Patchwork [v3,3/9] net: xfrm: use __this_cpu_read per-cpu helper

login
register
mail settings
Submitter Shan Wei
Date Nov. 9, 2012, 2:20 a.m.
Message ID <509C688B.5010502@gmail.com>
Download mbox | patch
Permalink /patch/197917/
State Not Applicable
Delegated to: David Miller
Headers show

Comments

Shan Wei - Nov. 9, 2012, 2:20 a.m.
From: Shan Wei <davidshan@tencent.com>


Signed-off-by: Shan Wei <davidshan@tencent.com>
---
v3 fix compile warning:
net/xfrm/xfrm_ipcomp.c: In function 'ipcomp_alloc_tfms':
net/xfrm/xfrm_ipcomp.c:285: warning: assignment from incompatible pointer type

---
 net/xfrm/xfrm_ipcomp.c |    7 ++-----
 1 files changed, 2 insertions(+), 5 deletions(-)
Christoph Lameter - Nov. 9, 2012, 8:12 p.m.
On Fri, 9 Nov 2012, Shan Wei wrote:

> v3 fix compile warning:
> net/xfrm/xfrm_ipcomp.c: In function 'ipcomp_alloc_tfms':
> net/xfrm/xfrm_ipcomp.c:285: warning: assignment from incompatible pointer type

Why exactly is the pointer type not compatible? Looks like we have a
problem here.

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Shan Wei - Nov. 12, 2012, 1:45 a.m.
Christoph Lameter said, at 2012/11/10 4:12:
> On Fri, 9 Nov 2012, Shan Wei wrote:
> 
>> v3 fix compile warning:
>> net/xfrm/xfrm_ipcomp.c: In function 'ipcomp_alloc_tfms':
>> net/xfrm/xfrm_ipcomp.c:285: warning: assignment from incompatible pointer type
> 
> Why exactly is the pointer type not compatible? Looks like we have a
> problem here.
> 

pos->tfms(struct crypto_comp **tfms) is a double pointer that point to struct crypto_comp.
returned value is a pointer that point to struct crypto_comp;
So, we need to dereference and then read.

+ tfm = __this_cpu_read(*pos->tfms);

I will update this patch in v4 to fix it.

Thanks~
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Patch

diff --git a/net/xfrm/xfrm_ipcomp.c b/net/xfrm/xfrm_ipcomp.c
index e5246fb..898c899 100644
--- a/net/xfrm/xfrm_ipcomp.c
+++ b/net/xfrm/xfrm_ipcomp.c
@@ -276,18 +276,15 @@  static struct crypto_comp * __percpu *ipcomp_alloc_tfms(const char *alg_name)
 	struct crypto_comp * __percpu *tfms;
 	int cpu;
 
-	/* This can be any valid CPU ID so we don't need locking. */
-	cpu = raw_smp_processor_id();
 
 	list_for_each_entry(pos, &ipcomp_tfms_list, list) {
 		struct crypto_comp *tfm;
 
-		tfms = pos->tfms;
-		tfm = *per_cpu_ptr(tfms, cpu);
+		tfm = (struct crypto_comp *) __this_cpu_read(pos->tfms);
 
 		if (!strcmp(crypto_comp_name(tfm), alg_name)) {
 			pos->users++;
-			return tfms;
+			return pos->tfms;
 		}
 	}