#include <errno.h>
#include <poll.h>
#include <signal.h>
+#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <unistd.h>
#include "coverage.h"
+#include "dummy.h"
#include "fatal-signal.h"
#include "signals.h"
+#include "unixctl.h"
#include "util.h"
#include "vlog.h"
static struct timespec wall_time;
static struct timespec monotonic_time;
+/* Fixed monotonic time offset, for use by unit tests. */
+static struct timespec warp_offset;
+
/* Time at which to die with SIGALRM (if not TIME_MIN). */
static time_t deadline = TIME_MIN;
static time_t time_add(time_t, time_t);
static void block_sigalrm(sigset_t *);
static void unblock_sigalrm(const sigset_t *);
-static void log_poll_interval(long long int last_wakeup,
- const struct rusage *last_rusage);
+static void log_poll_interval(long long int last_wakeup);
+static struct rusage *get_recent_rusage(void);
+static void refresh_rusage(void);
+static void timespec_add(struct timespec *sum,
+ const struct timespec *a, const struct timespec *b);
/* Initializes the timetracking module.
*
refresh_wall_if_ticked();
monotonic_time = wall_time;
}
+ timespec_add(&monotonic_time, &monotonic_time, &warp_offset);
monotonic_tick = false;
}
}
/* Like poll(), except:
+ *
+ * - The timeout is specified as an absolute time, as defined by
+ * time_msec(), instead of a duration.
*
* - On error, returns a negative error code (instead of setting errno).
*
* - If interrupted by a signal, retries automatically until the original
- * 'timeout' expires. (Because of this property, this function will
+ * timeout is reached. (Because of this property, this function will
* never return -EINTR.)
*
* - As a side effect, refreshes the current time (like time_refresh()).
- */
+ *
+ * Stores the number of milliseconds elapsed during poll in '*elapsed'. */
int
-time_poll(struct pollfd *pollfds, int n_pollfds, int timeout)
+time_poll(struct pollfd *pollfds, int n_pollfds, long long int timeout_when,
+ int *elapsed)
{
static long long int last_wakeup;
- static struct rusage last_rusage;
long long int start;
sigset_t oldsigs;
bool blocked;
int retval;
time_refresh();
- log_poll_interval(last_wakeup, &last_rusage);
+ log_poll_interval(last_wakeup);
coverage_clear();
start = time_msec();
blocked = false;
for (;;) {
+ long long int now = time_msec();
int time_left;
- if (timeout > 0) {
- long long int elapsed = time_msec() - start;
- time_left = timeout >= elapsed ? timeout - elapsed : 0;
+
+ if (now >= timeout_when) {
+ time_left = 0;
+ } else if ((unsigned long long int) timeout_when - now > INT_MAX) {
+ time_left = INT_MAX;
} else {
- time_left = timeout;
+ time_left = timeout_when - now;
}
retval = poll(pollfds, n_pollfds, time_left);
unblock_sigalrm(&oldsigs);
}
last_wakeup = time_msec();
- getrusage(RUSAGE_SELF, &last_rusage);
+ refresh_rusage();
+ *elapsed = last_wakeup - start;
return retval;
}
}
static void
-log_poll_interval(long long int last_wakeup, const struct rusage *last_rusage)
+timespec_add(struct timespec *sum,
+ const struct timespec *a,
+ const struct timespec *b)
+{
+ struct timespec tmp;
+
+ tmp.tv_sec = a->tv_sec + b->tv_sec;
+ tmp.tv_nsec = a->tv_nsec + b->tv_nsec;
+ if (tmp.tv_nsec >= 1000 * 1000 * 1000) {
+ tmp.tv_nsec -= 1000 * 1000 * 1000;
+ tmp.tv_sec++;
+ }
+
+ *sum = tmp;
+}
+
+static void
+log_poll_interval(long long int last_wakeup)
{
static unsigned int mean_interval; /* In 16ths of a millisecond. */
static unsigned int n_samples;
/* Warn if we took too much time between polls: at least 50 ms and at least
* 8X the mean interval. */
if (n_samples > 10 && interval > mean_interval * 8 && interval > 50 * 16) {
+ const struct rusage *last_rusage = get_recent_rusage();
struct rusage rusage;
getrusage(RUSAGE_SELF, &rusage);
mean_interval = interval;
}
}
+\f
+/* CPU usage tracking. */
+
+struct cpu_usage {
+ long long int when; /* Time that this sample was taken. */
+ 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;
+
+static struct rusage *
+get_recent_rusage(void)
+{
+ return &recent_rusage;
+}
+
+static void
+refresh_rusage(void)
+{
+ long long int now;
+
+ now = time_msec();
+ getrusage(RUSAGE_SELF, &recent_rusage);
+
+ 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;
+ }
+ }
+}
+
+/* Returns an estimate of this process's CPU usage, as a percentage, over the
+ * past few seconds of wall-clock time. Returns -1 if no estimate is available
+ * (which will happen if the process has not been running long enough to have
+ * an estimate, and can happen for other reasons as well). */
+int
+get_cpu_usage(void)
+{
+ return cpu_usage;
+}
+\f
+/* Unixctl interface. */
+
+static void
+timeval_warp_cb(struct unixctl_conn *conn,
+ int argc OVS_UNUSED, const char *argv[], void *aux OVS_UNUSED)
+{
+ struct timespec ts;
+ int msecs;
+
+ msecs = atoi(argv[1]);
+ if (msecs <= 0) {
+ unixctl_command_reply(conn, 501, "invalid MSECS");
+ return;
+ }
+
+ ts.tv_sec = msecs / 1000;
+ ts.tv_nsec = (msecs % 1000) * 1000 * 1000;
+ timespec_add(&warp_offset, &warp_offset, &ts);
+ unixctl_command_reply(conn, 200, "warped");
+}
+
+void
+timeval_dummy_register(void)
+{
+ unixctl_command_register("time/warp", "MSECS", 1, 1,
+ timeval_warp_cb, NULL);
+}
projects / openvswitch / blobdiff