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Stop inlining the struct ucond definition into struct pthread_cond.

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This avoids unneccessary casts and make the calls to _thr_ucond_*()
functions less questionable.

The c_spare field was not included into struct pthread_cond, so the
change modifies libthr ABI for shared condvars.  But since an off-page
does not legitimately contains any other data past the struct
pthread_cond, the change keeps shared condvars from pre- and post-
changed libthr compatible.  Also note that the whole struct ucond was
never copied in or out by kernel.

For private condvars, the privately allocated memory was never exposed
outside libthr.

Sponsored by:	The FreeBSD Foundation
This commit is contained in:
Konstantin Belousov 2016-05-29 19:35:55 +00:00
parent 60404ec965
commit 6180f50bbb
2 changed files with 11 additions and 15 deletions
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22
lib/libthr/thread/thr_cond.c
View File

@ -69,18 +69,18 @@ __weak_reference(_pthread_cond_destroy, pthread_cond_destroy);
__weak_reference(_pthread_cond_signal, pthread_cond_signal);
__weak_reference(_pthread_cond_broadcast, pthread_cond_broadcast);
#define CV_PSHARED(cvp) (((cvp)->__flags & USYNC_PROCESS_SHARED) != 0)
#define CV_PSHARED(cvp) (((cvp)->kcond.c_flags & USYNC_PROCESS_SHARED) != 0)
static void
cond_init_body(struct pthread_cond *cvp, const struct pthread_cond_attr *cattr)
{
if (cattr == NULL) {
cvp->__clock_id = CLOCK_REALTIME;
cvp->kcond.c_clockid = CLOCK_REALTIME;
} else {
if (cattr->c_pshared)
cvp->__flags |= USYNC_PROCESS_SHARED;
cvp->__clock_id = cattr->c_clockid;
cvp->kcond.c_flags |= USYNC_PROCESS_SHARED;
cvp->kcond.c_clockid = cattr->c_clockid;
}
}
@ -205,9 +205,8 @@ cond_wait_kernel(struct pthread_cond *cvp, struct pthread_mutex *mp,
if (cancel)
_thr_cancel_enter2(curthread, 0);
error = _thr_ucond_wait((struct ucond *)&cvp->__has_kern_waiters,
(struct umutex *)&mp->m_lock, abstime, CVWAIT_ABSTIME |
CVWAIT_CLOCKID);
error = _thr_ucond_wait(&cvp->kcond, &mp->m_lock, abstime,
CVWAIT_ABSTIME | CVWAIT_CLOCKID);
if (cancel)
_thr_cancel_leave(curthread, 0);
@ -292,7 +291,7 @@ cond_wait_user(struct pthread_cond *cvp, struct pthread_mutex *mp,
if (cancel)
_thr_cancel_enter2(curthread, 0);
error = _thr_sleep(curthread, cvp->__clock_id, abstime);
error = _thr_sleep(curthread, cvp->kcond.c_clockid, abstime);
if (cancel)
_thr_cancel_leave(curthread, 0);
@ -349,8 +348,7 @@ cond_wait_common(pthread_cond_t *cond, pthread_mutex_t *mutex,
if (curthread->attr.sched_policy != SCHED_OTHER ||
(mp->m_lock.m_flags & (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT |
USYNC_PROCESS_SHARED)) != 0 ||
(cvp->__flags & USYNC_PROCESS_SHARED) != 0)
USYNC_PROCESS_SHARED)) != 0 || CV_PSHARED(cvp))
return (cond_wait_kernel(cvp, mp, abstime, cancel));
else
return (cond_wait_user(cvp, mp, abstime, cancel));
@ -413,7 +411,7 @@ cond_signal_common(pthread_cond_t *cond)
pshared = CV_PSHARED(cvp);
_thr_ucond_signal((struct ucond *)&cvp->__has_kern_waiters);
_thr_ucond_signal(&cvp->kcond);
if (pshared || cvp->__has_user_waiters == 0)
return (0);
@ -496,7 +494,7 @@ cond_broadcast_common(pthread_cond_t *cond)
pshared = CV_PSHARED(cvp);
_thr_ucond_broadcast((struct ucond *)&cvp->__has_kern_waiters);
_thr_ucond_broadcast(&cvp->kcond);
if (pshared || cvp->__has_user_waiters == 0)
return (0);

4
lib/libthr/thread/thr_private.h
View File

@ -190,9 +190,7 @@ struct pthread_mutex_attr {
struct pthread_cond {
__uint32_t __has_user_waiters;
__uint32_t __has_kern_waiters;
__uint32_t __flags;
__uint32_t __clock_id;
struct ucond kcond;
};
struct pthread_cond_attr {