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, 2 insertions, 2 deletions

diff --git a/util/fdmon-epoll.c b/util/fdmon-epoll.c
index fcd989d..e11a8a02 100644
--- a/util/fdmon-epoll.c
+++ b/util/fdmon-epoll.c
@@ -65,7 +65,7 @@ static int fdmon_epoll_wait(AioContext *ctx, AioHandlerList *ready_list,
     struct epoll_event events[128];
 
     /* Fall back while external clients are disabled */
-    if (atomic_read(&ctx->external_disable_cnt)) {
+    if (qatomic_read(&ctx->external_disable_cnt)) {
         return fdmon_poll_ops.wait(ctx, ready_list, timeout);
     }
 
@@ -132,7 +132,7 @@ bool fdmon_epoll_try_upgrade(AioContext *ctx, unsigned npfd)
     }
 
     /* Do not upgrade while external clients are disabled */
-    if (atomic_read(&ctx->external_disable_cnt)) {
+    if (qatomic_read(&ctx->external_disable_cnt)) {
         return false;
     }