linux-stable/drivers/gpu/drm/i915/selftests/i915_gem_evict.c
Matthew Auld 3f882f2d4f drm/i915: improve the catch-all evict to handle lock contention
The catch-all evict can fail due to object lock contention, since it
only goes as far as trylocking the object, due to us already holding the
vm->mutex. Doing a full object lock here can deadlock, since the
vm->mutex is always our inner lock. Add another execbuf pass which drops
the vm->mutex and then tries to grab the object will the full lock,
before then retrying the eviction. This should be good enough for now to
fix the immediate regression with userspace seeing -ENOSPC from execbuf
due to contended object locks during GTT eviction.

v2 (Mani)
  - Also revamp the docs for the different passes.

Testcase: igt@gem_ppgtt@shrink-vs-evict-*
Fixes: 7e00897be8 ("drm/i915: Add object locking to i915_gem_evict_for_node and i915_gem_evict_something, v2.")
References: https://gitlab.freedesktop.org/drm/intel/-/issues/7627
References: https://gitlab.freedesktop.org/drm/intel/-/issues/7570
References: https://bugzilla.mozilla.org/show_bug.cgi?id=1779558
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Mani Milani <mani@chromium.org>
Cc: <stable@vger.kernel.org> # v5.18+
Reviewed-by: Mani Milani <mani@chromium.org>
Tested-by: Mani Milani <mani@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221216113456.414183-1-matthew.auld@intel.com
(cherry picked from commit 801fa7a81f)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
2022-12-30 03:04:39 -05:00

569 lines
14 KiB
C

/*
* Copyright © 2016 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.
*
*/
#include "gem/i915_gem_internal.h"
#include "gem/i915_gem_pm.h"
#include "gem/selftests/igt_gem_utils.h"
#include "gem/selftests/mock_context.h"
#include "gt/intel_gt.h"
#include "i915_selftest.h"
#include "igt_flush_test.h"
#include "lib_sw_fence.h"
#include "mock_drm.h"
#include "mock_gem_device.h"
static void quirk_add(struct drm_i915_gem_object *obj,
struct list_head *objects)
{
/* quirk is only for live tiled objects, use it to declare ownership */
GEM_BUG_ON(i915_gem_object_has_tiling_quirk(obj));
i915_gem_object_set_tiling_quirk(obj);
list_add(&obj->st_link, objects);
}
static int populate_ggtt(struct i915_ggtt *ggtt, struct list_head *objects)
{
struct drm_i915_gem_object *obj;
unsigned long count;
count = 0;
do {
struct i915_vma *vma;
obj = i915_gem_object_create_internal(ggtt->vm.i915,
I915_GTT_PAGE_SIZE);
if (IS_ERR(obj))
return PTR_ERR(obj);
vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
if (IS_ERR(vma)) {
i915_gem_object_put(obj);
if (vma == ERR_PTR(-ENOSPC))
break;
return PTR_ERR(vma);
}
quirk_add(obj, objects);
count++;
} while (1);
pr_debug("Filled GGTT with %lu pages [%llu total]\n",
count, ggtt->vm.total / PAGE_SIZE);
if (list_empty(&ggtt->vm.bound_list)) {
pr_err("No objects on the GGTT inactive list!\n");
return -EINVAL;
}
return 0;
}
static void unpin_ggtt(struct i915_ggtt *ggtt)
{
struct i915_vma *vma;
list_for_each_entry(vma, &ggtt->vm.bound_list, vm_link)
if (i915_gem_object_has_tiling_quirk(vma->obj))
i915_vma_unpin(vma);
}
static void cleanup_objects(struct i915_ggtt *ggtt, struct list_head *list)
{
struct drm_i915_gem_object *obj, *on;
list_for_each_entry_safe(obj, on, list, st_link) {
GEM_BUG_ON(!i915_gem_object_has_tiling_quirk(obj));
i915_gem_object_set_tiling_quirk(obj);
i915_gem_object_put(obj);
}
i915_gem_drain_freed_objects(ggtt->vm.i915);
}
static int igt_evict_something(void *arg)
{
struct intel_gt *gt = arg;
struct i915_ggtt *ggtt = gt->ggtt;
LIST_HEAD(objects);
int err;
/* Fill the GGTT with pinned objects and try to evict one. */
err = populate_ggtt(ggtt, &objects);
if (err)
goto cleanup;
/* Everything is pinned, nothing should happen */
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_evict_something(&ggtt->vm, NULL,
I915_GTT_PAGE_SIZE, 0, 0,
0, U64_MAX,
0);
mutex_unlock(&ggtt->vm.mutex);
if (err != -ENOSPC) {
pr_err("i915_gem_evict_something failed on a full GGTT with err=%d\n",
err);
goto cleanup;
}
unpin_ggtt(ggtt);
/* Everything is unpinned, we should be able to evict something */
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_evict_something(&ggtt->vm, NULL,
I915_GTT_PAGE_SIZE, 0, 0,
0, U64_MAX,
0);
mutex_unlock(&ggtt->vm.mutex);
if (err) {
pr_err("i915_gem_evict_something failed on a full GGTT with err=%d\n",
err);
goto cleanup;
}
cleanup:
cleanup_objects(ggtt, &objects);
return err;
}
static int igt_overcommit(void *arg)
{
struct intel_gt *gt = arg;
struct i915_ggtt *ggtt = gt->ggtt;
struct drm_i915_gem_object *obj;
struct i915_vma *vma;
LIST_HEAD(objects);
int err;
/* Fill the GGTT with pinned objects and then try to pin one more.
* We expect it to fail.
*/
err = populate_ggtt(ggtt, &objects);
if (err)
goto cleanup;
obj = i915_gem_object_create_internal(gt->i915, I915_GTT_PAGE_SIZE);
if (IS_ERR(obj)) {
err = PTR_ERR(obj);
goto cleanup;
}
quirk_add(obj, &objects);
vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
if (vma != ERR_PTR(-ENOSPC)) {
pr_err("Failed to evict+insert, i915_gem_object_ggtt_pin returned err=%d\n", (int)PTR_ERR_OR_ZERO(vma));
err = -EINVAL;
goto cleanup;
}
cleanup:
cleanup_objects(ggtt, &objects);
return err;
}
static int igt_evict_for_vma(void *arg)
{
struct intel_gt *gt = arg;
struct i915_ggtt *ggtt = gt->ggtt;
struct drm_mm_node target = {
.start = 0,
.size = 4096,
};
LIST_HEAD(objects);
int err;
/* Fill the GGTT with pinned objects and try to evict a range. */
err = populate_ggtt(ggtt, &objects);
if (err)
goto cleanup;
/* Everything is pinned, nothing should happen */
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_evict_for_node(&ggtt->vm, NULL, &target, 0);
mutex_unlock(&ggtt->vm.mutex);
if (err != -ENOSPC) {
pr_err("i915_gem_evict_for_node on a full GGTT returned err=%d\n",
err);
goto cleanup;
}
unpin_ggtt(ggtt);
/* Everything is unpinned, we should be able to evict the node */
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_evict_for_node(&ggtt->vm, NULL, &target, 0);
mutex_unlock(&ggtt->vm.mutex);
if (err) {
pr_err("i915_gem_evict_for_node returned err=%d\n",
err);
goto cleanup;
}
cleanup:
cleanup_objects(ggtt, &objects);
return err;
}
static void mock_color_adjust(const struct drm_mm_node *node,
unsigned long color,
u64 *start,
u64 *end)
{
}
static int igt_evict_for_cache_color(void *arg)
{
struct intel_gt *gt = arg;
struct i915_ggtt *ggtt = gt->ggtt;
const unsigned long flags = PIN_OFFSET_FIXED;
struct drm_mm_node target = {
.start = I915_GTT_PAGE_SIZE * 2,
.size = I915_GTT_PAGE_SIZE,
.color = I915_CACHE_LLC,
};
struct drm_i915_gem_object *obj;
struct i915_vma *vma;
LIST_HEAD(objects);
int err;
/*
* Currently the use of color_adjust for the GGTT is limited to cache
* coloring and guard pages, and so the presence of mm.color_adjust for
* the GGTT is assumed to be i915_ggtt_color_adjust, hence using a mock
* color adjust will work just fine for our purposes.
*/
ggtt->vm.mm.color_adjust = mock_color_adjust;
GEM_BUG_ON(!i915_vm_has_cache_coloring(&ggtt->vm));
obj = i915_gem_object_create_internal(gt->i915, I915_GTT_PAGE_SIZE);
if (IS_ERR(obj)) {
err = PTR_ERR(obj);
goto cleanup;
}
i915_gem_object_set_cache_coherency(obj, I915_CACHE_LLC);
quirk_add(obj, &objects);
vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
I915_GTT_PAGE_SIZE | flags);
if (IS_ERR(vma)) {
pr_err("[0]i915_gem_object_ggtt_pin failed\n");
err = PTR_ERR(vma);
goto cleanup;
}
obj = i915_gem_object_create_internal(gt->i915, I915_GTT_PAGE_SIZE);
if (IS_ERR(obj)) {
err = PTR_ERR(obj);
goto cleanup;
}
i915_gem_object_set_cache_coherency(obj, I915_CACHE_LLC);
quirk_add(obj, &objects);
/* Neighbouring; same colour - should fit */
vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0,
(I915_GTT_PAGE_SIZE * 2) | flags);
if (IS_ERR(vma)) {
pr_err("[1]i915_gem_object_ggtt_pin failed\n");
err = PTR_ERR(vma);
goto cleanup;
}
i915_vma_unpin(vma);
/* Remove just the second vma */
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_evict_for_node(&ggtt->vm, NULL, &target, 0);
mutex_unlock(&ggtt->vm.mutex);
if (err) {
pr_err("[0]i915_gem_evict_for_node returned err=%d\n", err);
goto cleanup;
}
/* Attempt to remove the first *pinned* vma, by removing the (empty)
* neighbour -- this should fail.
*/
target.color = I915_CACHE_L3_LLC;
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_evict_for_node(&ggtt->vm, NULL, &target, 0);
mutex_unlock(&ggtt->vm.mutex);
if (!err) {
pr_err("[1]i915_gem_evict_for_node returned err=%d\n", err);
err = -EINVAL;
goto cleanup;
}
err = 0;
cleanup:
unpin_ggtt(ggtt);
cleanup_objects(ggtt, &objects);
ggtt->vm.mm.color_adjust = NULL;
return err;
}
static int igt_evict_vm(void *arg)
{
struct intel_gt *gt = arg;
struct i915_ggtt *ggtt = gt->ggtt;
struct i915_gem_ww_ctx ww;
LIST_HEAD(objects);
int err;
/* Fill the GGTT with pinned objects and try to evict everything. */
err = populate_ggtt(ggtt, &objects);
if (err)
goto cleanup;
/* Everything is pinned, nothing should happen */
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_evict_vm(&ggtt->vm, NULL, NULL);
mutex_unlock(&ggtt->vm.mutex);
if (err) {
pr_err("i915_gem_evict_vm on a full GGTT returned err=%d]\n",
err);
goto cleanup;
}
unpin_ggtt(ggtt);
for_i915_gem_ww(&ww, err, false) {
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_evict_vm(&ggtt->vm, &ww, NULL);
mutex_unlock(&ggtt->vm.mutex);
}
if (err) {
pr_err("i915_gem_evict_vm on a full GGTT returned err=%d]\n",
err);
goto cleanup;
}
cleanup:
cleanup_objects(ggtt, &objects);
return err;
}
static int igt_evict_contexts(void *arg)
{
const u64 PRETEND_GGTT_SIZE = 16ull << 20;
struct intel_gt *gt = arg;
struct i915_ggtt *ggtt = gt->ggtt;
struct drm_i915_private *i915 = gt->i915;
struct intel_engine_cs *engine;
enum intel_engine_id id;
struct reserved {
struct drm_mm_node node;
struct reserved *next;
} *reserved = NULL;
intel_wakeref_t wakeref;
struct drm_mm_node hole;
unsigned long count;
int err;
/*
* The purpose of this test is to verify that we will trigger an
* eviction in the GGTT when constructing a request that requires
* additional space in the GGTT for pinning the context. This space
* is not directly tied to the request so reclaiming it requires
* extra work.
*
* As such this test is only meaningful for full-ppgtt environments
* where the GTT space of the request is separate from the GGTT
* allocation required to build the request.
*/
if (!HAS_FULL_PPGTT(i915))
return 0;
wakeref = intel_runtime_pm_get(&i915->runtime_pm);
/* Reserve a block so that we know we have enough to fit a few rq */
memset(&hole, 0, sizeof(hole));
mutex_lock(&ggtt->vm.mutex);
err = i915_gem_gtt_insert(&ggtt->vm, NULL, &hole,
PRETEND_GGTT_SIZE, 0, I915_COLOR_UNEVICTABLE,
0, ggtt->vm.total,
PIN_NOEVICT);
if (err)
goto out_locked;
/* Make the GGTT appear small by filling it with unevictable nodes */
count = 0;
do {
struct reserved *r;
mutex_unlock(&ggtt->vm.mutex);
r = kcalloc(1, sizeof(*r), GFP_KERNEL);
mutex_lock(&ggtt->vm.mutex);
if (!r) {
err = -ENOMEM;
goto out_locked;
}
if (i915_gem_gtt_insert(&ggtt->vm, NULL, &r->node,
1ul << 20, 0, I915_COLOR_UNEVICTABLE,
0, ggtt->vm.total,
PIN_NOEVICT)) {
kfree(r);
break;
}
r->next = reserved;
reserved = r;
count++;
} while (1);
drm_mm_remove_node(&hole);
mutex_unlock(&ggtt->vm.mutex);
pr_info("Filled GGTT with %lu 1MiB nodes\n", count);
/* Overfill the GGTT with context objects and so try to evict one. */
for_each_engine(engine, gt, id) {
struct i915_sw_fence fence;
struct i915_request *last = NULL;
count = 0;
onstack_fence_init(&fence);
do {
struct intel_context *ce;
struct i915_request *rq;
ce = intel_context_create(engine);
if (IS_ERR(ce))
break;
/* We will need some GGTT space for the rq's context */
igt_evict_ctl.fail_if_busy = true;
rq = intel_context_create_request(ce);
igt_evict_ctl.fail_if_busy = false;
intel_context_put(ce);
if (IS_ERR(rq)) {
/* When full, fail_if_busy will trigger EBUSY */
if (PTR_ERR(rq) != -EBUSY) {
pr_err("Unexpected error from request alloc (on %s): %d\n",
engine->name,
(int)PTR_ERR(rq));
err = PTR_ERR(rq);
}
break;
}
/* Keep every request/ctx pinned until we are full */
err = i915_sw_fence_await_sw_fence_gfp(&rq->submit,
&fence,
GFP_KERNEL);
if (err < 0)
break;
i915_request_add(rq);
count++;
if (last)
i915_request_put(last);
last = i915_request_get(rq);
err = 0;
} while(1);
onstack_fence_fini(&fence);
pr_info("Submitted %lu contexts/requests on %s\n",
count, engine->name);
if (err)
break;
if (last) {
if (i915_request_wait(last, 0, HZ) < 0) {
err = -EIO;
i915_request_put(last);
pr_err("Failed waiting for last request (on %s)",
engine->name);
break;
}
i915_request_put(last);
}
err = intel_gt_wait_for_idle(engine->gt, HZ * 3);
if (err) {
pr_err("Failed to idle GT (on %s)", engine->name);
break;
}
}
mutex_lock(&ggtt->vm.mutex);
out_locked:
if (igt_flush_test(i915))
err = -EIO;
while (reserved) {
struct reserved *next = reserved->next;
drm_mm_remove_node(&reserved->node);
kfree(reserved);
reserved = next;
}
if (drm_mm_node_allocated(&hole))
drm_mm_remove_node(&hole);
mutex_unlock(&ggtt->vm.mutex);
intel_runtime_pm_put(&i915->runtime_pm, wakeref);
return err;
}
int i915_gem_evict_mock_selftests(void)
{
static const struct i915_subtest tests[] = {
SUBTEST(igt_evict_something),
SUBTEST(igt_evict_for_vma),
SUBTEST(igt_evict_for_cache_color),
SUBTEST(igt_evict_vm),
SUBTEST(igt_overcommit),
};
struct drm_i915_private *i915;
intel_wakeref_t wakeref;
int err = 0;
i915 = mock_gem_device();
if (!i915)
return -ENOMEM;
with_intel_runtime_pm(&i915->runtime_pm, wakeref)
err = i915_subtests(tests, to_gt(i915));
mock_destroy_device(i915);
return err;
}
int i915_gem_evict_live_selftests(struct drm_i915_private *i915)
{
static const struct i915_subtest tests[] = {
SUBTEST(igt_evict_contexts),
};
if (intel_gt_is_wedged(to_gt(i915)))
return 0;
return intel_gt_live_subtests(tests, to_gt(i915));
}