SAMPLE_MAX = 1U << 20,             /* non-ABI */
 
-       __PERF_SAMPLE_CALLCHAIN_EARLY           = 1ULL << 63,
+       __PERF_SAMPLE_CALLCHAIN_EARLY           = 1ULL << 63, /* non-ABI; internal use */
 };
 
 /*