#include "hmap.h"
#include "ovs-thread.h"
#include "signals.h"
+#include "seq.h"
#include "unixctl.h"
#include "util.h"
#include "vlog.h"
struct clock {
clockid_t id; /* CLOCK_MONOTONIC or CLOCK_REALTIME. */
- /* Features for use by unit tests. Protected by 'rwlock'. */
- struct ovs_rwlock rwlock;
- struct timespec warp; /* Offset added for unit tests. */
- bool stopped; /* Disables real-time updates if true. */
-
- struct timespec cache; /* Last time read from kernel. */
+ /* Features for use by unit tests. Protected by 'mutex'. */
+ struct ovs_mutex mutex;
+ atomic_bool slow_path; /* True if warped or stopped. */
+ struct timespec warp OVS_GUARDED; /* Offset added for unit tests. */
+ bool stopped OVS_GUARDED; /* Disable real-time updates if true. */
+ struct timespec cache OVS_GUARDED; /* Last time read from kernel. */
};
/* Our clocks. */
/* The monotonic time at which the time module was initialized. */
static long long int boot_time;
+/* True only when timeval_dummy_register() is called. */
+static bool timewarp_enabled;
+/* Reference to the seq struct. Threads other than main thread can
+ * wait on timewarp_seq and be waken up when time is warped. */
+static struct seq *timewarp_seq;
+/* Last value of 'timewarp_seq'. */
+DEFINE_STATIC_PER_THREAD_DATA(uint64_t, last_seq, 0);
+
/* Monotonic time in milliseconds at which to die with SIGALRM (if not
* LLONG_MAX). */
static long long int deadline = LLONG_MAX;
{
memset(c, 0, sizeof *c);
c->id = id;
- ovs_rwlock_init(&c->rwlock);
+ ovs_mutex_init(&c->mutex);
+ atomic_init(&c->slow_path, false);
xclock_gettime(c->id, &c->cache);
+ timewarp_seq = seq_create();
}
static void
static void
time_timespec__(struct clock *c, struct timespec *ts)
{
+ bool slow_path;
+
time_init();
- if (!c->stopped) {
+ atomic_read_explicit(&c->slow_path, &slow_path, memory_order_relaxed);
+ if (!slow_path) {
xclock_gettime(c->id, ts);
} else {
- ovs_rwlock_rdlock(&c->rwlock);
- timespec_add(ts, &c->cache, &c->warp);
- ovs_rwlock_unlock(&c->rwlock);
+ struct timespec warp;
+ struct timespec cache;
+ bool stopped;
+
+ ovs_mutex_lock(&c->mutex);
+ stopped = c->stopped;
+ warp = c->warp;
+ cache = c->cache;
+ ovs_mutex_unlock(&c->mutex);
+
+ if (!stopped) {
+ xclock_gettime(c->id, &cache);
+ }
+ timespec_add(ts, &cache, &warp);
}
}
int retval;
time_init();
+ coverage_clear();
+ coverage_run();
if (*last_wakeup) {
log_poll_interval(*last_wakeup);
}
- coverage_clear();
start = time_msec();
timeout_when = MIN(timeout_when, deadline);
}
}
+/* Makes threads wait on timewarp_seq and be waken up when time is warped.
+ * This function will be no-op unless timeval_dummy_register() is called. */
+void
+timewarp_wait(void)
+{
+ if (timewarp_enabled) {
+ uint64_t *last_seq = last_seq_get();
+
+ *last_seq = seq_read(timewarp_seq);
+ seq_wait(timewarp_seq, *last_seq);
+ }
+}
+
static long long int
timeval_diff_msec(const struct timeval *a, const struct timeval *b)
{
*sum = tmp;
}
+static bool
+is_warped(const struct clock *c)
+{
+ bool warped;
+
+ ovs_mutex_lock(&c->mutex);
+ warped = monotonic_clock.warp.tv_sec || monotonic_clock.warp.tv_nsec;
+ ovs_mutex_unlock(&c->mutex);
+
+ return warped;
+}
+
static void
log_poll_interval(long long int last_wakeup)
{
long long int interval = time_msec() - last_wakeup;
- if (interval >= 1000
- && !monotonic_clock.warp.tv_sec
- && !monotonic_clock.warp.tv_nsec) {
+ if (interval >= 1000 && !is_warped(&monotonic_clock)) {
const struct rusage *last_rusage = get_recent_rusage();
struct rusage rusage;
int argc OVS_UNUSED, const char *argv[] OVS_UNUSED,
void *aux OVS_UNUSED)
{
- ovs_rwlock_wrlock(&monotonic_clock.rwlock);
+ ovs_mutex_lock(&monotonic_clock.mutex);
+ atomic_store(&monotonic_clock.slow_path, true);
monotonic_clock.stopped = true;
xclock_gettime(monotonic_clock.id, &monotonic_clock.cache);
- ovs_rwlock_unlock(&monotonic_clock.rwlock);
+ ovs_mutex_unlock(&monotonic_clock.mutex);
unixctl_command_reply(conn, NULL);
}
ts.tv_sec = msecs / 1000;
ts.tv_nsec = (msecs % 1000) * 1000 * 1000;
- ovs_rwlock_wrlock(&monotonic_clock.rwlock);
+ ovs_mutex_lock(&monotonic_clock.mutex);
+ atomic_store(&monotonic_clock.slow_path, true);
timespec_add(&monotonic_clock.warp, &monotonic_clock.warp, &ts);
- ovs_rwlock_unlock(&monotonic_clock.rwlock);
-
+ ovs_mutex_unlock(&monotonic_clock.mutex);
+ seq_change(timewarp_seq);
unixctl_command_reply(conn, "warped");
}
void
timeval_dummy_register(void)
{
+ timewarp_enabled = true;
unixctl_command_register("time/stop", "", 0, 0, timeval_stop_cb, NULL);
unixctl_command_register("time/warp", "MSECS", 1, 1,
timeval_warp_cb, NULL);