diff options
Diffstat (limited to 'Documentation/admin-guide/cpu-load.rst')
| -rw-r--r-- | Documentation/admin-guide/cpu-load.rst | 63 |
1 files changed, 33 insertions, 30 deletions
diff --git a/Documentation/admin-guide/cpu-load.rst b/Documentation/admin-guide/cpu-load.rst index ebdecf864080..f3ada90e9ca8 100644 --- a/Documentation/admin-guide/cpu-load.rst +++ b/Documentation/admin-guide/cpu-load.rst @@ -61,43 +61,46 @@ will lead to quite erratic information inside ``/proc/stat``:: static volatile sig_atomic_t stop; - static void sighandler (int signr) + static void sighandler(int signr) { - (void) signr; - stop = 1; + (void) signr; + stop = 1; } + static unsigned long hog (unsigned long niters) { - stop = 0; - while (!stop && --niters); - return niters; + stop = 0; + while (!stop && --niters); + return niters; } + int main (void) { - int i; - struct itimerval it = { .it_interval = { .tv_sec = 0, .tv_usec = 1 }, - .it_value = { .tv_sec = 0, .tv_usec = 1 } }; - sigset_t set; - unsigned long v[HIST]; - double tmp = 0.0; - unsigned long n; - signal (SIGALRM, &sighandler); - setitimer (ITIMER_REAL, &it, NULL); - - hog (ULONG_MAX); - for (i = 0; i < HIST; ++i) v[i] = ULONG_MAX - hog (ULONG_MAX); - for (i = 0; i < HIST; ++i) tmp += v[i]; - tmp /= HIST; - n = tmp - (tmp / 3.0); - - sigemptyset (&set); - sigaddset (&set, SIGALRM); - - for (;;) { - hog (n); - sigwait (&set, &i); - } - return 0; + int i; + struct itimerval it = { + .it_interval = { .tv_sec = 0, .tv_usec = 1 }, + .it_value = { .tv_sec = 0, .tv_usec = 1 } }; + sigset_t set; + unsigned long v[HIST]; + double tmp = 0.0; + unsigned long n; + signal(SIGALRM, &sighandler); + setitimer(ITIMER_REAL, &it, NULL); + + hog (ULONG_MAX); + for (i = 0; i < HIST; ++i) v[i] = ULONG_MAX - hog(ULONG_MAX); + for (i = 0; i < HIST; ++i) tmp += v[i]; + tmp /= HIST; + n = tmp - (tmp / 3.0); + + sigemptyset(&set); + sigaddset(&set, SIGALRM); + + for (;;) { + hog(n); + sigwait(&set, &i); + } + return 0; } |