[PATCH 13/16] drm/i915: Remove pinned check from madvise ioctl

Chris Wilson
2016-08-01T18:23:07Z

We don't need to incur the overhead of checking whether the object is
pinned prior to changing its madvise. If the object is pinned, the
madvise will not take effect until it is unpinned and so we cannot free
the pages being pointed at by hardware. Marking a pinned object with
allocated pages as DONTNEED will not trigger any undue warnings. The check
is therefore superfluous, and by removing it we can remove a linear walk
over all the vma the object has.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/i915/i915_gem.c | 6 ------
1 file changed, 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 51ec5cd1c6ca..4b8a391912bc 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3853,11 +3853,6 @@ i915_gem_madvise_ioctl(struct drm_device *dev, void *data,
goto unlock;
}

- if (i915_gem_obj_is_pinned(obj)) {
- ret = -EINVAL;
- goto out;
- }
-
if (obj->pages &&
obj->tiling_mode != I915_TILING_NONE &&
dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
@@ -3876,7 +3871,6 @@ i915_gem_madvise_ioctl(struct drm_device *dev, void *data,

args->retained = obj->madv != __I915_MADV_PURGED;

-out:
i915_gem_object_put(obj);
unlock:
mutex_unlock(&dev->struct_mutex);
--
2.8.1