[v4,3/3] kernel/notifier.c: remove blocking_notifier_chain_cond_register()

Commit Message

Xiaoming Ni Sept. 19, 2019, 2:58 a.m. UTC

blocking_notifier_chain_cond_register() does not consider
system_booting state, which is the only difference between this
function and blocking_notifier_cain_register(). This can be a bug
and is a piece of duplicate code.

Delete blocking_notifier_chain_cond_register()

Signed-off-by: Xiaoming Ni <[e-mail]>
---
 include/linux/notifier.h |  4 ----
 kernel/notifier.c        | 23 -----------------------
 net/sunrpc/rpc_pipe.c    |  2 +-
 3 files changed, 1 insertion(+), 28 deletions(-)

Patch

diff --git a/include/linux/notifier.h b/include/linux/notifier.h
index 0096a05..0189476 100644
--- a/include/linux/notifier.h
+++ b/include/linux/notifier.h
@@ -150,10 +150,6 @@  extern int raw_notifier_chain_register(struct raw_notifier_head *nh,
 extern int srcu_notifier_chain_register(struct srcu_notifier_head *nh,
 		struct notifier_block *nb);
 
-extern int blocking_notifier_chain_cond_register(
-		struct blocking_notifier_head *nh,
-		struct notifier_block *nb);
-
 extern int atomic_notifier_chain_unregister(struct atomic_notifier_head *nh,
 		struct notifier_block *nb);
 extern int blocking_notifier_chain_unregister(struct blocking_notifier_head *nh,
diff --git a/kernel/notifier.c b/kernel/notifier.c
index e3d221f..63d7501 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -221,29 +221,6 @@  int blocking_notifier_chain_register(struct blocking_notifier_head *nh,
 EXPORT_SYMBOL_GPL(blocking_notifier_chain_register);
 
 /**
- *	blocking_notifier_chain_cond_register - Cond add notifier to a blocking notifier chain
- *	@nh: Pointer to head of the blocking notifier chain
- *	@n: New entry in notifier chain
- *
- *	Adds a notifier to a blocking notifier chain, only if not already
- *	present in the chain.
- *	Must be called in process context.
- *
- *	Currently always returns zero.
- */
-int blocking_notifier_chain_cond_register(struct blocking_notifier_head *nh,
-		struct notifier_block *n)
-{
-	int ret;
-
-	down_write(&nh->rwsem);
-	ret = notifier_chain_register(&nh->head, n);
-	up_write(&nh->rwsem);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(blocking_notifier_chain_cond_register);
-
-/**
  *	blocking_notifier_chain_unregister - Remove notifier from a blocking notifier chain
  *	@nh: Pointer to head of the blocking notifier chain
  *	@n: Entry to remove from notifier chain
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index b71a39d..39e14d5 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -51,7 +51,7 @@ 
 
 int rpc_pipefs_notifier_register(struct notifier_block *nb)
 {
-	return blocking_notifier_chain_cond_register(&rpc_pipefs_notifier_list, nb);
+	return blocking_notifier_chain_register(&rpc_pipefs_notifier_list, nb);
 }
 EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_register);