Add pthread_rwlockattr_setkind_np and pthread_rwlockattr_getkind_np, the

functions set or get pthread_rwlock type, current supported types are:
   PTHREAD_RWLOCK_PREFER_READER_NP,
   PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP,
   PTHREAD_RWLOCK_PREFER_WRITER_NP,
default is PTHREAD_RWLOCK_PREFER_WRITER_NONCECURSIVE_NP, this maintains
binary compatible with old code.

4 files changed, 50 insertions, 2 deletions

diff --git a/lib/libthr/pthread.map b/lib/libthr/pthread.map
index 5e36239..2d7624e 100644
--- a/lib/libthr/pthread.map
+++ b/lib/libthr/pthread.map
@@ -318,7 +318,9 @@ FBSDprivate_1.0 {
 	_pthread_rwlock_wrlock;
 	_pthread_rwlockattr_destroy;
 	_pthread_rwlockattr_getpshared;
+	_pthread_rwlockattr_getkind_np;
 	_pthread_rwlockattr_init;
+	_pthread_rwlockattr_setkind_np;
 	_pthread_rwlockattr_setpshared;
 	_pthread_self;
 	_pthread_set_name_np;
@@ -403,4 +405,6 @@ FBSD_1.2 {
 	openat;
 	setcontext;
 	swapcontext;
+	pthread_rwlockattr_getkind_np;
+	pthread_rwlockattr_setkind_np;
 };
diff --git a/lib/libthr/thread/thr_private.h b/lib/libthr/thread/thr_private.h
index aa9feef..5d0c301 100644
--- a/lib/libthr/thread/thr_private.h
+++ b/lib/libthr/thread/thr_private.h
@@ -285,11 +285,14 @@ struct pthread_prio {
 
 struct pthread_rwlockattr {
 	int		pshared;
+	int		kind;
 };
 
 struct pthread_rwlock {
 	struct urwlock 	lock;
 	struct pthread	*owner;
+	int	recurse;
+	int	kind;
 };
 
 /*
diff --git a/lib/libthr/thread/thr_rwlock.c b/lib/libthr/thread/thr_rwlock.c
index ebdeae7..20b9b79 100644
--- a/lib/libthr/thread/thr_rwlock.c
+++ b/lib/libthr/thread/thr_rwlock.c
@@ -63,13 +63,19 @@ __weak_reference(_pthread_rwlock_timedwrlock, pthread_rwlock_timedwrlock);
  */
 
 static int
-rwlock_init(pthread_rwlock_t *rwlock, const pthread_rwlockattr_t *attr __unused)
+rwlock_init(pthread_rwlock_t *rwlock, const pthread_rwlockattr_t *attr)
 {
 	pthread_rwlock_t prwlock;
 
 	prwlock = (pthread_rwlock_t)calloc(1, sizeof(struct pthread_rwlock));
 	if (prwlock == NULL)
 		return (ENOMEM);
+	if (attr != NULL)
+		prwlock->kind = (*attr)->kind;
+	else
+		prwlock->kind = PTHREAD_RWLOCK_DEFAULT_NP;
+	if (prwlock->kind == PTHREAD_RWLOCK_PREFER_READER_NP)
+		prwlock->lock.rw_flags |= URWLOCK_PREFER_READER;
 	*rwlock = prwlock;
 	return (0);
 }
@@ -112,7 +118,7 @@ init_static(struct pthread *thread, pthread_rwlock_t *rwlock)
 }
 
 int
-_pthread_rwlock_init (pthread_rwlock_t *rwlock, const pthread_rwlockattr_t *attr)
+_pthread_rwlock_init(pthread_rwlock_t *rwlock, const pthread_rwlockattr_t *attr)
 {
 	*rwlock = NULL;
 	return (rwlock_init(rwlock, attr));
@@ -260,6 +266,14 @@ rwlock_wrlock_common (pthread_rwlock_t *rwlock, const struct timespec *abstime)
 
 	CHECK_AND_INIT_RWLOCK
 
+	if (__predict_false(prwlock->owner == curthread)) {
+		if (__predict_false(
+			prwlock->kind == PTHREAD_RWLOCK_PREFER_WRITER_NP)) {
+			prwlock->recurse++;
+			return (0);
+		}
+	}
+
 	/*
 	 * POSIX said the validity of the abstimeout parameter need
 	 * not be checked if the lock can be immediately acquired.
@@ -335,6 +349,13 @@ _pthread_rwlock_unlock (pthread_rwlock_t *rwlock)
 	if (state & URWLOCK_WRITE_OWNER) {
 		if (__predict_false(prwlock->owner != curthread))
 			return (EPERM);
+		if (__predict_false(
+			prwlock->kind == PTHREAD_RWLOCK_PREFER_WRITER_NP)) {
+			if (prwlock->recurse > 0) {
+				prwlock->recurse--;
+				return (0);
+			}
+		}
 		prwlock->owner = NULL;
 	}
 
diff --git a/lib/libthr/thread/thr_rwlockattr.c b/lib/libthr/thread/thr_rwlockattr.c
index b47d167..edc87d2 100644
--- a/lib/libthr/thread/thr_rwlockattr.c
+++ b/lib/libthr/thread/thr_rwlockattr.c
@@ -36,8 +36,10 @@
 
 __weak_reference(_pthread_rwlockattr_destroy, pthread_rwlockattr_destroy);
 __weak_reference(_pthread_rwlockattr_getpshared, pthread_rwlockattr_getpshared);
+__weak_reference(_pthread_rwlockattr_getkind_np, pthread_rwlockattr_getkind_np);
 __weak_reference(_pthread_rwlockattr_init, pthread_rwlockattr_init);
 __weak_reference(_pthread_rwlockattr_setpshared, pthread_rwlockattr_setpshared);
+__weak_reference(_pthread_rwlockattr_setkind_np, pthread_rwlockattr_setkind_np);
 
 int
 _pthread_rwlockattr_destroy(pthread_rwlockattr_t *rwlockattr)
@@ -98,3 +100,21 @@ _pthread_rwlockattr_setpshared(pthread_rwlockattr_t *rwlockattr, int pshared)
 	return(0);
 }
 
+int
+_pthread_rwlockattr_setkind_np(pthread_rwlockattr_t *attr, int kind)
+{
+	if (kind != PTHREAD_RWLOCK_PREFER_READER_NP ||
+	    kind != PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP ||
+	    kind != PTHREAD_RWLOCK_PREFER_WRITER_NP) {
+		return (EINVAL);
+	}
+	(*attr)->kind = kind;
+	return (0);
+}
+
+int
+_pthread_rwlockattr_getkind_np(const pthread_rwlockattr_t *attr, int *kind)
+{
+	*kind = (*attr)->kind;
+	return (0);
+}