From 950505cabe517ad40759cae6f88f33f0bdfbb7c8 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= Date: Mon, 10 Jan 2022 18:22:18 +0100 Subject: [PATCH] drm/i915: Asynchronous migration selftest MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a selftest to exercise asynchronous migration and -unbining. Extend the gem_migrate selftest to perform the migrations while depending on a spinner and a bound vma set up on the migrated buffer object. Signed-off-by: Thomas Hellström Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20220110172219.107131-6-thomas.hellstrom@linux.intel.com --- drivers/gpu/drm/i915/gem/i915_gem_object.c | 12 ++ drivers/gpu/drm/i915/gem/i915_gem_object.h | 3 + .../drm/i915/gem/selftests/i915_gem_migrate.c | 192 ++++++++++++++++-- 3 files changed, 192 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c index d87b508b59b1..1a9e1f940a7d 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c @@ -756,6 +756,18 @@ i915_gem_object_get_moving_fence(struct drm_i915_gem_object *obj) return dma_fence_get(i915_gem_to_ttm(obj)->moving); } +void i915_gem_object_set_moving_fence(struct drm_i915_gem_object *obj, + struct dma_fence *fence) +{ + struct dma_fence **moving = &i915_gem_to_ttm(obj)->moving; + + if (*moving == fence) + return; + + dma_fence_put(*moving); + *moving = dma_fence_get(fence); +} + /** * i915_gem_object_wait_moving_fence - Wait for the object's moving fence if any * @obj: The object whose moving fence to wait for. diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h index bc448f895ae8..02c37fe4a535 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h @@ -523,6 +523,9 @@ i915_gem_object_finish_access(struct drm_i915_gem_object *obj) struct dma_fence * i915_gem_object_get_moving_fence(struct drm_i915_gem_object *obj); +void i915_gem_object_set_moving_fence(struct drm_i915_gem_object *obj, + struct dma_fence *fence); + int i915_gem_object_wait_moving_fence(struct drm_i915_gem_object *obj, bool intr); diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c index ecb691c81d1e..d534141b2cf7 100644 --- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c +++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c @@ -4,8 +4,13 @@ */ #include "gt/intel_migrate.h" +#include "gt/intel_gpu_commands.h" #include "gem/i915_gem_ttm_move.h" +#include "i915_deps.h" + +#include "selftests/igt_spinner.h" + static int igt_fill_check_buffer(struct drm_i915_gem_object *obj, bool fill) { @@ -101,7 +106,8 @@ static int igt_same_create_migrate(void *arg) } static int lmem_pages_migrate_one(struct i915_gem_ww_ctx *ww, - struct drm_i915_gem_object *obj) + struct drm_i915_gem_object *obj, + struct i915_vma *vma) { int err; @@ -109,6 +115,24 @@ static int lmem_pages_migrate_one(struct i915_gem_ww_ctx *ww, if (err) return err; + if (vma) { + err = i915_vma_pin_ww(vma, ww, obj->base.size, 0, + 0UL | PIN_OFFSET_FIXED | + PIN_USER); + if (err) { + if (err != -EINTR && err != ERESTARTSYS && + err != -EDEADLK) + pr_err("Failed to pin vma.\n"); + return err; + } + + i915_vma_unpin(vma); + } + + /* + * Migration will implicitly unbind (asynchronously) any bound + * vmas. + */ if (i915_gem_object_is_lmem(obj)) { err = i915_gem_object_migrate(obj, ww, INTEL_REGION_SMEM); if (err) { @@ -149,11 +173,15 @@ static int lmem_pages_migrate_one(struct i915_gem_ww_ctx *ww, return err; } -static int igt_lmem_pages_migrate(void *arg) +static int __igt_lmem_pages_migrate(struct intel_gt *gt, + struct i915_address_space *vm, + struct i915_deps *deps, + struct igt_spinner *spin, + struct dma_fence *spin_fence) { - struct intel_gt *gt = arg; struct drm_i915_private *i915 = gt->i915; struct drm_i915_gem_object *obj; + struct i915_vma *vma = NULL; struct i915_gem_ww_ctx ww; struct i915_request *rq; int err; @@ -165,6 +193,14 @@ static int igt_lmem_pages_migrate(void *arg) if (IS_ERR(obj)) return PTR_ERR(obj); + if (vm) { + vma = i915_vma_instance(obj, vm, NULL); + if (IS_ERR(vma)) { + err = PTR_ERR(vma); + goto out_put; + } + } + /* Initial GPU fill, sync, CPU initialization. */ for_i915_gem_ww(&ww, err, true) { err = i915_gem_object_lock(obj, &ww); @@ -175,25 +211,23 @@ static int igt_lmem_pages_migrate(void *arg) if (err) continue; - err = intel_migrate_clear(>->migrate, &ww, NULL, + err = intel_migrate_clear(>->migrate, &ww, deps, obj->mm.pages->sgl, obj->cache_level, i915_gem_object_is_lmem(obj), 0xdeadbeaf, &rq); if (rq) { dma_resv_add_excl_fence(obj->base.resv, &rq->fence); + i915_gem_object_set_moving_fence(obj, &rq->fence); i915_request_put(rq); } if (err) continue; - err = i915_gem_object_wait(obj, I915_WAIT_INTERRUPTIBLE, - 5 * HZ); - if (err) - continue; - - err = igt_fill_check_buffer(obj, true); - if (err) - continue; + if (!vma) { + err = igt_fill_check_buffer(obj, true); + if (err) + continue; + } } if (err) goto out_put; @@ -204,7 +238,7 @@ static int igt_lmem_pages_migrate(void *arg) */ for (i = 1; i <= 5; ++i) { for_i915_gem_ww(&ww, err, true) - err = lmem_pages_migrate_one(&ww, obj); + err = lmem_pages_migrate_one(&ww, obj, vma); if (err) goto out_put; } @@ -213,12 +247,27 @@ static int igt_lmem_pages_migrate(void *arg) if (err) goto out_put; + if (spin) { + if (dma_fence_is_signaled(spin_fence)) { + pr_err("Spinner was terminated by hangcheck.\n"); + err = -EBUSY; + goto out_unlock; + } + igt_spinner_end(spin); + } + /* Finally sync migration and check content. */ err = i915_gem_object_wait_migration(obj, true); if (err) goto out_unlock; - err = igt_fill_check_buffer(obj, false); + if (vma) { + err = i915_vma_wait_for_bind(vma); + if (err) + goto out_unlock; + } else { + err = igt_fill_check_buffer(obj, false); + } out_unlock: i915_gem_object_unlock(obj); @@ -231,6 +280,7 @@ static int igt_lmem_pages_migrate(void *arg) static int igt_lmem_pages_failsafe_migrate(void *arg) { int fail_gpu, fail_alloc, ret; + struct intel_gt *gt = arg; for (fail_gpu = 0; fail_gpu < 2; ++fail_gpu) { for (fail_alloc = 0; fail_alloc < 2; ++fail_alloc) { @@ -238,7 +288,118 @@ static int igt_lmem_pages_failsafe_migrate(void *arg) fail_gpu, fail_alloc); i915_ttm_migrate_set_failure_modes(fail_gpu, fail_alloc); - ret = igt_lmem_pages_migrate(arg); + ret = __igt_lmem_pages_migrate(gt, NULL, NULL, NULL, NULL); + if (ret) + goto out_err; + } + } + +out_err: + i915_ttm_migrate_set_failure_modes(false, false); + return ret; +} + +/* + * This subtest tests that unbinding at migration is indeed performed + * async. We launch a spinner and a number of migrations depending on + * that spinner to have terminated. Before each migration we bind a + * vma, which should then be async unbound by the migration operation. + * If we are able to schedule migrations without blocking while the + * spinner is still running, those unbinds are indeed async and non- + * blocking. + * + * Note that each async bind operation is awaiting the previous migration + * due to the moving fence resulting from the migration. + */ +static int igt_async_migrate(struct intel_gt *gt) +{ + struct intel_engine_cs *engine; + enum intel_engine_id id; + struct i915_ppgtt *ppgtt; + struct igt_spinner spin; + int err; + + ppgtt = i915_ppgtt_create(gt, 0); + if (IS_ERR(ppgtt)) + return PTR_ERR(ppgtt); + + if (igt_spinner_init(&spin, gt)) { + err = -ENOMEM; + goto out_spin; + } + + for_each_engine(engine, gt, id) { + struct ttm_operation_ctx ctx = { + .interruptible = true + }; + struct dma_fence *spin_fence; + struct intel_context *ce; + struct i915_request *rq; + struct i915_deps deps; + + ce = intel_context_create(engine); + if (IS_ERR(ce)) { + err = PTR_ERR(ce); + goto out_ce; + } + + /* + * Use MI_NOOP, making the spinner non-preemptible. If there + * is a code path where we fail async operation due to the + * running spinner, we will block and fail to end the + * spinner resulting in a deadlock. But with a non- + * preemptible spinner, hangcheck will terminate the spinner + * for us, and we will later detect that and fail the test. + */ + rq = igt_spinner_create_request(&spin, ce, MI_NOOP); + intel_context_put(ce); + if (IS_ERR(rq)) { + err = PTR_ERR(rq); + goto out_ce; + } + + i915_deps_init(&deps, GFP_KERNEL); + err = i915_deps_add_dependency(&deps, &rq->fence, &ctx); + spin_fence = dma_fence_get(&rq->fence); + i915_request_add(rq); + if (err) + goto out_ce; + + err = __igt_lmem_pages_migrate(gt, &ppgtt->vm, &deps, &spin, + spin_fence); + i915_deps_fini(&deps); + dma_fence_put(spin_fence); + if (err) + goto out_ce; + } + +out_ce: + igt_spinner_fini(&spin); +out_spin: + i915_vm_put(&ppgtt->vm); + + return err; +} + +/* + * Setting ASYNC_FAIL_ALLOC to 2 will simulate memory allocation failure while + * arming the migration error check and block async migration. This + * will cause us to deadlock and hangcheck will terminate the spinner + * causing the test to fail. + */ +#define ASYNC_FAIL_ALLOC 1 +static int igt_lmem_async_migrate(void *arg) +{ + int fail_gpu, fail_alloc, ret; + struct intel_gt *gt = arg; + + for (fail_gpu = 0; fail_gpu < 2; ++fail_gpu) { + for (fail_alloc = 0; fail_alloc < ASYNC_FAIL_ALLOC; ++fail_alloc) { + pr_info("Simulated failure modes: gpu: %d, alloc: %d\n", + fail_gpu, fail_alloc); + i915_ttm_migrate_set_failure_modes(fail_gpu, + fail_alloc); + ret = igt_async_migrate(gt); if (ret) goto out_err; } @@ -256,6 +417,7 @@ int i915_gem_migrate_live_selftests(struct drm_i915_private *i915) SUBTEST(igt_lmem_create_migrate), SUBTEST(igt_same_create_migrate), SUBTEST(igt_lmem_pages_failsafe_migrate), + SUBTEST(igt_lmem_async_migrate), }; if (!HAS_LMEM(i915))