Re: [RFC 3/3] EHCI: handle late isochronous submissions

2013-08-29 Thread Alan Stern
On Thu, 29 Aug 2013, Ming Lei wrote: > On Wed, 28 Aug 2013 12:23:31 -0400 (EDT) > Alan Stern wrote: > > > You must never alter ehci->last_iso_frame like this. It violates the > > driver's invariants for time to run "backward". After all, there may > > already be other TDs scheduled for the f

Re: [RFC 3/3] EHCI: handle late isochronous submissions

2013-08-28 Thread Ming Lei
On Wed, 28 Aug 2013 12:23:31 -0400 (EDT) Alan Stern wrote: > You must never alter ehci->last_iso_frame like this. It violates the > driver's invariants for time to run "backward". After all, there may > already be other TDs scheduled for the frames you are about to scan > again; they mustn't

Re: [RFC 3/3] EHCI: handle late isochronous submissions

2013-08-28 Thread Ming Lei
On Thu, Aug 29, 2013 at 12:23 AM, Alan Stern wrote: > On Wed, 28 Aug 2013, Ming Lei wrote: > >> Below is the approach I proposed(mentioned in another thread), which should >> be >> simper than this one, any comments? >> >> drivers/usb/host/ehci-sched.c | 53 >>

Re: [RFC 3/3] EHCI: handle late isochronous submissions

2013-08-28 Thread Alan Stern
On Wed, 28 Aug 2013, Ming Lei wrote: > Below is the approach I proposed(mentioned in another thread), which should be > simper than this one, any comments? > > drivers/usb/host/ehci-sched.c | 53 > ++--- > drivers/usb/host/ehci.h |1 + > 2 files c

Re: [RFC 3/3] EHCI: handle late isochronous submissions

2013-08-28 Thread Ming Lei
On Mon, 26 Aug 2013 14:50:53 -0400 (EDT) Alan Stern wrote: > This patch does the real work. It fixes up ehci-hcd so that an URB > submitted by a completion handler will keep the isochronous stream > alive, even if the handler was delayed by running in a tasklet and the > queue has emptied out