[tip:perf/core] perf/x86: Add support for PERF_SAMPLE_BRANCH_CALL

tip-bot for Stephane Eranian
2015-10-20T09:36:59Z

Commit-ID: d892819faa6860d469aae71d70c336b391c25505
Gitweb: http://git.kernel.org/tip/d892819faa6860d469aae71d70c336b391c25505
Author: Stephane Eranian <eranian@google.com>
AuthorDate: Tue, 13 Oct 2015 09:09:09 +0200
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 20 Oct 2015 10:30:53 +0200

perf/x86: Add support for PERF_SAMPLE_BRANCH_CALL

This patch enables the suport for the PERF_SAMPLE_BRANCH_CALL
for Intel x86 processors. When the processor support LBR filtering
this the selection is done in hardware. Otherwise, the filter is
applied by software. Note that we chose to include zero length calls
because they also represent calls.

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/1444720151-10275-3-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/kernel/cpu/perf_event_intel_lbr.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c
index ad0b8b0..bfd0b71 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c
@@ -555,6 +555,8 @@ static int intel_pmu_setup_sw_lbr_filter(struct perf_event *event)
if (br_type & PERF_SAMPLE_BRANCH_IND_JUMP)
mask |= X86_BR_IND_JMP;

+ if (br_type & PERF_SAMPLE_BRANCH_CALL)
+ mask |= X86_BR_CALL | X86_BR_ZERO_CALL;
/*
* stash actual user request into reg, it may
* be used by fixup code for some CPU
@@ -890,6 +892,7 @@ static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = {
[PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL,
[PERF_SAMPLE_BRANCH_COND_SHIFT] = LBR_JCC,
[PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP,
+ [PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_REL_CALL,
};

static const int hsw_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = {
@@ -905,6 +908,7 @@ static const int hsw_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX_SHIFT] = {
[PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT] = LBR_REL_CALL | LBR_IND_CALL
| LBR_RETURN | LBR_CALL_STACK,
[PERF_SAMPLE_BRANCH_IND_JUMP_SHIFT] = LBR_IND_JMP,
+ [PERF_SAMPLE_BRANCH_CALL_SHIFT] = LBR_REL_CALL,
};

/* core */