public inbox for linux-wireless@vger.kernel.org
 help / color / mirror / Atom feed
From: Johannes Berg <johannes@sipsolutions.net>
To: John Linville <linville@tuxdriver.com>
Cc: linux-wireless <linux-wireless@vger.kernel.org>
Subject: [PATCH] mac80211: sequence number micro-optimisation
Date: Mon, 10 Aug 2009 16:02:40 +0200	[thread overview]
Message-ID: <1249912960.32614.5.camel@johannes.local> (raw)

There's no need to mask the variable with 0xFFF0
since we ever only use it as a u16 and the lowest
four bits can't ever be non-zero. The compiler
cannot infer the latter, and therefore has to emit
code to do the masking.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
---
 net/mac80211/tx.c |    1 -
 1 file changed, 1 deletion(-)

--- wireless-testing.orig/net/mac80211/tx.c	2009-08-10 13:34:45.000000000 +0200
+++ wireless-testing/net/mac80211/tx.c	2009-08-10 13:34:58.000000000 +0200
@@ -700,7 +700,6 @@ ieee80211_tx_h_sequence(struct ieee80211
 		/* for pure STA mode without beacons, we can do it */
 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
 		tx->sdata->sequence_number += 0x10;
-		tx->sdata->sequence_number &= IEEE80211_SCTL_SEQ;
 		return TX_CONTINUE;
 	}
 



                 reply	other threads:[~2009-08-10 14:03 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1249912960.32614.5.camel@johannes.local \
    --to=johannes@sipsolutions.net \
    --cc=linux-wireless@vger.kernel.org \
    --cc=linville@tuxdriver.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox