| Message ID | 20211018174508.2137279-8-matthew.auld@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/9] drm/i915: mark dmabuf objects as ALLOC_USER | expand |
On Mon, 2021-10-18 at 18:45 +0100, Matthew Auld wrote: > While the pages can't be swapped out, they can be discarded by the > shrinker. > Normally such objects are marked with __I915_MADV_PURGED, which can't > be > unset, and therefore requires a new object. For kernel internal > objects > this is not true, since the madv hint is reset for our special > volatile > objects, such that we can re-acquire new pages, if so desired, > without > needing a new object. As a result we should probably be paranoid here > and put the object back into the CPU domain when discarding the > pages, > and also correctly set cache_dirty, if required. > > Signed-off-by: Matthew Auld <matthew.auld@intel.com> > Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> > --- > drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 ++ > 1 file changed, 2 insertions(+) Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_internal.c b/drivers/gpu/drm/i915/gem/i915_gem_internal.c index e5ae9c06510c..a57a6b7013c2 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_internal.c @@ -134,6 +134,8 @@ static void i915_gem_object_put_pages_internal(struct drm_i915_gem_object *obj, internal_free_pages(pages); obj->mm.dirty = false; + + __start_cpu_write(obj); } static const struct drm_i915_gem_object_ops i915_gem_object_internal_ops = {
While the pages can't be swapped out, they can be discarded by the shrinker. Normally such objects are marked with __I915_MADV_PURGED, which can't be unset, and therefore requires a new object. For kernel internal objects this is not true, since the madv hint is reset for our special volatile objects, such that we can re-acquire new pages, if so desired, without needing a new object. As a result we should probably be paranoid here and put the object back into the CPU domain when discarding the pages, and also correctly set cache_dirty, if required. Signed-off-by: Matthew Auld <matthew.auld@intel.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> --- drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 ++ 1 file changed, 2 insertions(+)