ref: ee8cd40d871ece1bf971f60308c7c007df391bca
parent: 36002110e45db5e89efe4bd664f1926dced83545
author: Ori Bernstein <ori@eigenstate.org>
date: Thu May 5 18:41:42 EDT 2016
I give up.
OSX gets a spinlock for now.
--- a/lib/thread/bld.proj
+++ b/lib/thread/bld.proj
@@ -16,7 +16,7 @@
# osx impl of thread primitives
#condvar+osx.myr
- #mutex+osx.myr
+ mutex+osx.myr
spawn+osx.myr
start+osx-x64.s
--- /dev/null
+++ b/lib/thread/mutex+osx.myr
@@ -1,0 +1,65 @@
+use std
+use sys
+
+
+use "atomic.use"
+use "common.use"
+
+pkg thread =
+ type mutex = struct
+ _state : uint32
+ ;;
+
+ const mkmtx : (-> mutex)
+ const mtxlock : (mtx : mutex# -> void)
+ const mtxtrylock : (mtx : mutex# -> bool)
+ const mtxunlock : (mtx : mutex# -> void)
+;;
+
+const mkmtx = {+ -> [._state = 0]
+}
+
+/* a shitty spinlock */
+const mtxlock = {mtx+ /* first fast */
+ for var i = 0; i < 1000; i++
+ if xcas(&mtx._state, 0, 1) == 0
+ -> void
+ ;;
+ std.nanosleep(0)
+ ;;
+
+ /* then slower */
+ for var i = 0; i < 1000; i++
+ if xcas(&mtx._state, 0, 1) == 0
+ -> void
+ ;;
+ std.nanosleep(10_000) /* 10 us */
+ ;;
+
+ /* even slower */
+ for var i = 0; i < 1000; i++
+ if xcas(&mtx._state, 0, 1) == 0
+ -> void
+ ;;
+ std.nanosleep(100_000) /* 100 us */
+ ;;
+
+ /* I'm rip van winkle! */
+ while true
+ if xcas(&mtx._state, 0, 1) == 0
+ -> void
+ ;;
+ std.nanosleep(1000_000) /* 1 ms */
+ ;;
+}
+
+const mtxtrylock = {mtx+ -> xcas(&mtx._state, 0, 1) == 0
+}
+
+
+const mtxunlock = {mtx+ xset(&mtx._state, 0)
+}