mainlining shenanigans
5a90606df7
obj->pin_global was originally used as a means to keep the shrinker off the active scanout, but we use the vma->pin_count itself for that and the obj->frontbuffer to delay shrinking active framebuffers. The other role that obj->pin_global gained was for spotting display objects inside GEM and working harder to keep those coherent; for which we can again simply inspect obj->frontbuffer directly. Coming up next, we will want to manipulate the pin_global counter outside of the principle locks, so would need to make pin_global atomic. However, since obj->frontbuffer is already managed atomically, it makes sense to use that the primary key for display objects instead of having pin_global. Ville pointed out the principle difference is that obj->frontbuffer is set for as long as an intel_framebuffer is attached to an object, but obj->pin_global was only raised for as long as the object was active. In practice, this means that we consider the object as being on the scanout for longer than is strictly required, causing us to be more proactive in flushing -- though it should be true that we would have flushed eventually when the back became the front, except that on the flip path that flush is async but when hit from another ioctl it will be synchronous. v2: i915_gem_object_is_framebuffer() Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190902040303.14195-5-chris@chris-wilson.co.uk |
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| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.