atomics: eliminate mb_read/mb_set

qatomic_mb_read and qatomic_mb_set were the very first atomic primitives
introduced for QEMU; their semantics are unclear and they provide a false
sense of safety.

The last use of qatomic_mb_read() has been removed, so delete it.
qatomic_mb_set() instead can survive as an optimized
qatomic_set()+smp_mb(), similar to Linux's smp_store_mb(), but
rename it to qatomic_set_mb() to match the order of the two
operations.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/tests/unit/test-aio-multithread.c b/tests/unit/test-aio-multithread.c
index 80c5d4e2e6..08d4570ccb 100644
--- a/tests/unit/test-aio-multithread.c
+++ b/tests/unit/test-aio-multithread.c
@@ -154,7 +154,7 @@ static coroutine_fn void test_multi_co_schedule_entry(void *opaque)
         n = g_test_rand_int_range(0, NUM_CONTEXTS);
         schedule_next(n);
 
-        qatomic_mb_set(&to_schedule[id], qemu_coroutine_self());
+        qatomic_set_mb(&to_schedule[id], qemu_coroutine_self());
         /* finish_cb can run here.  */
         qemu_coroutine_yield();
         g_assert(to_schedule[id] == NULL);