linux/linux-stable.git - Linux kernel stable tree

Age	Commit message (Collapse)	Author
2020-10-18	drm/i915: use vmap in shmem_pin_map	Christoph Hellwig
	shmem_pin_map somewhat awkwardly reimplements vmap using alloc_vm_area and manual pte setup. The only practical difference is that alloc_vm_area prefeaults the vmalloc area PTEs, which doesn't seem to be required here (and could be added to vmap using a flag if actually required). Switch to use vmap, and use vfree to free both the vmalloc mapping and the page array, as well as dropping the references to each page. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Juergen Gross <jgross@suse.com> Cc: Matthew Auld <matthew.auld@intel.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Link: https://lkml.kernel.org/r/20201002122204.1534411-7-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-29	drm/i915/gt: Keep a no-frills swappable copy of the default context state	Chris Wilson
	We need to keep the default context state around to instantiate new contexts (aka golden rendercontext), and we also keep it pinned while the engine is active so that we can quickly reset a hanging context. However, the default contexts are large enough to merit keeping in swappable memory as opposed to kernel memory, so we store them inside shmemfs. Currently, we use the normal GEM objects to create the default context image, but we can throw away all but the shmemfs file. This greatly simplifies the tricky power management code which wants to run underneath the normal GT locking, and we definitely do not want to use any high level objects that may appear to recurse back into the GT. Though perhaps the primary advantage of the complex GEM object is that we aggressively cache the mapping, but here we are recreating the vm_area everytime time we unpark. At the worst, we add a lightweight cache, but first find a microbenchmark that is impacted. Having started to create some utility functions to make working with shmemfs objects easier, we can start putting them to wider use, where GEM objects are overkill, such as storing persistent error state. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Ramalingam C <ramalingam.c@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200429172429.6054-1-chris@chris-wilson.co.uk