Hello.
I've been working on a new feature for perf annotate, which should be able to
annotate
instructions with total spent time (compared to percentage usage).
Let's consider following use-case. You want to compare two different compilers
on the same code base and let's assume 90% of wall-time is spent in a single
function.
Moreover, let's say that these compilers produce assembly of a totally
different size.
In such case, it's very useful to get an approximation of spent time on a bunch
of instructions,
which can be compared among other compilers. Otherwise, one has to somehow sum
percentages and compare
it to size of a function.
Mail contains my experimental patch.
However, last missing thing is that I need to calculate portion of cycles a
function
utilizes. May I ask you for help as perf annotate does not count these portions.
Thanks,
Martin
diff --git a/tools/perf/builtin-annotate.c b/tools/perf/builtin-annotate.c
index b57a027..cce19d6 100644
--- a/tools/perf/builtin-annotate.c
+++ b/tools/perf/builtin-annotate.c
@@ -326,6 +326,8 @@ int cmd_annotate(int argc, const char **argv, const char *prefix __maybe_unused)
"objdump binary to use for disassembly and annotations"),
OPT_BOOLEAN(0, "group", &symbol_conf.event_group,
"Show event group information together"),
+ OPT_BOOLEAN(0, "show-total-period", &symbol_conf.show_total_period,
+ "Show a column with the sum of periods"),
OPT_END()
};
int ret = hists__init();
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 5dfe913..dfd0c8c 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -484,6 +484,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
struct perf_session *session;
bool disabled = false, draining = false;
int fd;
+ unsigned long long t0, t1;
rec->progname = argv[0];
@@ -623,6 +624,8 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
if (!target__none(&opts->target) && !opts->initial_delay)
perf_evlist__enable(rec->evlist);
+ t0 = rdclock();
+
/*
* Let the child rip
*/
@@ -692,6 +695,9 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
goto out_child;
}
+ t1 = rdclock();
+ walltime_nsecs = t1 - t0;
+
if (!quiet)
fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index aa79fb8..0acdf4c 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -35,6 +35,8 @@ extern const char *input_name;
extern bool perf_host, perf_guest;
extern const char perf_version_string[];
+extern unsigned long long walltime_nsecs;
+
void pthread__unblock_sigwinch(void);
#include "util/target.h"
diff --git a/tools/perf/ui/browsers/annotate.c b/tools/perf/ui/browsers/annotate.c
index e5250eb..e7af8ec 100644
--- a/tools/perf/ui/browsers/annotate.c
+++ b/tools/perf/ui/browsers/annotate.c
@@ -113,7 +113,12 @@ static void annotate_browser__write(struct ui_browser *browser, void *entry, int
for (i = 0; i < ab->nr_events; i++) {
ui_browser__set_percent_color(browser, bdl->percent[i],
current_entry);
- slsmg_printf("%6.2f ", bdl->percent[i]);
+
+ if (symbol_conf.show_total_period)
+ slsmg_printf("%7.0f ", bdl->percent[i] *
+ walltime_nsecs / (100 * 1e6));
+ else
+ slsmg_printf("%7.2f ", bdl->percent[i]);
}
} else {
ui_browser__set_percent_color(browser, 0, current_entry);
diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 7f5bdfc..263e1bf 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -753,7 +753,12 @@ static int disasm_line__print(struct disasm_line *dl, struct symbol *sym, u64 st
for (i = 0; i < nr_percent; i++) {
percent = ppercents[i];
color = get_percent_color(percent);
- color_fprintf(stdout, color, " %7.2f", percent);
+
+ if (symbol_conf.show_total_period)
+ color_fprintf(stdout, color, " %7.0f",
+ percent * walltime_nsecs / (100 * 1e6));
+ else
+ color_fprintf(stdout, color, " %7.2f", percent);
}
printf(" : ");
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 3f0d809..a1d254b 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -47,6 +47,8 @@ struct perf_file_attr {
struct perf_file_section ids;
};
+unsigned long long walltime_nsecs;
+
void perf_header__set_feat(struct perf_header *header, int feat)
{
set_bit(feat, header->adds_features);
@@ -883,6 +885,14 @@ static int write_auxtrace(int fd, struct perf_header *h,
return err;
}
+static int write_total_wall_time(int fd, struct perf_header *h __maybe_unused,
+ struct perf_evlist *evlist __maybe_unused)
+{
+ do_write (fd, &walltime_nsecs, sizeof (walltime_nsecs));
+ return 0;
+}
+
+
static void print_hostname(struct perf_header *ph, int fd __maybe_unused,
FILE *fp)
{
@@ -1171,6 +1181,13 @@ static void print_auxtrace(struct perf_header *ph __maybe_unused,
fprintf(fp, "# contains AUX area data (e.g. instruction trace)\n");
}
+static void print_total_wall_time(struct perf_header *ph, int fd __maybe_unused,
+ FILE *fp)
+{
+ fprintf(fp, "# total wall-time: %.9f second\n",
+ ph->env.total_wall_time / 1e9);
+}
+
static void print_pmu_mappings(struct perf_header *ph, int fd __maybe_unused,
FILE *fp)
{
@@ -1857,6 +1874,23 @@ static int process_auxtrace(struct perf_file_section *section,
return err;
}
+static int process_total_wall_time(struct perf_file_section *section __maybe_unused,
+ struct perf_header *ph, int fd,
+ void *data __maybe_unused)
+{
+ ssize_t ret;
+
+ ret = readn(fd, &walltime_nsecs, sizeof(walltime_nsecs));
+ if (ret != sizeof(walltime_nsecs))
+ return -1;
+
+ if (ph->needs_swap)
+ walltime_nsecs = bswap_64(walltime_nsecs);
+
+ ph->env.total_wall_time = walltime_nsecs;
+ return 0;
+}
+
struct feature_ops {
int (*write)(int fd, struct perf_header *h, struct perf_evlist *evlist);
void (*print)(struct perf_header *h, int fd, FILE *fp);
@@ -1898,6 +1932,7 @@ static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
FEAT_OPP(HEADER_PMU_MAPPINGS, pmu_mappings),
FEAT_OPP(HEADER_GROUP_DESC, group_desc),
FEAT_OPP(HEADER_AUXTRACE, auxtrace),
+ FEAT_OPP(HEADER_TOTAL_WALLTIME, total_wall_time),
};
struct header_print_data {
diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index d4d5796..f47571a 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -31,6 +31,7 @@ enum {
HEADER_PMU_MAPPINGS,
HEADER_GROUP_DESC,
HEADER_AUXTRACE,
+ HEADER_TOTAL_WALLTIME,
HEADER_LAST_FEATURE,
HEADER_FEAT_BITS = 256,
};
@@ -88,6 +89,7 @@ struct perf_session_env {
char *sibling_threads;
char *numa_nodes;
char *pmu_mappings;
+ unsigned long long total_wall_time;
};
struct perf_header {
--
2.1.4
