[PATCH 3/3] PERF(userspace): Adjust perf timechart to the new power events

Thomas Renninger
2010-11-11T18:03:20Z

Recent changes:
- Adjust state/cpuid to u32 as done in the kernel

The transition was rather smooth, only part I had to fiddle
some time was the check whether a tracepoint/event is
supported by the running kernel.

builtin-timechart must only pass -e power:xy events which
are supported by the running kernel.
For this I added the tiny helper function:
int is_valid_tracepoint(const char *event_string)
to parse-events.[hc]
which could be more generic as an interface and support
hardware/software/... events, not only tracepoints, but someone
else could extend that if needed...

Signed-off-by: Thomas Renninger <trenn@suse.de>
CC: Jean Pihet <jean.pihet@newoldbits.com>
CC: Arjan van de Ven <arjan@linux.intel.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: linux-kernel@vger.kernel.org
---
tools/perf/builtin-timechart.c | 91 ++++++++++++++++++++++++++++++++-------
tools/perf/util/parse-events.c | 41 ++++++++++++++++++
tools/perf/util/parse-events.h | 1 +
3 files changed, 116 insertions(+), 17 deletions(-)

diff --git a/tools/perf/builtin-timechart.c b/tools/perf/builtin-timechart.c
index 9bcc38f..299e488 100644
--- a/tools/perf/builtin-timechart.c
+++ b/tools/perf/builtin-timechart.c
@@ -32,6 +32,10 @@
#include "util/session.h"
#include "util/svghelper.h"

+#define SUPPORT_OLD_POWER_EVENTS 1
+#define PWR_EVENT_EXIT -1
+
+
static char const *input_name = "perf.data";
static char const *output_name = "output.svg";

@@ -298,12 +302,21 @@ struct trace_entry {
int lock_depth;
};

-struct power_entry {
+#if defined(SUPPORT_OLD_POWER_EVENTS)
+static int use_old_power_events;
+struct power_entry_old {
struct trace_entry te;
u64 type;
u64 value;
u64 cpu_id;
};
+#endif
+
+struct power_processor_entry {
+ struct trace_entry te;
+ u32 state;
+ u32 cpu_id;
+};

#define TASK_COMM_LEN 16
struct wakeup_entry {
@@ -489,29 +502,48 @@ static int process_sample_event(event_t *event, struct perf_session *session)
te = (void *)data.raw_data;
if (session->sample_type & PERF_SAMPLE_RAW && data.raw_size > 0) {
char *event_str;
- struct power_entry *pe;
-
- pe = (void *)te;
+#if defined(SUPPORT_OLD_POWER_EVENTS)
+ struct power_entry_old *peo;
+ peo = (void *)te;
+#endif

event_str = perf_header__find_event(te->type);

if (!event_str)
return 0;

- if (strcmp(event_str, "power:power_start") == 0)
- c_state_start(pe->cpu_id, data.time, pe->value);
-
- if (strcmp(event_str, "power:power_end") == 0)
- c_state_end(pe->cpu_id, data.time);
+ if (strcmp(event_str, "power:cpu_idle") == 0) {
+ struct power_processor_entry *ppe = (void *)te;
+ if (ppe->state == (u32)PWR_EVENT_EXIT)
+ c_state_end(ppe->cpu_id, data.time);
+ else
+ c_state_start(ppe->cpu_id, data.time,
+ ppe->state);
+ }

- if (strcmp(event_str, "power:power_frequency") == 0)
- p_state_change(pe->cpu_id, data.time, pe->value);
+ else if (strcmp(event_str, "power:cpu_frequency") == 0) {
+ struct power_processor_entry *ppe = (void *)te;
+ p_state_change(ppe->cpu_id, data.time, ppe->state);
+ }

- if (strcmp(event_str, "sched:sched_wakeup") == 0)
+ else if (strcmp(event_str, "sched:sched_wakeup") == 0)
sched_wakeup(data.cpu, data.time, data.pid, te);

- if (strcmp(event_str, "sched:sched_switch") == 0)
+ else if (strcmp(event_str, "sched:sched_switch") == 0)
sched_switch(data.cpu, data.time, te);
+
+#if defined(SUPPORT_OLD_POWER_EVENTS)
+ if (use_old_power_events) {
+ if (strcmp(event_str, "power:power_start") == 0)
+ c_state_start(peo->cpu_id, data.time, peo->value);
+
+ else if (strcmp(event_str, "power:power_end") == 0)
+ c_state_end(data.cpu, data.time);
+
+ else if (strcmp(event_str, "power:power_frequency") == 0)
+ p_state_change(peo->cpu_id, data.time, peo->value);
+ }
+#endif
}
return 0;
}
@@ -968,7 +1000,8 @@ static const char * const timechart_usage[] = {
NULL
};

-static const char *record_args[] = {
+#if defined(SUPPORT_OLD_POWER_EVENTS)
+static const char *record_old_args[] = {
"record",
"-a",
"-R",
@@ -980,16 +1013,40 @@ static const char *record_args[] = {
"-e", "sched:sched_wakeup",
"-e", "sched:sched_switch",
};
+#endif
+
+static const char *record_new_args[] = {
+ "record",
+ "-a",
+ "-R",
+ "-f",
+ "-c", "1",
+ "-e", "power:cpu_frequency",
+ "-e", "power:cpu_idle",
+ "-e", "sched:sched_wakeup",
+ "-e", "sched:sched_switch",
+};

static int __cmd_record(int argc, const char **argv)
{
unsigned int rec_argc, i, j;
const char **rec_argv;
-
- rec_argc = ARRAY_SIZE(record_args) + argc - 1;
+ const char **record_args = record_new_args;
+ unsigned int record_elems = ARRAY_SIZE(record_new_args);
+
+#if defined(SUPPORT_OLD_POWER_EVENTS)
+ if (!is_valid_tracepoint("power:cpu_idle") &&
+ is_valid_tracepoint("power:power_start")) {
+ use_old_power_events = 1;
+ record_args = record_old_args;
+ record_elems = ARRAY_SIZE(record_old_args);
+ }
+#endif
+
+ rec_argc = record_elems + argc - 1;
rec_argv = calloc(rec_argc + 1, sizeof(char *));

- for (i = 0; i < ARRAY_SIZE(record_args); i++)
+ for (i = 0; i < record_elems; i++)
rec_argv[i] = strdup(record_args[i]);

for (j = 1; j < (unsigned int)argc; j++, i++)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 4af5bd5..35e3dea 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -906,6 +906,47 @@ static void print_tracepoint_events(void)
}

/*
+ * Check whether event is in <debugfs_mount_point>/tracing/events
+ */
+
+int is_valid_tracepoint(const char *event_string)
+{
+ DIR *sys_dir, *evt_dir;
+ struct dirent *sys_next, *evt_next, sys_dirent, evt_dirent;
+ char evt_path[MAXPATHLEN];
+ char dir_path[MAXPATHLEN];
+
+ if (debugfs_valid_mountpoint(debugfs_path))
+ return 0;
+
+ sys_dir = opendir(debugfs_path);
+ if (!sys_dir)
+ return 0;
+
+ for_each_subsystem(sys_dir, sys_dirent, sys_next) {
+
+ snprintf(dir_path, MAXPATHLEN, "%s/%s", debugfs_path,
+ sys_dirent.d_name);
+ evt_dir = opendir(dir_path);
+ if (!evt_dir)
+ continue;
+
+ for_each_event(sys_dirent, evt_dir, evt_dirent, evt_next) {
+ snprintf(evt_path, MAXPATHLEN, "%s:%s",
+ sys_dirent.d_name, evt_dirent.d_name);
+ if (!strcmp(evt_path, event_string)) {
+ closedir(evt_dir);
+ closedir(sys_dir);
+ return 1;
+ }
+ }
+ closedir(evt_dir);
+ }
+ closedir(sys_dir);
+ return 0;
+}
+
+/*
* Print the help text for the event symbols:
*/
void print_events(void)
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index fc4ab3f..7ab4685 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -29,6 +29,7 @@ extern int parse_filter(const struct option *opt, const char *str, int unset);
#define EVENTS_HELP_MAX (128*1024)

extern void print_events(void);
+extern int is_valid_tracepoint(const char *event_string);

extern char debugfs_path[];
extern int valid_debugfs_mount(const char *debugfs);
--
1.6.3