diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c
index b2e8e49..43e521e 100644
--- a/drivers/oprofile/buffer_sync.c
+++ b/drivers/oprofile/buffer_sync.c
@@ -108,10 +108,10 @@
 		return 0;
 
 	/* FIXME: should we process all CPU buffers ? */
-	down(&buffer_sem);
+	mutex_lock(&buffer_mutex);
 	add_event_entry(ESCAPE_CODE);
 	add_event_entry(MODULE_LOADED_CODE);
-	up(&buffer_sem);
+	mutex_unlock(&buffer_mutex);
 #endif
 	return 0;
 }
@@ -501,7 +501,7 @@
 	sync_buffer_state state = sb_buffer_start;
 	unsigned long available;
 
-	down(&buffer_sem);
+	mutex_lock(&buffer_mutex);
  
 	add_cpu_switch(cpu);
 
@@ -550,5 +550,5 @@
 
 	mark_done(cpu);
 
-	up(&buffer_sem);
+	mutex_unlock(&buffer_mutex);
 }
diff --git a/drivers/oprofile/event_buffer.c b/drivers/oprofile/event_buffer.c
index b80318f..04d6417 100644
--- a/drivers/oprofile/event_buffer.c
+++ b/drivers/oprofile/event_buffer.c
@@ -24,7 +24,7 @@
 #include "event_buffer.h"
 #include "oprofile_stats.h"
 
-DECLARE_MUTEX(buffer_sem);
+DEFINE_MUTEX(buffer_mutex);
  
 static unsigned long buffer_opened;
 static DECLARE_WAIT_QUEUE_HEAD(buffer_wait);
@@ -32,7 +32,7 @@
 static unsigned long buffer_size;
 static unsigned long buffer_watershed;
 static size_t buffer_pos;
-/* atomic_t because wait_event checks it outside of buffer_sem */
+/* atomic_t because wait_event checks it outside of buffer_mutex */
 static atomic_t buffer_ready = ATOMIC_INIT(0);
 
 /* Add an entry to the event buffer. When we
@@ -60,10 +60,10 @@
  */
 void wake_up_buffer_waiter(void)
 {
-	down(&buffer_sem);
+	mutex_lock(&buffer_mutex);
 	atomic_set(&buffer_ready, 1);
 	wake_up(&buffer_wait);
-	up(&buffer_sem);
+	mutex_unlock(&buffer_mutex);
 }
 
  
@@ -162,7 +162,7 @@
 	if (!atomic_read(&buffer_ready))
 		return -EAGAIN;
 
-	down(&buffer_sem);
+	mutex_lock(&buffer_mutex);
 
 	atomic_set(&buffer_ready, 0);
 
@@ -177,7 +177,7 @@
 	buffer_pos = 0;
  
 out:
-	up(&buffer_sem);
+	mutex_unlock(&buffer_mutex);
 	return retval;
 }
  
diff --git a/drivers/oprofile/event_buffer.h b/drivers/oprofile/event_buffer.h
index 0180236..9241627 100644
--- a/drivers/oprofile/event_buffer.h
+++ b/drivers/oprofile/event_buffer.h
@@ -11,7 +11,7 @@
 #define EVENT_BUFFER_H
 
 #include <linux/types.h> 
-#include <asm/semaphore.h>
+#include <asm/mutex.h>
  
 int alloc_event_buffer(void);
 
@@ -46,6 +46,6 @@
 /* mutex between sync_cpu_buffers() and the
  * file reading code.
  */
-extern struct semaphore buffer_sem;
+extern struct mutex buffer_mutex;
  
 #endif /* EVENT_BUFFER_H */
diff --git a/drivers/oprofile/oprof.c b/drivers/oprofile/oprof.c
index b3f1cd6..e5162a6 100644
--- a/drivers/oprofile/oprof.c
+++ b/drivers/oprofile/oprof.c
@@ -12,7 +12,7 @@
 #include <linux/init.h>
 #include <linux/oprofile.h>
 #include <linux/moduleparam.h>
-#include <asm/semaphore.h>
+#include <asm/mutex.h>
 
 #include "oprof.h"
 #include "event_buffer.h"
@@ -25,7 +25,7 @@
 unsigned long oprofile_started;
 unsigned long backtrace_depth;
 static unsigned long is_setup;
-static DECLARE_MUTEX(start_sem);
+static DEFINE_MUTEX(start_mutex);
 
 /* timer
    0 - use performance monitoring hardware if available
@@ -37,7 +37,7 @@
 {
 	int err;
  
-	down(&start_sem);
+	mutex_lock(&start_mutex);
 
 	if ((err = alloc_cpu_buffers()))
 		goto out;
@@ -57,7 +57,7 @@
 		goto out3;
 
 	is_setup = 1;
-	up(&start_sem);
+	mutex_unlock(&start_mutex);
 	return 0;
  
 out3:
@@ -68,7 +68,7 @@
 out1:
 	free_cpu_buffers();
 out:
-	up(&start_sem);
+	mutex_unlock(&start_mutex);
 	return err;
 }
 
@@ -78,7 +78,7 @@
 {
 	int err = -EINVAL;
  
-	down(&start_sem);
+	mutex_lock(&start_mutex);
  
 	if (!is_setup)
 		goto out;
@@ -95,7 +95,7 @@
 
 	oprofile_started = 1;
 out:
-	up(&start_sem); 
+	mutex_unlock(&start_mutex);
 	return err;
 }
 
@@ -103,7 +103,7 @@
 /* echo 0>/dev/oprofile/enable */
 void oprofile_stop(void)
 {
-	down(&start_sem);
+	mutex_lock(&start_mutex);
 	if (!oprofile_started)
 		goto out;
 	oprofile_ops.stop();
@@ -111,20 +111,20 @@
 	/* wake up the daemon to read what remains */
 	wake_up_buffer_waiter();
 out:
-	up(&start_sem);
+	mutex_unlock(&start_mutex);
 }
 
 
 void oprofile_shutdown(void)
 {
-	down(&start_sem);
+	mutex_lock(&start_mutex);
 	sync_stop();
 	if (oprofile_ops.shutdown)
 		oprofile_ops.shutdown();
 	is_setup = 0;
 	free_event_buffer();
 	free_cpu_buffers();
-	up(&start_sem);
+	mutex_unlock(&start_mutex);
 }
 
 
@@ -132,7 +132,7 @@
 {
 	int err = 0;
 
-	down(&start_sem);
+	mutex_lock(&start_mutex);
 
 	if (oprofile_started) {
 		err = -EBUSY;
@@ -147,7 +147,7 @@
 	backtrace_depth = val;
 
 out:
-	up(&start_sem);
+	mutex_unlock(&start_mutex);
 	return err;
 }