mac80211: Choose a new toffset setpoint if a big tsf jump is detected. (a802a6eb) · Commits · e / devices / android_kernel_oneplus_sm8150

net/mac80211/mesh_sync.c

+20 −6

Original line number	Diff line number	Diff line
		@@ -22,7 +22,14 @@
		/* This is not in the standard. It represents a tolerable tbtt drift below
		* which we do no TSF adjustment.
		*/
		#define TBTT_MINIMUM_ADJUSTMENT 10
		#define TOFFSET_MINIMUM_ADJUSTMENT 10

		/* This is not in the standard. It represents the maximum Toffset jump above
		* which we'll invalidate the Toffset setpoint and choose a new setpoint. This
		* could be, for instance, in case a neighbor is restarted and its TSF counter
		* reset.
		* */
		#define TOFFSET_MAXIMUM_ADJUSTMENT 30000 /* 30 ms */

		struct sync_method {
		u8 method;
		@@ -156,15 +163,22 @@ static void mesh_sync_offset_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
		if (test_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN)) {
		s64 t_clockdrift = sta->t_offset_setpoint
		- sta->t_offset;

		msync_dbg("STA %pM : sta->t_offset=%lld,"
		" sta->t_offset_setpoint=%lld,"
		" t_clockdrift=%lld",
		msync_dbg("STA %pM : sta->t_offset=%lld, sta->t_offset_setpoint=%lld, t_clockdrift=%lld",
		sta->sta.addr,
		(long long) sta->t_offset,
		(long long)
		sta->t_offset_setpoint,
		(long long) t_clockdrift);

		if (t_clockdrift > TOFFSET_MAXIMUM_ADJUSTMENT \|\|
		t_clockdrift < -TOFFSET_MAXIMUM_ADJUSTMENT) {
		msync_dbg("STA %pM : t_clockdrift=%lld too large, setpoint reset",
		sta->sta.addr,
		(long long) t_clockdrift);
		clear_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN);
		goto no_sync;
		}

		rcu_read_unlock();

		spin_lock_bh(&ifmsh->sync_offset_lock);
		@@ -200,7 +214,7 @@ static void mesh_sync_offset_adjust_tbtt(struct ieee80211_sub_if_data *sdata)
		spin_lock_bh(&ifmsh->sync_offset_lock);

		if (ifmsh->sync_offset_clockdrift_max >
		TBTT_MINIMUM_ADJUSTMENT) {
		TOFFSET_MINIMUM_ADJUSTMENT) {
		/* Since ajusting the tsf here would
		* require a possibly blocking call
		* to the driver tsf setter, we punt