perf: Add PERF_SAMPLE_BRANCH_CALL

This change “perf: Add PERF_SAMPLE_BRANCH_CALL” in Linux kernel is authored by Stephane Eranian <eranian [at] google.com> on Tue Oct 13 09:09:08 2015 +0200.

perf: Add PERF_SAMPLE_BRANCH_CALL

Add a new branch sample type to cover only call branches (function calls).
The current ANY_CALL included direct, indirect calls and far jumps.

We want to be able to differentiate indirect from direct calls. Therefore
we introduce PERF_SAMPLE_BRANCH_CALL. The implementation is up to each
architecture.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: khandual@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1444720151-10275-2-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

This Linux change may have been applied to various maintained Linux releases and you can find Linux releases including commit c229bf9.

There are 2 lines of Linux source code added/deleted in this change. Code changes to Linux kernel are as follows.

 include/uapi/linux/perf_event.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index 6c72e72..6512213 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -168,6 +168,7 @@ enum perf_branch_sample_type_shift {
 
 	PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT	= 11, /* call/ret stack */
 	PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT	= 12, /* indirect jumps */
+	PERF_SAMPLE_BRANCH_CALL_SHIFT		= 13, /* direct call */
 
 	PERF_SAMPLE_BRANCH_MAX_SHIFT		/* non-ABI */
 };
@@ -188,6 +189,7 @@ enum perf_branch_sample_type {
 
 	PERF_SAMPLE_BRANCH_CALL_STACK	= 1U << PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT,
 	PERF_SAMPLE_BRANCH_IND_JUMP	= 1U << PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT,
+	PERF_SAMPLE_BRANCH_CALL		= 1U << PERF_SAMPLE_BRANCH_CALL_SHIFT,
 
 	PERF_SAMPLE_BRANCH_MAX		= 1U << PERF_SAMPLE_BRANCH_MAX_SHIFT,
 };

The commit for this change in Linux stable tree is c229bf9 (patch).

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