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* [PATCH] libfs: Replace rcu_assign_pointer() with RCU_INIT_POINTER()
@ 2014-08-18 14:56 Andreea-Cristina Bernat
  2014-09-25 22:01 ` Vasu Dev
  0 siblings, 1 reply; 3+ messages in thread
From: Andreea-Cristina Bernat @ 2014-08-18 14:56 UTC (permalink / raw)
  To: robert.w.love, JBottomley, fcoe-devel, linux-scsi, linux-kernel; +Cc: paulmck

The uses of "rcu_assign_pointer()" are NULLing out the pointers.
According to RCU_INIT_POINTER()'s block comment:
"1.   This use of RCU_INIT_POINTER() is NULLing out the pointer"
it is better to use it instead of rcu_assign_pointer() because it has a
smaller overhead.

The following Coccinelle semantic patch was used:
@@
@@

- rcu_assign_pointer
+ RCU_INIT_POINTER
  (..., NULL)

Signed-off-by: Andreea-Cristina Bernat <bernat.ada@gmail.com>
---
 drivers/scsi/libfc/fc_libfc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/libfc/fc_libfc.c b/drivers/scsi/libfc/fc_libfc.c
index 8d65a51a..c11a638 100644
--- a/drivers/scsi/libfc/fc_libfc.c
+++ b/drivers/scsi/libfc/fc_libfc.c
@@ -296,9 +296,9 @@ void fc_fc4_deregister_provider(enum fc_fh_type type, struct fc4_prov *prov)
 	BUG_ON(type >= FC_FC4_PROV_SIZE);
 	mutex_lock(&fc_prov_mutex);
 	if (prov->recv)
-		rcu_assign_pointer(fc_passive_prov[type], NULL);
+		RCU_INIT_POINTER(fc_passive_prov[type], NULL);
 	else
-		rcu_assign_pointer(fc_active_prov[type], NULL);
+		RCU_INIT_POINTER(fc_active_prov[type], NULL);
 	mutex_unlock(&fc_prov_mutex);
 	synchronize_rcu();
 }
-- 
1.9.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] libfs: Replace rcu_assign_pointer() with RCU_INIT_POINTER()
  2014-08-18 14:56 [PATCH] libfs: Replace rcu_assign_pointer() with RCU_INIT_POINTER() Andreea-Cristina Bernat
@ 2014-09-25 22:01 ` Vasu Dev
  2014-09-30 15:36   ` Christoph Hellwig
  0 siblings, 1 reply; 3+ messages in thread
From: Vasu Dev @ 2014-09-25 22:01 UTC (permalink / raw)
  To: Andreea-Cristina Bernat
  Cc: robert.w.love, JBottomley, fcoe-devel, linux-scsi, linux-kernel,
	paulmck

On Mon, 2014-08-18 at 17:56 +0300, Andreea-Cristina Bernat wrote:
> The uses of "rcu_assign_pointer()" are NULLing out the pointers.
> According to RCU_INIT_POINTER()'s block comment:
> "1.   This use of RCU_INIT_POINTER() is NULLing out the pointer"
> it is better to use it instead of rcu_assign_pointer() because it has a
> smaller overhead.
> 
> The following Coccinelle semantic patch was used:
> @@
> @@
> 
> - rcu_assign_pointer
> + RCU_INIT_POINTER
>   (..., NULL)
> 
> Signed-off-by: Andreea-Cristina Bernat <bernat.ada@gmail.com>
> ---
>  drivers/scsi/libfc/fc_libfc.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/libfc/fc_libfc.c b/drivers/scsi/libfc/fc_libfc.c
> index 8d65a51a..c11a638 100644
> --- a/drivers/scsi/libfc/fc_libfc.c
> +++ b/drivers/scsi/libfc/fc_libfc.c
> @@ -296,9 +296,9 @@ void fc_fc4_deregister_provider(enum fc_fh_type type, struct fc4_prov *prov)
>  	BUG_ON(type >= FC_FC4_PROV_SIZE);
>  	mutex_lock(&fc_prov_mutex);
>  	if (prov->recv)
> -		rcu_assign_pointer(fc_passive_prov[type], NULL);
> +		RCU_INIT_POINTER(fc_passive_prov[type], NULL);
>  	else
> -		rcu_assign_pointer(fc_active_prov[type], NULL);
> +		RCU_INIT_POINTER(fc_active_prov[type], NULL);
>  	mutex_unlock(&fc_prov_mutex);
>  	synchronize_rcu();
>  }

Looks like patch is not yet applied.

Acked-by: Vasu Dev <vasu.dev@intel.com>



^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] libfs: Replace rcu_assign_pointer() with RCU_INIT_POINTER()
  2014-09-25 22:01 ` Vasu Dev
@ 2014-09-30 15:36   ` Christoph Hellwig
  0 siblings, 0 replies; 3+ messages in thread
From: Christoph Hellwig @ 2014-09-30 15:36 UTC (permalink / raw)
  To: Vasu Dev
  Cc: Andreea-Cristina Bernat, robert.w.love, JBottomley, fcoe-devel,
	linux-scsi, linux-kernel, paulmck

Thanks,

applied to drivers-for-3.18

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2014-09-30 15:37 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2014-08-18 14:56 [PATCH] libfs: Replace rcu_assign_pointer() with RCU_INIT_POINTER() Andreea-Cristina Bernat
2014-09-25 22:01 ` Vasu Dev
2014-09-30 15:36   ` Christoph Hellwig

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