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

Andrew Morton
2019-12-05T00:50:50Z

From: Xiaoming Ni <nixiaoming@huawei.com>
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/1568861888-34045-4-git-send-email-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

include/linux/notifier.h | 4 ----
kernel/notifier.c | 23 -----------------------
net/sunrpc/rpc_pipe.c | 2 +-
3 files changed, 1 insertion(+), 28 deletions(-)

--- 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);

_