linux-stable/drivers/gpu/drm/i915/i915_gem_evict.c
Chris Wilson 506a8e87d8 drm/i915: Add soft-pinning API for execbuffer
Userspace can pass in an offset that it presumes the object is located
at. The kernel will then do its utmost to fit the object into that
location. The assumption is that userspace is handling its own object
locations (for example along with full-ppgtt) and that the kernel will
rarely have to make space for the user's requests.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

v2: Fixed incorrect eviction found by Michal Winiarski - fix suggested by Chris
Wilson.  Fixed incorrect error paths causing crash found by Michal Winiarski.
(Not published externally)

v3: Rebased because of trivial conflict in object_bind_to_vm.  Fixed eviction
to allow eviction of soft-pinned objects when another soft-pinned object used
by a subsequent execbuffer overlaps reported by Michal Winiarski.
(Not published externally)

v4: Moved soft-pinned objects to the front of ordered_vmas so that they are
pinned first after an address conflict happens to avoid repeated conflicts in
rare cases (Suggested by Chris Wilson).  Expanded comment on
drm_i915_gem_exec_object2.offset to cover this new API.

v5: Added I915_PARAM_HAS_EXEC_SOFTPIN parameter for detecting this capability
(Kristian). Added check for multiple pinnings on eviction (Akash). Made sure
buffers are not considered misplaced without the user specifying
EXEC_OBJECT_SUPPORTS_48B_ADDRESS.  User must assume responsibility for any
addressing workarounds.  Updated object2.offset field comment again to clarify
NO_RELOC case (Chris).  checkpatch cleanup.

v6: Trivial rebase on latest drm-intel-nightly

v7: Catch attempts to pin above the max virtual address size and return
EINVAL (Tvrtko). Decouple EXEC_OBJECT_SUPPORTS_48B_ADDRESS and
EXEC_OBJECT_PINNED flags, user must pass both flags in any attempt to pin
something at an offset above 4GB (Chris, Daniel Vetter).

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Akash Goel <akash.goel@intel.com>
Cc: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Cc: Michal Winiarski <michal.winiarski@intel.com>
Cc: Zou Nanhai <nanhai.zou@intel.com>
Cc: Kristian Høgsberg <hoegsberg@gmail.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Acked-by: PDT
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449575707-20933-1-git-send-email-thomas.daniel@intel.com
2015-12-09 10:20:17 +00:00

278 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 <drm/drmP.h>
#include <drm/i915_drm.h>
#include "i915_drv.h"
#include "intel_drv.h"
#include "i915_trace.h"
static bool
mark_free(struct i915_vma *vma, struct list_head *unwind)
{
if (vma->pin_count)
return false;
if (WARN_ON(!list_empty(&vma->exec_list)))
return false;
list_add(&vma->exec_list, unwind);
return drm_mm_scan_add_block(&vma->node);
}
/**
* i915_gem_evict_something - Evict vmas to make room for binding a new one
* @dev: drm_device
* @vm: address space to evict from
* @min_size: size of the desired free space
* @alignment: alignment constraint of the desired free space
* @cache_level: cache_level for the desired space
* @start: start (inclusive) of the range from which to evict objects
* @end: end (exclusive) of the range from which to evict objects
* @flags: additional flags to control the eviction algorithm
*
* This function will try to evict vmas until a free space satisfying the
* requirements is found. Callers must check first whether any such hole exists
* already before calling this function.
*
* This function is used by the object/vma binding code.
*
* Since this function is only used to free up virtual address space it only
* ignores pinned vmas, and not object where the backing storage itself is
* pinned. Hence obj->pages_pin_count does not protect against eviction.
*
* To clarify: This is for freeing up virtual address space, not for freeing
* memory in e.g. the shrinker.
*/
int
i915_gem_evict_something(struct drm_device *dev, struct i915_address_space *vm,
int min_size, unsigned alignment, unsigned cache_level,
unsigned long start, unsigned long end,
unsigned flags)
{
struct list_head eviction_list, unwind_list;
struct i915_vma *vma;
int ret = 0;
int pass = 0;
trace_i915_gem_evict(dev, min_size, alignment, flags);
/*
* 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);
if (start != 0 || end != vm->total) {
drm_mm_init_scan_with_range(&vm->mm, min_size,
alignment, cache_level,
start, end);
} else
drm_mm_init_scan(&vm->mm, min_size, alignment, cache_level);
search_again:
/* First see if there is a large enough contiguous idle region... */
list_for_each_entry(vma, &vm->inactive_list, mm_list) {
if (mark_free(vma, &unwind_list))
goto found;
}
if (flags & PIN_NONBLOCK)
goto none;
/* Now merge in the soon-to-be-expired objects... */
list_for_each_entry(vma, &vm->active_list, mm_list) {
if (mark_free(vma, &unwind_list))
goto found;
}
none:
/* Nothing found, clean up and bail out! */
while (!list_empty(&unwind_list)) {
vma = list_first_entry(&unwind_list,
struct i915_vma,
exec_list);
ret = drm_mm_scan_remove_block(&vma->node);
BUG_ON(ret);
list_del_init(&vma->exec_list);
}
/* Can we unpin some objects such as idle hw contents,
* or pending flips?
*/
if (flags & PIN_NONBLOCK)
return -ENOSPC;
/* Only idle the GPU and repeat the search once */
if (pass++ == 0) {
ret = i915_gpu_idle(dev);
if (ret)
return ret;
i915_gem_retire_requests(dev);
goto search_again;
}
/* If we still have pending pageflip completions, drop
* back to userspace to give our workqueues time to
* acquire our locks and unpin the old scanouts.
*/
return intel_has_pending_fb_unpin(dev) ? -EAGAIN : -ENOSPC;
found:
/* drm_mm doesn't allow any other other operations while
* scanning, therefore store to be evicted objects on a
* temporary list. */
INIT_LIST_HEAD(&eviction_list);
while (!list_empty(&unwind_list)) {
vma = list_first_entry(&unwind_list,
struct i915_vma,
exec_list);
if (drm_mm_scan_remove_block(&vma->node)) {
list_move(&vma->exec_list, &eviction_list);
drm_gem_object_reference(&vma->obj->base);
continue;
}
list_del_init(&vma->exec_list);
}
/* Unbinding will emit any required flushes */
while (!list_empty(&eviction_list)) {
struct drm_gem_object *obj;
vma = list_first_entry(&eviction_list,
struct i915_vma,
exec_list);
obj = &vma->obj->base;
list_del_init(&vma->exec_list);
if (ret == 0)
ret = i915_vma_unbind(vma);
drm_gem_object_unreference(obj);
}
return ret;
}
int
i915_gem_evict_for_vma(struct i915_vma *target)
{
struct drm_mm_node *node, *next;
list_for_each_entry_safe(node, next,
&target->vm->mm.head_node.node_list,
node_list) {
struct i915_vma *vma;
int ret;
if (node->start + node->size <= target->node.start)
continue;
if (node->start >= target->node.start + target->node.size)
break;
vma = container_of(node, typeof(*vma), node);
if (vma->pin_count) {
if (!vma->exec_entry || (vma->pin_count > 1))
/* Object is pinned for some other use */
return -EBUSY;
/* We need to evict a buffer in the same batch */
if (vma->exec_entry->flags & EXEC_OBJECT_PINNED)
/* Overlapping fixed objects in the same batch */
return -EINVAL;
return -ENOSPC;
}
ret = i915_vma_unbind(vma);
if (ret)
return ret;
}
return 0;
}
/**
* i915_gem_evict_vm - Evict all idle vmas from a vm
* @vm: Address space to cleanse
* @do_idle: Boolean directing whether to idle first.
*
* This function evicts all idles vmas from a vm. If all unpinned vmas should be
* evicted the @do_idle needs to be set to true.
*
* This is used by the execbuf code as a last-ditch effort to defragment the
* address space.
*
* To clarify: This is for freeing up virtual address space, not for freeing
* memory in e.g. the shrinker.
*/
int i915_gem_evict_vm(struct i915_address_space *vm, bool do_idle)
{
struct i915_vma *vma, *next;
int ret;
WARN_ON(!mutex_is_locked(&vm->dev->struct_mutex));
trace_i915_gem_evict_vm(vm);
if (do_idle) {
ret = i915_gpu_idle(vm->dev);
if (ret)
return ret;
i915_gem_retire_requests(vm->dev);
WARN_ON(!list_empty(&vm->active_list));
}
list_for_each_entry_safe(vma, next, &vm->inactive_list, mm_list)
if (vma->pin_count == 0)
WARN_ON(i915_vma_unbind(vma));
return 0;
}