diff options
author | Alex Wang <alexw@nicira.com> | 2013-10-09 04:30:36 +0000 |
---|---|---|
committer | Ethan Jackson <ethan@nicira.com> | 2013-10-08 17:57:58 -0700 |
commit | 53d98a1e9c8c2e5ea2bde30d3461c1d5bfbbfa97 (patch) | |
tree | 556db498301c653bf190f7ab81998373a80553c1 /lib | |
parent | 47aaca882310cc40eff962652529b1bfcea6b431 (diff) | |
download | openvswitch-53d98a1e9c8c2e5ea2bde30d3461c1d5bfbbfa97.tar.gz |
timeval: Wake up all threads when time is warped.
This commit makes the main thread wake up all other threads when time is
warped.
Signed-off-by: Alex Wang <alexw@nicira.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/poll-loop.c | 1 | ||||
-rw-r--r-- | lib/timeval.c | 26 | ||||
-rw-r--r-- | lib/timeval.h | 2 |
3 files changed, 28 insertions, 1 deletions
diff --git a/lib/poll-loop.c b/lib/poll-loop.c index 4eb118701..5e3618bb9 100644 --- a/lib/poll-loop.c +++ b/lib/poll-loop.c @@ -226,6 +226,7 @@ poll_block(void) COVERAGE_INC(poll_zero_timeout); } + timewarp_wait(); retval = time_poll(loop->pollfds, loop->n_waiters, loop->timeout_when, &elapsed); if (retval < 0) { diff --git a/lib/timeval.c b/lib/timeval.c index 64ae845a1..dbfcdf58a 100644 --- a/lib/timeval.c +++ b/lib/timeval.c @@ -33,6 +33,7 @@ #include "hmap.h" #include "ovs-thread.h" #include "signals.h" +#include "seq.h" #include "unixctl.h" #include "util.h" #include "vlog.h" @@ -57,6 +58,14 @@ static struct clock wall_clock; /* CLOCK_REALTIME. */ /* 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; @@ -79,6 +88,7 @@ init_clock(struct clock *c, clockid_t id) ovs_mutex_init(&c->mutex); atomic_init(&c->slow_path, false); xclock_gettime(c->id, &c->cache); + timewarp_seq = seq_create(); } static void @@ -313,6 +323,19 @@ xclock_gettime(clock_t id, struct timespec *ts) } } +/* 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) { @@ -511,13 +534,14 @@ timeval_warp_cb(struct unixctl_conn *conn, atomic_store(&monotonic_clock.slow_path, true); timespec_add(&monotonic_clock.warp, &monotonic_clock.warp, &ts); 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); diff --git a/lib/timeval.h b/lib/timeval.h index 99b3af04c..1bbfd5cd1 100644 --- a/lib/timeval.h +++ b/lib/timeval.h @@ -69,6 +69,8 @@ int get_cpu_usage(void); long long int time_boot_msec(void); +void timewarp_wait(void); + #ifdef __cplusplus } #endif |