Commit 993ac88d authored by Stephane Eranian's avatar Stephane Eranian Committed by Ingo Molnar
Browse files

perf report: Auto-detect branch stack sampling mode 



This patch enhances perf report to auto-detect when the
perf.data file contains samples with branch stacks. That way it
is not necessary to use the -b option.

To force branch view mode to off, simply use --no-branch-stack.

Signed-off-by: default avatarStephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: acme@redhat.com
Cc: asharma@fb.com
Cc: ravitillo@lbl.gov
Cc: vweaver1@eecs.utk.edu
Cc: khandual@linux.vnet.ibm.com
Cc: dsahern@gmail.com
Link: http://lkml.kernel.org/r/1331246868-19905-4-git-send-email-eranian@google.com


Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 330aa675

tools/perf/Documentation/perf-report.txt

+5 −2
Original line number Diff line number Diff line
@@ -157,8 +157,11 @@ OPTIONS 
--branch-stack::

	Use the addresses of sampled taken branches instead of the instruction

	address to build the histograms. To generate meaningful output, the

	perf.data file must have been obtained using perf record -b xxx where

	xxx is a branch filter option.

	perf.data file must have been obtained using perf record -b or

	perf record --branch-filter xxx where xxx is a branch filter option.

	perf report is able to auto-detect whether a perf.data file contains

	branch stacks and it will automatically switch to the branch view mode,

	unless --no-branch-stack is used.



SEE ALSO

--------

tools/perf/builtin-report.c

+34 −16
Original line number Diff line number Diff line
@@ -170,7 +170,7 @@ static int process_sample_event(struct perf_tool *tool, 
	if (rep->cpu_list && !test_bit(sample->cpu, rep->cpu_bitmap))

		return 0;



	if (sort__branch_mode) {

	if (sort__branch_mode == 1) {

		if (perf_report__add_branch_hist_entry(tool, &al, sample,

						       evsel, machine)) {

			pr_debug("problem adding lbr entry, skipping event\n");
@@ -239,7 +239,7 @@ static int perf_report__setup_sample_type(struct perf_report *rep) 
			}

	}



	if (sort__branch_mode) {

	if (sort__branch_mode == 1) {

		if (!(self->sample_type & PERF_SAMPLE_BRANCH_STACK)) {

			fprintf(stderr, "selected -b but no branch data."

					" Did you call perf record without"
@@ -306,7 +306,7 @@ static int __cmd_report(struct perf_report *rep) 
{

	int ret = -EINVAL;

	u64 nr_samples;

	struct perf_session *session;

	struct perf_session *session = rep->session;

	struct perf_evsel *pos;

	struct map *kernel_map;

	struct kmap *kernel_kmap;
@@ -314,13 +314,6 @@ static int __cmd_report(struct perf_report *rep) 


	signal(SIGINT, sig_handler);



	session = perf_session__new(rep->input_name, O_RDONLY,

				    rep->force, false, &rep->tool);

	if (session == NULL)

		return -ENOMEM;



	rep->session = session;



	if (rep->cpu_list) {

		ret = perf_session__cpu_bitmap(session, rep->cpu_list,

					       rep->cpu_bitmap);
@@ -487,9 +480,19 @@ setup: 
	return 0;

}



static int

parse_branch_mode(const struct option *opt __used, const char *str __used, int unset)

{

	sort__branch_mode = !unset;

	return 0;

}



int cmd_report(int argc, const char **argv, const char *prefix __used)

{

	struct perf_session *session;

	struct stat st;

	bool has_br_stack = false;

	int ret = -1;

	char callchain_default_opt[] = "fractal,0.5,callee";

	const char * const report_usage[] = {

		"perf report [<options>]",
@@ -578,8 +581,8 @@ int cmd_report(int argc, const char **argv, const char *prefix __used) 
		   "Specify disassembler style (e.g. -M intel for intel syntax)"),

	OPT_BOOLEAN(0, "show-total-period", &symbol_conf.show_total_period,

		    "Show a column with the sum of periods"),

	OPT_BOOLEAN('b', "branch-stack", &sort__branch_mode,

		    "use branch records for histogram filling"),

	OPT_CALLBACK_NOOPT('b', "branch-stack", &sort__branch_mode, "",

		    "use branch records for histogram filling", parse_branch_mode),

	OPT_END()

	};
@@ -599,8 +602,20 @@ int cmd_report(int argc, const char **argv, const char *prefix __used) 
		else

			report.input_name = "perf.data";

	}

	session = perf_session__new(report.input_name, O_RDONLY,

				    report.force, false, &report.tool);

	if (session == NULL)

		return -ENOMEM;



	report.session = session;



	has_br_stack = perf_header__has_feat(&session->header,

					     HEADER_BRANCH_STACK);



	if (sort__branch_mode) {

	if (sort__branch_mode == -1 && has_br_stack)

		sort__branch_mode = 1;



	if (sort__branch_mode == 1) {

		if (use_browser)

			fprintf(stderr, "Warning: TUI interface not supported"

					" in branch mode\n");
@@ -657,13 +672,13 @@ int cmd_report(int argc, const char **argv, const char *prefix __used) 
	}



	if (symbol__init() < 0)

		return -1;

		goto error;



	setup_sorting(report_usage, options);



	if (parent_pattern != default_parent_pattern) {

		if (sort_dimension__add("parent") < 0)

			return -1;

			goto error;



		/*

		 * Only show the parent fields if we explicitly
@@ -685,5 +700,8 @@ int cmd_report(int argc, const char **argv, const char *prefix __used) 
	sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", stdout);

	sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", stdout);



	return __cmd_report(&report);

	ret = __cmd_report(&report);

error:

	perf_session__delete(session);

	return ret;

}

tools/perf/util/sort.c

+1 −1
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ const char default_sort_order[] = "comm,dso,symbol"; 
const char	*sort_order = default_sort_order;

int		sort__need_collapse = 0;

int		sort__has_parent = 0;

bool		sort__branch_mode;

int		sort__branch_mode = -1; /* -1 = means not set */



enum sort_type	sort__first_dimension;

tools/perf/util/sort.h

+1 −1
Original line number Diff line number Diff line
@@ -31,7 +31,7 @@ extern const char *parent_pattern; 
extern const char default_sort_order[];

extern int sort__need_collapse;

extern int sort__has_parent;

extern bool sort__branch_mode;

extern int sort__branch_mode;

extern char *field_sep;

extern struct sort_entry sort_comm;

extern struct sort_entry sort_dso;

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