From 41f63c5359d14ca995172b8f6eaffd93f60fec54 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 3 Aug 2012 10:30:47 -0700 Subject: workqueue: use mod_delayed_work() instead of cancel + queue Convert delayed_work users doing cancel_delayed_work() followed by queue_delayed_work() to mod_delayed_work(). Most conversions are straight-forward. Ones worth mentioning are, * drivers/edac/edac_mc.c: edac_mc_workq_setup() converted to always use mod_delayed_work() and cancel loop in edac_mc_reset_delay_period() is dropped. * drivers/platform/x86/thinkpad_acpi.c: No need to remember whether watchdog is active or not. @fan_watchdog_active and related code dropped. * drivers/power/charger-manager.c: Seemingly a lot of delayed_work_pending() abuse going on here. [delayed_]work_pending() are unsynchronized and racy when used like this. I converted one instance in fullbatt_handler(). Please conver the rest so that it invokes workqueue APIs for the intended target state rather than trying to game work item pending state transitions. e.g. if timer should be modified - call mod_delayed_work(), canceled - call cancel_delayed_work[_sync](). * drivers/thermal/thermal_sys.c: thermal_zone_device_set_polling() simplified. Note that round_jiffies() calls in this function are meaningless. round_jiffies() work on absolute jiffies not delta delay used by delayed_work. v2: Tomi pointed out that __cancel_delayed_work() users can't be safely converted to mod_delayed_work(). They could be calling it from irq context and if that happens while delayed_work_timer_fn() is running, it could deadlock. __cancel_delayed_work() users are dropped. Signed-off-by: Tejun Heo Acked-by: Henrique de Moraes Holschuh Acked-by: Dmitry Torokhov Acked-by: Anton Vorontsov Acked-by: David Howells Cc: Tomi Valkeinen Cc: Jens Axboe Cc: Jiri Kosina Cc: Doug Thompson Cc: David Airlie Cc: Roland Dreier Cc: "John W. Linville" Cc: Zhang Rui Cc: Len Brown Cc: "J. Bruce Fields" Cc: Johannes Berg --- fs/afs/vlocation.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) (limited to 'fs/afs/vlocation.c') diff --git a/fs/afs/vlocation.c b/fs/afs/vlocation.c index 431984d2e372..57bcb1596530 100644 --- a/fs/afs/vlocation.c +++ b/fs/afs/vlocation.c @@ -561,12 +561,7 @@ static void afs_vlocation_reaper(struct work_struct *work) if (expiry > now) { delay = (expiry - now) * HZ; _debug("delay %lu", delay); - if (!queue_delayed_work(afs_wq, &afs_vlocation_reap, - delay)) { - cancel_delayed_work(&afs_vlocation_reap); - queue_delayed_work(afs_wq, &afs_vlocation_reap, - delay); - } + mod_delayed_work(afs_wq, &afs_vlocation_reap, delay); break; } @@ -614,13 +609,10 @@ void afs_vlocation_purge(void) spin_lock(&afs_vlocation_updates_lock); list_del_init(&afs_vlocation_updates); spin_unlock(&afs_vlocation_updates_lock); - cancel_delayed_work(&afs_vlocation_update); - queue_delayed_work(afs_vlocation_update_worker, - &afs_vlocation_update, 0); + mod_delayed_work(afs_vlocation_update_worker, &afs_vlocation_update, 0); destroy_workqueue(afs_vlocation_update_worker); - cancel_delayed_work(&afs_vlocation_reap); - queue_delayed_work(afs_wq, &afs_vlocation_reap, 0); + mod_delayed_work(afs_wq, &afs_vlocation_reap, 0); } /* -- cgit v1.2.3-58-ga151