[PATCH 2/4] perf, tools: Add --branch-call-stack option to report

Andi Kleen
2014-01-10T12:32:23Z

From: Andi Kleen <ak@linux.intel.com>

Add a --branch-call-stack option toperf report that changes all
the settings necessary for using the branches in callstacks.

This is just a short cut to make this nicer to use.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
tools/perf/Documentation/perf-report.txt | 5 +++++
tools/perf/builtin-report.c | 25 ++++++++++++++++++++++---
2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index 10a2798..77ec0b9 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -223,6 +223,11 @@ OPTIONS
branch stacks and it will automatically switch to the branch view mode,
unless --no-branch-stack is used.

+--branch-call-stack::
+ Add the addresses of sampled taken branches to the callstack.
+ This allows to examine the path the program took to each sample.
+ The data collection must have used -b or -j.
+
--objdump=<path>::
Path to objdump binary.

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index c2e6e43..c39d1ac 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -763,6 +763,16 @@ parse_branch_mode(const struct option *opt __maybe_unused,
}

static int
+parse_branch_call_mode(const struct option *opt __maybe_unused,
+ const char *str __maybe_unused, int unset)
+{
+ int *branch_mode = opt->value;
+
+ *branch_mode = !unset;
+ return 0;
+}
+
+static int
parse_percent_limit(const struct option *opt, const char *str,
int unset __maybe_unused)
{
@@ -777,7 +787,7 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
struct perf_session *session;
struct stat st;
bool has_br_stack = false;
- int branch_mode = -1;
+ int branch_mode = -1, branch_call_mode = -1;
int ret = -1;
char callchain_default_opt[] = "fractal,0.5,callee";
const char * const report_usage[] = {
@@ -883,7 +893,10 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
OPT_BOOLEAN(0, "group", &symbol_conf.event_group,
"Show event group information together"),
OPT_CALLBACK_NOOPT('b', "branch-stack", &branch_mode, "",
- "use branch records for histogram filling", parse_branch_mode),
+ "use branch records for per branch histogram filling", parse_branch_mode),
+ OPT_CALLBACK_NOOPT(0, "branch-call-stack", &branch_call_mode, "",
+ "add last branch records to call stack",
+ parse_branch_call_mode),
OPT_STRING(0, "objdump", &objdump_path, "path",
"objdump binary to use for disassembly and annotations"),
OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
@@ -931,8 +944,14 @@ repeat:
has_br_stack = perf_header__has_feat(&session->header,
HEADER_BRANCH_STACK);

- if (branch_mode == -1 && has_br_stack)
+ if (branch_mode == -1 && has_br_stack && branch_call_mode == -1)
sort__mode = SORT_MODE__BRANCH;
+ if (branch_call_mode != -1) {
+ callchain_param.branch_callstack = 1;
+ callchain_param.key = CCKEY_ADDRESS;
+ symbol_conf.use_callchain = true;
+ callchain_register_param(&callchain_param);
+ }

/* sort__mode could be NORMAL if --no-branch-stack */
if (sort__mode == SORT_MODE__BRANCH) {
--
1.8.3.1