[02/35] ivtv: use kthread_worker instead of workqueue
Commit Message
Upcoming workqueue updates will no longer guarantee fixed workqueue to
worker kthread association, so giving RT priority to the irq worker
won't work. Use kthread_worker which guarantees specific kthread
association instead. This also makes setting the priority cleaner.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Andy Walls <awalls@md.metrocast.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: ivtv-devel@ivtvdriver.org
Cc: linux-media@vger.kernel.org
---
drivers/media/video/ivtv/ivtv-driver.c | 26 ++++++++++++++++----------
drivers/media/video/ivtv/ivtv-driver.h | 8 ++++----
drivers/media/video/ivtv/ivtv-irq.c | 15 +++------------
drivers/media/video/ivtv/ivtv-irq.h | 2 +-
4 files changed, 24 insertions(+), 27 deletions(-)
Comments
On Mon, 2010-06-28 at 23:03 +0200, Tejun Heo wrote:
> Upcoming workqueue updates will no longer guarantee fixed workqueue to
> worker kthread association, so giving RT priority to the irq worker
> won't work. Use kthread_worker which guarantees specific kthread
> association instead. This also makes setting the priority cleaner.
>
> Signed-off-by: Tejun Heo <tj@kernel.org>
> Cc: Andy Walls <awalls@md.metrocast.net>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: ivtv-devel@ivtvdriver.org
> Cc: linux-media@vger.kernel.org
Assuming the new kthread_worker implementation is OK, this change for
ivtv looks good.
Reviewed-by: Andy Walls <awalls@md.metrocast.net>
Acked-by: Andy Walls <awalls@md.metrocast.net>
Regards,
Andy
> drivers/media/video/ivtv/ivtv-driver.c | 26 ++++++++++++++++----------
> drivers/media/video/ivtv/ivtv-driver.h | 8 ++++----
> drivers/media/video/ivtv/ivtv-irq.c | 15 +++------------
> drivers/media/video/ivtv/ivtv-irq.h | 2 +-
> 4 files changed, 24 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/media/video/ivtv/ivtv-driver.c b/drivers/media/video/ivtv/ivtv-driver.c
> index 1b79475..49e0b1c 100644
> --- a/drivers/media/video/ivtv/ivtv-driver.c
> +++ b/drivers/media/video/ivtv/ivtv-driver.c
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
On 07/05/2010 07:11 PM, Andy Walls wrote:
> Assuming the new kthread_worker implementation is OK, this change for
> ivtv looks good.
>
> Reviewed-by: Andy Walls <awalls@md.metrocast.net>
> Acked-by: Andy Walls <awalls@md.metrocast.net>
May I route this patch through wq branch? As it's not clear how this
whole patchset will end up, I think it would be better to keep things
isolated in this branch.
Thank you.
On Tue, 2010-07-06 at 09:01 +0200, Tejun Heo wrote:
> On 07/05/2010 07:11 PM, Andy Walls wrote:
> > Assuming the new kthread_worker implementation is OK, this change for
> > ivtv looks good.
> >
> > Reviewed-by: Andy Walls <awalls@md.metrocast.net>
> > Acked-by: Andy Walls <awalls@md.metrocast.net>
>
> May I route this patch through wq branch? As it's not clear how this
> whole patchset will end up, I think it would be better to keep things
> isolated in this branch.
Yes, I think that is the best way to do things.
Regards,
Andy
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
@@ -695,6 +695,8 @@ 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) */
@@ -706,13 +708,17 @@ 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, ¶m);
- 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;
@@ -996,7 +1002,7 @@ 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;
@@ -1208,8 +1214,8 @@ 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;
@@ -1353,9 +1359,9 @@ 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);
@@ -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>
@@ -257,7 +257,6 @@ 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 */
@@ -663,8 +662,9 @@ 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) */
@@ -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, ¶m);
- }
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);
@@ -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);