diff options
Diffstat (limited to 'lib/libpthread/thread/thr_concurrency.c')
| -rw-r--r-- | lib/libpthread/thread/thr_concurrency.c | 82 |
1 files changed, 54 insertions, 28 deletions
diff --git a/lib/libpthread/thread/thr_concurrency.c b/lib/libpthread/thread/thr_concurrency.c index 694255a..e1d41e3 100644 --- a/lib/libpthread/thread/thr_concurrency.c +++ b/lib/libpthread/thread/thr_concurrency.c @@ -78,7 +78,7 @@ int _thr_setconcurrency(int new_level) { struct pthread *curthread; - struct kse *newkse; + struct kse *newkse, *kse; kse_critical_t crit; int kse_count; int i; @@ -88,37 +88,63 @@ _thr_setconcurrency(int new_level) curthread = _get_curthread(); /* Race condition, but so what. */ kse_count = _kse_initial->k_kseg->kg_ksecount; - for (i = kse_count; i < new_level; i++) { - newkse = _kse_alloc(curthread, 0); - if (newkse == NULL) { - DBG_MSG("Can't alloc new KSE.\n"); - ret = EAGAIN; - break; - } - newkse->k_kseg = _kse_initial->k_kseg; - newkse->k_schedq = _kse_initial->k_schedq; - newkse->k_curthread = NULL; - crit = _kse_critical_enter(); - KSE_SCHED_LOCK(curthread->kse, newkse->k_kseg); - TAILQ_INSERT_TAIL(&newkse->k_kseg->kg_kseq, - newkse, k_kgqe); - newkse->k_kseg->kg_ksecount++; - newkse->k_flags |= KF_STARTED; - KSE_SCHED_UNLOCK(curthread->kse, newkse->k_kseg); - if (kse_create(&newkse->k_kcb->kcb_kmbx, 0) != 0) { + if (new_level > kse_count) { + for (i = kse_count; i < new_level; i++) { + newkse = _kse_alloc(curthread, 0); + if (newkse == NULL) { + DBG_MSG("Can't alloc new KSE.\n"); + ret = EAGAIN; + break; + } + newkse->k_kseg = _kse_initial->k_kseg; + newkse->k_schedq = _kse_initial->k_schedq; + newkse->k_curthread = NULL; + crit = _kse_critical_enter(); KSE_SCHED_LOCK(curthread->kse, newkse->k_kseg); - TAILQ_REMOVE(&newkse->k_kseg->kg_kseq, + TAILQ_INSERT_TAIL(&newkse->k_kseg->kg_kseq, newkse, k_kgqe); - newkse->k_kseg->kg_ksecount--; + newkse->k_kseg->kg_ksecount++; + newkse->k_flags |= KF_STARTED; KSE_SCHED_UNLOCK(curthread->kse, newkse->k_kseg); - _kse_critical_leave(crit); - _kse_free(curthread, newkse); - DBG_MSG("kse_create syscall failed.\n"); - ret = EAGAIN; - break; - } else { - _kse_critical_leave(crit); + if (kse_create(&newkse->k_kcb->kcb_kmbx, 0) != 0) { + KSE_SCHED_LOCK(curthread->kse, newkse->k_kseg); + TAILQ_REMOVE(&newkse->k_kseg->kg_kseq, + newkse, k_kgqe); + newkse->k_kseg->kg_ksecount--; + KSE_SCHED_UNLOCK(curthread->kse, + newkse->k_kseg); + _kse_critical_leave(crit); + _kse_free(curthread, newkse); + DBG_MSG("kse_create syscall failed.\n"); + ret = EAGAIN; + break; + } else { + _kse_critical_leave(crit); + } + } + } else if (new_level < kse_count) { + kse_count = 0; + crit = _kse_critical_enter(); + KSE_SCHED_LOCK(curthread->kse, _kse_initial->k_kseg); + /* Count the number of active KSEs */ + TAILQ_FOREACH(kse, &_kse_initial->k_kseg->kg_kseq, k_kgqe) { + if ((kse->k_flags & KF_TERMINATED) == 0) + kse_count++; + } + /* Reduce the number of active KSEs appropriately. */ + kse = TAILQ_FIRST(&_kse_initial->k_kseg->kg_kseq); + while ((kse != NULL) && (kse_count > new_level)) { + if ((kse != _kse_initial) && + ((kse->k_flags & KF_TERMINATED) == 0)) { + kse->k_flags |= KF_TERMINATED; + kse_count--; + /* Wakup the KSE in case it is idle. */ + kse_wakeup(&kse->k_kcb->kcb_kmbx); + } + kse = TAILQ_NEXT(kse, k_kgqe); } + KSE_SCHED_UNLOCK(curthread->kse, _kse_initial->k_kseg); + _kse_critical_leave(crit); } return (ret); } |
