Hello, I am developing some userspace tools on Xen/Linux and have problems regarding the semantics of /dev/linux/evtchn. The situation is as follows: Suppose client A allocates an unbound port. Client B connects to this via bind_interdomain. Client A reads on /dev/linux/evtchn to see whether it has been notified. If client B now notifies client A, the latter gets the correct port from the call to read(). But all subsequent notifications get lost, and client A just sits there blocking on read(). Is this intended? If not, where is the problem? Regards, Julian Stecklina _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
> I am developing some userspace tools on Xen/Linux and have problems > regarding the semantics of /dev/linux/evtchn. The situation is as follows: > > Suppose client A allocates an unbound port. > Client B connects to this via bind_interdomain. > Client A reads on /dev/linux/evtchn to see whether it has been notified. > > If client B now notifies client A, the latter gets the correct port from > the call to read(). But all subsequent notifications get lost, and > client A just sits there blocking on read(). > > Is this intended? If not, where is the problem?Are you clearing the event channel after receiving the first notification? Cheers, Mark -- Dave: Just a question. What use is a unicyle with no seat? And no pedals! Mark: To answer a question with a question: What use is a skateboard? Dave: Skateboards have wheels. Mark: My wheel has a wheel! _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Mark Williamson wrote:> Are you clearing the event channel after receiving the first notification?No, but is not obvious how to do that using the ioctls provided in xen/linux/evtchn.h. IOCTL_EVTCHN_RESET seems to apply to all event channels. Regards, Julian _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Thu, Nov 16, 2006 at 02:06:34AM +0100, Julian Stecklina wrote:> Mark Williamson wrote: > > Are you clearing the event channel after receiving the first notification? > > No, but is not obvious how to do that using the ioctls provided in > xen/linux/evtchn.h. IOCTL_EVTCHN_RESET seems to apply to all event channels.Write the event channel number to the device. regards john _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel