diff options
| author | Bernard Xiong <[email protected]> | 2013-03-30 08:16:45 +0800 |
|---|---|---|
| committer | Bernard Xiong <[email protected]> | 2013-03-30 08:16:45 +0800 |
| commit | 512b6ee996ff059e68f02e46fdc8fe8c6f52507a (patch) | |
| tree | 957ca19d2e00761178fdef3c6a84f8731f52d601 | |
| parent | 608074deafecc96c26e219548a74e73f1f594b6d (diff) | |
| parent | 43f59ee2feb56ba599964e1d89fb9d33e57f32aa (diff) | |
Merge branch 'master' of https://github.com/RT-Thread/rt-thread
| -rw-r--r-- | .gitignore | 1 | ||||
| -rw-r--r-- | components/pthreads/pthread.h | 6 | ||||
| -rw-r--r-- | components/pthreads/pthread_rwlock.c | 12 |
3 files changed, 14 insertions, 5 deletions
diff --git a/.gitignore b/.gitignore index e37699b164..9e2a6e8fc5 100644 --- a/.gitignore +++ b/.gitignore @@ -10,3 +10,4 @@ *.idb *.ilk build +*~ diff --git a/components/pthreads/pthread.h b/components/pthreads/pthread.h index fa56219224..6a87c026f6 100644 --- a/components/pthreads/pthread.h +++ b/components/pthreads/pthread.h @@ -104,9 +104,9 @@ struct pthread_rwlock pthread_cond_t rw_condreaders; /* for reader threads waiting */ pthread_cond_t rw_condwriters; /* for writer threads waiting */ - int rw_nwaitreaders; /* the number waiting */ - int rw_nwaitwriters; /* the number waiting */ - int rw_refcount; + int rw_nwaitreaders; /* the number of reader threads waiting */ + int rw_nwaitwriters; /* the number of writer threads waiting */ + int rw_refcount; /* 0: unlocked, -1: locked by writer, > 0 locked by n readers */ }; typedef struct pthread_rwlock pthread_rwlock_t; diff --git a/components/pthreads/pthread_rwlock.c b/components/pthreads/pthread_rwlock.c index 3db0ecc662..b694cb09ff 100644 --- a/components/pthreads/pthread_rwlock.c +++ b/components/pthreads/pthread_rwlock.c @@ -112,9 +112,11 @@ int pthread_rwlock_rdlock (pthread_rwlock_t *rwlock) while (rwlock->rw_refcount < 0 || rwlock->rw_nwaitwriters > 0) { rwlock->rw_nwaitreaders++; + /* rw_mutex will be released when waiting for rw_condreaders */ result = pthread_cond_wait(&rwlock->rw_condreaders, &rwlock->rw_mutex); + /* rw_mutex should have been taken again when returned from waiting */ rwlock->rw_nwaitreaders--; - if (result != 0) + if (result != 0) /* wait error */ break; } @@ -160,7 +162,9 @@ int pthread_rwlock_timedrdlock (pthread_rwlock_t * rwlock, const struct timespec while (rwlock->rw_refcount < 0 || rwlock->rw_nwaitwriters > 0) { rwlock->rw_nwaitreaders++; + /* rw_mutex will be released when waiting for rw_condreaders */ result = pthread_cond_timedwait(&rwlock->rw_condreaders, &rwlock->rw_mutex, abstime); + /* rw_mutex should have been taken again when returned from waiting */ rwlock->rw_nwaitreaders--; if (result != 0) break; @@ -187,7 +191,9 @@ int pthread_rwlock_timedwrlock (pthread_rwlock_t *rwlock, const struct timespec while (rwlock->rw_refcount != 0) { rwlock->rw_nwaitwriters++; + /* rw_mutex will be released when waiting for rw_condwriters */ result = pthread_cond_timedwait(&rwlock->rw_condwriters, &rwlock->rw_mutex, abstime); + /* rw_mutex should have been taken again when returned from waiting */ rwlock->rw_nwaitwriters--; if (result != 0) break; @@ -233,7 +239,7 @@ int pthread_rwlock_unlock (pthread_rwlock_t *rwlock) if (rwlock->rw_refcount > 0) rwlock->rw_refcount--; /* releasing a reader */ else if (rwlock->rw_refcount == -1) - rwlock->rw_refcount = 0; /* releasing a reader */ + rwlock->rw_refcount = 0; /* releasing a writer */ /* give preference to waiting writers over waiting readers */ if (rwlock->rw_nwaitwriters > 0) @@ -264,7 +270,9 @@ int pthread_rwlock_wrlock (pthread_rwlock_t *rwlock) while (rwlock->rw_refcount != 0) { rwlock->rw_nwaitwriters++; + /* rw_mutex will be released when waiting for rw_condwriters */ result = pthread_cond_wait(&rwlock->rw_condwriters, &rwlock->rw_mutex); + /* rw_mutex should have been taken again when returned from waiting */ rwlock->rw_nwaitwriters--; if (result != 0) break; |