summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLennart Poettering <lennart@poettering.net>2010-01-29 04:42:57 +0100
committerLennart Poettering <lennart@poettering.net>2010-01-29 04:42:57 +0100
commit1e2e81336b2d7691d51a6f3e82df9ae20c22aee1 (patch)
treeeedbc1b5b0d24efcc6437f987efa4fbdf9b5a986
parentc20cae324d93e7fcdb8618e37c3ac377d87edb97 (diff)
ratelimit start requests
-rw-r--r--Makefile3
-rw-r--r--ratelimit.c43
-rw-r--r--ratelimit.h36
-rw-r--r--service.c8
-rw-r--r--service.h3
5 files changed, 92 insertions, 1 deletions
diff --git a/Makefile b/Makefile
index d35620e0c1..e5cb6b5daa 100644
--- a/Makefile
+++ b/Makefile
@@ -22,7 +22,8 @@ COMMON= \
socket.o \
timer.o \
load-dropin.o \
- execute.o
+ execute.o \
+ ratelimit.o
all: systemd test-engine test-job-type systemd-logger
diff --git a/ratelimit.c b/ratelimit.c
new file mode 100644
index 0000000000..d9eb493496
--- /dev/null
+++ b/ratelimit.c
@@ -0,0 +1,43 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+#include <assert.h>
+
+#include "ratelimit.h"
+#include "log.h"
+
+/* Modelled after Linux' lib/ratelimit.c by Dave Young
+ * <hidave.darkstar@gmail.com>, which is licensed GPLv2. */
+
+bool ratelimit_test(RateLimit *r) {
+ usec_t timestamp;
+
+ timestamp = now(CLOCK_MONOTONIC);
+
+ assert(r);
+ assert(r->interval > 0);
+ assert(r->burst > 0);
+
+ if (r->begin <= 0 ||
+ r->begin + r->interval < timestamp) {
+
+ if (r->n_missed > 0)
+ log_warning("%u events suppressed", r->n_missed);
+
+ r->begin = timestamp;
+
+ /* Reset counters */
+ r->n_printed = 0;
+ r->n_missed = 0;
+ goto good;
+ }
+
+ if (r->n_printed <= r->burst)
+ goto good;
+
+ r->n_missed++;
+ return false;
+
+good:
+ r->n_printed++;
+ return true;
+}
diff --git a/ratelimit.h b/ratelimit.h
new file mode 100644
index 0000000000..7f018389c3
--- /dev/null
+++ b/ratelimit.h
@@ -0,0 +1,36 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+#ifndef fooratelimithfoo
+#define fooratelimithfoo
+
+#include "util.h"
+
+typedef struct RateLimit {
+ usec_t interval;
+ unsigned burst;
+ unsigned n_printed, n_missed;
+ usec_t begin;
+} RateLimit;
+
+#define RATELIMIT_DEFINE(_name, _interval, _burst) \
+ RateLimit _name = { \
+ .interval = (_interval), \
+ .burst = (_burst), \
+ .n_printed = 0, \
+ .n_missed = 0, \
+ .begin = 0 \
+ }
+
+#define RATELIMIT_INIT(v, _interval, _burst) \
+ do { \
+ RateLimit *r = &(v); \
+ r->interval = (_interval); \
+ r->burst = (_burst); \
+ r->n_printed = 0; \
+ r->n_missed = 0; \
+ r->begin = 0; \
+ } while (false);
+
+bool ratelimit_test(RateLimit *r);
+
+#endif
diff --git a/service.c b/service.c
index 70299dd065..2943da6e80 100644
--- a/service.c
+++ b/service.c
@@ -100,6 +100,8 @@ static int service_init(Unit *u) {
s->state = SERVICE_DEAD;
+ RATELIMIT_INIT(s->ratelimit, 10*USEC_PER_SEC, 5);
+
/* Load a .service file */
if ((r = unit_load_fragment(u)) < 0) {
service_done(u);
@@ -734,6 +736,12 @@ static int service_start(Unit *u) {
assert(s->state == SERVICE_DEAD || s->state == SERVICE_MAINTAINANCE || s->state == SERVICE_AUTO_RESTART);
+ /* Make sure we don't enter a busy loop of some kind. */
+ if (!ratelimit_test(&s->ratelimit)) {
+ log_warning("%s start request repeated too quickly, refusing to start.", unit_id(u));
+ return -EAGAIN;
+ }
+
s->failure = false;
s->main_pid_known = false;
diff --git a/service.h b/service.h
index f9dbfea5e6..38b5438d4e 100644
--- a/service.h
+++ b/service.h
@@ -6,6 +6,7 @@
typedef struct Service Service;
#include "unit.h"
+#include "ratelimit.h"
typedef enum ServiceState {
SERVICE_DEAD,
@@ -71,6 +72,8 @@ struct Service {
bool failure:1; /* if we shut down, remember why */
Watch timer_watch;
+
+ RateLimit ratelimit;
};
const UnitVTable service_vtable;