This is a note to let you know that I've just added the patch titled
wifi: cfg80211: Add wiphy_delayed_work_pending()
to the 6.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
wifi-cfg80211-add-wiphy_delayed_work_pending.patch
and it can be found in the queue-6.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 36924fe0511098cbca6d5aaaec65648a9be10998
Author: Remi Pommarel <repk@xxxxxxxxxxxx>
Date: Tue Sep 24 21:28:04 2024 +0200
wifi: cfg80211: Add wiphy_delayed_work_pending()
[ Upstream commit 68d0021fe7231eec0fb84cd110cf62a6e782b72d ]
Add wiphy_delayed_work_pending() to check if any delayed work timer is
pending, that can be used to be sure that wiphy_delayed_work_queue()
won't postpone an already pending delayed work.
Signed-off-by: Remi Pommarel <repk@xxxxxxxxxxxx>
Link: https://patch.msgid.link/20240924192805.13859-2-repk@xxxxxxxxxxxx
[fix return value kernel-doc]
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 192d72c8b4654..702653448d2fc 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -6129,6 +6129,50 @@ void wiphy_delayed_work_cancel(struct wiphy *wiphy,
void wiphy_delayed_work_flush(struct wiphy *wiphy,
struct wiphy_delayed_work *dwork);
+/**
+ * wiphy_delayed_work_pending - Find out whether a wiphy delayable
+ * work item is currently pending.
+ *
+ * @wiphy: the wiphy, for debug purposes
+ * @dwork: the delayed work in question
+ *
+ * Return: true if timer is pending, false otherwise
+ *
+ * How wiphy_delayed_work_queue() works is by setting a timer which
+ * when it expires calls wiphy_work_queue() to queue the wiphy work.
+ * Because wiphy_delayed_work_queue() uses mod_timer(), if it is
+ * called twice and the second call happens before the first call
+ * deadline, the work will rescheduled for the second deadline and
+ * won't run before that.
+ *
+ * wiphy_delayed_work_pending() can be used to detect if calling
+ * wiphy_work_delayed_work_queue() would start a new work schedule
+ * or delayed a previous one. As seen below it cannot be used to
+ * detect precisely if the work has finished to execute nor if it
+ * is currently executing.
+ *
+ * CPU0 CPU1
+ * wiphy_delayed_work_queue(wk)
+ * mod_timer(wk->timer)
+ * wiphy_delayed_work_pending(wk) -> true
+ *
+ * [...]
+ * expire_timers(wk->timer)
+ * detach_timer(wk->timer)
+ * wiphy_delayed_work_pending(wk) -> false
+ * wk->timer->function() |
+ * wiphy_work_queue(wk) | delayed work pending
+ * list_add_tail() | returns false but
+ * queue_work(cfg80211_wiphy_work) | wk->func() has not
+ * | been run yet
+ * [...] |
+ * cfg80211_wiphy_work() |
+ * wk->func() V
+ *
+ */
+bool wiphy_delayed_work_pending(struct wiphy *wiphy,
+ struct wiphy_delayed_work *dwork);
+
/**
* enum ieee80211_ap_reg_power - regulatory power for an Access Point
*
diff --git a/net/wireless/core.c b/net/wireless/core.c
index c9ebf9449fcc3..b2b512923ecee 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -1705,6 +1705,13 @@ void wiphy_delayed_work_flush(struct wiphy *wiphy,
}
EXPORT_SYMBOL_GPL(wiphy_delayed_work_flush);
+bool wiphy_delayed_work_pending(struct wiphy *wiphy,
+ struct wiphy_delayed_work *dwork)
+{
+ return timer_pending(&dwork->timer);
+}
+EXPORT_SYMBOL_GPL(wiphy_delayed_work_pending);
+
static int __init cfg80211_init(void)
{
int err;
