Re: weird Xwayland and compositor deadlock issue [WAS: [PATCH xserver v2] xwayland: handle EAGAIN and EINTR gracefully]

2016-09-19 Thread Daniel Stone
Hi, On 17 September 2016 at 08:21, Jasper St. Pierre wrote: > Daniel suggested that timestamps *should* be on the same timebase. > Currently, they are not. X11 server timestamps are > CLOCK_MONOTONIC_COARSE-based and are calculated at delivery time, evdev > timestamps are

Re: weird Xwayland and compositor deadlock issue [WAS: [PATCH xserver v2] xwayland: handle EAGAIN and EINTR gracefully]

2016-09-19 Thread Pekka Paalanen
On Fri, 16 Sep 2016 22:21:42 -0700 "Jasper St. Pierre" wrote: > Hi, > > Based on my reading of the spec, writing an ICCCM-compliant WM *requires* > blocking, since the behavior of an UnmapNotify depends on the attributes of > a window. We cannot process any X11 events

Re: weird Xwayland and compositor deadlock issue [WAS: [PATCH xserver v2] xwayland: handle EAGAIN and EINTR gracefully]

2016-09-16 Thread Jasper St. Pierre
Hi, Based on my reading of the spec, writing an ICCCM-compliant WM *requires* blocking, since the behavior of an UnmapNotify depends on the attributes of a window. We cannot process any X11 events while we are retrieving the attributes of a mapped window inside MapRequest. If we want to modify

Re: weird Xwayland and compositor deadlock issue [WAS: [PATCH xserver v2] xwayland: handle EAGAIN and EINTR gracefully]

2016-09-14 Thread Pekka Paalanen
On Tue, 13 Sep 2016 12:04:14 -0400 (EDT) Olivier Fourdan wrote: > Hi Pekka, > > - Original Message - > > Hi Olivier, > > > > I don't have any solution for you. The interactions between the Wayland > > compositor and Xwayland are known to be very easily deadlockable

Re: weird Xwayland and compositor deadlock issue [WAS: [PATCH xserver v2] xwayland: handle EAGAIN and EINTR gracefully]

2016-09-13 Thread Adam Jackson
On Tue, 2016-09-13 at 06:13 -0400, Olivier Fourdan wrote: > I tried to poll() the Wayland fd with a timeout prior to > wl_display_flush() to make sure to wl_display_flush() only when > writable, to see if that would help unblocking mutter waiting for its > PropertyNotify event but that did not

Re: weird Xwayland and compositor deadlock issue [WAS: [PATCH xserver v2] xwayland: handle EAGAIN and EINTR gracefully]

2016-09-13 Thread Olivier Fourdan
Hi Pekka, - Original Message - > Hi Olivier, > > I don't have any solution for you. The interactions between the Wayland > compositor and Xwayland are known to be very easily deadlockable IIRC. I > believe the only thing you can do is ensure no such case can ever > occur, which is very

Re: weird Xwayland and compositor deadlock issue [WAS: [PATCH xserver v2] xwayland: handle EAGAIN and EINTR gracefully]

2016-09-13 Thread Olivier Fourdan
Hi all - Original Message - > wl_display_flush() can fail with EAGAIN and Xwayland would make this a > fatal error. > > Handle the usual EAGAIN and EINTR gracefully so that Xwayland doesn't > die for so little. Right, I am running out of ideas... So the approach of using poll() to wait