diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
index 73e3a0edf5..eacd99e497 100644
--- a/util/qemu-thread-posix.c
+++ b/util/qemu-thread-posix.c
@@ -14,6 +14,7 @@
 #include "qemu/thread.h"
 #include "qemu/atomic.h"
 #include "qemu/notify.h"
+#include "trace.h"
 
 static bool name_threads;
 
@@ -60,17 +61,30 @@ void qemu_mutex_lock(QemuMutex *mutex)
     err = pthread_mutex_lock(&mutex->lock);
     if (err)
         error_exit(err, __func__);
+
+    trace_qemu_mutex_locked(mutex);
 }
 
 int qemu_mutex_trylock(QemuMutex *mutex)
 {
-    return pthread_mutex_trylock(&mutex->lock);
+    int err;
+
+    err = pthread_mutex_trylock(&mutex->lock);
+    if (err == 0) {
+        trace_qemu_mutex_locked(mutex);
+        return 0;
+    }
+    if (err != EBUSY) {
+        error_exit(err, __func__);
+    }
+    return -EBUSY;
 }
 
 void qemu_mutex_unlock(QemuMutex *mutex)
 {
     int err;
 
+    trace_qemu_mutex_unlocked(mutex);
     err = pthread_mutex_unlock(&mutex->lock);
     if (err)
         error_exit(err, __func__);
@@ -130,7 +144,9 @@ void qemu_cond_wait(QemuCond *cond, QemuMutex *mutex)
 {
     int err;
 
+    trace_qemu_mutex_unlocked(mutex);
     err = pthread_cond_wait(&cond->cond, &mutex->lock);
+    trace_qemu_mutex_locked(mutex);
     if (err)
         error_exit(err, __func__);
 }
diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c
index 59befd5202..653f29f442 100644
--- a/util/qemu-thread-win32.c
+++ b/util/qemu-thread-win32.c
@@ -19,6 +19,7 @@
 #include "qemu-common.h"
 #include "qemu/thread.h"
 #include "qemu/notify.h"
+#include "trace.h"
 #include <process.h>
 
 static bool name_threads;
@@ -55,6 +56,7 @@ void qemu_mutex_destroy(QemuMutex *mutex)
 void qemu_mutex_lock(QemuMutex *mutex)
 {
     AcquireSRWLockExclusive(&mutex->lock);
+    trace_qemu_mutex_locked(mutex);
 }
 
 int qemu_mutex_trylock(QemuMutex *mutex)
@@ -62,11 +64,16 @@ int qemu_mutex_trylock(QemuMutex *mutex)
     int owned;
 
     owned = TryAcquireSRWLockExclusive(&mutex->lock);
-    return !owned;
+    if (owned) {
+        trace_qemu_mutex_locked(mutex);
+        return 0;
+    }
+    return -EBUSY;
 }
 
 void qemu_mutex_unlock(QemuMutex *mutex)
 {
+    trace_qemu_mutex_unlocked(mutex);
     ReleaseSRWLockExclusive(&mutex->lock);
 }
 
@@ -118,7 +125,9 @@ void qemu_cond_broadcast(QemuCond *cond)
 
 void qemu_cond_wait(QemuCond *cond, QemuMutex *mutex)
 {
+    trace_qemu_mutex_unlocked(mutex);
     SleepConditionVariableSRW(&cond->var, &mutex->lock, INFINITE, 0);
+    trace_qemu_mutex_locked(mutex);
 }
 
 void qemu_sem_init(QemuSemaphore *sem, int init)
diff --git a/util/trace-events b/util/trace-events
index b44ef4f895..fa540c620b 100644
--- a/util/trace-events
+++ b/util/trace-events
@@ -55,3 +55,7 @@ lockcnt_futex_wait_prepare(const void *lockcnt, int expected, int new) "lockcnt
 lockcnt_futex_wait(const void *lockcnt, int val) "lockcnt %p waiting on %d"
 lockcnt_futex_wait_resume(const void *lockcnt, int new) "lockcnt %p after wait: %d"
 lockcnt_futex_wake(const void *lockcnt) "lockcnt %p waking up one waiter"
+
+# util/qemu-thread-posix.c
+qemu_mutex_locked(void *lock) "locked mutex %p"
+qemu_mutex_unlocked(void *lock) "unlocked mutex %p"