mac80211_hwsim: hrtimer beacon

For testing various timing-sensitive protocols (power
save, MBCA, etc.), a beacon accuracy of jiffies is not
sufficient. A tasklet_hrtimer is used for the beacon since
it runs the callback in soft-IRQ context with hrtimer
resolution.

Also handle BSS_CHANGED_BEACON_ENABLED for hwsim.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
[simplify timer container_of]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index 807d713..c54c5d1 100644 (file)
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -337,11 +337,11 @@ struct mac80211_hwsim_data {
        int scan_chan_idx;
 
        struct ieee80211_channel *channel;
-       unsigned long beacon_int; /* in jiffies unit */
+       u64 beacon_int  /* beacon interval in us */;
        unsigned int rx_filter;
        bool started, idle, scanning;
        struct mutex mutex;
-       struct timer_list beacon_timer;
+       struct tasklet_hrtimer beacon_timer;
        enum ps_mode {
                PS_DISABLED, PS_ENABLED, PS_AUTO_POLL, PS_MANUAL_POLL
        } ps;
@@ -917,7 +917,7 @@ static void mac80211_hwsim_stop(struct ieee80211_hw *hw)
 {
        struct mac80211_hwsim_data *data = hw->priv;
        data->started = false;
-       del_timer(&data->beacon_timer);
+       tasklet_hrtimer_cancel(&data->beacon_timer);
        wiphy_debug(hw->wiphy, "%s\n", __func__);
 }
 
@@ -1001,21 +1001,28 @@ static void mac80211_hwsim_beacon_tx(void *arg, u8 *mac,
                                rcu_dereference(vif->chanctx_conf)->def.chan);
 }
 
-
-static void mac80211_hwsim_beacon(unsigned long arg)
+static enum hrtimer_restart
+mac80211_hwsim_beacon(struct hrtimer *timer)
 {
-       struct ieee80211_hw *hw = (struct ieee80211_hw *) arg;
-       struct mac80211_hwsim_data *data = hw->priv;
+       struct mac80211_hwsim_data *data =
+               container_of(timer, struct mac80211_hwsim_data,
+                            beacon_timer.timer);
+       struct ieee80211_hw *hw = data->hw;
+       u64 bcn_int = data->beacon_int;
+       ktime_t next_bcn;
 
        if (!data->started)
-               return;
+               goto out;
 
        ieee80211_iterate_active_interfaces_atomic(
                hw, IEEE80211_IFACE_ITER_NORMAL,
                mac80211_hwsim_beacon_tx, hw);
 
-       data->beacon_timer.expires = jiffies + data->beacon_int;
-       add_timer(&data->beacon_timer);
+       next_bcn = ktime_add(hrtimer_get_expires(timer),
+                            ns_to_ktime(bcn_int * 1000));
+       tasklet_hrtimer_start(&data->beacon_timer, next_bcn, HRTIMER_MODE_ABS);
+out:
+       return HRTIMER_NORESTART;
 }
 
 static const char *hwsim_chantypes[] = {
@@ -1053,9 +1060,12 @@ static int mac80211_hwsim_config(struct ieee80211_hw *hw, u32 changed)
 
        data->power_level = conf->power_level;
        if (!data->started || !data->beacon_int)
-               del_timer(&data->beacon_timer);
-       else
-               mod_timer(&data->beacon_timer, jiffies + data->beacon_int);
+               tasklet_hrtimer_cancel(&data->beacon_timer);
+       else if (!hrtimer_is_queued(&data->beacon_timer.timer)) {
+               tasklet_hrtimer_start(&data->beacon_timer,
+                                     ns_to_ktime(data->beacon_int * 1000),
+                                     HRTIMER_MODE_REL);
+       }
 
        return 0;
 }
@@ -1105,12 +1115,22 @@ static void mac80211_hwsim_bss_info_changed(struct ieee80211_hw *hw,
 
        if (changed & BSS_CHANGED_BEACON_INT) {
                wiphy_debug(hw->wiphy, "  BCNINT: %d\n", info->beacon_int);
-               data->beacon_int = 1024 * info->beacon_int / 1000 * HZ / 1000;
-               if (WARN_ON(!data->beacon_int))
-                       data->beacon_int = 1;
-               if (data->started)
-                       mod_timer(&data->beacon_timer,
-                                 jiffies + data->beacon_int);
+               data->beacon_int = info->beacon_int * 1024;
+       }
+
+       if (changed & BSS_CHANGED_BEACON_ENABLED) {
+               wiphy_debug(hw->wiphy, "  BCN EN: %d\n", info->enable_beacon);
+               if (data->started &&
+                   !hrtimer_is_queued(&data->beacon_timer.timer) &&
+                   info->enable_beacon) {
+                       if (WARN_ON(!data->beacon_int))
+                               data->beacon_int = 1000 * 1024;
+                       tasklet_hrtimer_start(&data->beacon_timer,
+                                             ns_to_ktime(data->beacon_int *
+                                                         1000),
+                                             HRTIMER_MODE_REL);
+               } else if (!info->enable_beacon)
+                       tasklet_hrtimer_cancel(&data->beacon_timer);
        }
 
        if (changed & BSS_CHANGED_ERP_CTS_PROT) {
@@ -2393,8 +2413,9 @@ static int __init init_mac80211_hwsim(void)
                                                        data->debugfs, data,
                                                        &hwsim_fops_group);
 
-               setup_timer(&data->beacon_timer, mac80211_hwsim_beacon,
-                           (unsigned long) hw);
+               tasklet_hrtimer_init(&data->beacon_timer,
+                                    mac80211_hwsim_beacon,
+                                    CLOCK_REALTIME, HRTIMER_MODE_ABS);
 
                list_add_tail(&data->list, &hwsim_radios);
        }