linux/drivers/gpu/drm/i915/i915_gem_evict.c
Akash Goel 3b3f1650b1 drm/i915: Allocate intel_engine_cs structure only for the enabled engines
With the possibility of addition of many more number of rings in future,
the drm_i915_private structure could bloat as an array, of type
intel_engine_cs, is embedded inside it.
	struct intel_engine_cs engine[I915_NUM_ENGINES];
Though this is still fine as generally there is only a single instance of
drm_i915_private structure used, but not all of the possible rings would be
enabled or active on most of the platforms. Some memory can be saved by
allocating intel_engine_cs structure only for the enabled/active engines.
Currently the engine/ring ID is kept static and dev_priv->engine[] is simply
indexed using the enums defined in intel_engine_id.
To save memory and continue using the static engine/ring IDs, 'engine' is
defined as an array of pointers.
	struct intel_engine_cs *engine[I915_NUM_ENGINES];
dev_priv->engine[engine_ID] will be NULL for disabled engine instances.

There is a text size reduction of 928 bytes, from 1028200 to 1027272, for
i915.o file (but for i915.ko file text size remain same as 1193131 bytes).

v2:
- Remove the engine iterator field added in drm_i915_private structure,
  instead pass a local iterator variable to the for_each_engine**
  macros. (Chris)
- Do away with intel_engine_initialized() and instead directly use the
  NULL pointer check on engine pointer. (Chris)

v3:
- Remove for_each_engine_id() macro, as the updated macro for_each_engine()
  can be used in place of it. (Chris)
- Protect the access to Render engine Fault register with a NULL check, as
  engine specific init is done later in Driver load sequence.

v4:
- Use !!dev_priv->engine[VCS] style for the engine check in getparam. (Chris)
- Kill the superfluous init_engine_lists().

v5:
- Cleanup the intel_engines_init() & intel_engines_setup(), with respect to
  allocation of intel_engine_cs structure. (Chris)

v6:
- Rebase.

v7:
- Optimize the for_each_engine_masked() macro. (Chris)
- Change the type of 'iter' local variable to enum intel_engine_id. (Chris)
- Rebase.

v8: Rebase.

v9: Rebase.

v10:
- For index calculation use engine ID instead of pointer based arithmetic in
  intel_engine_sync_index() as engine pointers are not contiguous now (Chris)
- For appropriateness, rename local enum variable 'iter' to 'id'. (Joonas)
- Use for_each_engine macro for cleanup in intel_engines_init() and remove
  check for NULL engine pointer in cleanup() routines. (Joonas)

v11: Rebase.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476378888-7372-1-git-send-email-akash.goel@intel.com
2016-10-14 09:58:43 +01:00

297 lines
8.5 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
gpu_is_idle(struct drm_i915_private *dev_priv)
{
struct intel_engine_cs *engine;
enum intel_engine_id id;
for_each_engine(engine, dev_priv, id) {
if (intel_engine_is_active(engine))
return false;
}
return true;
}
static bool
mark_free(struct i915_vma *vma, unsigned int flags, struct list_head *unwind)
{
if (i915_vma_is_pinned(vma))
return false;
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);
}
/**
* i915_gem_evict_something - Evict vmas to make room for binding a new one
* @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 i915_address_space *vm,
u64 min_size, u64 alignment,
unsigned cache_level,
u64 start, u64 end,
unsigned flags)
{
struct drm_i915_private *dev_priv = to_i915(vm->dev);
struct list_head eviction_list;
struct list_head *phases[] = {
&vm->inactive_list,
&vm->active_list,
NULL,
}, **phase;
struct i915_vma *vma, *next;
int ret;
trace_i915_gem_evict(vm, 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 in flight,
* on the active list, again in retirement order.
*
* The retirement sequence is thus:
* 1. Inactive objects (already retired)
* 2. Active objects (will stall on unbinding)
*
* On each list, the oldest objects lie at the HEAD with the freshest
* object on the TAIL.
*/
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);
if (flags & PIN_NONBLOCK)
phases[1] = NULL;
search_again:
INIT_LIST_HEAD(&eviction_list);
phase = phases;
do {
list_for_each_entry(vma, *phase, vm_link)
if (mark_free(vma, flags, &eviction_list))
goto found;
} while (*++phase);
/* Nothing found, clean up and bail out! */
list_for_each_entry_safe(vma, next, &eviction_list, exec_list) {
ret = drm_mm_scan_remove_block(&vma->node);
BUG_ON(ret);
INIT_LIST_HEAD(&vma->exec_list);
}
/* Can we unpin some objects such as idle hw contents,
* or pending flips? But since only the GGTT has global entries
* such as scanouts, rinbuffers and contexts, we can skip the
* purge when inspecting per-process local address spaces.
*/
if (!i915_is_ggtt(vm) || flags & PIN_NONBLOCK)
return -ENOSPC;
if (gpu_is_idle(dev_priv)) {
/* 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(vm->dev) ? -EAGAIN : -ENOSPC;
}
/* Not everything in the GGTT is tracked via vma (otherwise we
* could evict as required with minimal stalling) so we are forced
* to idle the GPU and explicitly retire outstanding requests in
* the hopes that we can then remove contexts and the like only
* bound by their active reference.
*/
ret = i915_gem_switch_to_kernel_context(dev_priv);
if (ret)
return ret;
ret = i915_gem_wait_for_idle(dev_priv,
I915_WAIT_INTERRUPTIBLE |
I915_WAIT_LOCKED);
if (ret)
return ret;
i915_gem_retire_requests(dev_priv);
goto search_again;
found:
/* drm_mm doesn't allow any other other operations while
* scanning, therefore store to-be-evicted objects on a
* temporary list and take a reference for all before
* calling unbind (which may remove the active reference
* of any of our objects, thus corrupting the list).
*/
list_for_each_entry_safe(vma, next, &eviction_list, exec_list) {
if (drm_mm_scan_remove_block(&vma->node))
__i915_vma_pin(vma);
else
list_del_init(&vma->exec_list);
}
/* Unbinding will emit any required flushes */
while (!list_empty(&eviction_list)) {
vma = list_first_entry(&eviction_list,
struct i915_vma,
exec_list);
list_del_init(&vma->exec_list);
__i915_vma_unpin(vma);
if (ret == 0)
ret = i915_vma_unbind(vma);
}
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 (i915_vma_is_pinned(vma)) {
if (!vma->exec_entry || i915_vma_pin_count(vma) > 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) {
struct drm_i915_private *dev_priv = to_i915(vm->dev);
if (i915_is_ggtt(vm)) {
ret = i915_gem_switch_to_kernel_context(dev_priv);
if (ret)
return ret;
}
ret = i915_gem_wait_for_idle(dev_priv,
I915_WAIT_INTERRUPTIBLE |
I915_WAIT_LOCKED);
if (ret)
return ret;
i915_gem_retire_requests(dev_priv);
WARN_ON(!list_empty(&vm->active_list));
}
list_for_each_entry_safe(vma, next, &vm->inactive_list, vm_link)
if (!i915_vma_is_pinned(vma))
WARN_ON(i915_vma_unbind(vma));
return 0;
}