Sharing graphics contexts is not the same thing as allowing two completely different device drivers access to the hardware on VT swap. Two different device drivers may have completely different contents in all of the registers, CP running or not, VRAM and AGP space. With two device drivers you have to completely save state of the GPU, VRAM and AGP at VT swap in order to be safe.
I would like to see a single device drver always controlling the GPU and VRAM/AGP memory management. Then it is easy to switch graphics contexts on VT swap. --- Alan Cox <[EMAIL PROTECTED]> wrote: > On Iau, 2004-05-06 at 20:57, Jon Smirl wrote: > > Simple example, DRM starts GPU coprocessor running. VT swap happens. New > user > > stops coprocessor. VT swap back to DRM. Now DRM thinks it left the > coprocessor > > running but that's not true now. DRM and FB conflict when FB is using the > > coprocessor for accelerated text. > > FB already has mode switch context waits, so does DRM. And you don't > want to break direct access to registers for most things because its > a performance consideration of high importance. > > > Timesharing device drivers on the graphics > > hardware at VT swap is a very broken design. > > Read Mark Kilgards SGI papers - they were doing context > management at scheduling level.. > > > > ------------------------------------------------------- > This SF.Net email is sponsored by Sleepycat Software > Learn developer strategies Cisco, Motorola, Ericsson & Lucent use to > deliver higher performing products faster, at low TCO. > http://www.sleepycat.com/telcomwpreg.php?From=osdnemail3 > _______________________________________________ > Mesa3d-dev mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/mesa3d-dev ===== Jon Smirl [EMAIL PROTECTED] __________________________________ Do you Yahoo!? Win a $20,000 Career Makeover at Yahoo! HotJobs http://hotjobs.sweepstakes.yahoo.com/careermakeover ------------------------------------------------------- This SF.Net email is sponsored by Sleepycat Software Learn developer strategies Cisco, Motorola, Ericsson & Lucent use to deliver higher performing products faster, at low TCO. http://www.sleepycat.com/telcomwpreg.php?From=osdnemail3 -- _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
