[21/86] kernel/notifier.c: remove blocking_notifier_chain_cond_register()

Commit Message

Andrew Morton Dec. 5, 2019, 12:50 a.m. UTC

From: Xiaoming Ni <[e-mail]>
Subject: kernel/notifier.c: remove blocking_notifier_chain_cond_register()

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()

Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Xiaoming Ni <[e-mail]>
Reviewed-by: Andrew Morton <[e-mail]>
Cc: Alan Stern <[e-mail]>
Cc: Alexey Dobriyan <[e-mail]>
Cc: Andy Lutomirski <[e-mail]>
Cc: Anna Schumaker <[e-mail]>
Cc: Arjan van de Ven <[e-mail]>
Cc: Chuck Lever <[e-mail]>
Cc: David S. Miller <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: J. Bruce Fields <[e-mail]>
Cc: Jeff Layton <[e-mail]>
Cc: Nadia Derbey <[e-mail]>
Cc: "Paul E. McKenney" <[e-mail]>
Cc: Sam Protsenko <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Trond Myklebust <[e-mail]>
Cc: Vasily Averin <[e-mail]>
Cc: Viresh Kumar <[e-mail]>
Cc: YueHaibing <[e-mail]>
Signed-off-by: Andrew Morton <[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

--- a/include/linux/notifier.h~kernel-notifierc-remove-blocking_notifier_chain_cond_register
+++ a/include/linux/notifier.h
@@ -150,10 +150,6 @@  extern int raw_notifier_chain_register(s
 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,
--- a/kernel/notifier.c~kernel-notifierc-remove-blocking_notifier_chain_cond_register
+++ a/kernel/notifier.c
@@ -221,29 +221,6 @@  int blocking_notifier_chain_register(str
 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
--- a/net/sunrpc/rpc_pipe.c~kernel-notifierc-remove-blocking_notifier_chain_cond_register
+++ a/net/sunrpc/rpc_pipe.c
@@ -51,7 +51,7 @@  static BLOCKING_NOTIFIER_HEAD(rpc_pipefs
 
 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);