diff mbox

[v3.5,10/19] mac8011: slight optimization of addr compare

Message ID 52BC15C8.2080400@huawei.com
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Ding Tianhong Dec. 26, 2013, 11:40 a.m. UTC 
Use the possibly more efficient ether_addr_equal
to instead of memcmp.

Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: David Miller <davem@davemloft.net>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
---
 net/mac80211/iface.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

Comments

Johannes Berg Jan. 6, 2014, 3:11 p.m. UTC | #1 
On Thu, 2013-12-26 at 19:40 +0800, Ding Tianhong wrote:
> Use the possibly more efficient ether_addr_equal
> to instead of memcmp.

This is a slow-path, I don't think that's really worth it. It kinda
makes sense, but relies on the struct mac_address allocation for
alignment and the fact that there are no other members in that struct,
so it seems to me that this ought to also add some alignment attributes?

johannes


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Ding Tianhong Jan. 7, 2014, 3:40 a.m. UTC | #2 
On 2014/1/6 23:11, Johannes Berg wrote:
> On Thu, 2013-12-26 at 19:40 +0800, Ding Tianhong wrote:
>> Use the possibly more efficient ether_addr_equal
>> to instead of memcmp.
> 
> This is a slow-path, I don't think that's really worth it. It kinda
> makes sense, but relies on the struct mac_address allocation for
> alignment and the fact that there are no other members in that struct,
> so it seems to me that this ought to also add some alignment attributes?
> 
> johannes
> 
> 

Yes, I had to say that it is really a slight optimization.And I am sure the address in the struct
is alignment, otherwise I have to use the ether_addr_equal_unaligned().

Regards
Ding 

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> 


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diff mbox

Patch

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 7aa9f9d..a4f9812 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1497,8 +1497,8 @@  static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
 			bool used = false;
 
 			list_for_each_entry(sdata, &local->interfaces, list) {
-				if (memcmp(local->hw.wiphy->addresses[i].addr,
-					   sdata->vif.addr, ETH_ALEN) == 0) {
+				if (ether_addr_equal(local->hw.wiphy->addresses[i].addr,
+						     sdata->vif.addr)) {
 					used = true;
 					break;
 				}
@@ -1558,8 +1558,7 @@  static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
 			val += inc;
 
 			list_for_each_entry(sdata, &local->interfaces, list) {
-				if (memcmp(tmp_addr, sdata->vif.addr,
-							ETH_ALEN) == 0) {
+				if (ether_addr_equal(tmp_addr, sdata->vif.addr)) {
 					used = true;
 					break;
 				}