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/include/qemu/seqlock.h b/include/qemu/seqlock.h
index 8b6b4ee..ecb7d2c 100644
--- a/include/qemu/seqlock.h
+++ b/include/qemu/seqlock.h
@@ -32,7 +32,7 @@ static inline void seqlock_init(QemuSeqLock *sl)
 /* Lock out other writers and update the count.  */
 static inline void seqlock_write_begin(QemuSeqLock *sl)
 {
-    atomic_set(&sl->sequence, sl->sequence + 1);
+    qatomic_set(&sl->sequence, sl->sequence + 1);
 
     /* Write sequence before updating other fields.  */
     smp_wmb();
@@ -43,7 +43,7 @@ static inline void seqlock_write_end(QemuSeqLock *sl)
     /* Write other fields before finalizing sequence.  */
     smp_wmb();
 
-    atomic_set(&sl->sequence, sl->sequence + 1);
+    qatomic_set(&sl->sequence, sl->sequence + 1);
 }
 
 /* Lock out other writers and update the count.  */
@@ -68,7 +68,7 @@ static inline void seqlock_write_unlock_impl(QemuSeqLock *sl, QemuLockable *lock
 static inline unsigned seqlock_read_begin(const QemuSeqLock *sl)
 {
     /* Always fail if a write is in progress.  */
-    unsigned ret = atomic_read(&sl->sequence);
+    unsigned ret = qatomic_read(&sl->sequence);
 
     /* Read sequence before reading other fields.  */
     smp_rmb();
@@ -79,7 +79,7 @@ static inline int seqlock_read_retry(const QemuSeqLock *sl, unsigned start)
 {
     /* Read other fields before reading final sequence.  */
     smp_rmb();
-    return unlikely(atomic_read(&sl->sequence) != start);
+    return unlikely(qatomic_read(&sl->sequence) != start);
 }
 
 #endif