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, 17 insertions, 17 deletions

diff --git a/util/stats64.c b/util/stats64.c
index 389c365..897613c 100644
--- a/util/stats64.c
+++ b/util/stats64.c
@@ -18,27 +18,27 @@
 static inline void stat64_rdlock(Stat64 *s)
 {
     /* Keep out incoming writers to avoid them starving us. */
-    atomic_add(&s->lock, 2);
+    qatomic_add(&s->lock, 2);
 
     /* If there is a concurrent writer, wait for it.  */
-    while (atomic_read(&s->lock) & 1) {
+    while (qatomic_read(&s->lock) & 1) {
         cpu_relax();
     }
 }
 
 static inline void stat64_rdunlock(Stat64 *s)
 {
-    atomic_sub(&s->lock, 2);
+    qatomic_sub(&s->lock, 2);
 }
 
 static inline bool stat64_wrtrylock(Stat64 *s)
 {
-    return atomic_cmpxchg(&s->lock, 0, 1) == 0;
+    return qatomic_cmpxchg(&s->lock, 0, 1) == 0;
 }
 
 static inline void stat64_wrunlock(Stat64 *s)
 {
-    atomic_dec(&s->lock);
+    qatomic_dec(&s->lock);
 }
 
 uint64_t stat64_get(const Stat64 *s)
@@ -50,8 +50,8 @@ uint64_t stat64_get(const Stat64 *s)
     /* 64-bit writes always take the lock, so we can read in
      * any order.
      */
-    high = atomic_read(&s->high);
-    low = atomic_read(&s->low);
+    high = qatomic_read(&s->high);
+    low = qatomic_read(&s->low);
     stat64_rdunlock((Stat64 *)s);
 
     return ((uint64_t)high << 32) | low;
@@ -70,9 +70,9 @@ bool stat64_add32_carry(Stat64 *s, uint32_t low, uint32_t high)
      * order of our update.  By updating s->low first, we can check
      * whether we have to carry into s->high.
      */
-    old = atomic_fetch_add(&s->low, low);
+    old = qatomic_fetch_add(&s->low, low);
     high += (old + low) < old;
-    atomic_add(&s->high, high);
+    qatomic_add(&s->high, high);
     stat64_wrunlock(s);
     return true;
 }
@@ -87,8 +87,8 @@ bool stat64_min_slow(Stat64 *s, uint64_t value)
         return false;
     }
 
-    high = atomic_read(&s->high);
-    low = atomic_read(&s->low);
+    high = qatomic_read(&s->high);
+    low = qatomic_read(&s->low);
 
     orig = ((uint64_t)high << 32) | low;
     if (value < orig) {
@@ -98,9 +98,9 @@ bool stat64_min_slow(Stat64 *s, uint64_t value)
          * effect on stat64_min is that the slow path may be triggered
          * unnecessarily.
          */
-        atomic_set(&s->low, (uint32_t)value);
+        qatomic_set(&s->low, (uint32_t)value);
         smp_wmb();
-        atomic_set(&s->high, value >> 32);
+        qatomic_set(&s->high, value >> 32);
     }
     stat64_wrunlock(s);
     return true;
@@ -116,8 +116,8 @@ bool stat64_max_slow(Stat64 *s, uint64_t value)
         return false;
     }
 
-    high = atomic_read(&s->high);
-    low = atomic_read(&s->low);
+    high = qatomic_read(&s->high);
+    low = qatomic_read(&s->low);
 
     orig = ((uint64_t)high << 32) | low;
     if (value > orig) {
@@ -127,9 +127,9 @@ bool stat64_max_slow(Stat64 *s, uint64_t value)
          * effect on stat64_max is that the slow path may be triggered
          * unnecessarily.
          */
-        atomic_set(&s->low, (uint32_t)value);
+        qatomic_set(&s->low, (uint32_t)value);
         smp_wmb();
-        atomic_set(&s->high, value >> 32);
+        qatomic_set(&s->high, value >> 32);
     }
     stat64_wrunlock(s);
     return true;