Date: Mon, 22 Feb 2016 19:39:46 +0200 From: "Andriy Voskoboinyk" <avos@freebsd.org> To: "Adrian Chadd" <adrian.chadd@gmail.com>, "freebsd-wireless@freebsd.org" <freebsd-wireless@freebsd.org> Subject: Re: net80211 inactivity processing Message-ID: <op.yc8wokei4dikkl@localhost> In-Reply-To: <CAJ-Vmo=aN%2BP4AUfzDbek0ExuLi_-hhxNJJTP2NNpAkgwqV8NyA@mail.gmail.com> References: <op.yc7k7mh34dikkl@localhost> <CAJ-Vmo=aN%2BP4AUfzDbek0ExuLi_-hhxNJJTP2NNpAkgwqV8NyA@mail.gmail.com>
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Mon, 22 Feb 2016 03:43:51 +0200 було написано Adrian Chadd <adrian.chadd@gmail.com>: Because control frames are disabled by default? (the timer is refreshed every time when a frame goes into input path (ni->ni_inact = ni->ni_inact_reload)). This may be added to TX callback (already implemented in https://reviews.freebsd.org/D5147); however, I have no idea what to do with > drivers that lie about frame completion/failure > Hi, > > I think it is a hold-over from how node reclaimation used to work. > Sending null data frames to probe if a station is still there is a > common thing to do. So yeah, maybe we should go figure out why the > inactivity timer isn't kicked if the NULL data frame succeeds (ie, the > driver explicitly gives us ACK feedback, rather than drivers that lie > about frame completion/failure.) > > > > -adrian > > > On 21 February 2016 at 16:34, Andriy Voskoboinyk <avos@freebsd.org> > wrote: >> Hi, >> >> What is the purpose of the following code? (especially in HOSTAP mode) >> (ieee80211_node.c): >> >> static void >> ieee80211_timeout_stations(struct ieee80211com *ic) >> { >> struct ieee80211_node_table *nt = &ic->ic_sta; >> struct ieee80211vap *vap; >> struct ieee80211_node *ni; >> int gen = 0; >> >> IEEE80211_NODE_ITERATE_LOCK(nt); >> gen = ++nt->nt_scangen; >> restart: >> IEEE80211_NODE_LOCK(nt); >> TAILQ_FOREACH(ni, &nt->nt_node, ni_list) { >> ... >> if ((vap->iv_flags_ext & IEEE80211_FEXT_INACT) >> && >> (0 < ni->ni_inact && >> ni->ni_inact <= vap->iv_inact_probe) && >> ni->ni_rates.rs_nrates != 0) { >> IEEE80211_NOTE(vap, >> IEEE80211_MSG_INACT | >> IEEE80211_MSG_NODE, >> ni, "%s", >> "probe station due to inactivity"); >> /* >> * Grab a reference before unlocking the >> table >> * so the node cannot be reclaimed >> before we >> * send the frame. >> ieee80211_send_nulldata >> * understands we've done this and >> reclaims >> the >> * ref for us as needed. >> */ >> ieee80211_ref_node(ni); >> IEEE80211_NODE_UNLOCK(nt); >> ieee80211_send_nulldata(ni); >> <<< >> here >> /* XXX stat? */ >> goto restart; >> } >> ... >> } >> IEEE80211_NODE_UNLOCK(nt); >> >> IEEE80211_NODE_ITERATE_UNLOCK(nt); >> } >> >> As for me, ieee80211_send_nulldata() will not refresh ni->ni_inact, >> nor will trigger any data transmission from the STA (so, it does >> nothing?). >> _______________________________________________ >> freebsd-wireless@freebsd.org mailing list >> https://lists.freebsd.org/mailman/listinfo/freebsd-wireless >> To unsubscribe, send any mail to >> "freebsd-wireless-unsubscribe@freebsd.org"
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