On Thursday 04 November 2010 21:11:38 Matthew Fleming wrote: > On Thu, Nov 4, 2010 at 12:11 PM, Hans Petter Selasky <hsela...@c2i.net> wrote: > > On Thursday 04 November 2010 20:01:57 Matthew Fleming wrote: > >> On Thu, Nov 4, 2010 at 11:41 AM, Hans Petter Selasky <hsela...@c2i.net> > > > > wrote: > >> > On Thursday 04 November 2010 15:29:51 John Baldwin wrote: > >> >> (and there is in Jeff's OFED branch) > >> > > >> > Is there a link to this branch? I would certainly have a look at his > >> > work and re-base my patch. > >> > >> It's on svn.freebsd.org: > >> > >> http://svn.freebsd.org/viewvc/base/projects/ofed/head/sys/kern/subr_task > >> que ue.c?view=log > >> http://svn.freebsd.org/viewvc/base?view=revision&revision=209422 > >> > >> For the purpose of speed, I'm not opposed to breaking the KBI by using > >> a doubly-linked TAILQ, but I don't think the difference will matter > >> all that often (perhaps I'm wrong and some taskqueues have dozens of > >> pending tasks?) > >> > >> Thanks, > >> matthew > > > > At first look I see that I need a non-blocking version of: > > > > taskqueue_cancel( > > > > At the point in the code where these functions are called I cannot block. > > Is this impossible to implement? > > It depends on whether the queue uses a MTX_SPIN or MTX_DEF. It is not > possible to determine whether a task is running without taking the > taskqueue lock. And it is certainly impossible to dequeue a task > without the lock that was used to enqueue it. > > However, a variant that dequeued if the task was still pending, and > returned failure otherwise (rather than sleeping) is definitely > possible.
I think that if a task is currently executing, then there should be a drain method for that. I.E. two methods: One to stop and one to cancel/drain. Can you implement this? --HPS _______________________________________________ firstname.lastname@example.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-usb To unsubscribe, send any mail to "freebsd-usb-unsubscr...@freebsd.org"