diff mbox

[v4,4/5] perf report: Show branch type statistics for stdio mode

Message ID 1491949266-6835-5-git-send-email-yao.jin@linux.intel.com (mailing list archive)
State Not Applicable
Headers show

Commit Message

Jin, Yao April 11, 2017, 10:21 p.m. UTC 
Show the branch type statistics at the end of perf report --stdio.

For example:
perf report --stdio

 JCC forward:  27.8%
JCC backward:   9.7%
    CROSS_4K:   0.0%
    CROSS_2M:  14.3%
         JCC:  37.6%
         JMP:   0.0%
     IND_JMP:   6.5%
        CALL:  26.6%
         RET:  29.3%
        IRET:   0.0%

The branch types are:
---------------------
 JCC forward: Conditional forward jump
JCC backward: Conditional backward jump
         JMP: Jump imm
     IND_JMP: Jump reg/mem
        CALL: Call imm
    IND_CALL: Call reg/mem
         RET: Ret
     SYSCALL: Syscall
      SYSRET: Syscall return
         IRQ: HW interrupt/trap/fault
         INT: SW interrupt
        IRET: Return from interrupt
  FAR_BRANCH: Others not generic branch type

CROSS_4K and CROSS_2M:
----------------------
They are the metrics checking for branches cross 4K or 2MB pages.
It's an approximate computing. We don't know if the area is 4K or
2MB, so always compute both.

To make the output simple, if a branch crosses 2M area, CROSS_4K
will not be incremented.

Comparing to previous version, the major changes are:

Add the computing of JCC forward/JCC backward and cross page checking
by using the from and to addresses.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
---
 tools/perf/builtin-report.c | 70 +++++++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/event.h     |  3 +-
 tools/perf/util/hist.c      |  5 +---
 tools/perf/util/util.c      | 59 ++++++++++++++++++++++++++++++++++++++
 tools/perf/util/util.h      | 17 +++++++++++
 5 files changed, 149 insertions(+), 5 deletions(-)

Comments

Jiri Olsa April 18, 2017, 6:53 p.m. UTC | #1 
On Wed, Apr 12, 2017 at 06:21:05AM +0800, Jin Yao wrote:

SNIP

> +const char *branch_type_name(int type)
> +{
> +	const char *branch_names[PERF_BR_MAX] = {
> +		"N/A",
> +		"JCC",
> +		"JMP",
> +		"IND_JMP",
> +		"CALL",
> +		"IND_CALL",
> +		"RET",
> +		"SYSCALL",
> +		"SYSRET",
> +		"IRQ",
> +		"INT",
> +		"IRET",
> +		"FAR_BRANCH",
> +	};
> +
> +	if ((type >= 0) && (type < PERF_BR_MAX))
> +		return branch_names[type];
> +
> +	return NULL;

looks like we should add util/branch.c with above functions
and merge it with util/parse-branch-options.c

we create new file even for less code ;-)

thanks,
jirka
Jiri Olsa April 18, 2017, 6:53 p.m. UTC | #2 
On Wed, Apr 12, 2017 at 06:21:05AM +0800, Jin Yao wrote:

SNIP

> +static int hist_iter__branch_callback(struct hist_entry_iter *iter,
> +				      struct addr_location *al __maybe_unused,
> +				      bool single __maybe_unused,
> +				      void *arg)
> +{
> +	struct hist_entry *he = iter->he;
> +	struct report *rep = arg;
> +	struct branch_info *bi;
> +
> +	if (sort__mode == SORT_MODE__BRANCH) {

is this check necessary? the hist_iter__branch_callback
was set based on this check

jirka
Jin, Yao April 19, 2017, 12:41 a.m. UTC | #3 
On 4/19/2017 2:53 AM, Jiri Olsa wrote:
> On Wed, Apr 12, 2017 at 06:21:05AM +0800, Jin Yao wrote:
>
> SNIP
>
>> +static int hist_iter__branch_callback(struct hist_entry_iter *iter,
>> +				      struct addr_location *al __maybe_unused,
>> +				      bool single __maybe_unused,
>> +				      void *arg)
>> +{
>> +	struct hist_entry *he = iter->he;
>> +	struct report *rep = arg;
>> +	struct branch_info *bi;
>> +
>> +	if (sort__mode == SORT_MODE__BRANCH) {
> is this check necessary? the hist_iter__branch_callback
> was set based on this check
>
> jirka

Let me double check.

Thanks
Jin Yao
Jin, Yao April 19, 2017, 12:53 a.m. UTC | #4 
On 4/19/2017 2:53 AM, Jiri Olsa wrote:
> On Wed, Apr 12, 2017 at 06:21:05AM +0800, Jin Yao wrote:
>
> SNIP
>
>> +const char *branch_type_name(int type)
>> +{
>> +	const char *branch_names[PERF_BR_MAX] = {
>> +		"N/A",
>> +		"JCC",
>> +		"JMP",
>> +		"IND_JMP",
>> +		"CALL",
>> +		"IND_CALL",
>> +		"RET",
>> +		"SYSCALL",
>> +		"SYSRET",
>> +		"IRQ",
>> +		"INT",
>> +		"IRET",
>> +		"FAR_BRANCH",
>> +	};
>> +
>> +	if ((type >= 0) && (type < PERF_BR_MAX))
>> +		return branch_names[type];
>> +
>> +	return NULL;
> looks like we should add util/branch.c with above functions
> and merge it with util/parse-branch-options.c
>
> we create new file even for less code ;-)
>
> thanks,
> jirka

Could we directly add branch_type_name() in util/parse-branch-options.c?

I just feel it's a bit waste of creating a new file for less code. :)

Thanks
Jin Yao
Jin, Yao April 19, 2017, 4:11 a.m. UTC | #5 
On 4/19/2017 8:53 AM, Jin, Yao wrote:
>
>
> On 4/19/2017 2:53 AM, Jiri Olsa wrote:
>> On Wed, Apr 12, 2017 at 06:21:05AM +0800, Jin Yao wrote:
>>
>> SNIP
>>
>>> +const char *branch_type_name(int type)
>>> +{
>>> +    const char *branch_names[PERF_BR_MAX] = {
>>> +        "N/A",
>>> +        "JCC",
>>> +        "JMP",
>>> +        "IND_JMP",
>>> +        "CALL",
>>> +        "IND_CALL",
>>> +        "RET",
>>> +        "SYSCALL",
>>> +        "SYSRET",
>>> +        "IRQ",
>>> +        "INT",
>>> +        "IRET",
>>> +        "FAR_BRANCH",
>>> +    };
>>> +
>>> +    if ((type >= 0) && (type < PERF_BR_MAX))
>>> +        return branch_names[type];
>>> +
>>> +    return NULL;
>> looks like we should add util/branch.c with above functions
>> and merge it with util/parse-branch-options.c
>>
>> we create new file even for less code ;-)
>>
>> thanks,
>> jirka
>
> Could we directly add branch_type_name() in util/parse-branch-options.c?
>
> I just feel it's a bit waste of creating a new file for less code. :)
>
> Thanks
> Jin Yao

After considering again, yes, creating util/branch.c should be better. I 
will do that.

Thanks
Jin Yao
diff mbox

Patch

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index c18158b..c2889eb 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -66,6 +66,7 @@  struct report {
 	u64			queue_size;
 	int			socket_filter;
 	DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
+	struct branch_type_stat	brtype_stat;
 };
 
 static int report__config(const char *var, const char *value, void *cb)
@@ -144,6 +145,24 @@  static int hist_iter__report_callback(struct hist_entry_iter *iter,
 	return err;
 }
 
+static int hist_iter__branch_callback(struct hist_entry_iter *iter,
+				      struct addr_location *al __maybe_unused,
+				      bool single __maybe_unused,
+				      void *arg)
+{
+	struct hist_entry *he = iter->he;
+	struct report *rep = arg;
+	struct branch_info *bi;
+
+	if (sort__mode == SORT_MODE__BRANCH) {
+		bi = he->branch_info;
+		branch_type_count(&rep->brtype_stat, &bi->flags,
+				  bi->from.addr, bi->to.addr);
+	}
+
+	return 0;
+}
+
 static int process_sample_event(struct perf_tool *tool,
 				union perf_event *event,
 				struct perf_sample *sample,
@@ -182,6 +201,8 @@  static int process_sample_event(struct perf_tool *tool,
 		 */
 		if (!sample->branch_stack)
 			goto out_put;
+
+		iter.add_entry_cb = hist_iter__branch_callback;
 		iter.ops = &hist_iter_branch;
 	} else if (rep->mem_mode) {
 		iter.ops = &hist_iter_mem;
@@ -369,6 +390,50 @@  static size_t hists__fprintf_nr_sample_events(struct hists *hists, struct report
 	return ret + fprintf(fp, "\n#\n");
 }
 
+static void branch_type_stat_display(FILE *fp, struct branch_type_stat *stat)
+{
+	u64 total = 0;
+	int i;
+
+	for (i = 0; i < PERF_BR_MAX; i++)
+		total += stat->counts[i];
+
+	if (total == 0)
+		return;
+
+	fprintf(fp, "\n#");
+	fprintf(fp, "\n# Branch Statistics:");
+	fprintf(fp, "\n#");
+
+	if (stat->jcc_fwd > 0)
+		fprintf(fp, "\n%12s: %5.1f%%",
+			"JCC forward",
+			100.0 * (double)stat->jcc_fwd / (double)total);
+
+	if (stat->jcc_bwd > 0)
+		fprintf(fp, "\n%12s: %5.1f%%",
+			"JCC backward",
+			100.0 * (double)stat->jcc_bwd / (double)total);
+
+	if (stat->cross_4k > 0)
+		fprintf(fp, "\n%12s: %5.1f%%",
+			"CROSS_4K",
+			100.0 * (double)stat->cross_4k / (double)total);
+
+	if (stat->cross_2m > 0)
+		fprintf(fp, "\n%12s: %5.1f%%",
+			"CROSS_2M",
+			100.0 * (double)stat->cross_2m / (double)total);
+
+	for (i = 0; i < PERF_BR_MAX; i++) {
+		if (stat->counts[i] > 0)
+			fprintf(fp, "\n%12s: %5.1f%%",
+				branch_type_name(i),
+				100.0 *
+				(double)stat->counts[i] / (double)total);
+	}
+}
+
 static int perf_evlist__tty_browse_hists(struct perf_evlist *evlist,
 					 struct report *rep,
 					 const char *help)
@@ -404,6 +469,9 @@  static int perf_evlist__tty_browse_hists(struct perf_evlist *evlist,
 		perf_read_values_destroy(&rep->show_threads_values);
 	}
 
+	if (sort__mode == SORT_MODE__BRANCH)
+		branch_type_stat_display(stdout, &rep->brtype_stat);
+
 	return 0;
 }
 
@@ -936,6 +1004,8 @@  int cmd_report(int argc, const char **argv)
 	if (has_br_stack && branch_call_mode)
 		symbol_conf.show_branchflag_count = true;
 
+	memset(&report.brtype_stat, 0, sizeof(struct branch_type_stat));
+
 	/*
 	 * Branch mode is a tristate:
 	 * -1 means default, so decide based on the file having branch data.
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index eb7a7b2..26b4c2e 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -142,7 +142,8 @@  struct branch_flags {
 	u64 in_tx:1;
 	u64 abort:1;
 	u64 cycles:16;
-	u64 reserved:44;
+	u64 type:4;
+	u64 reserved:40;
 };
 
 struct branch_entry {
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 61bf304..c8aee25 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -745,12 +745,9 @@  iter_prepare_branch_entry(struct hist_entry_iter *iter, struct addr_location *al
 }
 
 static int
-iter_add_single_branch_entry(struct hist_entry_iter *iter,
+iter_add_single_branch_entry(struct hist_entry_iter *iter __maybe_unused,
 			     struct addr_location *al __maybe_unused)
 {
-	/* to avoid calling callback function */
-	iter->he = NULL;
-
 	return 0;
 }
 
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index d8b45ce..a4b54a9 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -802,3 +802,62 @@  int unit_number__scnprintf(char *buf, size_t size, u64 n)
 
 	return scnprintf(buf, size, "%" PRIu64 "%c", n, unit[i]);
 }
+
+static bool cross_area(u64 addr1, u64 addr2, int size)
+{
+	u64 align1, align2;
+
+	align1 = addr1 & ~(size - 1);
+	align2 = addr2 & ~(size - 1);
+
+	return (align1 != align2) ? true : false;
+}
+
+#define AREA_4K		4096
+#define AREA_2M		(2 * 1024 * 1024)
+
+void branch_type_count(struct branch_type_stat *stat,
+		       struct branch_flags *flags,
+		       u64 from, u64 to)
+{
+	if ((flags->type == PERF_BR_NONE) || (from == 0))
+		return;
+
+	stat->counts[flags->type]++;
+
+	if (flags->type == PERF_BR_JCC) {
+		if (to > from)
+			stat->jcc_fwd++;
+		else
+			stat->jcc_bwd++;
+	}
+
+	if (cross_area(from, to, AREA_2M))
+		stat->cross_2m++;
+	else if (cross_area(from, to, AREA_4K))
+		stat->cross_4k++;
+}
+
+const char *branch_type_name(int type)
+{
+	const char *branch_names[PERF_BR_MAX] = {
+		"N/A",
+		"JCC",
+		"JMP",
+		"IND_JMP",
+		"CALL",
+		"IND_CALL",
+		"RET",
+		"SYSCALL",
+		"SYSRET",
+		"IRQ",
+		"INT",
+		"IRET",
+		"FAR_BRANCH",
+	};
+
+	if ((type >= 0) && (type < PERF_BR_MAX))
+		return branch_names[type];
+
+	return NULL;
+}
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 7cf5752..0a5bbcc 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -79,6 +79,7 @@ 
 #include <linux/bitops.h>
 #include <termios.h>
 #include "strlist.h"
+#include "../perf.h"
 
 extern const char *graph_line;
 extern const char *graph_dotted_line;
@@ -380,4 +381,20 @@  struct inline_node {
 struct inline_node *dso__parse_addr_inlines(struct dso *dso, u64 addr);
 void inline_node__delete(struct inline_node *node);
 
+struct branch_type_stat {
+	u64 counts[PERF_BR_MAX];
+	u64 jcc_fwd;
+	u64 jcc_bwd;
+	u64 cross_4k;
+	u64 cross_2m;
+};
+
+struct branch_flags;
+
+void branch_type_count(struct branch_type_stat *stat,
+		       struct branch_flags *flags,
+		       u64 from, u64 to);
+
+const char *branch_type_name(int type);
+
 #endif /* GIT_COMPAT_UTIL_H */