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>

2 files changed, 6 insertions, 6 deletions

diff --git a/hw/hyperv/hyperv.c b/hw/hyperv/hyperv.c
index 4b26db1..cb1074f 100644
--- a/hw/hyperv/hyperv.c
+++ b/hw/hyperv/hyperv.c
@@ -231,7 +231,7 @@ static void sint_msg_bh(void *opaque)
     HvSintRoute *sint_route = opaque;
     HvSintStagedMessage *staged_msg = sint_route->staged_msg;
 
-    if (atomic_read(&staged_msg->state) != HV_STAGED_MSG_POSTED) {
+    if (qatomic_read(&staged_msg->state) != HV_STAGED_MSG_POSTED) {
         /* status nor ready yet (spurious ack from guest?), ignore */
         return;
     }
@@ -240,7 +240,7 @@ static void sint_msg_bh(void *opaque)
     staged_msg->status = 0;
 
     /* staged message processing finished, ready to start over */
-    atomic_set(&staged_msg->state, HV_STAGED_MSG_FREE);
+    qatomic_set(&staged_msg->state, HV_STAGED_MSG_FREE);
     /* drop the reference taken in hyperv_post_msg */
     hyperv_sint_route_unref(sint_route);
 }
@@ -278,7 +278,7 @@ static void cpu_post_msg(CPUState *cs, run_on_cpu_data data)
     memory_region_set_dirty(&synic->msg_page_mr, 0, sizeof(*synic->msg_page));
 
 posted:
-    atomic_set(&staged_msg->state, HV_STAGED_MSG_POSTED);
+    qatomic_set(&staged_msg->state, HV_STAGED_MSG_POSTED);
     /*
      * Notify the msg originator of the progress made; if the slot was busy we
      * set msg_pending flag in it so it will be the guest who will do EOM and
@@ -301,7 +301,7 @@ int hyperv_post_msg(HvSintRoute *sint_route, struct hyperv_message *src_msg)
     assert(staged_msg);
 
     /* grab the staging area */
-    if (atomic_cmpxchg(&staged_msg->state, HV_STAGED_MSG_FREE,
+    if (qatomic_cmpxchg(&staged_msg->state, HV_STAGED_MSG_FREE,
                        HV_STAGED_MSG_BUSY) != HV_STAGED_MSG_FREE) {
         return -EAGAIN;
     }
@@ -351,7 +351,7 @@ int hyperv_set_event_flag(HvSintRoute *sint_route, unsigned eventno)
     set_mask = BIT_MASK(eventno);
     flags = synic->event_page->slot[sint_route->sint].flags;
 
-    if ((atomic_fetch_or(&flags[set_idx], set_mask) & set_mask) != set_mask) {
+    if ((qatomic_fetch_or(&flags[set_idx], set_mask) & set_mask) != set_mask) {
         memory_region_set_dirty(&synic->event_page_mr, 0,
                                 sizeof(*synic->event_page));
         ret = hyperv_sint_route_set_sint(sint_route);
diff --git a/hw/hyperv/vmbus.c b/hw/hyperv/vmbus.c
index 6ef895b..896e981 100644
--- a/hw/hyperv/vmbus.c
+++ b/hw/hyperv/vmbus.c
@@ -747,7 +747,7 @@ static int vmbus_channel_notify_guest(VMBusChannel *chan)
 
     idx = BIT_WORD(chan->id);
     mask = BIT_MASK(chan->id);
-    if ((atomic_fetch_or(&int_map[idx], mask) & mask) != mask) {
+    if ((qatomic_fetch_or(&int_map[idx], mask) & mask) != mask) {
         res = hyperv_sint_route_set_sint(chan->notify_route);
         dirty = len;
     }