Re: [PATCH 4/9] USB: Convert from tasklet to BH workqueue

[Allen <allen.lkml@gmail.com>]

> > The only generic interface to execute asynchronously in the BH context is
> > tasklet; however, it's marked deprecated and has some design flaws. To
> > replace tasklets, BH workqueue support was recently added. A BH workqueue
> > behaves similarly to regular workqueues except that the queued work items
> > are executed in the BH context.
> >
> > This patch converts drivers/infiniband/* from tasklet to BH workqueue.
>
> No it does not, I think your changelog is wrong :(

Whoops, sorry about that. I messed up the commit messages. I will fix it in v2.
>
> >
> > Based on the work done by Tejun Heo <tj@kernel.org>
> > Branch: https://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git for-6.10
> >
> > Signed-off-by: Allen Pais <allen.lkml@gmail.com>
> > ---
> >  drivers/usb/atm/usbatm.c            | 55 +++++++++++++++--------------
> >  drivers/usb/atm/usbatm.h            |  3 +-
> >  drivers/usb/core/hcd.c              | 22 ++++++------
> >  drivers/usb/gadget/udc/fsl_qe_udc.c | 21 +++++------
> >  drivers/usb/gadget/udc/fsl_qe_udc.h |  4 +--
> >  drivers/usb/host/ehci-sched.c       |  2 +-
> >  drivers/usb/host/fhci-hcd.c         |  3 +-
> >  drivers/usb/host/fhci-sched.c       | 10 +++---
> >  drivers/usb/host/fhci.h             |  5 +--
> >  drivers/usb/host/xhci-dbgcap.h      |  3 +-
> >  drivers/usb/host/xhci-dbgtty.c      | 15 ++++----
> >  include/linux/usb/cdc_ncm.h         |  2 +-
> >  include/linux/usb/usbnet.h          |  2 +-
> >  13 files changed, 76 insertions(+), 71 deletions(-)
> >
> > diff --git a/drivers/usb/atm/usbatm.c b/drivers/usb/atm/usbatm.c
> > index 2da6615fbb6f..74849f24e52e 100644
> > --- a/drivers/usb/atm/usbatm.c
> > +++ b/drivers/usb/atm/usbatm.c
> > @@ -17,7 +17,7 @@
> >   *           - Removed the limit on the number of devices
> >   *           - Module now autoloads on device plugin
> >   *           - Merged relevant parts of sarlib
> > - *           - Replaced the kernel thread with a tasklet
> > + *           - Replaced the kernel thread with a work
>
> a "work"?
 will fix the comments.

>
> >   *           - New packet transmission code
> >   *           - Changed proc file contents
> >   *           - Fixed all known SMP races
> > @@ -68,6 +68,7 @@
> >  #include <linux/wait.h>
> >  #include <linux/kthread.h>
> >  #include <linux/ratelimit.h>
> > +#include <linux/workqueue.h>
> >
> >  #ifdef VERBOSE_DEBUG
> >  static int usbatm_print_packet(struct usbatm_data *instance, const unsigned char *data, int len);
> > @@ -249,7 +250,7 @@ static void usbatm_complete(struct urb *urb)
> >       /* vdbg("%s: urb 0x%p, status %d, actual_length %d",
> >            __func__, urb, status, urb->actual_length); */
> >
> > -     /* Can be invoked from task context, protect against interrupts */
> > +     /* Can be invoked from work context, protect against interrupts */
>
> "workqueue"?  This too seems wrong.
>
> Same for other comment changes in this patch.

Thanks for the quick review, I will fix the comments and send out v2.

- Alle

> thanks,
>
> greg k-h
>