On Tue, Jan 31, 2012 at 06:56:01PM +0100, Michel Dänzer wrote: > On Die, 2012-01-31 at 16:59 +0000, Simon Farnsworth wrote: > > Userspace currently busywaits for fences to complete; on my workload, this > > busywait consumes 10% of the available CPU time. > > > > Provide an ioctl so that userspace can wait for an EOP interrupt that > > corresponds to a previous EVENT_WRITE_EOP. > > > > Signed-off-by: Simon Farnsworth <simon.farnsworth@xxxxxxxxxxxx> > > --- > > I've been working on top of Jerome's tiling patches, so this doesn't apply > > directly on top of current upstream kernels. I can easily rebase to another > > version upon request - just point me to a git tree. > > > > My goal is to remove the sched_yield in Mesa's r600_fence_finish given up to > > date enough kernel; I hope, though, that the interface is clean enough for > > other users to extend it in the future (e.g. using compute rings). > > I'm afraid not: Unless I'm missing something, userspace can't know which > ring the kernel submitted the CS to, and the kernel can't guess which > ring userspace needs to wait for. iirc the plan was to add a return value to cs ioctl and add an ioctl to allow to wait on this return value. ie allowing userspace to wait on specific submited cs. Cheers, Jerome _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
