diff options
Diffstat (limited to 'src/cyclictest/cyclictest.c')
| -rw-r--r-- | src/cyclictest/cyclictest.c | 76 |
1 files changed, 75 insertions, 1 deletions
diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c index 880f42c..11b6cea 100644 --- a/src/cyclictest/cyclictest.c +++ b/src/cyclictest/cyclictest.c @@ -31,6 +31,7 @@ #include <sys/sysinfo.h> #include <sys/types.h> #include <sys/time.h> +#include <sys/resource.h> #include <sys/utsname.h> #include <sys/mman.h> #include "rt_numa.h" @@ -589,6 +590,79 @@ parse_time_string(char *val) } /* + * Raise the soft priority limit up to prio, if that is less than or equal + * to the hard limit + * if a call fails, return the error + * if successful return 0 + * if fails, return -1 +*/ +static int raise_soft_prio(int policy, const struct sched_param *param) +{ + int err; + int policy_max; /* max for scheduling policy such as SCHED_FIFO */ + int soft_max; + int hard_max; + int prio; + struct rlimit rlim; + + prio = param->sched_priority; + + policy_max = sched_get_priority_max(policy); + if (policy_max == -1) { + err = errno; + err_msg("WARN: no such policy\n"); + return err; + } + + err = getrlimit(RLIMIT_RTPRIO, &rlim); + if (err) { + err = errno; + err_msg_n(err, "WARN: getrlimit failed\n"); + return err; + } + + soft_max = (rlim.rlim_cur == RLIM_INFINITY) ? policy_max : rlim.rlim_cur; + hard_max = (rlim.rlim_max == RLIM_INFINITY) ? policy_max : rlim.rlim_max; + + if (prio > soft_max && prio <= hard_max) { + rlim.rlim_cur = prio; + err = setrlimit(RLIMIT_RTPRIO, &rlim); + if (err) { + err = errno; + err_msg_n(err, "WARN: setrlimit failed\n"); + /* return err; */ + } + } else { + err = -1; + } + + return err; +} + +/* + * Check the error status of sched_setscheduler + * If an error can be corrected by raising the soft limit priority to + * a priority less than or equal to the hard limit, then do so. + */ +static int setscheduler(pid_t pid, int policy, const struct sched_param *param) +{ + int err = 0; + +try_again: + err = sched_setscheduler(pid, policy, param); + if (err) { + err = errno; + if (err == EPERM) { + int err1; + err1 = raise_soft_prio(policy, param); + if (!err1) goto try_again; + } + } + + return err; +} + +/* * timer thread * * Modes: @@ -646,7 +720,7 @@ void *timerthread(void *param) memset(&schedp, 0, sizeof(schedp)); schedp.sched_priority = par->prio; - if (sched_setscheduler(0, par->policy, &schedp)) + if (setscheduler(0, par->policy, &schedp)) fatal("timerthread%d: failed to set priority to %d\n", par->cpu, par->prio); /* Get current time */ |