From: Rich Felker <dalias@aerifal.cx>
Date: Wed, 5 Sep 2018 01:28:38 +0000 (-0400)
Subject: in pthread_mutex_trylock, EBUSY out more directly when possible
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=4e4a162d9af283cf71f7310c497672e0c2b8ca3b;p=musl

in pthread_mutex_trylock, EBUSY out more directly when possible

avoid gratuitously setting up and tearing down the robust list pending
slot.
---

diff --git a/src/thread/pthread_mutex_trylock.c b/src/thread/pthread_mutex_trylock.c
index 54876a61..783ca0c4 100644
--- a/src/thread/pthread_mutex_trylock.c
+++ b/src/thread/pthread_mutex_trylock.c
@@ -15,6 +15,7 @@ int __pthread_mutex_trylock_owner(pthread_mutex_t *m)
 		return 0;
 	}
 	if (own == 0x7fffffff) return ENOTRECOVERABLE;
+	if (own && (!(own & 0x40000000) || !(type & 4))) return EBUSY;
 
 	if (m->_m_type & 128) {
 		if (!self->robust_list.off) {
@@ -25,8 +26,7 @@ int __pthread_mutex_trylock_owner(pthread_mutex_t *m)
 		self->robust_list.pending = &m->_m_next;
 	}
 
-	if ((own && (!(own & 0x40000000) || !(type & 4)))
-	    || a_cas(&m->_m_lock, old, tid) != old) {
+	if (a_cas(&m->_m_lock, old, tid) != old) {
 		self->robust_list.pending = 0;
 		return EBUSY;
 	}