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/linux-user/signal.c b/linux-user/signal.c
index 8cf51ffecd..73de934c65 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -195,7 +195,7 @@ int block_signals(void)
     sigfillset(&set);
     sigprocmask(SIG_SETMASK, &set, 0);
 
-    return atomic_xchg(&ts->signal_pending, 1);
+    return qatomic_xchg(&ts->signal_pending, 1);
 }
 
 /* Wrapper for sigprocmask function
@@ -688,7 +688,7 @@ int queue_signal(CPUArchState *env, int sig, int si_type,
     ts->sync_signal.info = *info;
     ts->sync_signal.pending = sig;
     /* signal that a new signal is pending */
-    atomic_set(&ts->signal_pending, 1);
+    qatomic_set(&ts->signal_pending, 1);
     return 1; /* indicates that the signal was queued */
 }
 
@@ -1005,7 +1005,7 @@ void process_pending_signals(CPUArchState *cpu_env)
     sigset_t set;
     sigset_t *blocked_set;
 
-    while (atomic_read(&ts->signal_pending)) {
+    while (qatomic_read(&ts->signal_pending)) {
         /* FIXME: This is not threadsafe.  */
         sigfillset(&set);
         sigprocmask(SIG_SETMASK, &set, 0);
@@ -1049,7 +1049,7 @@ void process_pending_signals(CPUArchState *cpu_env)
          * of unblocking might cause us to take another host signal which
          * will set signal_pending again).
          */
-        atomic_set(&ts->signal_pending, 0);
+        qatomic_set(&ts->signal_pending, 0);
         ts->in_sigsuspend = 0;
         set = ts->signal_mask;
         sigdelset(&set, SIGSEGV);