mac80211: fix multi-use timer
We have, sometimes, multiple things that want to
run but don't have their own timer. Introduce a
new function to mac80211's mlme run_again() that
makes sure that the timer will run again at the
_first_ needed time, use that function and also
properly reprogram the timer once it fired.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 8e4a604..c1114bb 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -72,6 +72,26 @@
WARN_ON(!mutex_is_locked(&ifmgd->mtx));
}
+/*
+ * We can have multiple work items (and connection probing)
+ * scheduling this timer, but we need to take care to only
+ * reschedule it when it should fire _earlier_ than it was
+ * asked for before, or if it's not pending right now. This
+ * function ensures that. Note that it then is required to
+ * run this function for all timeouts after the first one
+ * has happened -- the work that runs from this timer will
+ * do that.
+ */
+static void run_again(struct ieee80211_if_managed *ifmgd,
+ unsigned long timeout)
+{
+ ASSERT_MGD_MTX(ifmgd);
+
+ if (!timer_pending(&ifmgd->timer) ||
+ time_before(timeout, ifmgd->timer.expires))
+ mod_timer(&ifmgd->timer, timeout);
+}
+
static int ecw2cw(int ecw)
{
return (1 << ecw) - 1;
@@ -916,7 +936,7 @@
ieee80211_send_probe_req(sdata, NULL, wk->ssid, wk->ssid_len, NULL, 0);
wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
- mod_timer(&ifmgd->timer, wk->timeout);
+ run_again(ifmgd, wk->timeout);
return RX_MGMT_NONE;
}
@@ -958,7 +978,7 @@
wk->auth_transaction = 2;
wk->timeout = jiffies + IEEE80211_AUTH_TIMEOUT;
- mod_timer(&ifmgd->timer, wk->timeout);
+ run_again(ifmgd, wk->timeout);
return RX_MGMT_NONE;
}
@@ -1079,7 +1099,7 @@
ieee80211_send_assoc(sdata, wk);
wk->timeout = jiffies + IEEE80211_ASSOC_TIMEOUT;
- mod_timer(&ifmgd->timer, wk->timeout);
+ run_again(ifmgd, wk->timeout);
return RX_MGMT_NONE;
}
@@ -1140,7 +1160,7 @@
ieee80211_send_probe_req(sdata, ifmgd->associated->cbss.bssid,
ssid + 2, ssid[1], NULL, 0);
- mod_timer(&ifmgd->timer, jiffies + IEEE80211_PROBE_WAIT);
+ run_again(ifmgd, jiffies + IEEE80211_PROBE_WAIT);
out:
mutex_unlock(&ifmgd->mtx);
}
@@ -1350,8 +1370,7 @@
sdata->dev->name, tu, ms);
wk->timeout = jiffies + msecs_to_jiffies(ms);
if (ms > IEEE80211_ASSOC_TIMEOUT)
- mod_timer(&ifmgd->timer,
- jiffies + msecs_to_jiffies(ms));
+ run_again(ifmgd, jiffies + msecs_to_jiffies(ms));
return RX_MGMT_NONE;
}
@@ -1981,8 +2000,15 @@
}
list_for_each_entry_safe(wk, tmp, &ifmgd->work_list, list) {
- if (time_before(jiffies, wk->timeout))
+ if (time_is_after_jiffies(wk->timeout)) {
+ /*
+ * This work item isn't supposed to be worked on
+ * right now, but take care to adjust the timer
+ * properly.
+ */
+ run_again(ifmgd, wk->timeout);
continue;
+ }
switch (wk->state) {
default: