minor optimization to pthread_spin_trylock
authorRich Felker <dalias@aerifal.cx>
Wed, 22 Apr 2015 07:24:37 +0000 (03:24 -0400)
committerRich Felker <dalias@aerifal.cx>
Wed, 22 Apr 2015 07:24:37 +0000 (03:24 -0400)
commitafbcac6826988d12d9a874359cab735049c17500
tree61a1f9e9066c22003337266d5847079ede7067d5
parent7b1fb0c526936873a260e860ce3bca82113c3d4c
minor optimization to pthread_spin_trylock

use CAS instead of swap since it's lighter for most archs, and keep
EBUSY in the lock value so that the old value obtained by CAS can be
used directly as the return value for pthread_spin_trylock.
src/thread/pthread_spin_lock.c
src/thread/pthread_spin_trylock.c