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

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (55 commits)
  workqueue: mark init_workqueues() as early_initcall()
  workqueue: explain for_each_*cwq_cpu() iterators
  fscache: fix build on !CONFIG_SYSCTL
  slow-work: kill it
  gfs2: use workqueue instead of slow-work
  drm: use workqueue instead of slow-work
  cifs: use workqueue instead of slow-work
  fscache: drop references to slow-work
  fscache: convert operation to use workqueue instead of slow-work
  fscache: convert object to use workqueue instead of slow-work
  workqueue: fix how cpu number is stored in work->data
  workqueue: fix mayday_mask handling on UP
  workqueue: fix build problem on !CONFIG_SMP
  workqueue: fix locking in retry path of maybe_create_worker()
  async: use workqueue for worker pool
  workqueue: remove WQ_SINGLE_CPU and use WQ_UNBOUND instead
  workqueue: implement unbound workqueue
  workqueue: prepare for WQ_UNBOUND implementation
  libata: take advantage of cmwq and remove concurrency limitations
  workqueue: fix worker management invocation without pending works
  ...

Fixed up conflicts in fs/cifs/* as per Tejun. Other trivial conflicts in
include/linux/workqueue.h, kernel/trace/Kconfig and kernel/workqueue.c

11 files changed, 59 insertions, 105 deletions

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 78418ce4fc78..46cce391fa46 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -191,36 +191,11 @@ acpi_status __init acpi_os_initialize(void)
 	return AE_OK;
 }
 
-static void bind_to_cpu0(struct work_struct *work)
-{
-	set_cpus_allowed_ptr(current, cpumask_of(0));
-	kfree(work);
-}
-
-static void bind_workqueue(struct workqueue_struct *wq)
-{
-	struct work_struct *work;
-
-	work = kzalloc(sizeof(struct work_struct), GFP_KERNEL);
-	INIT_WORK(work, bind_to_cpu0);
-	queue_work(wq, work);
-}
-
 acpi_status acpi_os_initialize1(void)
 {
-	/*
-	 * On some machines, a software-initiated SMI causes corruption unless
-	 * the SMI runs on CPU 0.  An SMI can be initiated by any AML, but
-	 * typically it's done in GPE-related methods that are run via
-	 * workqueues, so we can avoid the known corruption cases by binding
-	 * the workqueues to CPU 0.
-	 */
-	kacpid_wq = create_singlethread_workqueue("kacpid");
-	bind_workqueue(kacpid_wq);
-	kacpi_notify_wq = create_singlethread_workqueue("kacpi_notify");
-	bind_workqueue(kacpi_notify_wq);
-	kacpi_hotplug_wq = create_singlethread_workqueue("kacpi_hotplug");
-	bind_workqueue(kacpi_hotplug_wq);
+	kacpid_wq = create_workqueue("kacpid");
+	kacpi_notify_wq = create_workqueue("kacpi_notify");
+	kacpi_hotplug_wq = create_workqueue("kacpi_hotplug");
 	BUG_ON(!kacpid_wq);
 	BUG_ON(!kacpi_notify_wq);
 	BUG_ON(!kacpi_hotplug_wq);
@@ -766,7 +741,14 @@ static acpi_status __acpi_os_execute(acpi_execute_type type,
 	else
 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
 
-	ret = queue_work(queue, &dpc->work);
+	/*
+	 * On some machines, a software-initiated SMI causes corruption unless
+	 * the SMI runs on CPU 0.  An SMI can be initiated by any AML, but
+	 * typically it's done in GPE-related methods that are run via
+	 * workqueues, so we can avoid the known corruption cases by always
+	 * queueing on CPU 0.
+	 */
+	ret = queue_work_on(0, queue, &dpc->work);
 
 	if (!ret) {
 		printk(KERN_ERR PREFIX
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index a0a4d6968400..4972fdf4bd31 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -98,8 +98,6 @@ static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
 
 unsigned int ata_print_id = 1;
 
-struct workqueue_struct *ata_aux_wq;
-
 struct ata_force_param {
 	const char	*name;
 	unsigned int	cbl;
@@ -5594,6 +5592,7 @@ struct ata_port *ata_port_alloc(struct ata_host *host)
 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
 #endif
 
+	mutex_init(&ap->scsi_scan_mutex);
 	INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
 	INIT_LIST_HEAD(&ap->eh_done_q);
@@ -6532,29 +6531,20 @@ static int __init ata_init(void)
 
 	ata_parse_force_param();
 
-	ata_aux_wq = create_singlethread_workqueue("ata_aux");
-	if (!ata_aux_wq)
-		goto fail;
-
 	rc = ata_sff_init();
-	if (rc)
-		goto fail;
+	if (rc) {
+		kfree(ata_force_tbl);
+		return rc;
+	}
 
 	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
 	return 0;
-
-fail:
-	kfree(ata_force_tbl);
-	if (ata_aux_wq)
-		destroy_workqueue(ata_aux_wq);
-	return rc;
 }
 
 static void __exit ata_exit(void)
 {
 	ata_sff_exit();
 	kfree(ata_force_tbl);
-	destroy_workqueue(ata_aux_wq);
 }
 
 subsys_initcall(ata_init);
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 697474b625b7..c9ae299b8342 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -727,7 +727,7 @@ void ata_scsi_error(struct Scsi_Host *host)
 	if (ap->pflags & ATA_PFLAG_LOADING)
 		ap->pflags &= ~ATA_PFLAG_LOADING;
 	else if (ap->pflags & ATA_PFLAG_SCSI_HOTPLUG)
-		queue_delayed_work(ata_aux_wq, &ap->hotplug_task, 0);
+		schedule_delayed_work(&ap->hotplug_task, 0);
 
 	if (ap->pflags & ATA_PFLAG_RECOVERED)
 		ata_port_printk(ap, KERN_INFO, "EH complete\n");
@@ -2945,7 +2945,7 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
 			ehc->i.flags |= ATA_EHI_SETMODE;
 
 			/* schedule the scsi_rescan_device() here */
-			queue_work(ata_aux_wq, &(ap->scsi_rescan_task));
+			schedule_work(&(ap->scsi_rescan_task));
 		} else if (dev->class == ATA_DEV_UNKNOWN &&
 			   ehc->tries[dev->devno] &&
 			   ata_class_enabled(ehc->classes[dev->devno])) {
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index a54273d2c3c6..d75c9c479d1a 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3435,7 +3435,7 @@ void ata_scsi_scan_host(struct ata_port *ap, int sync)
 				"                  switching to async\n");
 	}
 
-	queue_delayed_work(ata_aux_wq, &ap->hotplug_task,
+	queue_delayed_work(system_long_wq, &ap->hotplug_task,
 			   round_jiffies_relative(HZ));
 }
 
@@ -3582,6 +3582,7 @@ void ata_scsi_hotplug(struct work_struct *work)
 	}
 
 	DPRINTK("ENTER\n");
+	mutex_lock(&ap->scsi_scan_mutex);
 
 	/* Unplug detached devices.  We cannot use link iterator here
 	 * because PMP links have to be scanned even if PMP is
@@ -3595,6 +3596,7 @@ void ata_scsi_hotplug(struct work_struct *work)
 	/* scan for new ones */
 	ata_scsi_scan_host(ap, 0);
 
+	mutex_unlock(&ap->scsi_scan_mutex);
 	DPRINTK("EXIT\n");
 }
 
@@ -3673,9 +3675,7 @@ static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
  *	@work: Pointer to ATA port to perform scsi_rescan_device()
  *
  *	After ATA pass thru (SAT) commands are executed successfully,
- *	libata need to propagate the changes to SCSI layer.  This
- *	function must be executed from ata_aux_wq such that sdev
- *	attach/detach don't race with rescan.
+ *	libata need to propagate the changes to SCSI layer.
  *
  *	LOCKING:
  *	Kernel thread context (may sleep).
@@ -3688,6 +3688,7 @@ void ata_scsi_dev_rescan(struct work_struct *work)
 	struct ata_device *dev;
 	unsigned long flags;
 
+	mutex_lock(&ap->scsi_scan_mutex);
 	spin_lock_irqsave(ap->lock, flags);
 
 	ata_for_each_link(link, ap, EDGE) {
@@ -3707,6 +3708,7 @@ void ata_scsi_dev_rescan(struct work_struct *work)
 	}
 
 	spin_unlock_irqrestore(ap->lock, flags);
+	mutex_unlock(&ap->scsi_scan_mutex);
 }
 
 /**
diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index efa4a18cfb9d..674c1436491f 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -3318,14 +3318,7 @@ void ata_sff_port_init(struct ata_port *ap)
 
 int __init ata_sff_init(void)
 {
-	/*
-	 * FIXME: In UP case, there is only one workqueue thread and if you
-	 * have more than one PIO device, latency is bloody awful, with
-	 * occasional multi-second "hiccups" as one PIO device waits for
-	 * another.  It's an ugly wart that users DO occasionally complain
-	 * about; luckily most users have at most one PIO polled device.
-	 */
-	ata_sff_wq = create_workqueue("ata_sff");
+	ata_sff_wq = alloc_workqueue("ata_sff", WQ_RESCUER, WQ_MAX_ACTIVE);
 	if (!ata_sff_wq)
 		return -ENOMEM;
 
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 4b84ed60324a..9ce1ecc63e39 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -54,7 +54,6 @@ enum {
 };
 
 extern unsigned int ata_print_id;
-extern struct workqueue_struct *ata_aux_wq;
 extern int atapi_passthru16;
 extern int libata_fua;
 extern int libata_noacpi;
diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index 11fe9c870d17..45981304feb8 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -831,13 +831,11 @@ int drm_helper_resume_force_mode(struct drm_device *dev)
 }
 EXPORT_SYMBOL(drm_helper_resume_force_mode);
 
-static struct slow_work_ops output_poll_ops;
-
 #define DRM_OUTPUT_POLL_PERIOD (10*HZ)
-static void output_poll_execute(struct slow_work *work)
+static void output_poll_execute(struct work_struct *work)
 {
-	struct delayed_slow_work *delayed_work = container_of(work, struct delayed_slow_work, work);
-	struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_slow_work);
+	struct delayed_work *delayed_work = to_delayed_work(work);
+	struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
 	struct drm_connector *connector;
 	enum drm_connector_status old_status, status;
 	bool repoll = false, changed = false;
@@ -877,7 +875,7 @@ static void output_poll_execute(struct slow_work *work)
 	}
 
 	if (repoll) {
-		ret = delayed_slow_work_enqueue(delayed_work, DRM_OUTPUT_POLL_PERIOD);
+		ret = queue_delayed_work(system_nrt_wq, delayed_work, DRM_OUTPUT_POLL_PERIOD);
 		if (ret)
 			DRM_ERROR("delayed enqueue failed %d\n", ret);
 	}
@@ -887,7 +885,7 @@ void drm_kms_helper_poll_disable(struct drm_device *dev)
 {
 	if (!dev->mode_config.poll_enabled)
 		return;
-	delayed_slow_work_cancel(&dev->mode_config.output_poll_slow_work);
+	cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
 }
 EXPORT_SYMBOL(drm_kms_helper_poll_disable);
 
@@ -903,7 +901,7 @@ void drm_kms_helper_poll_enable(struct drm_device *dev)
 	}
 
 	if (poll) {
-		ret = delayed_slow_work_enqueue(&dev->mode_config.output_poll_slow_work, DRM_OUTPUT_POLL_PERIOD);
+		ret = queue_delayed_work(system_nrt_wq, &dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);
 		if (ret)
 			DRM_ERROR("delayed enqueue failed %d\n", ret);
 	}
@@ -912,9 +910,7 @@ EXPORT_SYMBOL(drm_kms_helper_poll_enable);
 
 void drm_kms_helper_poll_init(struct drm_device *dev)
 {
-	slow_work_register_user(THIS_MODULE);
-	delayed_slow_work_init(&dev->mode_config.output_poll_slow_work,
-			       &output_poll_ops);
+	INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
 	dev->mode_config.poll_enabled = true;
 
 	drm_kms_helper_poll_enable(dev);
@@ -924,7 +920,6 @@ EXPORT_SYMBOL(drm_kms_helper_poll_init);
 void drm_kms_helper_poll_fini(struct drm_device *dev)
 {
 	drm_kms_helper_poll_disable(dev);
-	slow_work_unregister_user(THIS_MODULE);
 }
 EXPORT_SYMBOL(drm_kms_helper_poll_fini);
 
@@ -932,12 +927,8 @@ void drm_helper_hpd_irq_event(struct drm_device *dev)
 {
 	if (!dev->mode_config.poll_enabled)
 		return;
-	delayed_slow_work_cancel(&dev->mode_config.output_poll_slow_work);
-	/* schedule a slow work asap */
-	delayed_slow_work_enqueue(&dev->mode_config.output_poll_slow_work, 0);
+	/* kill timer and schedule immediate execution, this doesn't block */
+	cancel_delayed_work(&dev->mode_config.output_poll_work);
+	queue_delayed_work(system_nrt_wq, &dev->mode_config.output_poll_work, 0);
 }
 EXPORT_SYMBOL(drm_helper_hpd_irq_event);
-
-static struct slow_work_ops output_poll_ops = {
-	.execute = output_poll_execute,
-};
diff --git a/drivers/media/video/ivtv/ivtv-driver.c b/drivers/media/video/ivtv/ivtv-driver.c
index 90daa6e751d8..07c5c18a25cb 100644
--- a/drivers/media/video/ivtv/ivtv-driver.c
+++ b/drivers/media/video/ivtv/ivtv-driver.c
@@ -705,6 +705,8 @@ done:
  */
 static int __devinit ivtv_init_struct1(struct ivtv *itv)
 {
+	struct sched_param param = { .sched_priority = 99 };
+
 	itv->base_addr = pci_resource_start(itv->pdev, 0);
 	itv->enc_mbox.max_mbox = 2; /* the encoder has 3 mailboxes (0-2) */
 	itv->dec_mbox.max_mbox = 1; /* the decoder has 2 mailboxes (0-1) */
@@ -716,13 +718,17 @@ static int __devinit ivtv_init_struct1(struct ivtv *itv)
 	spin_lock_init(&itv->lock);
 	spin_lock_init(&itv->dma_reg_lock);
 
-	itv->irq_work_queues = create_singlethread_workqueue(itv->v4l2_dev.name);
-	if (itv->irq_work_queues == NULL) {
-		IVTV_ERR("Could not create ivtv workqueue\n");
+	init_kthread_worker(&itv->irq_worker);
+	itv->irq_worker_task = kthread_run(kthread_worker_fn, &itv->irq_worker,
+					   itv->v4l2_dev.name);
+	if (IS_ERR(itv->irq_worker_task)) {
+		IVTV_ERR("Could not create ivtv task\n");
 		return -1;
 	}
+	/* must use the FIFO scheduler as it is realtime sensitive */
+	sched_setscheduler(itv->irq_worker_task, SCHED_FIFO, &param);
 
-	INIT_WORK(&itv->irq_work_queue, ivtv_irq_work_handler);
+	init_kthread_work(&itv->irq_work, ivtv_irq_work_handler);
 
 	/* start counting open_id at 1 */
 	itv->open_id = 1;
@@ -1006,7 +1012,7 @@ static int __devinit ivtv_probe(struct pci_dev *pdev,
 	/* PCI Device Setup */
 	retval = ivtv_setup_pci(itv, pdev, pci_id);
 	if (retval == -EIO)
-		goto free_workqueue;
+		goto free_worker;
 	if (retval == -ENXIO)
 		goto free_mem;
 
@@ -1218,8 +1224,8 @@ free_mem:
 	release_mem_region(itv->base_addr + IVTV_REG_OFFSET, IVTV_REG_SIZE);
 	if (itv->has_cx23415)
 		release_mem_region(itv->base_addr + IVTV_DECODER_OFFSET, IVTV_DECODER_SIZE);
-free_workqueue:
-	destroy_workqueue(itv->irq_work_queues);
+free_worker:
+	kthread_stop(itv->irq_worker_task);
 err:
 	if (retval == 0)
 		retval = -ENODEV;
@@ -1363,9 +1369,9 @@ static void ivtv_remove(struct pci_dev *pdev)
 	ivtv_set_irq_mask(itv, 0xffffffff);
 	del_timer_sync(&itv->dma_timer);
 
-	/* Stop all Work Queues */
-	flush_workqueue(itv->irq_work_queues);
-	destroy_workqueue(itv->irq_work_queues);
+	/* Kill irq worker */
+	flush_kthread_worker(&itv->irq_worker);
+	kthread_stop(itv->irq_worker_task);
 
 	ivtv_streams_cleanup(itv, 1);
 	ivtv_udma_free(itv);
diff --git a/drivers/media/video/ivtv/ivtv-driver.h b/drivers/media/video/ivtv/ivtv-driver.h
index bd084df4448a..102071246218 100644
--- a/drivers/media/video/ivtv/ivtv-driver.h
+++ b/drivers/media/video/ivtv/ivtv-driver.h
@@ -51,7 +51,7 @@
 #include <linux/unistd.h>
 #include <linux/pagemap.h>
 #include <linux/scatterlist.h>
-#include <linux/workqueue.h>
+#include <linux/kthread.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <asm/uaccess.h>
@@ -260,7 +260,6 @@ struct ivtv_mailbox_data {
 #define IVTV_F_I_DEC_PAUSED	   20 	/* the decoder is paused */
 #define IVTV_F_I_INITED		   21 	/* set after first open */
 #define IVTV_F_I_FAILED		   22 	/* set if first open failed */
-#define IVTV_F_I_WORK_INITED       23	/* worker thread was initialized */
 
 /* Event notifications */
 #define IVTV_F_I_EV_DEC_STOPPED	   28	/* decoder stopped event */
@@ -666,8 +665,9 @@ struct ivtv {
 	/* Interrupts & DMA */
 	u32 irqmask;                    /* active interrupts */
 	u32 irq_rr_idx;                 /* round-robin stream index */
-	struct workqueue_struct *irq_work_queues;       /* workqueue for PIO/YUV/VBI actions */
-	struct work_struct irq_work_queue;              /* work entry */
+	struct kthread_worker irq_worker;		/* kthread worker for PIO/YUV/VBI actions */
+	struct task_struct *irq_worker_task;		/* task for irq_worker */
+	struct kthread_work irq_work;	/* kthread work entry */
 	spinlock_t dma_reg_lock;        /* lock access to DMA engine registers */
 	int cur_dma_stream;		/* index of current stream doing DMA (-1 if none) */
 	int cur_pio_stream;		/* index of current stream doing PIO (-1 if none) */
diff --git a/drivers/media/video/ivtv/ivtv-irq.c b/drivers/media/video/ivtv/ivtv-irq.c
index fea1ec33b0df..9b4faf009196 100644
--- a/drivers/media/video/ivtv/ivtv-irq.c
+++ b/drivers/media/video/ivtv/ivtv-irq.c
@@ -71,19 +71,10 @@ static void ivtv_pio_work_handler(struct ivtv *itv)
 	write_reg(IVTV_IRQ_ENC_PIO_COMPLETE, 0x44);
 }
 
-void ivtv_irq_work_handler(struct work_struct *work)
+void ivtv_irq_work_handler(struct kthread_work *work)
 {
-	struct ivtv *itv = container_of(work, struct ivtv, irq_work_queue);
+	struct ivtv *itv = container_of(work, struct ivtv, irq_work);
 
-	DEFINE_WAIT(wait);
-
-	if (test_and_clear_bit(IVTV_F_I_WORK_INITED, &itv->i_flags)) {
-		struct sched_param param = { .sched_priority = 99 };
-
-		/* This thread must use the FIFO scheduler as it
-		   is realtime sensitive. */
-		sched_setscheduler(current, SCHED_FIFO, &param);
-	}
 	if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags))
 		ivtv_pio_work_handler(itv);
 
@@ -975,7 +966,7 @@ irqreturn_t ivtv_irq_handler(int irq, void *dev_id)
 	}
 
 	if (test_and_clear_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags)) {
-		queue_work(itv->irq_work_queues, &itv->irq_work_queue);
+		queue_kthread_work(&itv->irq_worker, &itv->irq_work);
 	}
 
 	spin_unlock(&itv->dma_reg_lock);
diff --git a/drivers/media/video/ivtv/ivtv-irq.h b/drivers/media/video/ivtv/ivtv-irq.h
index f879a5822e71..1e84433737cc 100644
--- a/drivers/media/video/ivtv/ivtv-irq.h
+++ b/drivers/media/video/ivtv/ivtv-irq.h
@@ -46,7 +46,7 @@
 
 irqreturn_t ivtv_irq_handler(int irq, void *dev_id);
 
-void ivtv_irq_work_handler(struct work_struct *work);
+void ivtv_irq_work_handler(struct kthread_work *work);
 void ivtv_dma_stream_dec_prepare(struct ivtv_stream *s, u32 offset, int lock);
 void ivtv_unfinished_dma(unsigned long arg);