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Diffstat (limited to 'src/libsystemd/sd-event/sd-event.c')
-rw-r--r--src/libsystemd/sd-event/sd-event.c108
1 files changed, 86 insertions, 22 deletions
diff --git a/src/libsystemd/sd-event/sd-event.c b/src/libsystemd/sd-event/sd-event.c
index 3191b458d1..eeb3453919 100644
--- a/src/libsystemd/sd-event/sd-event.c
+++ b/src/libsystemd/sd-event/sd-event.c
@@ -37,6 +37,7 @@
#include "process-util.h"
#include "set.h"
#include "signal-util.h"
+#include "string-table.h"
#include "string-util.h"
#include "time-util.h"
#include "util.h"
@@ -60,6 +61,23 @@ typedef enum EventSourceType {
_SOURCE_EVENT_SOURCE_TYPE_INVALID = -1
} EventSourceType;
+static const char* const event_source_type_table[_SOURCE_EVENT_SOURCE_TYPE_MAX] = {
+ [SOURCE_IO] = "io",
+ [SOURCE_TIME_REALTIME] = "realtime",
+ [SOURCE_TIME_BOOTTIME] = "bootime",
+ [SOURCE_TIME_MONOTONIC] = "monotonic",
+ [SOURCE_TIME_REALTIME_ALARM] = "realtime-alarm",
+ [SOURCE_TIME_BOOTTIME_ALARM] = "boottime-alarm",
+ [SOURCE_SIGNAL] = "signal",
+ [SOURCE_CHILD] = "child",
+ [SOURCE_DEFER] = "defer",
+ [SOURCE_POST] = "post",
+ [SOURCE_EXIT] = "exit",
+ [SOURCE_WATCHDOG] = "watchdog",
+};
+
+DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(event_source_type, int);
+
/* All objects we use in epoll events start with this value, so that
* we know how to dispatch it */
typedef enum WakeupType {
@@ -207,6 +225,7 @@ struct sd_event {
bool exit_requested:1;
bool need_process_child:1;
bool watchdog:1;
+ bool profile_delays:1;
int exit_code;
@@ -218,6 +237,9 @@ struct sd_event {
unsigned n_sources;
LIST_HEAD(sd_event_source, sources);
+
+ usec_t last_run, last_log;
+ unsigned delays[sizeof(usec_t) * 8];
};
static void source_disconnect(sd_event_source *s);
@@ -305,6 +327,10 @@ static int earliest_time_prioq_compare(const void *a, const void *b) {
return 0;
}
+static usec_t time_event_source_latest(const sd_event_source *s) {
+ return usec_add(s->time.next, s->time.accuracy);
+}
+
static int latest_time_prioq_compare(const void *a, const void *b) {
const sd_event_source *x = a, *y = b;
@@ -324,9 +350,9 @@ static int latest_time_prioq_compare(const void *a, const void *b) {
return 1;
/* Order by time */
- if (x->time.next + x->time.accuracy < y->time.next + y->time.accuracy)
+ if (time_event_source_latest(x) < time_event_source_latest(y))
return -1;
- if (x->time.next + x->time.accuracy > y->time.next + y->time.accuracy)
+ if (time_event_source_latest(x) > time_event_source_latest(y))
return 1;
return 0;
@@ -426,6 +452,11 @@ _public_ int sd_event_new(sd_event** ret) {
goto fail;
}
+ if (secure_getenv("SD_EVENT_PROFILE_DELAYS")) {
+ log_debug("Event loop profiling enabled. Logarithmic histogram of event loop iterations in the range 2^0 ... 2^63 us will be logged every 5s.");
+ e->profile_delays = true;
+ }
+
*ret = e;
return 0;
@@ -482,7 +513,8 @@ static void source_io_unregister(sd_event_source *s) {
r = epoll_ctl(s->event->epoll_fd, EPOLL_CTL_DEL, s->io.fd, NULL);
if (r < 0)
- log_debug_errno(errno, "Failed to remove source %s from epoll: %m", strna(s->description));
+ log_debug_errno(errno, "Failed to remove source %s (type %s) from epoll: %m",
+ strna(s->description), event_source_type_to_string(s->type));
s->io.registered = false;
}
@@ -633,8 +665,10 @@ static int event_make_signal_data(
d->priority = priority;
r = hashmap_put(e->signal_data, &d->priority, d);
- if (r < 0)
+ if (r < 0) {
+ free(d);
return r;
+ }
added = true;
}
@@ -1036,7 +1070,6 @@ _public_ int sd_event_add_time(
int r;
assert_return(e, -EINVAL);
- assert_return(usec != (uint64_t) -1, -EINVAL);
assert_return(accuracy != (uint64_t) -1, -EINVAL);
assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
assert_return(!event_pid_changed(e), -ECHILD);
@@ -1726,7 +1759,6 @@ _public_ int sd_event_source_set_time(sd_event_source *s, uint64_t usec) {
struct clock_data *d;
assert_return(s, -EINVAL);
- assert_return(usec != (uint64_t) -1, -EINVAL);
assert_return(EVENT_SOURCE_IS_TIME(s->type), -EDOM);
assert_return(s->event->state != SD_EVENT_FINISHED, -ESTALE);
assert_return(!event_pid_changed(s->event), -ECHILD);
@@ -1856,6 +1888,8 @@ static usec_t sleep_between(sd_event *e, usec_t a, usec_t b) {
if (a <= 0)
return 0;
+ if (a >= USEC_INFINITY)
+ return USEC_INFINITY;
if (b <= a + 1)
return a;
@@ -1945,7 +1979,7 @@ static int event_arm_timer(
d->needs_rearm = false;
a = prioq_peek(d->earliest);
- if (!a || a->enabled == SD_EVENT_OFF) {
+ if (!a || a->enabled == SD_EVENT_OFF || a->time.next == USEC_INFINITY) {
if (d->fd < 0)
return 0;
@@ -1965,7 +1999,7 @@ static int event_arm_timer(
b = prioq_peek(d->latest);
assert_se(b && b->enabled != SD_EVENT_OFF);
- t = sleep_between(e, a->time.next, b->time.next + b->time.accuracy);
+ t = sleep_between(e, a->time.next, time_event_source_latest(b));
if (d->next == t)
return 0;
@@ -2281,12 +2315,9 @@ static int source_dispatch(sd_event_source *s) {
s->dispatching = false;
- if (r < 0) {
- if (s->description)
- log_debug_errno(r, "Event source '%s' returned error, disabling: %m", s->description);
- else
- log_debug_errno(r, "Event source %p returned error, disabling: %m", s);
- }
+ if (r < 0)
+ log_debug_errno(r, "Event source %s (type %s) returned error, disabling: %m",
+ strna(s->description), event_source_type_to_string(s->type));
if (s->n_ref == 0)
source_free(s);
@@ -2319,12 +2350,9 @@ static int event_prepare(sd_event *e) {
r = s->prepare(s, s->userdata);
s->dispatching = false;
- if (r < 0) {
- if (s->description)
- log_debug_errno(r, "Prepare callback of event source '%s' returned error, disabling: %m", s->description);
- else
- log_debug_errno(r, "Prepare callback of event source %p returned error, disabling: %m", s);
- }
+ if (r < 0)
+ log_debug_errno(r, "Prepare callback of event source %s (type %s) returned error, disabling: %m",
+ strna(s->description), event_source_type_to_string(s->type));
if (s->n_ref == 0)
source_free(s);
@@ -2609,6 +2637,18 @@ _public_ int sd_event_dispatch(sd_event *e) {
return 1;
}
+static void event_log_delays(sd_event *e) {
+ char b[ELEMENTSOF(e->delays) * DECIMAL_STR_MAX(unsigned) + 1];
+ unsigned i;
+ int o;
+
+ for (i = o = 0; i < ELEMENTSOF(e->delays); i++) {
+ o += snprintf(&b[o], sizeof(b) - o, "%u ", e->delays[i]);
+ e->delays[i] = 0;
+ }
+ log_debug("Event loop iterations: %.*s", o, b);
+}
+
_public_ int sd_event_run(sd_event *e, uint64_t timeout) {
int r;
@@ -2617,11 +2657,30 @@ _public_ int sd_event_run(sd_event *e, uint64_t timeout) {
assert_return(e->state != SD_EVENT_FINISHED, -ESTALE);
assert_return(e->state == SD_EVENT_INITIAL, -EBUSY);
+ if (e->profile_delays && e->last_run) {
+ usec_t this_run;
+ unsigned l;
+
+ this_run = now(CLOCK_MONOTONIC);
+
+ l = u64log2(this_run - e->last_run);
+ assert(l < sizeof(e->delays));
+ e->delays[l]++;
+
+ if (this_run - e->last_log >= 5*USEC_PER_SEC) {
+ event_log_delays(e);
+ e->last_log = this_run;
+ }
+ }
+
r = sd_event_prepare(e);
if (r == 0)
/* There was nothing? Then wait... */
r = sd_event_wait(e, timeout);
+ if (e->profile_delays)
+ e->last_run = now(CLOCK_MONOTONIC);
+
if (r > 0) {
/* There's something now, then let's dispatch it */
r = sd_event_dispatch(e);
@@ -2698,6 +2757,12 @@ _public_ int sd_event_now(sd_event *e, clockid_t clock, uint64_t *usec) {
assert_return(e, -EINVAL);
assert_return(usec, -EINVAL);
assert_return(!event_pid_changed(e), -ECHILD);
+ assert_return(IN_SET(clock,
+ CLOCK_REALTIME,
+ CLOCK_REALTIME_ALARM,
+ CLOCK_MONOTONIC,
+ CLOCK_BOOTTIME,
+ CLOCK_BOOTTIME_ALARM), -EOPNOTSUPP);
if (!dual_timestamp_is_set(&e->timestamp)) {
/* Implicitly fall back to now() if we never ran
@@ -2717,8 +2782,7 @@ _public_ int sd_event_now(sd_event *e, clockid_t clock, uint64_t *usec) {
*usec = e->timestamp.monotonic;
break;
- case CLOCK_BOOTTIME:
- case CLOCK_BOOTTIME_ALARM:
+ default:
*usec = e->timestamp_boottime;
break;
}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-07-26 03:42:15 +0000