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a1e969e033
This originally started as a patch from Bernard as a way of simply setting the VS scheduler. After submitting the RFC patch, we decided to also modify the DS scheduler. To be most explicit, I've made the patch explicitly set all scheduler modes, and included the defines for other modes (in case someone feels frisky later). The rest of the story gets a bit weird. The first version of the patch showed an almost unbelievable performance improvement. Since rebasing my branch it appears the performance improvement has gone, unfortunately. But setting these bits seem to be the right thing to do given that the docs describe corruption that can occur with the default settings. In summary, I am seeing no more perf improvements (or regressions) in my limited testing, but we believe this should be set to prevent rendering corruption, therefore cc stable. v1: Clear bit 4 also (Ken + Eugeni) Do a full clear + set of the bits we want (Me). Cc: Bernard Kilarski <bernard.r.kilarski@intel.com> Cc: stable <stable@vger.kernel.org> Reviewed-by (RFC): Kenneth Graunke <kenneth@whitecape.org> Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com> Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com> Reviewed-by: Kenneth Graunke <kenneth@whitecape.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
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The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).
The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:
1. The DRM provides synchronized access to the graphics hardware via
the use of an optimized two-tiered lock.
2. The DRM enforces the DRI security policy for access to the graphics
hardware by only allowing authenticated X11 clients access to
restricted regions of memory.
3. The DRM provides a generic DMA engine, complete with multiple
queues and the ability to detect the need for an OpenGL context
switch.
4. The DRM is extensible via the use of small device-specific modules
that rely extensively on the API exported by the DRM module.
Documentation on the DRI is available from:
http://dri.freedesktop.org/wiki/Documentation
http://sourceforge.net/project/showfiles.php?group_id=387
http://dri.sourceforge.net/doc/
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://dri.sourceforge.net/doc/drm_low_level.html
Hardware Locking for the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/hardware_locking_low_level.html
A Security Analysis of the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/security_low_level.html