[Qemu-devel] [PATCH] posix-aio: don't set aiocb->ret/active outside critical section

[Jim Meyering]

Move code that sets aiocb->ret and aiocb->active into critical section.
All other accesses are lock-guarded.  Spotted by coverity.

Signed-off-by: Jim Meyering <address@hidden>
---
I've included enough context to show one of the
guarded uses in the following function.

 posix-aio-compat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/posix-aio-compat.c b/posix-aio-compat.c
index 68361f5..45511d4 100644
--- a/posix-aio-compat.c
+++ b/posix-aio-compat.c
@@ -421,37 +421,37 @@ static void spawn_thread(void)
 {
     cur_threads++;
     new_threads++;
     /* If there are threads being created, they will spawn new workers, so
      * we don't spend time creating many threads in a loop holding a mutex or
      * starving the current vcpu.
      *
      * If there are no idle threads, ask the main thread to create one, so we
      * inherit the correct affinity instead of the vcpu affinity.
      */
     if (!pending_threads) {
         qemu_bh_schedule(new_thread_bh);
     }
 }

 static void qemu_paio_submit(struct qemu_paiocb *aiocb)
 {
+    mutex_lock(&lock);
     aiocb->ret = -EINPROGRESS;
     aiocb->active = 0;
-    mutex_lock(&lock);
     if (idle_threads == 0 && cur_threads < max_threads)
         spawn_thread();
     QTAILQ_INSERT_TAIL(&request_list, aiocb, node);
     mutex_unlock(&lock);
     cond_signal(&cond);
 }

 static ssize_t qemu_paio_return(struct qemu_paiocb *aiocb)
 {
     ssize_t ret;

     mutex_lock(&lock);
     ret = aiocb->ret;
     mutex_unlock(&lock);

     return ret;
 }
--
1.7.10.2.484.gcd07cc5