Merge branch 'for-3.9-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue [delayed_]work_pending() cleanups from Tejun Heo:
 "This is part of on-going cleanups to remove / minimize usages of
  workqueue interfaces which are deprecated and/or misleading.

  This round drops a number of usages of [delayed_]work_pending(), which
  are dangerous as they lack any form of synchronization and thus often
  lead to buggy / unnecessary code.  There are a couple legitimate use
  cases in kernel.  Hopefully, they can be converted and
  [delayed_]work_pending() can be removed completely.  Even if not,
  removing most of misuses should make it more difficult to find
  examples of misuses and thus slow down growth of them.

  These changes are independent from other workqueue changes."

* 'for-3.9-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  wimax/i2400m: fix i2400m->wake_tx_skb handling
  kprobes: fix wait_for_kprobe_optimizer()
  ipw2x00: simplify scan_event handling
  video/exynos: don't use [delayed_]work_pending()
  tty/max3100: don't use [delayed_]work_pending()
  x86/mce: don't use [delayed_]work_pending()
  rfkill: don't use [delayed_]work_pending()
  wl1251: don't use [delayed_]work_pending()
  thinkpad_acpi: don't use [delayed_]work_pending()
  mwifiex: don't use [delayed_]work_pending()
  sja1000: don't use [delayed_]work_pending()

13 files changed, 60 insertions, 90 deletions

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 80dbda84f1c..fc7608a89d9 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -512,11 +512,8 @@ int mce_available(struct cpuinfo_x86 *c)
 
 static void mce_schedule_work(void)
 {
-	if (!mce_ring_empty()) {
-		struct work_struct *work = &__get_cpu_var(mce_work);
-		if (!work_pending(work))
-			schedule_work(work);
-	}
+	if (!mce_ring_empty())
+		schedule_work(&__get_cpu_var(mce_work));
 }
 
 DEFINE_PER_CPU(struct irq_work, mce_irq_work);
@@ -1351,12 +1348,7 @@ int mce_notify_irq(void)
 		/* wake processes polling /dev/mcelog */
 		wake_up_interruptible(&mce_chrdev_wait);
 
-		/*
-		 * There is no risk of missing notifications because
-		 * work_pending is always cleared before the function is
-		 * executed.
-		 */
-		if (mce_helper[0] && !work_pending(&mce_trigger_work))
+		if (mce_helper[0])
 			schedule_work(&mce_trigger_work);
 
 		if (__ratelimit(&ratelimit))
diff --git a/drivers/net/can/sja1000/peak_pci.c b/drivers/net/can/sja1000/peak_pci.c
index d84888f03d9..600ac7226e5 100644
--- a/drivers/net/can/sja1000/peak_pci.c
+++ b/drivers/net/can/sja1000/peak_pci.c
@@ -339,8 +339,7 @@ static void peak_pciec_set_leds(struct peak_pciec_card *card, u8 led_mask, u8 s)
  */
 static void peak_pciec_start_led_work(struct peak_pciec_card *card)
 {
-	if (!delayed_work_pending(&card->led_work))
-		schedule_delayed_work(&card->led_work, HZ);
+	schedule_delayed_work(&card->led_work, HZ);
 }
 
 /*
diff --git a/drivers/net/wimax/i2400m/netdev.c b/drivers/net/wimax/i2400m/netdev.c
index 1d76ae855f0..530581ca019 100644
--- a/drivers/net/wimax/i2400m/netdev.c
+++ b/drivers/net/wimax/i2400m/netdev.c
@@ -156,7 +156,7 @@ void i2400m_wake_tx_work(struct work_struct *ws)
 	struct i2400m *i2400m = container_of(ws, struct i2400m, wake_tx_ws);
 	struct net_device *net_dev = i2400m->wimax_dev.net_dev;
 	struct device *dev = i2400m_dev(i2400m);
-	struct sk_buff *skb = i2400m->wake_tx_skb;
+	struct sk_buff *skb;
 	unsigned long flags;
 
 	spin_lock_irqsave(&i2400m->tx_lock, flags);
@@ -236,23 +236,26 @@ void i2400m_tx_prep_header(struct sk_buff *skb)
 void i2400m_net_wake_stop(struct i2400m *i2400m)
 {
 	struct device *dev = i2400m_dev(i2400m);
+	struct sk_buff *wake_tx_skb;
+	unsigned long flags;
 
 	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
-	/* See i2400m_hard_start_xmit(), references are taken there
-	 * and here we release them if the work was still
-	 * pending. Note we can't differentiate work not pending vs
-	 * never scheduled, so the NULL check does that. */
-	if (cancel_work_sync(&i2400m->wake_tx_ws) == 0
-	    && i2400m->wake_tx_skb != NULL) {
-		unsigned long flags;
-		struct sk_buff *wake_tx_skb;
-		spin_lock_irqsave(&i2400m->tx_lock, flags);
-		wake_tx_skb = i2400m->wake_tx_skb;	/* compat help */
-		i2400m->wake_tx_skb = NULL;	/* compat help */
-		spin_unlock_irqrestore(&i2400m->tx_lock, flags);
+	/*
+	 * See i2400m_hard_start_xmit(), references are taken there and
+	 * here we release them if the packet was still pending.
+	 */
+	cancel_work_sync(&i2400m->wake_tx_ws);
+
+	spin_lock_irqsave(&i2400m->tx_lock, flags);
+	wake_tx_skb = i2400m->wake_tx_skb;
+	i2400m->wake_tx_skb = NULL;
+	spin_unlock_irqrestore(&i2400m->tx_lock, flags);
+
+	if (wake_tx_skb) {
 		i2400m_put(i2400m);
 		kfree_skb(wake_tx_skb);
 	}
+
 	d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
 }
 
@@ -288,7 +291,7 @@ int i2400m_net_wake_tx(struct i2400m *i2400m, struct net_device *net_dev,
 	 * and if pending, release those resources. */
 	result = 0;
 	spin_lock_irqsave(&i2400m->tx_lock, flags);
-	if (!work_pending(&i2400m->wake_tx_ws)) {
+	if (!i2400m->wake_tx_skb) {
 		netif_stop_queue(net_dev);
 		i2400m_get(i2400m);
 		i2400m->wake_tx_skb = skb_get(skb);	/* transfer ref count */
diff --git a/drivers/net/wireless/ipw2x00/ipw2100.c b/drivers/net/wireless/ipw2x00/ipw2100.c
index d92b21a8e59..b3ab7b7beca 100644
--- a/drivers/net/wireless/ipw2x00/ipw2100.c
+++ b/drivers/net/wireless/ipw2x00/ipw2100.c
@@ -2181,9 +2181,10 @@ static void isr_indicate_rf_kill(struct ipw2100_priv *priv, u32 status)
 	mod_delayed_work(system_wq, &priv->rf_kill, round_jiffies_relative(HZ));
 }
 
-static void send_scan_event(void *data)
+static void ipw2100_scan_event(struct work_struct *work)
 {
-	struct ipw2100_priv *priv = data;
+	struct ipw2100_priv *priv = container_of(work, struct ipw2100_priv,
+						 scan_event.work);
 	union iwreq_data wrqu;
 
 	wrqu.data.length = 0;
@@ -2191,18 +2192,6 @@ static void send_scan_event(void *data)
 	wireless_send_event(priv->net_dev, SIOCGIWSCAN, &wrqu, NULL);
 }
 
-static void ipw2100_scan_event_later(struct work_struct *work)
-{
-	send_scan_event(container_of(work, struct ipw2100_priv,
-					scan_event_later.work));
-}
-
-static void ipw2100_scan_event_now(struct work_struct *work)
-{
-	send_scan_event(container_of(work, struct ipw2100_priv,
-					scan_event_now));
-}
-
 static void isr_scan_complete(struct ipw2100_priv *priv, u32 status)
 {
 	IPW_DEBUG_SCAN("scan complete\n");
@@ -2212,13 +2201,11 @@ static void isr_scan_complete(struct ipw2100_priv *priv, u32 status)
 
 	/* Only userspace-requested scan completion events go out immediately */
 	if (!priv->user_requested_scan) {
-		if (!delayed_work_pending(&priv->scan_event_later))
-			schedule_delayed_work(&priv->scan_event_later,
-					      round_jiffies_relative(msecs_to_jiffies(4000)));
+		schedule_delayed_work(&priv->scan_event,
+				      round_jiffies_relative(msecs_to_jiffies(4000)));
 	} else {
 		priv->user_requested_scan = 0;
-		cancel_delayed_work(&priv->scan_event_later);
-		schedule_work(&priv->scan_event_now);
+		mod_delayed_work(system_wq, &priv->scan_event, 0);
 	}
 }
 
@@ -4459,8 +4446,7 @@ static void ipw2100_kill_works(struct ipw2100_priv *priv)
 	cancel_delayed_work_sync(&priv->wx_event_work);
 	cancel_delayed_work_sync(&priv->hang_check);
 	cancel_delayed_work_sync(&priv->rf_kill);
-	cancel_work_sync(&priv->scan_event_now);
-	cancel_delayed_work_sync(&priv->scan_event_later);
+	cancel_delayed_work_sync(&priv->scan_event);
 }
 
 static int ipw2100_tx_allocate(struct ipw2100_priv *priv)
@@ -6195,8 +6181,7 @@ static struct net_device *ipw2100_alloc_device(struct pci_dev *pci_dev,
 	INIT_DELAYED_WORK(&priv->wx_event_work, ipw2100_wx_event_work);
 	INIT_DELAYED_WORK(&priv->hang_check, ipw2100_hang_check);
 	INIT_DELAYED_WORK(&priv->rf_kill, ipw2100_rf_kill);
-	INIT_WORK(&priv->scan_event_now, ipw2100_scan_event_now);
-	INIT_DELAYED_WORK(&priv->scan_event_later, ipw2100_scan_event_later);
+	INIT_DELAYED_WORK(&priv->scan_event, ipw2100_scan_event);
 
 	tasklet_init(&priv->irq_tasklet, (void (*)(unsigned long))
 		     ipw2100_irq_tasklet, (unsigned long)priv);
diff --git a/drivers/net/wireless/ipw2x00/ipw2100.h b/drivers/net/wireless/ipw2x00/ipw2100.h
index 5fe17cbab1f..c6d78790cb0 100644
--- a/drivers/net/wireless/ipw2x00/ipw2100.h
+++ b/drivers/net/wireless/ipw2x00/ipw2100.h
@@ -577,8 +577,7 @@ struct ipw2100_priv {
 	struct delayed_work wx_event_work;
 	struct delayed_work hang_check;
 	struct delayed_work rf_kill;
-	struct work_struct scan_event_now;
-	struct delayed_work scan_event_later;
+	struct delayed_work scan_event;
 
 	int user_requested_scan;
 
diff --git a/drivers/net/wireless/ipw2x00/ipw2200.c b/drivers/net/wireless/ipw2x00/ipw2200.c
index 844f201b7b7..2c2d6db0536 100644
--- a/drivers/net/wireless/ipw2x00/ipw2200.c
+++ b/drivers/net/wireless/ipw2x00/ipw2200.c
@@ -4480,18 +4480,11 @@ static void handle_scan_event(struct ipw_priv *priv)
 {
 	/* Only userspace-requested scan completion events go out immediately */
 	if (!priv->user_requested_scan) {
-		if (!delayed_work_pending(&priv->scan_event))
-			schedule_delayed_work(&priv->scan_event,
-					      round_jiffies_relative(msecs_to_jiffies(4000)));
+		schedule_delayed_work(&priv->scan_event,
+				      round_jiffies_relative(msecs_to_jiffies(4000)));
 	} else {
-		union iwreq_data wrqu;
-
 		priv->user_requested_scan = 0;
-		cancel_delayed_work(&priv->scan_event);
-
-		wrqu.data.length = 0;
-		wrqu.data.flags = 0;
-		wireless_send_event(priv->net_dev, SIOCGIWSCAN, &wrqu, NULL);
+		mod_delayed_work(system_wq, &priv->scan_event, 0);
 	}
 }
 
diff --git a/drivers/net/wireless/mwifiex/sdio.c b/drivers/net/wireless/mwifiex/sdio.c
index 5a1c1d0e559..f2874c3392b 100644
--- a/drivers/net/wireless/mwifiex/sdio.c
+++ b/drivers/net/wireless/mwifiex/sdio.c
@@ -1752,6 +1752,8 @@ mwifiex_update_mp_end_port(struct mwifiex_adapter *adapter, u16 port)
 static struct mmc_host *reset_host;
 static void sdio_card_reset_worker(struct work_struct *work)
 {
+	struct mmc_host *target = reset_host;
+
 	/* The actual reset operation must be run outside of driver thread.
 	 * This is because mmc_remove_host() will cause the device to be
 	 * instantly destroyed, and the driver then needs to end its thread,
@@ -1761,10 +1763,10 @@ static void sdio_card_reset_worker(struct work_struct *work)
 	 */
 
 	pr_err("Resetting card...\n");
-	mmc_remove_host(reset_host);
+	mmc_remove_host(target);
 	/* 20ms delay is based on experiment with sdhci controller */
 	mdelay(20);
-	mmc_add_host(reset_host);
+	mmc_add_host(target);
 }
 static DECLARE_WORK(card_reset_work, sdio_card_reset_worker);
 
@@ -1773,9 +1775,6 @@ static void mwifiex_sdio_card_reset(struct mwifiex_adapter *adapter)
 {
 	struct sdio_mmc_card *card = adapter->card;
 
-	if (work_pending(&card_reset_work))
-		return;
-
 	reset_host = card->func->card->host;
 	schedule_work(&card_reset_work);
 }
diff --git a/drivers/net/wireless/ti/wl1251/ps.c b/drivers/net/wireless/ti/wl1251/ps.c
index db719f7d269..b9e27b98bbc 100644
--- a/drivers/net/wireless/ti/wl1251/ps.c
+++ b/drivers/net/wireless/ti/wl1251/ps.c
@@ -68,8 +68,7 @@ int wl1251_ps_elp_wakeup(struct wl1251 *wl)
 	unsigned long timeout, start;
 	u32 elp_reg;
 
-	if (delayed_work_pending(&wl->elp_work))
-		cancel_delayed_work(&wl->elp_work);
+	cancel_delayed_work(&wl->elp_work);
 
 	if (!wl->elp)
 		return 0;
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index f946ca7cb76..ebcb461bb2b 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -4877,8 +4877,7 @@ static int __init light_init(struct ibm_init_struct *iibm)
 static void light_exit(void)
 {
 	led_classdev_unregister(&tpacpi_led_thinklight.led_classdev);
-	if (work_pending(&tpacpi_led_thinklight.work))
-		flush_workqueue(tpacpi_wq);
+	flush_workqueue(tpacpi_wq);
 }
 
 static int light_read(struct seq_file *m)
diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c
index 7ce3197087b..dd6277eb5a3 100644
--- a/drivers/tty/serial/max3100.c
+++ b/drivers/tty/serial/max3100.c
@@ -179,8 +179,7 @@ static void max3100_work(struct work_struct *w);
 
 static void max3100_dowork(struct max3100_port *s)
 {
-	if (!s->force_end_work && !work_pending(&s->work) &&
-	    !freezing(current) && !s->suspending)
+	if (!s->force_end_work && !freezing(current) && !s->suspending)
 		queue_work(s->workqueue, &s->work);
 }
 
diff --git a/drivers/video/exynos/exynos_dp_core.c b/drivers/video/exynos/exynos_dp_core.c
index 4ef18e2e90c..2d0d144add1 100644
--- a/drivers/video/exynos/exynos_dp_core.c
+++ b/drivers/video/exynos/exynos_dp_core.c
@@ -1121,8 +1121,7 @@ static int exynos_dp_remove(struct platform_device *pdev)
 
 	disable_irq(dp->irq);
 
-	if (work_pending(&dp->hotplug_work))
-		flush_work(&dp->hotplug_work);
+	flush_work(&dp->hotplug_work);
 
 	if (pdev->dev.of_node) {
 		if (dp->phy_addr)
@@ -1144,8 +1143,7 @@ static int exynos_dp_suspend(struct device *dev)
 	struct exynos_dp_platdata *pdata = dev->platform_data;
 	struct exynos_dp_device *dp = dev_get_drvdata(dev);
 
-	if (work_pending(&dp->hotplug_work))
-		flush_work(&dp->hotplug_work);
+	flush_work(&dp->hotplug_work);
 
 	if (dev->of_node) {
 		if (dp->phy_addr)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index f423c3ef4a8..550294d58a0 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -471,7 +471,6 @@ static LIST_HEAD(unoptimizing_list);
 
 static void kprobe_optimizer(struct work_struct *work);
 static DECLARE_DELAYED_WORK(optimizing_work, kprobe_optimizer);
-static DECLARE_COMPLETION(optimizer_comp);
 #define OPTIMIZE_DELAY 5
 
 /*
@@ -552,8 +551,7 @@ static __kprobes void do_free_cleaned_kprobes(struct list_head *free_list)
 /* Start optimizer after OPTIMIZE_DELAY passed */
 static __kprobes void kick_kprobe_optimizer(void)
 {
-	if (!delayed_work_pending(&optimizing_work))
-		schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY);
+	schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY);
 }
 
 /* Kprobe jump optimizer */
@@ -592,16 +590,25 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
 	/* Step 5: Kick optimizer again if needed */
 	if (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list))
 		kick_kprobe_optimizer();
-	else
-		/* Wake up all waiters */
-		complete_all(&optimizer_comp);
 }
 
 /* Wait for completing optimization and unoptimization */
 static __kprobes void wait_for_kprobe_optimizer(void)
 {
-	if (delayed_work_pending(&optimizing_work))
-		wait_for_completion(&optimizer_comp);
+	mutex_lock(&kprobe_mutex);
+
+	while (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list)) {
+		mutex_unlock(&kprobe_mutex);
+
+		/* this will also make optimizing_work execute immmediately */
+		flush_delayed_work(&optimizing_work);
+		/* @optimizing_work might not have been queued yet, relax */
+		cpu_relax();
+
+		mutex_lock(&kprobe_mutex);
+	}
+
+	mutex_unlock(&kprobe_mutex);
 }
 
 /* Optimize kprobe if p is ready to be optimized */
diff --git a/net/rfkill/input.c b/net/rfkill/input.c
index c9d931e7ffe..b85107b5ef6 100644
--- a/net/rfkill/input.c
+++ b/net/rfkill/input.c
@@ -148,11 +148,9 @@ static unsigned long rfkill_ratelimit(const unsigned long last)
 
 static void rfkill_schedule_ratelimited(void)
 {
-	if (delayed_work_pending(&rfkill_op_work))
-		return;
-	schedule_delayed_work(&rfkill_op_work,
-			      rfkill_ratelimit(rfkill_last_scheduled));
-	rfkill_last_scheduled = jiffies;
+	if (schedule_delayed_work(&rfkill_op_work,
+				  rfkill_ratelimit(rfkill_last_scheduled)))
+		rfkill_last_scheduled = jiffies;
 }
 
 static void rfkill_schedule_global_op(enum rfkill_sched_op op)