chrt: follow nice setting, prefer sched_setscheduler()
* do not reset 'nice' setting by sched_setattr(), if 'nice' setting is not zero then chrt ends with EPERM for non-root users: $ renice -n 5 -p $$; chrt -v -b 0 date 12475 (process ID) old priority 0, new priority 5 chrt: failed to set pid 0's policy: Operation not permitted * it seems more elegant to always use old sched_setscheduler() API for non-deadline policies; in this case we do not need getpriority() to keep 'nice' unchanged. Addresses: https://github.com/karelzak/util-linux/issues/359 Signed-off-by: Karel Zak <kzak@redhat.com>
This commit is contained in:
parent
b5a58919a9
commit
88b60f0bde
|
@ -26,6 +26,8 @@
|
|||
#include <unistd.h>
|
||||
#include <getopt.h>
|
||||
#include <errno.h>
|
||||
#include <sys/time.h>
|
||||
#include <sys/resource.h>
|
||||
|
||||
#include "c.h"
|
||||
#include "nls.h"
|
||||
|
@ -340,6 +342,7 @@ static int set_sched_one_by_setscheduler(struct chrt_ctl *ctl, pid_t pid)
|
|||
struct sched_param sp = { .sched_priority = ctl->priority };
|
||||
int policy = ctl->policy;
|
||||
|
||||
errno = 0;
|
||||
# ifdef SCHED_RESET_ON_FORK
|
||||
if (ctl->reset_on_fork)
|
||||
policy |= SCHED_RESET_ON_FORK;
|
||||
|
@ -357,29 +360,28 @@ static int set_sched_one(struct chrt_ctl *ctl, pid_t pid)
|
|||
#else /* !HAVE_SCHED_SETATTR */
|
||||
static int set_sched_one(struct chrt_ctl *ctl, pid_t pid)
|
||||
{
|
||||
struct sched_attr sa = { .size = sizeof(struct sched_attr) };
|
||||
|
||||
/* old API is good enough for non-deadline */
|
||||
if (ctl->policy != SCHED_DEADLINE)
|
||||
return set_sched_one_by_setscheduler(ctl, pid);
|
||||
|
||||
/* no changeed by chrt, follow the current setting */
|
||||
sa.sched_nice = getpriority(PRIO_PROCESS, pid);
|
||||
|
||||
/* use main() to check if the setting makes sense */
|
||||
struct sched_attr sa = {
|
||||
.size = sizeof(struct sched_attr),
|
||||
.sched_policy = ctl->policy,
|
||||
.sched_priority = ctl->priority,
|
||||
.sched_runtime = ctl->runtime,
|
||||
.sched_period = ctl->period,
|
||||
.sched_deadline = ctl->deadline
|
||||
};
|
||||
int rc;
|
||||
sa.sched_policy = ctl->policy;
|
||||
sa.sched_priority = ctl->priority;
|
||||
sa.sched_runtime = ctl->runtime;
|
||||
sa.sched_period = ctl->period;
|
||||
sa.sched_deadline = ctl->deadline;
|
||||
|
||||
# ifdef SCHED_RESET_ON_FORK
|
||||
if (ctl->reset_on_fork)
|
||||
sa.sched_flags |= SCHED_RESET_ON_FORK;
|
||||
# endif
|
||||
errno = 0;
|
||||
rc = sched_setattr(pid, &sa, 0);
|
||||
|
||||
if (rc != 0 && errno == ENOSYS && ctl->policy != SCHED_DEADLINE)
|
||||
/* fallback -- build with new kernel/libc, but executed on old kernels */
|
||||
rc = set_sched_one_by_setscheduler(ctl, pid);
|
||||
|
||||
return rc;
|
||||
return sched_setattr(pid, &sa, 0);
|
||||
}
|
||||
#endif /* HAVE_SCHED_SETATTR */
|
||||
|
||||
|
|
Loading…
Reference in New Issue