Merge branch 'akpm-current/current'

[karo-tx-linux.git] / tools / testing / radix-tree / rcupdate.c

diff --git a/tools/testing/radix-tree/rcupdate.c b/tools/testing/radix-tree/rcupdate.c
new file mode 100644 (file)
index 0000000..31a2d14
--- /dev/null
+++ b/tools/testing/radix-tree/rcupdate.c
@@ -0,0 +1,86 @@
+#include <linux/rcupdate.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <assert.h>
+
+static pthread_mutex_t rculock = PTHREAD_MUTEX_INITIALIZER;
+static struct rcu_head *rcuhead_global = NULL;
+static __thread int nr_rcuhead = 0;
+static __thread struct rcu_head *rcuhead = NULL;
+static __thread struct rcu_head *rcutail = NULL;
+
+static pthread_cond_t rcu_worker_cond = PTHREAD_COND_INITIALIZER;
+
+/* switch to urcu implementation when it is merged. */
+void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *head))
+{
+       head->func = func;
+       head->next = rcuhead;
+       rcuhead = head;
+       if (!rcutail)
+               rcutail = head;
+       nr_rcuhead++;
+       if (nr_rcuhead >= 1000) {
+               int signal = 0;
+
+               pthread_mutex_lock(&rculock);
+               if (!rcuhead_global)
+                       signal = 1;
+               rcutail->next = rcuhead_global;
+               rcuhead_global = head;
+               pthread_mutex_unlock(&rculock);
+
+               nr_rcuhead = 0;
+               rcuhead = NULL;
+               rcutail = NULL;
+
+               if (signal) {
+                       pthread_cond_signal(&rcu_worker_cond);
+               }
+       }
+}
+
+static void *rcu_worker(void *arg)
+{
+       struct rcu_head *r;
+
+       rcupdate_thread_init();
+
+       while (1) {
+               pthread_mutex_lock(&rculock);
+               while (!rcuhead_global) {
+                       pthread_cond_wait(&rcu_worker_cond, &rculock);
+               }
+               r = rcuhead_global;
+               rcuhead_global = NULL;
+
+               pthread_mutex_unlock(&rculock);
+
+               synchronize_rcu();
+
+               while (r) {
+                       struct rcu_head *tmp = r->next;
+                       r->func(r);
+                       r = tmp;
+               }
+       }
+
+       rcupdate_thread_exit();
+
+       return NULL;
+}
+
+static pthread_t worker_thread;
+void rcupdate_init(void)
+{
+       pthread_create(&worker_thread, NULL, rcu_worker, NULL);
+}
+
+void rcupdate_thread_init(void)
+{
+       rcu_register_thread();
+}
+void rcupdate_thread_exit(void)
+{
+       rcu_unregister_thread();
+}