Return-path: Received: from mail-fx0-f217.google.com ([209.85.220.217]:51121 "EHLO mail-fx0-f217.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751315AbZGaN4U (ORCPT ); Fri, 31 Jul 2009 09:56:20 -0400 Received: by fxm17 with SMTP id 17so1382697fxm.37 for ; Fri, 31 Jul 2009 06:56:18 -0700 (PDT) Subject: Re: [PATCH] mac80211: use beacons for connection monitoring From: Maxim Levitsky To: Johannes Berg Cc: Reinette Chatre , linville@tuxdriver.com, linux-wireless@vger.kernel.org In-Reply-To: <1249047576.29587.76.camel@johannes.local> References: <1248903159-17024-1-git-send-email-reinette.chatre@intel.com> <1249024097.7653.6.camel@maxim-laptop> <1249026181.29587.14.camel@johannes.local> <1249046380.6418.6.camel@maxim-laptop> <1249047576.29587.76.camel@johannes.local> Content-Type: text/plain Date: Fri, 31 Jul 2009 16:56:11 +0300 Message-Id: <1249048571.32395.6.camel@maxim-laptop> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, 2009-07-31 at 15:39 +0200, Johannes Berg wrote: > On Fri, 2009-07-31 at 16:19 +0300, Maxim Levitsky wrote: > > > First patch makes the probe requests be retried (and with it and only > > it, my connection is very stable, it never retries more that 3 times, > > and I set max retries to 5) > > > > Second patch, trivial one bumps up the timeouts (30 for ping, and 1/2 > > for response, so device won't send out frames too often) > > Thank you! > > > diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c > > index ee83125..38ef7f2 100644 > > --- a/net/mac80211/mlme.c > > +++ b/net/mac80211/mlme.c > > @@ -31,6 +31,7 @@ > > #define IEEE80211_AUTH_MAX_TRIES 3 > > #define IEEE80211_ASSOC_TIMEOUT (HZ / 5) > > #define IEEE80211_ASSOC_MAX_TRIES 3 > > +#define IEEE80211_ASSOC_RETRIES 5 > > I'd prefer that be named PROBE_TRIES or something like that? Fine > > > @@ -1209,6 +1210,7 @@ static void ieee80211_mgd_probe_ap(struct ieee80211_sub_if_data *sdata, > > ieee80211_recalc_ps(sdata->local, -1); > > mutex_unlock(&sdata->local->iflist_mtx); > > > > + sdata->u.mgd.probe_miss_count = 0; > > ssid = ieee80211_bss_get_ie(&ifmgd->associated->cbss, WLAN_EID_SSID); > > ieee80211_send_probe_req(sdata, ifmgd->associated->cbss.bssid, > > ssid + 2, ssid[1], NULL, 0); > > That appears to be in the wrong place. Shouldn't that be in the > _set_associated function? Otherwise you're always setting it to 0 before > sending the probe? I thought about this too, but I think this is the right place. ieee80211_mgd_probe_ap is called to start a probe on an AP, it will ignore following calls till ether AP responds or we reconnect. What I did is not to fail after first timeout, but resend the assoc request once more, thus this function won't be called again. > > > @@ -2072,17 +2074,36 @@ static void ieee80211_sta_work(struct work_struct *work) > > if (ifmgd->flags & (IEEE80211_STA_BEACON_POLL | > > IEEE80211_STA_CONNECTION_POLL) && > > ifmgd->associated) { > > + > > + u8 bssid[ETH_ALEN]; > > drop that empty line please no problem > > > + const u8 *ssid; > > + > > + memcpy(bssid, ifmgd->associated->cbss.bssid, ETH_ALEN); > > + > > if (time_is_after_jiffies(ifmgd->probe_timeout)) > > run_again(ifmgd, ifmgd->probe_timeout); > > - else { > > - u8 bssid[ETH_ALEN]; > > + > > + else if (ifmgd->probe_miss_count < IEEE80211_ASSOC_RETRIES) { > > + > > + printk(KERN_DEBUG "No probe response from AP %pM" > > and that one too same here > > > + " after %dms, try %d\n", bssid, > > + (1000 * IEEE80211_PROBE_WAIT)/HZ, > > + (int)ifmgd->probe_miss_count); > > + > > + ifmgd->probe_miss_count++; > > + ifmgd->probe_timeout = jiffies + IEEE80211_PROBE_WAIT; > > + run_again(ifmgd, ifmgd->probe_timeout); > > + > > + ssid = ieee80211_bss_get_ie(&ifmgd->associated->cbss, WLAN_EID_SSID); > > + ieee80211_send_probe_req(sdata, ifmgd->associated->cbss.bssid, > > + ssid + 2, ssid[1], NULL, 0); > > + } else { > > Shouldn't this just call _probe_ap() again? After you move the setting > to 0 out of it, that is? No, first of all I tried it :-). It takes the ifmgd->mtx first of all, and besides this way it is more logical, ieee80211_mgd_probe_ap is called once per AP ping, and here we continue it. Since I have copied these 3 lines from ieee80211_mgd_probe_ap I have no objection to put them in a new function. > > > From: Maxim Levitsky > > > > Do a poll every 30 seconds, and wait for response half a second > > > > Signed-off-by: Maxim Levitsky > > --- > > > > net/mac80211/mlme.c | 4 ++-- > > 1 files changed, 2 insertions(+), 2 deletions(-) > > > > > > diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c > > index 38ef7f2..a8ab40c 100644 > > --- a/net/mac80211/mlme.c > > +++ b/net/mac80211/mlme.c > > @@ -42,13 +42,13 @@ > > * Time the connection can be idle before we probe > > * it to see if we can still talk to the AP. > > */ > > -#define IEEE80211_CONNECTION_IDLE_TIME (2 * HZ) > > +#define IEEE80211_CONNECTION_IDLE_TIME (30 * HZ) > > /* > > * Time we wait for a probe response after sending > > * a probe request because of beacon loss or for > > * checking the connection still works. > > */ > > -#define IEEE80211_PROBE_WAIT (HZ / 5) > > +#define IEEE80211_PROBE_WAIT (HZ / 2) > > > Fine with me. > > johannes Best regards, Maxim Levitsky