markers: fix unregister bug and reenter bug, cleanup

Use the new rcu_read_lock_sched/unlock_sched() in marker code around the call
site instead of preempt_disable/enable(). It helps reviewing the code more
easily.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 8 insertions, 8 deletions

diff --git a/kernel/marker.c b/kernel/marker.c
index 9f76c4a622ec..fe5ca72f9659 100644
--- a/kernel/marker.c
+++ b/kernel/marker.c
@@ -100,11 +100,11 @@ void marker_probe_cb(const struct marker *mdata, void *call_private, ...)
         char ptype;
 
         /*
-         * preempt_disable does two things : disabling preemption to make sure
-         * the teardown of the callbacks can be done correctly when they are in
-         * modules and they insure RCU read coherency.
+         * rcu_read_lock_sched does two things : disabling preemption to make
+         * sure the teardown of the callbacks can be done correctly when they
+         * are in modules and they insure RCU read coherency.
          */
-        preempt_disable();
+        rcu_read_lock_sched();
         ptype = mdata->ptype;
         if (likely(!ptype)) {
                 marker_probe_func *func;
@@ -142,7 +142,7 @@ void marker_probe_cb(const struct marker *mdata, void *call_private, ...)
                         va_end(args);
                 }
         }
-        preempt_enable();
+        rcu_read_unlock_sched();
 }
 EXPORT_SYMBOL_GPL(marker_probe_cb);
 
@@ -159,7 +159,7 @@ void marker_probe_cb_noarg(const struct marker *mdata, void *call_private, ...)
         va_list args;   /* not initialized */
         char ptype;
 
-        preempt_disable();
+        rcu_read_lock_sched();
         ptype = mdata->ptype;
         if (likely(!ptype)) {
                 marker_probe_func *func;
@@ -192,7 +192,7 @@ void marker_probe_cb_noarg(const struct marker *mdata, void *call_private, ...)
                         multi[i].func(multi[i].probe_private, call_private,
                                 mdata->format, &args);
         }
-        preempt_enable();
+        rcu_read_unlock_sched();
 }
 EXPORT_SYMBOL_GPL(marker_probe_cb_noarg);
 
@@ -539,7 +539,7 @@ static int set_marker(struct marker_entry **entry, struct marker *elem,
  * Disable a marker and its probe callback.
  * Note: only waiting an RCU period after setting elem->call to the empty
  * function insures that the original callback is not used anymore. This insured
- * by preempt_disable around the call site.
+ * by rcu_read_lock_sched around the call site.
  */
 static void disable_marker(struct marker *elem)
 {