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, 4 insertions, 4 deletions

diff --git a/migration/migration.c b/migration/migration.c
index 58a5452471..d9d1e0b190 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1595,7 +1595,7 @@ void qmp_migrate_start_postcopy(Error **errp)
      * we don't error if migration has finished since that would be racy
      * with issuing this command.
      */
-    atomic_set(&s->start_postcopy, true);
+    qatomic_set(&s->start_postcopy, true);
 }
 
 /* shared migration helpers */
@@ -1603,7 +1603,7 @@ void qmp_migrate_start_postcopy(Error **errp)
 void migrate_set_state(int *state, int old_state, int new_state)
 {
     assert(new_state < MIGRATION_STATUS__MAX);
-    if (atomic_cmpxchg(state, old_state, new_state) == old_state) {
+    if (qatomic_cmpxchg(state, old_state, new_state) == old_state) {
         trace_migrate_set_state(MigrationStatus_str(new_state));
         migrate_generate_event(new_state);
     }
@@ -1954,7 +1954,7 @@ void qmp_migrate_recover(const char *uri, Error **errp)
         return;
     }
 
-    if (atomic_cmpxchg(&mis->postcopy_recover_triggered,
+    if (qatomic_cmpxchg(&mis->postcopy_recover_triggered,
                        false, true) == true) {
         error_setg(errp, "Migrate recovery is triggered already");
         return;
@@ -3329,7 +3329,7 @@ static MigIterateState migration_iteration_run(MigrationState *s)
     if (pending_size && pending_size >= s->threshold_size) {
         /* Still a significant amount to transfer */
         if (!in_postcopy && pend_pre <= s->threshold_size &&
-            atomic_read(&s->start_postcopy)) {
+            qatomic_read(&s->start_postcopy)) {
             if (postcopy_start(s)) {
                 error_report("%s: postcopy failed to start", __func__);
             }