leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

usb: gadget: uvc: increase worker prio to WQ_HIGHPRI

Browse Source 
This patch is changing the simple workqueue in the gadget driver to be
allocated as async_wq with a higher priority. The pump worker, that is
filling the usb requests, will have a higher priority and will not be
scheduled away so often while the video stream is handled. This will
lead to fewer streaming underruns.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Link: https://lore.kernel.org/r/20220907215818.2670097-1-m.grzeschik@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Michael Grzeschik 2022-09-07 23:58:18 +02:00 committed by Greg Kroah-Hartman
parent d818320ea2
commit 9b91a65230
4 changed files with 13 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/usb/gadget/function/f_uvc.c
View File

@ -897,10 +897,14 @@ static void uvc_function_unbind(struct usb_configuration *c,
{
struct usb_composite_dev *cdev = c->cdev;
struct uvc_device *uvc = to_uvc(f);
struct uvc_video *video = &uvc->video;
long wait_ret = 1;
uvcg_info(f, "%s()\n", __func__);
if (video->async_wq)
destroy_workqueue(video->async_wq);
/*
* If we know we're connected via v4l2, then there should be a cleanup
* of the device from userspace either via UVC_EVENT_DISCONNECT or

1
drivers/usb/gadget/function/uvc.h
View File

@ -88,6 +88,7 @@ struct uvc_video {
struct usb_ep *ep;
struct work_struct pump;
struct workqueue_struct *async_wq;
/* Frame parameters */
u8 bpp;

2
drivers/usb/gadget/function/uvc_v4l2.c
View File

@ -170,7 +170,7 @@ uvc_v4l2_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
return ret;
if (uvc->state == UVC_STATE_STREAMING)
schedule_work(&video->pump);
queue_work(video->async_wq, &video->pump);
return ret;
}

9
drivers/usb/gadget/function/uvc_video.c
View File

@ -277,7 +277,7 @@ uvc_video_complete(struct usb_ep *ep, struct usb_request *req)
spin_unlock_irqrestore(&video->req_lock, flags);
if (uvc->state == UVC_STATE_STREAMING)
schedule_work(&video->pump);
queue_work(video->async_wq, &video->pump);
}
static int
@ -485,7 +485,7 @@ int uvcg_video_enable(struct uvc_video *video, int enable)
video->req_int_count = 0;
schedule_work(&video->pump);
queue_work(video->async_wq, &video->pump);
return ret;
}
@ -499,6 +499,11 @@ int uvcg_video_init(struct uvc_video *video, struct uvc_device *uvc)
spin_lock_init(&video->req_lock);
INIT_WORK(&video->pump, uvcg_video_pump);
/* Allocate a work queue for asynchronous video pump handler. */
video->async_wq = alloc_workqueue("uvcgadget", WQ_UNBOUND | WQ_HIGHPRI, 0);
if (!video->async_wq)
return -EINVAL;
video->uvc = uvc;
video->fcc = V4L2_PIX_FMT_YUYV;
video->bpp = 16;