Use the new atomic operations interface

Stick to a sequentially consistent model for most atomic operations as it
matches the semantics of the existing code. Each call site will have to be
reevaluated in order to switch to more relaxed accesses where possible.

1 files changed, 5 insertions, 11 deletions

diff --git a/kern/rtmutex.c b/kern/rtmutex.c
index f79f8a8..3f4251f 100644
--- a/kern/rtmutex.c
+++ b/kern/rtmutex.c
@@ -19,23 +19,17 @@
 #include <stdint.h>
 
 #include <kern/assert.h>
+#include <kern/atomic.h>
 #include <kern/rtmutex.h>
 #include <kern/rtmutex_i.h>
 #include <kern/rtmutex_types.h>
 #include <kern/thread.h>
 #include <kern/turnstile.h>
-#include <machine/atomic.h>
 
 static void
 rtmutex_set_contended(struct rtmutex *rtmutex)
 {
-    uintptr_t owner, prev_owner;
-
-    do {
-        owner = rtmutex->owner;
-        prev_owner = atomic_cas_uintptr(&rtmutex->owner, owner,
-                                        owner | RTMUTEX_CONTENDED);
-    } while (prev_owner != owner);
+    atomic_or(&rtmutex->owner, RTMUTEX_CONTENDED, ATOMIC_SEQ_CST);
 }
 
 void
@@ -55,7 +49,7 @@ rtmutex_lock_slow(struct rtmutex *rtmutex)
     bits = RTMUTEX_CONTENDED;
 
     for (;;) {
-        prev_owner = atomic_cas_uintptr(&rtmutex->owner, bits, owner | bits);
+        prev_owner = atomic_cas_seq_cst(&rtmutex->owner, bits, owner | bits);
         assert((prev_owner & bits) == bits);
 
         if (prev_owner == bits) {
@@ -70,7 +64,7 @@ rtmutex_lock_slow(struct rtmutex *rtmutex)
     turnstile_own(turnstile);
 
     if (turnstile_empty(turnstile)) {
-        prev_owner = atomic_swap_uintptr(&rtmutex->owner, owner);
+        prev_owner = atomic_swap_seq_cst(&rtmutex->owner, owner);
         assert(prev_owner == (owner | bits));
     }
 
@@ -95,7 +89,7 @@ rtmutex_unlock_slow(struct rtmutex *rtmutex)
     turnstile = turnstile_acquire(rtmutex);
     assert(turnstile != NULL);
 
-    prev_owner = atomic_swap_uintptr(&rtmutex->owner,
+    prev_owner = atomic_swap_seq_cst(&rtmutex->owner,
                                      RTMUTEX_FORCE_WAIT | RTMUTEX_CONTENDED);
     assert((prev_owner & RTMUTEX_OWNER_MASK) == owner);