X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=doc%2Fexamples%2Furcu-flavors%2Fqsbr.c;h=6f5b9b51d46b796adcaf26792dcfcfd5eb1b1c4f;hp=1c50b8aedaf9b368309acc92e3b5bf840437f7a0;hb=238eb13d671cc39e181203923ccae3e5c5b84148;hpb=6df9f02d9de67572ab8bd34855eca233c16ced47

diff --git a/doc/examples/urcu-flavors/qsbr.c b/doc/examples/urcu-flavors/qsbr.c
index 1c50b8a..6f5b9b5 100644
--- a/doc/examples/urcu-flavors/qsbr.c
+++ b/doc/examples/urcu-flavors/qsbr.c
@@ -16,6 +16,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include <unistd.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdint.h>
@@ -84,21 +85,12 @@ int main(int argc, char **argv)
 			goto end;
 	}
 
-	/*
-	 * For all RCU flavors except QSBR, we need to explicitly mark
-	 * RCU read-side critical sections with rcu_read_lock() and
-	 * rcu_read_unlock(). They can be nested. Those are no-ops for
-	 * the QSBR flavor.
-	 */
-	rcu_read_lock();
-
 	/*
 	 * RCU traversal of the linked list.
 	 */
 	cds_list_for_each_entry_rcu(node, &mylist, node) {
 		printf("Value: %" PRIu64 "\n", node->value);
 	}
-	rcu_read_unlock();
 
 	/*
 	 * Removing nodes from linked list. Safe against concurrent RCU
@@ -106,6 +98,12 @@ int main(int argc, char **argv)
 	 */
 	cds_list_for_each_entry_safe(node, n, &mylist, node) {
 		cds_list_del_rcu(&node->node);
+		/*
+		 * call_rcu() will ensure that the handler
+		 * "rcu_free_node" is executed after a grace period.
+		 * call_rcu() can be called from RCU read-side critical
+		 * sections.
+		 */
 		call_rcu(&node->rcu_head, rcu_free_node);
 	}