[PATCH 1/2] locking/rwsem: EXPORT_SYMBOL follows function definition

[PATCH 1/2] locking/rwsem: EXPORT_SYMBOL follows function definition

[Davidlohr Bueso]

rw-semaphore is the only type of lock doing this ugliness of
exporting at the end of the file.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 kernel/locking/rwsem-xadd.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c
index d6203fa..12166ec 100644
--- a/kernel/locking/rwsem-xadd.c
+++ b/kernel/locking/rwsem-xadd.c
@@ -246,6 +246,7 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
 
 	return sem;
 }
+EXPORT_SYMBOL(rwsem_down_read_failed);
 
 static inline bool rwsem_try_write_lock(long count, struct rw_semaphore *sem)
 {
@@ -465,6 +466,7 @@ struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem)
 
 	return sem;
 }
+EXPORT_SYMBOL(rwsem_down_write_failed);
 
 /*
  * handle waking up a waiter on the semaphore
@@ -485,6 +487,7 @@ struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem)
 
 	return sem;
 }
+EXPORT_SYMBOL(rwsem_wake);
 
 /*
  * downgrade a write lock into a read lock
@@ -506,8 +509,4 @@ struct rw_semaphore *rwsem_downgrade_wake(struct rw_semaphore *sem)
 
 	return sem;
 }
-
-EXPORT_SYMBOL(rwsem_down_read_failed);
-EXPORT_SYMBOL(rwsem_down_write_failed);
-EXPORT_SYMBOL(rwsem_wake);
 EXPORT_SYMBOL(rwsem_downgrade_wake);
-- 
1.8.4.5

[PATCH 2/2] locking/rwsem-spinlock: Cleanup down_read()

[Davidlohr Bueso]

... when returning from a successful lock acquisition. The horror!

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 kernel/locking/rwsem-spinlock.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/kernel/locking/rwsem-spinlock.c b/kernel/locking/rwsem-spinlock.c
index 2c93571..07e456c 100644
--- a/kernel/locking/rwsem-spinlock.c
+++ b/kernel/locking/rwsem-spinlock.c
@@ -130,7 +130,7 @@ void __sched __down_read(struct rw_semaphore *sem)
 		/* granted */
 		sem->count++;
 		raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
-		goto out;
+		return;
 	}
 
 	tsk = current;
@@ -155,8 +155,6 @@ void __sched __down_read(struct rw_semaphore *sem)
 	}
 
 	tsk->state = TASK_RUNNING;
- out:
-	;
 }
 
 /*
-- 
1.8.4.5

Re: [PATCH 2/2] locking/rwsem-spinlock: Cleanup down_read()

[Ingo Molnar]

* Davidlohr Bueso <dave@stgolabs.net> wrote:

> ... when returning from a successful lock acquisition. The horror!
> 
> Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
> ---
>  kernel/locking/rwsem-spinlock.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/kernel/locking/rwsem-spinlock.c b/kernel/locking/rwsem-spinlock.c
> index 2c93571..07e456c 100644
> --- a/kernel/locking/rwsem-spinlock.c
> +++ b/kernel/locking/rwsem-spinlock.c
> @@ -130,7 +130,7 @@ void __sched __down_read(struct rw_semaphore *sem)
>  		/* granted */
>  		sem->count++;
>  		raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
> -		goto out;
> +		return;
>  	}
>  
>  	tsk = current;
> @@ -155,8 +155,6 @@ void __sched __down_read(struct rw_semaphore *sem)
>  	}
>  
>  	tsk->state = TASK_RUNNING;
> - out:
> -	;
>  }

It following an existing 'out' pattern found elsewhere in the 
file - I don't think there's much wrong about that per se - 
especially in locking code we try to not return from the middle 
of the flow.

Thanks,

	Ingo

[tip:locking/core] locking/rwsem: Move EXPORT_SYMBOL() lines to follow function definition

[tip-bot for Davidlohr Bueso]

Commit-ID:  db0e716a1512179e8374a74c1f3184e9ce15d138
Gitweb:     http://git.kernel.org/tip/db0e716a1512179e8374a74c1f3184e9ce15d138
Author:     Davidlohr Bueso <dave@stgolabs.net>
AuthorDate: Thu, 11 Sep 2014 22:34:25 -0700
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 16 Sep 2014 09:49:01 +0200

locking/rwsem: Move EXPORT_SYMBOL() lines to follow function definition

rw-semaphore is the only type of lock doing this ugliness of
exporting at the end of the file.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: dave@stgolabs.net
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1410500066-5909-1-git-send-email-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/locking/rwsem-xadd.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c
index d6203fa..12166ec 100644
--- a/kernel/locking/rwsem-xadd.c
+++ b/kernel/locking/rwsem-xadd.c
@@ -246,6 +246,7 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
 
 	return sem;
 }
+EXPORT_SYMBOL(rwsem_down_read_failed);
 
 static inline bool rwsem_try_write_lock(long count, struct rw_semaphore *sem)
 {
@@ -465,6 +466,7 @@ struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem)
 
 	return sem;
 }
+EXPORT_SYMBOL(rwsem_down_write_failed);
 
 /*
  * handle waking up a waiter on the semaphore
@@ -485,6 +487,7 @@ struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem)
 
 	return sem;
 }
+EXPORT_SYMBOL(rwsem_wake);
 
 /*
  * downgrade a write lock into a read lock
@@ -506,8 +509,4 @@ struct rw_semaphore *rwsem_downgrade_wake(struct rw_semaphore *sem)
 
 	return sem;
 }
-
-EXPORT_SYMBOL(rwsem_down_read_failed);
-EXPORT_SYMBOL(rwsem_down_write_failed);
-EXPORT_SYMBOL(rwsem_wake);
 EXPORT_SYMBOL(rwsem_downgrade_wake);