netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v3 1/9] net: core: use this_cpu_ptr per-cpu helper
@ 2012-11-09  2:20 Shan Wei
  2012-11-09 20:08 ` Christoph Lameter
  0 siblings, 1 reply; 4+ messages in thread
From: Shan Wei @ 2012-11-09  2:20 UTC (permalink / raw)
  To: David Miller, timo.teras, steffen.klassert, NetDev,
	Kernel-Maillist, cl, Shan Wei

From: Shan Wei <davidshan@tencent.com>

flush_tasklet is a struct, not a pointer in percpu var.
so use this_cpu_ptr to get the member pointer.

Signed-off-by: Shan Wei <davidshan@tencent.com>
---
 net/core/flow.c |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/net/core/flow.c b/net/core/flow.c
index e318c7e..b0901ee 100644
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -327,11 +327,9 @@ static void flow_cache_flush_tasklet(unsigned long data)
 static void flow_cache_flush_per_cpu(void *data)
 {
 	struct flow_flush_info *info = data;
-	int cpu;
 	struct tasklet_struct *tasklet;
 
-	cpu = smp_processor_id();
-	tasklet = &per_cpu_ptr(info->cache->percpu, cpu)->flush_tasklet;
+	tasklet = this_cpu_ptr(&info->cache->percpu->flush_tasklet);
 	tasklet->data = (unsigned long)info;
 	tasklet_schedule(tasklet);
 }
-- 
1.7.1

^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH v3 1/9] net: core: use this_cpu_ptr per-cpu helper
  2012-11-09  2:20 [PATCH v3 1/9] net: core: use this_cpu_ptr per-cpu helper Shan Wei
@ 2012-11-09 20:08 ` Christoph Lameter
  2012-11-09 20:15   ` Eric Dumazet
  0 siblings, 1 reply; 4+ messages in thread
From: Christoph Lameter @ 2012-11-09 20:08 UTC (permalink / raw)
  To: Shan Wei
  Cc: David Miller, timo.teras, steffen.klassert, NetDev,
	Kernel-Maillist

On Fri, 9 Nov 2012, Shan Wei wrote:

> diff --git a/net/core/flow.c b/net/core/flow.c
> index e318c7e..b0901ee 100644
> --- a/net/core/flow.c
> +++ b/net/core/flow.c
> @@ -327,11 +327,9 @@ static void flow_cache_flush_tasklet(unsigned long data)
>  static void flow_cache_flush_per_cpu(void *data)
>  {
>  	struct flow_flush_info *info = data;
> -	int cpu;
>  	struct tasklet_struct *tasklet;
>
> -	cpu = smp_processor_id();
> -	tasklet = &per_cpu_ptr(info->cache->percpu, cpu)->flush_tasklet;
> +	tasklet = this_cpu_ptr(&info->cache->percpu->flush_tasklet);
>  	tasklet->data = (unsigned long)info;

this_cpu_write(info->cache->percpu->flush_tasklet->data, (unsigned
	long)info);

should also do the trick in less instructions and get rid of all temporary
variables as well.

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v3 1/9] net: core: use this_cpu_ptr per-cpu helper
  2012-11-09 20:08 ` Christoph Lameter
@ 2012-11-09 20:15   ` Eric Dumazet
  2012-11-12 23:29     ` Christoph Lameter
  0 siblings, 1 reply; 4+ messages in thread
From: Eric Dumazet @ 2012-11-09 20:15 UTC (permalink / raw)
  To: Christoph Lameter
  Cc: Shan Wei, David Miller, timo.teras, steffen.klassert, NetDev,
	Kernel-Maillist

On Fri, 2012-11-09 at 20:08 +0000, Christoph Lameter wrote:
> On Fri, 9 Nov 2012, Shan Wei wrote:
> 
> > diff --git a/net/core/flow.c b/net/core/flow.c
> > index e318c7e..b0901ee 100644
> > --- a/net/core/flow.c
> > +++ b/net/core/flow.c
> > @@ -327,11 +327,9 @@ static void flow_cache_flush_tasklet(unsigned long data)
> >  static void flow_cache_flush_per_cpu(void *data)
> >  {
> >  	struct flow_flush_info *info = data;
> > -	int cpu;
> >  	struct tasklet_struct *tasklet;
> >
> > -	cpu = smp_processor_id();
> > -	tasklet = &per_cpu_ptr(info->cache->percpu, cpu)->flush_tasklet;
> > +	tasklet = this_cpu_ptr(&info->cache->percpu->flush_tasklet);
> >  	tasklet->data = (unsigned long)info;
> 
> this_cpu_write(info->cache->percpu->flush_tasklet->data, (unsigned
> 	long)info);
> 
> should also do the trick in less instructions and get rid of all temporary
> variables as well.

Its not the case.

We need the _pointer_ to call :

tasklet_schedule(tasklet);

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v3 1/9] net: core: use this_cpu_ptr per-cpu helper
  2012-11-09 20:15   ` Eric Dumazet
@ 2012-11-12 23:29     ` Christoph Lameter
  0 siblings, 0 replies; 4+ messages in thread
From: Christoph Lameter @ 2012-11-12 23:29 UTC (permalink / raw)
  To: Eric Dumazet
  Cc: Shan Wei, David Miller, timo.teras, steffen.klassert, NetDev,
	Kernel-Maillist

On Fri, 9 Nov 2012, Eric Dumazet wrote:

> Its not the case.
>
> We need the _pointer_ to call :
>
> tasklet_schedule(tasklet);

Ah. Ok. In that case

Reviewed-by: Christoph Lameter <cl@linux.com>

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2012-11-12 23:29 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2012-11-09  2:20 [PATCH v3 1/9] net: core: use this_cpu_ptr per-cpu helper Shan Wei
2012-11-09 20:08 ` Christoph Lameter
2012-11-09 20:15   ` Eric Dumazet
2012-11-12 23:29     ` Christoph Lameter

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).