redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

drm/i915: Choose not to evict faultable objects from the GGTT

Browse source 
Often times we do not want to evict mapped objects from the GGTT as
these are quite expensive to teardown and frequently reused (causing an
equally, if not more so, expensive setup). In particular, when faulting
in a new object we want to avoid evicting an active object, or else we
may trigger a page-fault-of-doom as we ping-pong between evicting two
objects.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160818161718.27187-26-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2016-08-18 17:17:05 +01:00
parent 50349247ea
commit 821188778b
3 changed files with 16 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
drivers/gpu/drm/i915/i915_gem.c
View file

@ -1706,6 +1706,7 @@ int i915_gem_fault(struct vm_area_struct *area, struct vm_fault *vmf)
struct i915_vma *vma;
pgoff_t page_offset;
unsigned long pfn;
unsigned int flags;
int ret;
/* We don't use vmf->pgoff since that has the fake offset */
@ -1735,9 +1736,16 @@ int i915_gem_fault(struct vm_area_struct *area, struct vm_fault *vmf)
goto err_unlock;
}
/* If the object is smaller than a couple of partial vma, it is
* not worth only creating a single partial vma - we may as well
* clear enough space for the full object.
*/
flags = PIN_MAPPABLE;
if (obj->base.size > 2 * MIN_CHUNK_PAGES << PAGE_SHIFT)
flags |= PIN_NONBLOCK | PIN_NONFAULT;
/* Now pin it into the GTT as needed */
vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
PIN_MAPPABLE | PIN_NONBLOCK);
vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, flags);
if (IS_ERR(vma)) {
struct i915_ggtt_view view;
unsigned int chunk_size;

7
drivers/gpu/drm/i915/i915_gem_evict.c
View file

@ -47,7 +47,7 @@ gpu_is_idle(struct drm_i915_private *dev_priv)
}
static bool
mark_free(struct i915_vma *vma, struct list_head *unwind)
mark_free(struct i915_vma *vma, unsigned int flags, struct list_head *unwind)
{
if (i915_vma_is_pinned(vma))
return false;
@ -55,6 +55,9 @@ mark_free(struct i915_vma *vma, struct list_head *unwind)
if (WARN_ON(!list_empty(&vma->exec_list)))
return false;
if (flags & PIN_NONFAULT && vma->obj->fault_mappable)
return false;
list_add(&vma->exec_list, unwind);
return drm_mm_scan_add_block(&vma->node);
}
@ -129,7 +132,7 @@ search_again:
phase = phases;
do {
list_for_each_entry(vma, *phase, vm_link)
if (mark_free(vma, &eviction_list))
if (mark_free(vma, flags, &eviction_list))
goto found;
} while (*++phase);

1
drivers/gpu/drm/i915/i915_gem_gtt.h
View file

@ -637,6 +637,7 @@ void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj);
#define PIN_NONBLOCK BIT(0)
#define PIN_MAPPABLE BIT(1)
#define PIN_ZONE_4G BIT(2)
#define PIN_NONFAULT BIT(3)
#define PIN_MBZ BIT(5) /* I915_VMA_PIN_OVERFLOW */
#define PIN_GLOBAL BIT(6) /* I915_VMA_GLOBAL_BIND */