mir/openvswitch
2
0
Fork 0
mirror of https://github.com/openvswitch/ovs synced 2025-10-25 15:07:05 +00:00
Code Issues Releases Wiki Activity

timeval: Make CPU usage and wakeup tracking per-thread.

Browse Source 
This should make the "timeval" module thread-safe, except for its
calls into vlog (because vlog is not yet thread-safe).

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Ed Maste <emaste@freebsd.org>
This commit is contained in:
Ben Pfaff
2013-06-25 13:56:40 -07:00
parent 75f9c912f2
commit 4c694ff745
1 changed files with 61 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

87
lib/timeval.c
View File

@@ -63,6 +63,10 @@ static long long int boot_time;
* LLONG_MAX). */
static long long int deadline = LLONG_MAX;
/* Monotonic time, in milliseconds, at which the last call to time_poll() woke
* up. */
DEFINE_PER_THREAD_DATA(long long int, last_wakeup, 0);
static void set_up_timer(void);
static void set_up_signal(int flags);
static void sigalrm_handler(int);
@@ -151,6 +155,7 @@ set_up_timer(void)
void
time_postfork(void)
{
assert_single_threaded();
time_init();
set_up_timer();
}
@@ -288,15 +293,16 @@ int
time_poll(struct pollfd *pollfds, int n_pollfds, long long int timeout_when,
int *elapsed)
{
static long long int last_wakeup = 0;
long long int *last_wakeup = last_wakeup_get();
long long int start;
sigset_t oldsigs;
bool blocked;
int retval;
time_init();
time_refresh();
if (last_wakeup) {
log_poll_interval(last_wakeup);
if (*last_wakeup) {
log_poll_interval(*last_wakeup);
}
coverage_clear();
start = time_msec();
@@ -342,9 +348,9 @@ time_poll(struct pollfd *pollfds, int n_pollfds, long long int timeout_when,
if (blocked) {
unblock_sigalrm(&oldsigs);
}
last_wakeup = time_msec();
*last_wakeup = time_msec();
refresh_rusage();
*elapsed = last_wakeup - start;
*elapsed = *last_wakeup - start;
return retval;
}
@@ -479,37 +485,66 @@ struct cpu_usage {
unsigned long long int cpu; /* Total user+system CPU usage when sampled. */
};
static struct rusage recent_rusage;
static struct cpu_usage older = { LLONG_MIN, 0 };
static struct cpu_usage newer = { LLONG_MIN, 0 };
static int cpu_usage = -1;
struct cpu_tracker {
struct cpu_usage older;
struct cpu_usage newer;
int cpu_usage;
struct rusage recent_rusage;
};
DEFINE_PER_THREAD_MALLOCED_DATA(struct cpu_tracker *, cpu_tracker_var);
static struct cpu_tracker *
get_cpu_tracker(void)
{
struct cpu_tracker *t = cpu_tracker_var_get();
if (!t) {
t = xzalloc(sizeof *t);
t->older.when = LLONG_MIN;
t->newer.when = LLONG_MIN;
cpu_tracker_var_set_unsafe(t);
}
return t;
}
static struct rusage *
get_recent_rusage(void)
{
return &recent_rusage;
return &get_cpu_tracker()->recent_rusage;
}
static int
getrusage_thread(struct rusage *rusage OVS_UNUSED)
{
#ifdef RUSAGE_THREAD
return getrusage(RUSAGE_THREAD, rusage);
#else
errno = EINVAL;
return -1;
#endif
}
static void
refresh_rusage(void)
{
long long int now;
struct cpu_tracker *t = get_cpu_tracker();
struct rusage *recent_rusage = &t->recent_rusage;
now = time_msec();
getrusage(RUSAGE_SELF, &recent_rusage);
if (!getrusage_thread(recent_rusage)) {
long long int now = time_msec();
if (now >= t->newer.when + 3 * 1000) {
t->older = t->newer;
t->newer.when = now;
t->newer.cpu = (timeval_to_msec(&recent_rusage->ru_utime) +
timeval_to_msec(&recent_rusage->ru_stime));
if (now >= newer.when + 3 * 1000) {
older = newer;
newer.when = now;
newer.cpu = (timeval_to_msec(&recent_rusage.ru_utime) +
timeval_to_msec(&recent_rusage.ru_stime));
if (older.when != LLONG_MIN && newer.cpu > older.cpu) {
unsigned int dividend = newer.cpu - older.cpu;
unsigned int divisor = (newer.when - older.when) / 100;
cpu_usage = divisor > 0 ? dividend / divisor : -1;
} else {
cpu_usage = -1;
if (t->older.when != LLONG_MIN && t->newer.cpu > t->older.cpu) {
unsigned int dividend = t->newer.cpu - t->older.cpu;
unsigned int divisor = (t->newer.when - t->older.when) / 100;
t->cpu_usage = divisor > 0 ? dividend / divisor : -1;
} else {
t->cpu_usage = -1;
}
}
}
}
@@ -521,7 +556,7 @@ refresh_rusage(void)
int
get_cpu_usage(void)
{
return cpu_usage;
return get_cpu_tracker()->cpu_usage;
}
/* Unixctl interface. */