qemu/atomic.h: rename atomic_ to qatomic_

clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:

  $ CC=clang CXX=clang++ ./configure ... && make
  ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)

Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.

This patch was generated using:

  $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
    sort -u >/tmp/changed_identifiers
  $ for identifier in $(</tmp/changed_identifiers); do
        sed -i "s%\<$identifier\>%q$identifier%g" \
            $(git grep -I -l "\<$identifier\>")
    done

I manually fixed line-wrap issues and misaligned rST tables.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>

1 files changed, 7 insertions, 7 deletions

diff --git a/tests/atomic64-bench.c b/tests/atomic64-bench.c
index 121a8c14f4..e474753d34 100644
--- a/tests/atomic64-bench.c
+++ b/tests/atomic64-bench.c
@@ -56,17 +56,17 @@ static void *thread_func(void *arg)
 {
     struct thread_info *info = arg;
 
-    atomic_inc(&n_ready_threads);
-    while (!atomic_read(&test_start)) {
+    qatomic_inc(&n_ready_threads);
+    while (!qatomic_read(&test_start)) {
         cpu_relax();
     }
 
-    while (!atomic_read(&test_stop)) {
+    while (!qatomic_read(&test_stop)) {
         unsigned int index;
 
         info->r = xorshift64star(info->r);
         index = info->r & (range - 1);
-        atomic_read_i64(&counts[index].i64);
+        qatomic_read_i64(&counts[index].i64);
         info->accesses++;
     }
     return NULL;
@@ -76,13 +76,13 @@ static void run_test(void)
 {
     unsigned int i;
 
-    while (atomic_read(&n_ready_threads) != n_threads) {
+    while (qatomic_read(&n_ready_threads) != n_threads) {
         cpu_relax();
     }
 
-    atomic_set(&test_start, true);
+    qatomic_set(&test_start, true);
     g_usleep(duration * G_USEC_PER_SEC);
-    atomic_set(&test_stop, true);
+    qatomic_set(&test_stop, true);
 
     for (i = 0; i < n_threads; i++) {
         qemu_thread_join(&threads[i]);