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Message-ID: <tip-88cwdogxqomsy9tfr8r0as58@git.kernel.org>
Date: Thu, 13 Sep 2012 22:50:39 -0700
From: tip-bot for Arnaldo Carvalho de Melo <acme@...hat.com>
To: linux-tip-commits@...r.kernel.org
Cc: linux-kernel@...r.kernel.org, eranian@...gle.com, paulus@...ba.org,
acme@...hat.com, hpa@...or.com, mingo@...nel.org,
peterz@...radead.org, efault@....de, namhyung@...il.com,
jolsa@...hat.com, fweisbec@...il.com, dsahern@...il.com,
tglx@...utronix.de
Subject: [tip:perf/core] perf sched: Remove die() calls
Commit-ID: a116e05dcf61c8d758e0f0aed40325534aee2c13
Gitweb: http://git.kernel.org/tip/a116e05dcf61c8d758e0f0aed40325534aee2c13
Author: Arnaldo Carvalho de Melo <acme@...hat.com>
AuthorDate: Sat, 8 Sep 2012 22:53:06 -0300
Committer: Arnaldo Carvalho de Melo <acme@...hat.com>
CommitDate: Sun, 9 Sep 2012 11:39:02 -0300
perf sched: Remove die() calls
Just use pr_err() + return -1 and perf_session__process_events to abort
when some event would call die(), then let the perf's main() exit doing
whatever it needs.
Cc: David Ahern <dsahern@...il.com>
Cc: Frederic Weisbecker <fweisbec@...il.com>
Cc: Jiri Olsa <jolsa@...hat.com>
Cc: Mike Galbraith <efault@....de>
Cc: Namhyung Kim <namhyung@...il.com>
Cc: Paul Mackerras <paulus@...ba.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Stephane Eranian <eranian@...gle.com>
Link: http://lkml.kernel.org/n/tip-88cwdogxqomsy9tfr8r0as58@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
---
tools/perf/builtin-sched.c | 281 ++++++++++++++++++++++++++++----------------
1 files changed, 179 insertions(+), 102 deletions(-)
diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index a25a023..782f66d 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -423,8 +423,8 @@ static int self_open_counters(void)
fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
if (fd < 0)
- die("Error: sys_perf_event_open() syscall returned"
- "with %d (%s)\n", fd, strerror(errno));
+ pr_debug("Error: sys_perf_event_open() syscall returned"
+ "with %d (%s)\n", fd, strerror(errno));
return fd;
}
@@ -450,7 +450,8 @@ static void *thread_func(void *ctx)
sprintf(comm2, ":%s", this_task->comm);
prctl(PR_SET_NAME, comm2);
fd = self_open_counters();
-
+ if (fd < 0)
+ return NULL;
again:
ret = sem_post(&this_task->ready_for_work);
BUG_ON(ret);
@@ -726,30 +727,30 @@ struct trace_migrate_task_event {
};
struct trace_sched_handler {
- void (*switch_event)(struct trace_switch_event *,
- struct machine *,
- struct event_format *,
- struct perf_sample *sample);
-
- void (*runtime_event)(struct trace_runtime_event *,
- struct machine *,
- struct perf_sample *sample);
+ int (*switch_event)(struct trace_switch_event *event,
+ struct machine *machine,
+ struct event_format *tp_format,
+ struct perf_sample *sample);
- void (*wakeup_event)(struct trace_wakeup_event *,
- struct machine *,
- struct event_format *,
+ int (*runtime_event)(struct trace_runtime_event *event,
+ struct machine *machine,
struct perf_sample *sample);
- void (*fork_event)(struct trace_fork_event *,
- struct event_format *event);
+ int (*wakeup_event)(struct trace_wakeup_event *event,
+ struct machine *machine,
+ struct event_format *tp_format,
+ struct perf_sample *sample);
- void (*migrate_task_event)(struct trace_migrate_task_event *,
- struct machine *machine,
- struct perf_sample *sample);
+ int (*fork_event)(struct trace_fork_event *event,
+ struct event_format *tp_format);
+
+ int (*migrate_task_event)(struct trace_migrate_task_event *event,
+ struct machine *machine,
+ struct perf_sample *sample);
};
-static void
+static int
replay_wakeup_event(struct trace_wakeup_event *wakeup_event,
struct machine *machine __used,
struct event_format *event, struct perf_sample *sample)
@@ -769,11 +770,12 @@ replay_wakeup_event(struct trace_wakeup_event *wakeup_event,
wakee = register_pid(wakeup_event->pid, wakeup_event->comm);
add_sched_event_wakeup(waker, sample->time, wakee);
+ return 0;
}
static u64 cpu_last_switched[MAX_CPUS];
-static void
+static int
replay_switch_event(struct trace_switch_event *switch_event,
struct machine *machine __used,
struct event_format *event,
@@ -788,7 +790,7 @@ replay_switch_event(struct trace_switch_event *switch_event,
printf("sched_switch event %p\n", event);
if (cpu >= MAX_CPUS || cpu < 0)
- return;
+ return 0;
timestamp0 = cpu_last_switched[cpu];
if (timestamp0)
@@ -796,8 +798,10 @@ replay_switch_event(struct trace_switch_event *switch_event,
else
delta = 0;
- if (delta < 0)
- die("hm, delta: %" PRIu64 " < 0 ?\n", delta);
+ if (delta < 0) {
+ pr_debug("hm, delta: %" PRIu64 " < 0 ?\n", delta);
+ return -1;
+ }
if (verbose) {
printf(" ... switch from %s/%d to %s/%d [ran %" PRIu64 " nsecs]\n",
@@ -813,10 +817,12 @@ replay_switch_event(struct trace_switch_event *switch_event,
add_sched_event_run(prev, timestamp, delta);
add_sched_event_sleep(prev, timestamp, switch_event->prev_state);
+
+ return 0;
}
-static void
+static int
replay_fork_event(struct trace_fork_event *fork_event,
struct event_format *event)
{
@@ -827,6 +833,7 @@ replay_fork_event(struct trace_fork_event *fork_event,
}
register_pid(fork_event->parent_pid, fork_event->parent_comm);
register_pid(fork_event->child_pid, fork_event->child_comm);
+ return 0;
}
static struct trace_sched_handler replay_ops = {
@@ -911,22 +918,26 @@ __thread_latency_insert(struct rb_root *root, struct work_atoms *data,
rb_insert_color(&data->node, root);
}
-static void thread_atoms_insert(struct thread *thread)
+static int thread_atoms_insert(struct thread *thread)
{
struct work_atoms *atoms = zalloc(sizeof(*atoms));
- if (!atoms)
- die("No memory");
+ if (!atoms) {
+ pr_err("No memory at %s\n", __func__);
+ return -1;
+ }
atoms->thread = thread;
INIT_LIST_HEAD(&atoms->work_list);
__thread_latency_insert(&atom_root, atoms, &cmp_pid);
+ return 0;
}
-static void
+static int
latency_fork_event(struct trace_fork_event *fork_event __used,
struct event_format *event __used)
{
/* should insert the newcomer */
+ return 0;
}
__used
@@ -937,14 +948,16 @@ static char sched_out_state(struct trace_switch_event *switch_event)
return str[switch_event->prev_state];
}
-static void
+static int
add_sched_out_event(struct work_atoms *atoms,
char run_state,
u64 timestamp)
{
struct work_atom *atom = zalloc(sizeof(*atom));
- if (!atom)
- die("Non memory");
+ if (!atom) {
+ pr_err("Non memory at %s", __func__);
+ return -1;
+ }
atom->sched_out_time = timestamp;
@@ -954,6 +967,7 @@ add_sched_out_event(struct work_atoms *atoms,
}
list_add_tail(&atom->list, &atoms->work_list);
+ return 0;
}
static void
@@ -1000,7 +1014,7 @@ add_sched_in_event(struct work_atoms *atoms, u64 timestamp)
atoms->nb_atoms++;
}
-static void
+static int
latency_switch_event(struct trace_switch_event *switch_event,
struct machine *machine,
struct event_format *event __used,
@@ -1021,38 +1035,49 @@ latency_switch_event(struct trace_switch_event *switch_event,
else
delta = 0;
- if (delta < 0)
- die("hm, delta: %" PRIu64 " < 0 ?\n", delta);
-
+ if (delta < 0) {
+ pr_err("hm, delta: %" PRIu64 " < 0 ?\n", delta);
+ return -1;
+ }
sched_out = machine__findnew_thread(machine, switch_event->prev_pid);
sched_in = machine__findnew_thread(machine, switch_event->next_pid);
out_events = thread_atoms_search(&atom_root, sched_out, &cmp_pid);
if (!out_events) {
- thread_atoms_insert(sched_out);
+ if (thread_atoms_insert(sched_out))
+ return -1;
out_events = thread_atoms_search(&atom_root, sched_out, &cmp_pid);
- if (!out_events)
- die("out-event: Internal tree error");
+ if (!out_events) {
+ pr_err("out-event: Internal tree error");
+ return -1;
+ }
}
- add_sched_out_event(out_events, sched_out_state(switch_event), timestamp);
+ if (add_sched_out_event(out_events, sched_out_state(switch_event), timestamp))
+ return -1;
in_events = thread_atoms_search(&atom_root, sched_in, &cmp_pid);
if (!in_events) {
- thread_atoms_insert(sched_in);
+ if (thread_atoms_insert(sched_in))
+ return -1;
in_events = thread_atoms_search(&atom_root, sched_in, &cmp_pid);
- if (!in_events)
- die("in-event: Internal tree error");
+ if (!in_events) {
+ pr_err("in-event: Internal tree error");
+ return -1;
+ }
/*
* Take came in we have not heard about yet,
* add in an initial atom in runnable state:
*/
- add_sched_out_event(in_events, 'R', timestamp);
+ if (add_sched_out_event(in_events, 'R', timestamp))
+ return -1;
}
add_sched_in_event(in_events, timestamp);
+
+ return 0;
}
-static void
+static int
latency_runtime_event(struct trace_runtime_event *runtime_event,
struct machine *machine, struct perf_sample *sample)
{
@@ -1063,17 +1088,22 @@ latency_runtime_event(struct trace_runtime_event *runtime_event,
BUG_ON(cpu >= MAX_CPUS || cpu < 0);
if (!atoms) {
- thread_atoms_insert(thread);
+ if (thread_atoms_insert(thread))
+ return -1;
atoms = thread_atoms_search(&atom_root, thread, &cmp_pid);
- if (!atoms)
- die("in-event: Internal tree error");
- add_sched_out_event(atoms, 'R', timestamp);
+ if (!atoms) {
+ pr_debug("in-event: Internal tree error");
+ return -1;
+ }
+ if (add_sched_out_event(atoms, 'R', timestamp))
+ return -1;
}
add_runtime_event(atoms, runtime_event->runtime, timestamp);
+ return 0;
}
-static void
+static int
latency_wakeup_event(struct trace_wakeup_event *wakeup_event,
struct machine *machine, struct event_format *event __used,
struct perf_sample *sample)
@@ -1085,16 +1115,20 @@ latency_wakeup_event(struct trace_wakeup_event *wakeup_event,
/* Note for later, it may be interesting to observe the failing cases */
if (!wakeup_event->success)
- return;
+ return 0;
wakee = machine__findnew_thread(machine, wakeup_event->pid);
atoms = thread_atoms_search(&atom_root, wakee, &cmp_pid);
if (!atoms) {
- thread_atoms_insert(wakee);
+ if (thread_atoms_insert(wakee))
+ return -1;
atoms = thread_atoms_search(&atom_root, wakee, &cmp_pid);
- if (!atoms)
- die("wakeup-event: Internal tree error");
- add_sched_out_event(atoms, 'S', timestamp);
+ if (!atoms) {
+ pr_debug("wakeup-event: Internal tree error");
+ return -1;
+ }
+ if (add_sched_out_event(atoms, 'S', timestamp))
+ return -1;
}
BUG_ON(list_empty(&atoms->work_list));
@@ -1112,14 +1146,15 @@ latency_wakeup_event(struct trace_wakeup_event *wakeup_event,
nr_timestamps++;
if (atom->sched_out_time > timestamp) {
nr_unordered_timestamps++;
- return;
+ return 0;
}
atom->state = THREAD_WAIT_CPU;
atom->wake_up_time = timestamp;
+ return 0;
}
-static void
+static int
latency_migrate_task_event(struct trace_migrate_task_event *migrate_task_event,
struct machine *machine, struct perf_sample *sample)
{
@@ -1132,17 +1167,21 @@ latency_migrate_task_event(struct trace_migrate_task_event *migrate_task_event,
* Only need to worry about migration when profiling one CPU.
*/
if (profile_cpu == -1)
- return;
+ return 0;
migrant = machine__findnew_thread(machine, migrate_task_event->pid);
atoms = thread_atoms_search(&atom_root, migrant, &cmp_pid);
if (!atoms) {
- thread_atoms_insert(migrant);
+ if (thread_atoms_insert(migrant))
+ return -1;
register_pid(migrant->pid, migrant->comm);
atoms = thread_atoms_search(&atom_root, migrant, &cmp_pid);
- if (!atoms)
- die("migration-event: Internal tree error");
- add_sched_out_event(atoms, 'R', timestamp);
+ if (!atoms) {
+ pr_debug("migration-event: Internal tree error");
+ return -1;
+ }
+ if (add_sched_out_event(atoms, 'R', timestamp))
+ return -1;
}
BUG_ON(list_empty(&atoms->work_list));
@@ -1154,6 +1193,8 @@ latency_migrate_task_event(struct trace_migrate_task_event *migrate_task_event,
if (atom->sched_out_time > timestamp)
nr_unordered_timestamps++;
+
+ return 0;
}
static struct trace_sched_handler lat_ops = {
@@ -1328,7 +1369,7 @@ static void sort_lat(void)
static struct trace_sched_handler *trace_handler;
-static void
+static int
process_sched_wakeup_event(struct perf_tool *tool __used,
struct event_format *event,
struct perf_sample *sample,
@@ -1337,6 +1378,7 @@ process_sched_wakeup_event(struct perf_tool *tool __used,
{
void *data = sample->raw_data;
struct trace_wakeup_event wakeup_event;
+ int err = 0;
FILL_COMMON_FIELDS(wakeup_event, event, data);
@@ -1347,7 +1389,9 @@ process_sched_wakeup_event(struct perf_tool *tool __used,
FILL_FIELD(wakeup_event, cpu, event, data);
if (trace_handler->wakeup_event)
- trace_handler->wakeup_event(&wakeup_event, machine, event, sample);
+ err = trace_handler->wakeup_event(&wakeup_event, machine, event, sample);
+
+ return err;
}
/*
@@ -1363,7 +1407,7 @@ static struct thread *curr_thread[MAX_CPUS];
static char next_shortname1 = 'A';
static char next_shortname2 = '0';
-static void
+static int
map_switch_event(struct trace_switch_event *switch_event,
struct machine *machine,
struct event_format *event __used,
@@ -1387,9 +1431,10 @@ map_switch_event(struct trace_switch_event *switch_event,
else
delta = 0;
- if (delta < 0)
- die("hm, delta: %" PRIu64 " < 0 ?\n", delta);
-
+ if (delta < 0) {
+ pr_debug("hm, delta: %" PRIu64 " < 0 ?\n", delta);
+ return -1;
+ }
sched_out = machine__findnew_thread(machine, switch_event->prev_pid);
sched_in = machine__findnew_thread(machine, switch_event->next_pid);
@@ -1438,16 +1483,18 @@ map_switch_event(struct trace_switch_event *switch_event,
} else {
printf("\n");
}
+
+ return 0;
}
-static void
+static int
process_sched_switch_event(struct perf_tool *tool __used,
struct event_format *event,
struct perf_sample *sample,
struct machine *machine,
struct thread *thread __used)
{
- int this_cpu = sample->cpu;
+ int this_cpu = sample->cpu, err = 0;
void *data = sample->raw_data;
struct trace_switch_event switch_event;
@@ -1470,12 +1517,13 @@ process_sched_switch_event(struct perf_tool *tool __used,
nr_context_switch_bugs++;
}
if (trace_handler->switch_event)
- trace_handler->switch_event(&switch_event, machine, event, sample);
+ err = trace_handler->switch_event(&switch_event, machine, event, sample);
curr_pid[this_cpu] = switch_event.next_pid;
+ return err;
}
-static void
+static int
process_sched_runtime_event(struct perf_tool *tool __used,
struct event_format *event,
struct perf_sample *sample,
@@ -1484,6 +1532,7 @@ process_sched_runtime_event(struct perf_tool *tool __used,
{
void *data = sample->raw_data;
struct trace_runtime_event runtime_event;
+ int err = 0;
FILL_ARRAY(runtime_event, comm, event, data);
FILL_FIELD(runtime_event, pid, event, data);
@@ -1491,10 +1540,12 @@ process_sched_runtime_event(struct perf_tool *tool __used,
FILL_FIELD(runtime_event, vruntime, event, data);
if (trace_handler->runtime_event)
- trace_handler->runtime_event(&runtime_event, machine, sample);
+ err = trace_handler->runtime_event(&runtime_event, machine, sample);
+
+ return err;
}
-static void
+static int
process_sched_fork_event(struct perf_tool *tool __used,
struct event_format *event,
struct perf_sample *sample,
@@ -1503,6 +1554,7 @@ process_sched_fork_event(struct perf_tool *tool __used,
{
void *data = sample->raw_data;
struct trace_fork_event fork_event;
+ int err = 0;
FILL_COMMON_FIELDS(fork_event, event, data);
@@ -1512,10 +1564,12 @@ process_sched_fork_event(struct perf_tool *tool __used,
FILL_FIELD(fork_event, child_pid, event, data);
if (trace_handler->fork_event)
- trace_handler->fork_event(&fork_event, event);
+ err = trace_handler->fork_event(&fork_event, event);
+
+ return err;
}
-static void
+static int
process_sched_exit_event(struct perf_tool *tool __used,
struct event_format *event,
struct perf_sample *sample __used,
@@ -1524,9 +1578,11 @@ process_sched_exit_event(struct perf_tool *tool __used,
{
if (verbose)
printf("sched_exit event %p\n", event);
+
+ return 0;
}
-static void
+static int
process_sched_migrate_task_event(struct perf_tool *tool __used,
struct event_format *event,
struct perf_sample *sample,
@@ -1535,6 +1591,7 @@ process_sched_migrate_task_event(struct perf_tool *tool __used,
{
void *data = sample->raw_data;
struct trace_migrate_task_event migrate_task_event;
+ int err = 0;
FILL_COMMON_FIELDS(migrate_task_event, event, data);
@@ -1544,13 +1601,16 @@ process_sched_migrate_task_event(struct perf_tool *tool __used,
FILL_FIELD(migrate_task_event, cpu, event, data);
if (trace_handler->migrate_task_event)
- trace_handler->migrate_task_event(&migrate_task_event, machine, sample);
+ err = trace_handler->migrate_task_event(&migrate_task_event, machine, sample);
+
+ return err;
}
-typedef void (*tracepoint_handler)(struct perf_tool *tool, struct event_format *event,
- struct perf_sample *sample,
- struct machine *machine,
- struct thread *thread);
+typedef int (*tracepoint_handler)(struct perf_tool *tool,
+ struct event_format *tp_format,
+ struct perf_sample *sample,
+ struct machine *machine,
+ struct thread *thread);
static int perf_sched__process_tracepoint_sample(struct perf_tool *tool __used,
union perf_event *event __used,
@@ -1559,6 +1619,7 @@ static int perf_sched__process_tracepoint_sample(struct perf_tool *tool __used,
struct machine *machine)
{
struct thread *thread = machine__findnew_thread(machine, sample->pid);
+ int err = 0;
if (thread == NULL) {
pr_debug("problem processing %s event, skipping it.\n",
@@ -1571,10 +1632,10 @@ static int perf_sched__process_tracepoint_sample(struct perf_tool *tool __used,
if (evsel->handler.func != NULL) {
tracepoint_handler f = evsel->handler.func;
- f(tool, evsel->tp_format, sample, machine, thread);
+ err = f(tool, evsel->tp_format, sample, machine, thread);
}
- return 0;
+ return err;
}
static struct perf_tool perf_sched = {
@@ -1585,9 +1646,8 @@ static struct perf_tool perf_sched = {
.ordered_samples = true,
};
-static void read_events(bool destroy, struct perf_session **psession)
+static int read_events(bool destroy, struct perf_session **psession)
{
- int err = -EINVAL;
const struct perf_evsel_str_handler handlers[] = {
{ "sched:sched_switch", process_sched_switch_event, },
{ "sched:sched_stat_runtime", process_sched_runtime_event, },
@@ -1600,16 +1660,20 @@ static void read_events(bool destroy, struct perf_session **psession)
struct perf_session *session;
session = perf_session__new(input_name, O_RDONLY, 0, false, &perf_sched);
- if (session == NULL)
- die("No Memory");
+ if (session == NULL) {
+ pr_debug("No Memory for session\n");
+ return -1;
+ }
- err = perf_session__set_tracepoints_handlers(session, handlers);
- assert(err == 0);
+ if (perf_session__set_tracepoints_handlers(session, handlers))
+ goto out_delete;
if (perf_session__has_traces(session, "record -R")) {
- err = perf_session__process_events(session, &perf_sched);
- if (err)
- die("Failed to process events, error %d", err);
+ int err = perf_session__process_events(session, &perf_sched);
+ if (err) {
+ pr_err("Failed to process events, error %d", err);
+ goto out_delete;
+ }
nr_events = session->hists.stats.nr_events[0];
nr_lost_events = session->hists.stats.total_lost;
@@ -1621,6 +1685,12 @@ static void read_events(bool destroy, struct perf_session **psession)
if (psession)
*psession = session;
+
+ return 0;
+
+out_delete:
+ perf_session__delete(session);
+ return -1;
}
static void print_bad_events(void)
@@ -1653,13 +1723,14 @@ static void print_bad_events(void)
}
}
-static void __cmd_lat(void)
+static int __cmd_lat(void)
{
struct rb_node *next;
struct perf_session *session;
setup_pager();
- read_events(false, &session);
+ if (read_events(false, &session))
+ return -1;
sort_lat();
printf("\n ---------------------------------------------------------------------------------------------------------------\n");
@@ -1686,6 +1757,7 @@ static void __cmd_lat(void)
printf("\n");
perf_session__delete(session);
+ return 0;
}
static struct trace_sched_handler map_ops = {
@@ -1695,16 +1767,18 @@ static struct trace_sched_handler map_ops = {
.fork_event = NULL,
};
-static void __cmd_map(void)
+static int __cmd_map(void)
{
max_cpu = sysconf(_SC_NPROCESSORS_CONF);
setup_pager();
- read_events(true, NULL);
+ if (read_events(true, NULL))
+ return -1;
print_bad_events();
+ return 0;
}
-static void __cmd_replay(void)
+static int __cmd_replay(void)
{
unsigned long i;
@@ -1713,7 +1787,8 @@ static void __cmd_replay(void)
test_calibrations();
- read_events(true, NULL);
+ if (read_events(true, NULL))
+ return -1;
printf("nr_run_events: %ld\n", nr_run_events);
printf("nr_sleep_events: %ld\n", nr_sleep_events);
@@ -1734,6 +1809,8 @@ static void __cmd_replay(void)
printf("------------------------------------------------------------\n");
for (i = 0; i < replay_repeat; i++)
run_one_test();
+
+ return 0;
}
@@ -1865,11 +1942,11 @@ int cmd_sched(int argc, const char **argv, const char *prefix __used)
usage_with_options(latency_usage, latency_options);
}
setup_sorting();
- __cmd_lat();
+ return __cmd_lat();
} else if (!strcmp(argv[0], "map")) {
trace_handler = &map_ops;
setup_sorting();
- __cmd_map();
+ return __cmd_map();
} else if (!strncmp(argv[0], "rep", 3)) {
trace_handler = &replay_ops;
if (argc) {
@@ -1877,7 +1954,7 @@ int cmd_sched(int argc, const char **argv, const char *prefix __used)
if (argc)
usage_with_options(replay_usage, replay_options);
}
- __cmd_replay();
+ return __cmd_replay();
} else {
usage_with_options(sched_usage, sched_options);
}
--
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