diff mbox

rc80211_minstrel: fix contention window calculation

Message ID 20090916022430.27557.93510.stgit@mj.roinet.com (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Pavel Roskin Sept. 16, 2009, 2:24 a.m. UTC
The contention window is supposed to be a power of two minus one, i.e.
15, 31, 63, 127...  minstrel_rate_init() forgets to subtract 1, so the
sequence becomes 15, 32, 66, 134...

Bug reported by Dan Halperin <dhalperi@cs.washington.edu>

Signed-off-by: Pavel Roskin <proski@gnu.org>
---
 net/mac80211/rc80211_minstrel.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

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diff mbox

Patch

diff --git a/net/mac80211/rc80211_minstrel.c b/net/mac80211/rc80211_minstrel.c
index 7c51429..6e5d68b 100644
--- a/net/mac80211/rc80211_minstrel.c
+++ b/net/mac80211/rc80211_minstrel.c
@@ -418,7 +418,7 @@  minstrel_rate_init(void *priv, struct ieee80211_supported_band *sband,
 
 			/* contention window */
 			tx_time_single += t_slot + min(cw, mp->cw_max);
-			cw = (cw + 1) << 1;
+			cw = (cw << 1) | 1;
 
 			tx_time += tx_time_single;
 			tx_time_cts += tx_time_single + mi->sp_ack_dur;