linux/drivers/gpu/drm/i915/i915_gem_evict.c
Chris Wilson cd377ea93f drm/i915: Implement fair lru eviction across both rings. (v2)
Based in a large part upon Daniel Vetter's implementation and adapted
for handling multiple rings in a single pass.

This should lead to better gtt usage and fixes the page-fault-of-doom
triggered. The fairness is provided by scanning through the GTT space
amalgamating space in rendering order. As soon as we have a contiguous
space in the GTT large enough for the new object (and its alignment),
evict any object which lies within that space. This should keep more
objects resident in the GTT.

Doing throughput testing on a PineView machine with cairo-perf-trace
indicates that there is very little difference with the new LRU scan,
perhaps a small improvement... Except oddly for the poppler trace.

Reference:

  Bug 15911 - Intermittent X crash (freeze)
  https://bugzilla.kernel.org/show_bug.cgi?id=15911

  Bug 20152 - cannot view JPG in firefox when running UXA
  https://bugs.freedesktop.org/show_bug.cgi?id=20152

  Bug 24369 - Hang when scrolling firefox page with window in front
  https://bugs.freedesktop.org/show_bug.cgi?id=24369

  Bug 28478 - Intermittent graphics lockups due to overflow/loop
  https://bugs.freedesktop.org/show_bug.cgi?id=28478

v2: Attempt to clarify the logic and order of eviction through the use
of comments and macros.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Eric Anholt <eric@anholt.net>
2010-08-09 11:24:32 -07:00

272 lines
8.1 KiB
C

/*
* Copyright © 2008-2010 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* Authors:
* Eric Anholt <eric@anholt.net>
* Chris Wilson <chris@chris-wilson.co.uuk>
*
*/
#include "drmP.h"
#include "drm.h"
#include "i915_drv.h"
#include "i915_drm.h"
static struct drm_i915_gem_object *
i915_gem_next_active_object(struct drm_device *dev,
struct list_head **render_iter,
struct list_head **bsd_iter)
{
drm_i915_private_t *dev_priv = dev->dev_private;
struct drm_i915_gem_object *render_obj = NULL, *bsd_obj = NULL;
if (*render_iter != &dev_priv->render_ring.active_list)
render_obj = list_entry(*render_iter,
struct drm_i915_gem_object,
list);
if (HAS_BSD(dev)) {
if (*bsd_iter != &dev_priv->bsd_ring.active_list)
bsd_obj = list_entry(*bsd_iter,
struct drm_i915_gem_object,
list);
if (render_obj == NULL) {
*bsd_iter = (*bsd_iter)->next;
return bsd_obj;
}
if (bsd_obj == NULL) {
*render_iter = (*render_iter)->next;
return render_obj;
}
/* XXX can we handle seqno wrapping? */
if (render_obj->last_rendering_seqno < bsd_obj->last_rendering_seqno) {
*render_iter = (*render_iter)->next;
return render_obj;
} else {
*bsd_iter = (*bsd_iter)->next;
return bsd_obj;
}
} else {
*render_iter = (*render_iter)->next;
return render_obj;
}
}
static bool
mark_free(struct drm_i915_gem_object *obj_priv,
struct list_head *unwind)
{
list_add(&obj_priv->evict_list, unwind);
return drm_mm_scan_add_block(obj_priv->gtt_space);
}
#define i915_for_each_active_object(OBJ, R, B) \
*(R) = dev_priv->render_ring.active_list.next; \
*(B) = dev_priv->bsd_ring.active_list.next; \
while (((OBJ) = i915_gem_next_active_object(dev, (R), (B))) != NULL)
int
i915_gem_evict_something(struct drm_device *dev, int min_size, unsigned alignment)
{
drm_i915_private_t *dev_priv = dev->dev_private;
struct list_head eviction_list, unwind_list;
struct drm_i915_gem_object *obj_priv, *tmp_obj_priv;
struct list_head *render_iter, *bsd_iter;
int ret = 0;
i915_gem_retire_requests(dev);
/* Re-check for free space after retiring requests */
if (drm_mm_search_free(&dev_priv->mm.gtt_space,
min_size, alignment, 0))
return 0;
/*
* The goal is to evict objects and amalgamate space in LRU order.
* The oldest idle objects reside on the inactive list, which is in
* retirement order. The next objects to retire are those on the (per
* ring) active list that do not have an outstanding flush. Once the
* hardware reports completion (the seqno is updated after the
* batchbuffer has been finished) the clean buffer objects would
* be retired to the inactive list. Any dirty objects would be added
* to the tail of the flushing list. So after processing the clean
* active objects we need to emit a MI_FLUSH to retire the flushing
* list, hence the retirement order of the flushing list is in
* advance of the dirty objects on the active lists.
*
* The retirement sequence is thus:
* 1. Inactive objects (already retired)
* 2. Clean active objects
* 3. Flushing list
* 4. Dirty active objects.
*
* On each list, the oldest objects lie at the HEAD with the freshest
* object on the TAIL.
*/
INIT_LIST_HEAD(&unwind_list);
drm_mm_init_scan(&dev_priv->mm.gtt_space, min_size, alignment);
/* First see if there is a large enough contiguous idle region... */
list_for_each_entry(obj_priv, &dev_priv->mm.inactive_list, list) {
if (mark_free(obj_priv, &unwind_list))
goto found;
}
/* Now merge in the soon-to-be-expired objects... */
i915_for_each_active_object(obj_priv, &render_iter, &bsd_iter) {
/* Does the object require an outstanding flush? */
if (obj_priv->base.write_domain || obj_priv->pin_count)
continue;
if (mark_free(obj_priv, &unwind_list))
goto found;
}
/* Finally add anything with a pending flush (in order of retirement) */
list_for_each_entry(obj_priv, &dev_priv->mm.flushing_list, list) {
if (obj_priv->pin_count)
continue;
if (mark_free(obj_priv, &unwind_list))
goto found;
}
i915_for_each_active_object(obj_priv, &render_iter, &bsd_iter) {
if (! obj_priv->base.write_domain || obj_priv->pin_count)
continue;
if (mark_free(obj_priv, &unwind_list))
goto found;
}
/* Nothing found, clean up and bail out! */
list_for_each_entry(obj_priv, &unwind_list, evict_list) {
ret = drm_mm_scan_remove_block(obj_priv->gtt_space);
BUG_ON(ret);
}
/* We expect the caller to unpin, evict all and try again, or give up.
* So calling i915_gem_evict_everything() is unnecessary.
*/
return -ENOSPC;
found:
INIT_LIST_HEAD(&eviction_list);
list_for_each_entry_safe(obj_priv, tmp_obj_priv,
&unwind_list, evict_list) {
if (drm_mm_scan_remove_block(obj_priv->gtt_space)) {
/* drm_mm doesn't allow any other other operations while
* scanning, therefore store to be evicted objects on a
* temporary list. */
list_move(&obj_priv->evict_list, &eviction_list);
}
}
/* Unbinding will emit any required flushes */
list_for_each_entry_safe(obj_priv, tmp_obj_priv,
&eviction_list, evict_list) {
#if WATCH_LRU
DRM_INFO("%s: evicting %p\n", __func__, obj);
#endif
ret = i915_gem_object_unbind(&obj_priv->base);
if (ret)
return ret;
}
/* The just created free hole should be on the top of the free stack
* maintained by drm_mm, so this BUG_ON actually executes in O(1).
* Furthermore all accessed data has just recently been used, so it
* should be really fast, too. */
BUG_ON(!drm_mm_search_free(&dev_priv->mm.gtt_space, min_size,
alignment, 0));
return 0;
}
int
i915_gem_evict_everything(struct drm_device *dev)
{
drm_i915_private_t *dev_priv = dev->dev_private;
int ret;
bool lists_empty;
spin_lock(&dev_priv->mm.active_list_lock);
lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
list_empty(&dev_priv->mm.flushing_list) &&
list_empty(&dev_priv->render_ring.active_list) &&
(!HAS_BSD(dev)
|| list_empty(&dev_priv->bsd_ring.active_list)));
spin_unlock(&dev_priv->mm.active_list_lock);
if (lists_empty)
return -ENOSPC;
/* Flush everything (on to the inactive lists) and evict */
ret = i915_gpu_idle(dev);
if (ret)
return ret;
BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
ret = i915_gem_evict_inactive(dev);
if (ret)
return ret;
spin_lock(&dev_priv->mm.active_list_lock);
lists_empty = (list_empty(&dev_priv->mm.inactive_list) &&
list_empty(&dev_priv->mm.flushing_list) &&
list_empty(&dev_priv->render_ring.active_list) &&
(!HAS_BSD(dev)
|| list_empty(&dev_priv->bsd_ring.active_list)));
spin_unlock(&dev_priv->mm.active_list_lock);
BUG_ON(!lists_empty);
return 0;
}
/** Unbinds all inactive objects. */
int
i915_gem_evict_inactive(struct drm_device *dev)
{
drm_i915_private_t *dev_priv = dev->dev_private;
while (!list_empty(&dev_priv->mm.inactive_list)) {
struct drm_gem_object *obj;
int ret;
obj = &list_first_entry(&dev_priv->mm.inactive_list,
struct drm_i915_gem_object,
list)->base;
ret = i915_gem_object_unbind(obj);
if (ret != 0) {
DRM_ERROR("Error unbinding object: %d\n", ret);
return ret;
}
}
return 0;
}