[5/8] qemu-thread: Use futex if available for QemuLockCnt

Commit Message

Akihiko Odaki Dec. 25, 2024, 5:44 a.m. UTC

This unlocks the futex-based implementation of QemuLockCnt to Windows.

Signed-off-by: Akihiko Odaki <[e-mail]>
---
 include/qemu/lockcnt.h | 2 +-
 util/lockcnt.c         | 7 ++++---
 2 files changed, 5 insertions(+), 4 deletions(-)

Patch

diff --git a/include/qemu/lockcnt.h b/include/qemu/lockcnt.h
index f4b62a3f7011..5a2800e3f182 100644
--- a/include/qemu/lockcnt.h
+++ b/include/qemu/lockcnt.h
@@ -17,7 +17,7 @@ 
 typedef struct QemuLockCnt QemuLockCnt;
 
 struct QemuLockCnt {
-#ifndef CONFIG_LINUX
+#ifndef HAVE_FUTEX
     QemuMutex mutex;
 #endif
     unsigned count;
diff --git a/util/lockcnt.c b/util/lockcnt.c
index ca27d8e61a5c..92c9f8ceca88 100644
--- a/util/lockcnt.c
+++ b/util/lockcnt.c
@@ -12,10 +12,11 @@ 
 #include "qemu/atomic.h"
 #include "trace.h"
 
-#ifdef CONFIG_LINUX
-#include "qemu/futex.h"
+#ifdef HAVE_FUTEX
 
-/* On Linux, bits 0-1 are a futex-based lock, bits 2-31 are the counter.
+/*
+ * When futex is available, bits 0-1 are a futex-based lock, bits 2-31 are the
+ * counter.
  * For the mutex algorithm see Ulrich Drepper's "Futexes Are Tricky" (ok,
  * this is not the most relaxing citation I could make...).  It is similar
  * to mutex2 in the paper.