[PATCH] rcu: add rcu_bh_sync torture type to rcutorture

Use the newly-generic synchronous deferred free function to implement torture
testing for rcu_bh using synchronize_rcu_bh rather than the asynchronous
call_rcu_bh.

Signed-off-by: Josh Triplett <josh@freedesktop.org>
Acked-by: Paul E. McKenney <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 18 insertions, 3 deletions

diff --git a/Documentation/RCU/torture.txt b/Documentation/RCU/torture.txt
index 6714b5361158..cc4b1efe5ea8 100644
--- a/Documentation/RCU/torture.txt
+++ b/Documentation/RCU/torture.txt
@@ -55,8 +55,9 @@ test_no_idle_hz	Whether or not to test the ability of RCU to operate in
 
 torture_type    The type of RCU to test: "rcu" for the rcu_read_lock() API,
                 "rcu_sync" for rcu_read_lock() with synchronous reclamation,
-                "rcu_bh" for the rcu_read_lock_bh() API, and "srcu" for the
-                "srcu_read_lock()" API.
+                "rcu_bh" for the rcu_read_lock_bh() API, "rcu_bh_sync" for
+                rcu_read_lock_bh() with synchronous reclamation, and "srcu"
+                for the "srcu_read_lock()" API.
 
 verbose         Enable debug printk()s.  Default is disabled.
 
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 1c329df60bcc..0f0ff1556b5d 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -370,6 +370,19 @@ static struct rcu_torture_ops rcu_bh_ops = {
         .name = "rcu_bh"
 };
 
+static struct rcu_torture_ops rcu_bh_sync_ops = {
+        .init = rcu_sync_torture_init,
+        .cleanup = NULL,
+        .readlock = rcu_bh_torture_read_lock,
+        .readdelay = rcu_read_delay,  /* just reuse rcu's version. */
+        .readunlock = rcu_bh_torture_read_unlock,
+        .completed = rcu_bh_torture_completed,
+        .deferredfree = rcu_sync_torture_deferred_free,
+        .sync = rcu_bh_torture_synchronize,
+        .stats = NULL,
+        .name = "rcu_bh_sync"
+};
+
 /*
  * Definitions for srcu torture testing.
  */
@@ -452,7 +465,8 @@ static struct rcu_torture_ops srcu_ops = {
 };
 
 static struct rcu_torture_ops *torture_ops[] =
-        { &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &srcu_ops, NULL };
+        { &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &rcu_bh_sync_ops, &srcu_ops,
+          NULL };
 
 /*
  * RCU torture writer kthread.  Repeatedly substitutes a new structure