13 files changed, 142 insertions, 112 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index bf62247872..c21d6a2f9e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3061,8 +3061,10 @@ S: Maintained
 F: docs/devel/lockcnt.rst
 F: docs/devel/rcu.rst
 F: include/qemu/rcu*.h
+F: include/qemu/lockcnt.h
 F: tests/unit/rcutorture.c
 F: tests/unit/test-rcu-*.c
+F: util/lockcnt.c
 F: util/rcu.c
 
 Human Monitor (HMP)
diff --git a/accel/accel-blocker.c b/accel/accel-blocker.c
index e083f24aa8..75daaa2911 100644
--- a/accel/accel-blocker.c
+++ b/accel/accel-blocker.c
@@ -25,6 +25,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/lockcnt.h"
 #include "qemu/thread.h"
 #include "qemu/main-loop.h"
 #include "hw/core/cpu.h"
diff --git a/docs/devel/lockcnt.rst b/docs/devel/lockcnt.rst
index 994aeb5715..728594bcea 100644
--- a/docs/devel/lockcnt.rst
+++ b/docs/devel/lockcnt.rst
@@ -175,7 +175,7 @@ three instructions in the critical path, two assignments and a ``smp_wmb()``.
 ``QemuLockCnt`` API
 -------------------
 
-The ``QemuLockCnt`` API is described in ``include/qemu/thread.h``.
+The ``QemuLockCnt`` API is described in ``include/qemu/lockcnt.h``.
 
 
 ``QemuLockCnt`` usage
diff --git a/hw/core/cpu-common.c b/hw/core/cpu-common.c
index 7982ecd39a..09c7903594 100644
--- a/hw/core/cpu-common.c
+++ b/hw/core/cpu-common.c
@@ -24,6 +24,7 @@
 #include "sysemu/hw_accel.h"
 #include "qemu/log.h"
 #include "qemu/main-loop.h"
+#include "qemu/lockcnt.h"
 #include "exec/log.h"
 #include "exec/gdbstub.h"
 #include "sysemu/tcg.h"
diff --git a/include/block/aio.h b/include/block/aio.h
index 4ee81936ed..43883a8a33 100644
--- a/include/block/aio.h
+++ b/include/block/aio.h
@@ -20,6 +20,7 @@
 #include "qemu/coroutine-core.h"
 #include "qemu/queue.h"
 #include "qemu/event_notifier.h"
+#include "qemu/lockcnt.h"
 #include "qemu/thread.h"
 #include "qemu/timer.h"
 #include "block/graph-lock.h"
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
index d21a24c82f..c3ca0babcb 100644
--- a/include/hw/core/cpu.h
+++ b/include/hw/core/cpu.h
@@ -33,6 +33,7 @@
 #include "qemu/bitmap.h"
 #include "qemu/rcu_queue.h"
 #include "qemu/queue.h"
+#include "qemu/lockcnt.h"
 #include "qemu/thread.h"
 #include "qom/object.h"
 
diff --git a/include/qemu/lockcnt.h b/include/qemu/lockcnt.h
new file mode 100644
index 0000000000..2c92ae17c9
--- /dev/null
+++ b/include/qemu/lockcnt.h
@@ -0,0 +1,130 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * QemuLockCnt implementation
+ *
+ * Copyright Red Hat, Inc. 2017
+ *
+ * Author:
+ *   Paolo Bonzini <pbonzini@redhat.com>
+ *
+ */
+
+#ifndef QEMU_LOCKCNT_H
+#define QEMU_LOCKCNT_H
+
+#include "qemu/thread.h"
+
+typedef struct QemuLockCnt QemuLockCnt;
+
+struct QemuLockCnt {
+#ifndef CONFIG_LINUX
+    QemuMutex mutex;
+#endif
+    unsigned count;
+};
+
+/**
+ * qemu_lockcnt_init: initialize a QemuLockcnt
+ * @lockcnt: the lockcnt to initialize
+ *
+ * Initialize lockcnt's counter to zero and prepare its mutex
+ * for usage.
+ */
+void qemu_lockcnt_init(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_destroy: destroy a QemuLockcnt
+ * @lockcnt: the lockcnt to destruct
+ *
+ * Destroy lockcnt's mutex.
+ */
+void qemu_lockcnt_destroy(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_inc: increment a QemuLockCnt's counter
+ * @lockcnt: the lockcnt to operate on
+ *
+ * If the lockcnt's count is zero, wait for critical sections
+ * to finish and increment lockcnt's count to 1.  If the count
+ * is not zero, just increment it.
+ *
+ * Because this function can wait on the mutex, it must not be
+ * called while the lockcnt's mutex is held by the current thread.
+ * For the same reason, qemu_lockcnt_inc can also contribute to
+ * AB-BA deadlocks.  This is a sample deadlock scenario:
+ *
+ *            thread 1                      thread 2
+ *            -------------------------------------------------------
+ *            qemu_lockcnt_lock(&lc1);
+ *                                          qemu_lockcnt_lock(&lc2);
+ *            qemu_lockcnt_inc(&lc2);
+ *                                          qemu_lockcnt_inc(&lc1);
+ */
+void qemu_lockcnt_inc(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_dec: decrement a QemuLockCnt's counter
+ * @lockcnt: the lockcnt to operate on
+ */
+void qemu_lockcnt_dec(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_dec_and_lock: decrement a QemuLockCnt's counter and
+ * possibly lock it.
+ * @lockcnt: the lockcnt to operate on
+ *
+ * Decrement lockcnt's count.  If the new count is zero, lock
+ * the mutex and return true.  Otherwise, return false.
+ */
+bool qemu_lockcnt_dec_and_lock(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_dec_if_lock: possibly decrement a QemuLockCnt's counter and
+ * lock it.
+ * @lockcnt: the lockcnt to operate on
+ *
+ * If the count is 1, decrement the count to zero, lock
+ * the mutex and return true.  Otherwise, return false.
+ */
+bool qemu_lockcnt_dec_if_lock(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_lock: lock a QemuLockCnt's mutex.
+ * @lockcnt: the lockcnt to operate on
+ *
+ * Remember that concurrent visits are not blocked unless the count is
+ * also zero.  You can use qemu_lockcnt_count to check for this inside a
+ * critical section.
+ */
+void qemu_lockcnt_lock(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_unlock: release a QemuLockCnt's mutex.
+ * @lockcnt: the lockcnt to operate on.
+ */
+void qemu_lockcnt_unlock(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_inc_and_unlock: combined unlock/increment on a QemuLockCnt.
+ * @lockcnt: the lockcnt to operate on.
+ *
+ * This is the same as
+ *
+ *     qemu_lockcnt_unlock(lockcnt);
+ *     qemu_lockcnt_inc(lockcnt);
+ *
+ * but more efficient.
+ */
+void qemu_lockcnt_inc_and_unlock(QemuLockCnt *lockcnt);
+
+/**
+ * qemu_lockcnt_count: query a LockCnt's count.
+ * @lockcnt: the lockcnt to query.
+ *
+ * Note that the count can change at any time.  Still, while the
+ * lockcnt is locked, one can usefully check whether the count
+ * is non-zero.
+ */
+unsigned qemu_lockcnt_count(QemuLockCnt *lockcnt);
+
+#endif
diff --git a/include/qemu/thread.h b/include/qemu/thread.h
index fb74e21c08..7eba27a704 100644
--- a/include/qemu/thread.h
+++ b/include/qemu/thread.h
@@ -293,115 +293,4 @@ static inline void qemu_spin_unlock(QemuSpin *spin)
 #endif
 }
 
-struct QemuLockCnt {
-#ifndef CONFIG_LINUX
-    QemuMutex mutex;
-#endif
-    unsigned count;
-};
-
-/**
- * qemu_lockcnt_init: initialize a QemuLockcnt
- * @lockcnt: the lockcnt to initialize
- *
- * Initialize lockcnt's counter to zero and prepare its mutex
- * for usage.
- */
-void qemu_lockcnt_init(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_destroy: destroy a QemuLockcnt
- * @lockcnt: the lockcnt to destruct
- *
- * Destroy lockcnt's mutex.
- */
-void qemu_lockcnt_destroy(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_inc: increment a QemuLockCnt's counter
- * @lockcnt: the lockcnt to operate on
- *
- * If the lockcnt's count is zero, wait for critical sections
- * to finish and increment lockcnt's count to 1.  If the count
- * is not zero, just increment it.
- *
- * Because this function can wait on the mutex, it must not be
- * called while the lockcnt's mutex is held by the current thread.
- * For the same reason, qemu_lockcnt_inc can also contribute to
- * AB-BA deadlocks.  This is a sample deadlock scenario:
- *
- *            thread 1                      thread 2
- *            -------------------------------------------------------
- *            qemu_lockcnt_lock(&lc1);
- *                                          qemu_lockcnt_lock(&lc2);
- *            qemu_lockcnt_inc(&lc2);
- *                                          qemu_lockcnt_inc(&lc1);
- */
-void qemu_lockcnt_inc(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_dec: decrement a QemuLockCnt's counter
- * @lockcnt: the lockcnt to operate on
- */
-void qemu_lockcnt_dec(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_dec_and_lock: decrement a QemuLockCnt's counter and
- * possibly lock it.
- * @lockcnt: the lockcnt to operate on
- *
- * Decrement lockcnt's count.  If the new count is zero, lock
- * the mutex and return true.  Otherwise, return false.
- */
-bool qemu_lockcnt_dec_and_lock(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_dec_if_lock: possibly decrement a QemuLockCnt's counter and
- * lock it.
- * @lockcnt: the lockcnt to operate on
- *
- * If the count is 1, decrement the count to zero, lock
- * the mutex and return true.  Otherwise, return false.
- */
-bool qemu_lockcnt_dec_if_lock(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_lock: lock a QemuLockCnt's mutex.
- * @lockcnt: the lockcnt to operate on
- *
- * Remember that concurrent visits are not blocked unless the count is
- * also zero.  You can use qemu_lockcnt_count to check for this inside a
- * critical section.
- */
-void qemu_lockcnt_lock(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_unlock: release a QemuLockCnt's mutex.
- * @lockcnt: the lockcnt to operate on.
- */
-void qemu_lockcnt_unlock(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_inc_and_unlock: combined unlock/increment on a QemuLockCnt.
- * @lockcnt: the lockcnt to operate on.
- *
- * This is the same as
- *
- *     qemu_lockcnt_unlock(lockcnt);
- *     qemu_lockcnt_inc(lockcnt);
- *
- * but more efficient.
- */
-void qemu_lockcnt_inc_and_unlock(QemuLockCnt *lockcnt);
-
-/**
- * qemu_lockcnt_count: query a LockCnt's count.
- * @lockcnt: the lockcnt to query.
- *
- * Note that the count can change at any time.  Still, while the
- * lockcnt is locked, one can usefully check whether the count
- * is non-zero.
- */
-unsigned qemu_lockcnt_count(QemuLockCnt *lockcnt);
-
 #endif
diff --git a/util/aio-posix.c b/util/aio-posix.c
index 266c9dd35f..06bf9f456c 100644
--- a/util/aio-posix.c
+++ b/util/aio-posix.c
@@ -17,6 +17,7 @@
 #include "block/block.h"
 #include "block/thread-pool.h"
 #include "qemu/main-loop.h"
+#include "qemu/lockcnt.h"
 #include "qemu/rcu.h"
 #include "qemu/rcu_queue.h"
 #include "qemu/sockets.h"
diff --git a/util/aio-win32.c b/util/aio-win32.c
index d144f9391f..6583d5c5f3 100644
--- a/util/aio-win32.c
+++ b/util/aio-win32.c
@@ -18,6 +18,7 @@
 #include "qemu/osdep.h"
 #include "block/block.h"
 #include "qemu/main-loop.h"
+#include "qemu/lockcnt.h"
 #include "qemu/queue.h"
 #include "qemu/sockets.h"
 #include "qapi/error.h"
diff --git a/util/async.c b/util/async.c
index 3e3e4fc712..99db28389f 100644
--- a/util/async.c
+++ b/util/async.c
@@ -30,6 +30,7 @@
 #include "block/graph-lock.h"
 #include "qemu/main-loop.h"
 #include "qemu/atomic.h"
+#include "qemu/lockcnt.h"
 #include "qemu/rcu_queue.h"
 #include "block/raw-aio.h"
 #include "qemu/coroutine_int.h"
diff --git a/util/fdmon-epoll.c b/util/fdmon-epoll.c
index c6413cb18f..9fb8800dde 100644
--- a/util/fdmon-epoll.c
+++ b/util/fdmon-epoll.c
@@ -5,6 +5,7 @@
 
 #include "qemu/osdep.h"
 #include <sys/epoll.h>
+#include "qemu/lockcnt.h"
 #include "qemu/rcu_queue.h"
 #include "aio-posix.h"
 
diff --git a/util/lockcnt.c b/util/lockcnt.c
index 5da36946b1..d07c6cc5ce 100644
--- a/util/lockcnt.c
+++ b/util/lockcnt.c
@@ -7,6 +7,7 @@
  *   Paolo Bonzini <pbonzini@redhat.com>
  */
 #include "qemu/osdep.h"
+#include "qemu/lockcnt.h"
 #include "qemu/thread.h"
 #include "qemu/atomic.h"
 #include "trace.h"