Testing the stealing of guc ids is hard from user space as we have 64k guc_ids. Add a selftest, which artificially reduces the number of guc ids, and forces a steal.
The test creates a spinner which is used to block all subsequent submissions until it completes. Next, a loop creates a context and a NOP request each iteration until the guc_ids are exhausted (request creation returns -EAGAIN). The spinner is ended, unblocking all requests created in the loop. At this point all guc_ids are exhausted but are available to steal. Try to create another request which should successfully steal a guc_id. Wait on last request to complete, idle GPU, verify a guc_id was stolen via a counter, and exit the test. Test also artificially reduces the number of guc_ids so the test runs in a timely manner.
v2: (John Harrison) - s/stole/stolen - Fix some wording in test description - Rework indexing into context array - Add test description to commit message - Fix typo in commit message (Checkpatch) - s/guc/(guc) in NUMBER_MULTI_LRC_GUC_ID v3: (John Harrison) - Set array value to NULL after extracting error - Fix a few typos in comments / error messages - Delete redundant comment in commit message
Signed-off-by: Matthew Brost matthew.brost@intel.com --- drivers/gpu/drm/i915/gt/uc/intel_guc.h | 12 ++ .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 16 +- drivers/gpu/drm/i915/gt/uc/selftest_guc.c | 173 ++++++++++++++++++ 3 files changed, 196 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h index 1cb46098030d..f9240d4baa69 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h @@ -94,6 +94,11 @@ struct intel_guc { * @guc_ids: used to allocate new guc_ids, single-lrc */ struct ida guc_ids; + /** + * @num_guc_ids: Number of guc_ids, selftest feature to be able + * to reduce this number while testing. + */ + int num_guc_ids; /** * @guc_ids_bitmap: used to allocate new guc_ids, multi-lrc */ @@ -202,6 +207,13 @@ struct intel_guc { */ struct delayed_work work; } timestamp; + +#ifdef CONFIG_DRM_I915_SELFTEST + /** + * @number_guc_id_stolen: The number of guc_ids that have been stolen + */ + int number_guc_id_stolen; +#endif };
static inline struct intel_guc *log_to_guc(struct intel_guc_log *log) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c index 96fcf869e3ff..99414b49ca6d 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -145,7 +145,8 @@ guc_create_parallel(struct intel_engine_cs **engines, * use should be low and 1/16 should be sufficient. Minimum of 32 guc_ids for * multi-lrc. */ -#define NUMBER_MULTI_LRC_GUC_ID (GUC_MAX_LRC_DESCRIPTORS / 16) +#define NUMBER_MULTI_LRC_GUC_ID(guc) \ + ((guc)->submission_state.num_guc_ids / 16)
/* * Below is a set of functions which control the GuC scheduling state which @@ -1775,7 +1776,7 @@ int intel_guc_submission_init(struct intel_guc *guc) destroyed_worker_func);
guc->submission_state.guc_ids_bitmap = - bitmap_zalloc(NUMBER_MULTI_LRC_GUC_ID, GFP_KERNEL); + bitmap_zalloc(NUMBER_MULTI_LRC_GUC_ID(guc), GFP_KERNEL); if (!guc->submission_state.guc_ids_bitmap) return -ENOMEM;
@@ -1869,13 +1870,13 @@ static int new_guc_id(struct intel_guc *guc, struct intel_context *ce)
if (intel_context_is_parent(ce)) ret = bitmap_find_free_region(guc->submission_state.guc_ids_bitmap, - NUMBER_MULTI_LRC_GUC_ID, + NUMBER_MULTI_LRC_GUC_ID(guc), order_base_2(ce->parallel.number_children + 1)); else ret = ida_simple_get(&guc->submission_state.guc_ids, - NUMBER_MULTI_LRC_GUC_ID, - GUC_MAX_LRC_DESCRIPTORS, + NUMBER_MULTI_LRC_GUC_ID(guc), + guc->submission_state.num_guc_ids, GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN); if (unlikely(ret < 0)) @@ -1941,6 +1942,10 @@ static int steal_guc_id(struct intel_guc *guc, struct intel_context *ce)
set_context_guc_id_invalid(cn);
+#ifdef CONFIG_DRM_I915_SELFTEST + guc->number_guc_id_stolen++; +#endif + return 0; } else { return -EAGAIN; @@ -3779,6 +3784,7 @@ static bool __guc_submission_selected(struct intel_guc *guc)
void intel_guc_submission_init_early(struct intel_guc *guc) { + guc->submission_state.num_guc_ids = GUC_MAX_LRC_DESCRIPTORS; guc->submission_supported = __guc_submission_supported(guc); guc->submission_selected = __guc_submission_selected(guc); } diff --git a/drivers/gpu/drm/i915/gt/uc/selftest_guc.c b/drivers/gpu/drm/i915/gt/uc/selftest_guc.c index fb0e4a7bd8ca..2ae414446112 100644 --- a/drivers/gpu/drm/i915/gt/uc/selftest_guc.c +++ b/drivers/gpu/drm/i915/gt/uc/selftest_guc.c @@ -3,8 +3,21 @@ * Copyright �� 2021 Intel Corporation */
+#include "selftests/igt_spinner.h" #include "selftests/intel_scheduler_helpers.h"
+static int request_add_spin(struct i915_request *rq, struct igt_spinner *spin) +{ + int err = 0; + + i915_request_get(rq); + i915_request_add(rq); + if (spin && !igt_wait_for_spinner(spin, rq)) + err = -ETIMEDOUT; + + return err; +} + static struct i915_request *nop_user_request(struct intel_context *ce, struct i915_request *from) { @@ -110,10 +123,170 @@ static int intel_guc_scrub_ctbs(void *arg) return ret; }
+/* + * intel_guc_steal_guc_ids - Test to exhaust all guc_ids and then steal one + * + * This test creates a spinner which is used to block all subsequent submissions + * until it completes. Next, a loop creates a context and a NOP request each + * iteration until the guc_ids are exhausted (request creation returns -EAGAIN). + * The spinner is ended, unblocking all requests created in the loop. At this + * point all guc_ids are exhausted but are available to steal. Try to create + * another request which should successfully steal a guc_id. Wait on last + * request to complete, idle GPU, verify a guc_id was stolen via a counter, and + * exit the test. Test also artificially reduces the number of guc_ids so the + * test runs in a timely manner. + */ +static int intel_guc_steal_guc_ids(void *arg) +{ + struct intel_gt *gt = arg; + struct intel_guc *guc = >->uc.guc; + int ret, sv, context_index = 0; + intel_wakeref_t wakeref; + struct intel_engine_cs *engine; + struct intel_context **ce; + struct igt_spinner spin; + struct i915_request *spin_rq = NULL, *rq, *last = NULL; + int number_guc_id_stolen = guc->number_guc_id_stolen; + + ce = kzalloc(sizeof(*ce) * GUC_MAX_LRC_DESCRIPTORS, GFP_KERNEL); + if (!ce) { + pr_err("Context array allocation failed\n"); + return -ENOMEM; + } + + wakeref = intel_runtime_pm_get(gt->uncore->rpm); + engine = intel_selftest_find_any_engine(gt); + sv = guc->submission_state.num_guc_ids; + guc->submission_state.num_guc_ids = 4096; + + /* Create spinner to block requests in below loop */ + ce[context_index] = intel_context_create(engine); + if (IS_ERR(ce[context_index])) { + ret = PTR_ERR(ce[context_index]); + ce[context_index] = NULL; + pr_err("Failed to create context: %d\n", ret); + goto err_wakeref; + } + ret = igt_spinner_init(&spin, engine->gt); + if (ret) { + pr_err("Failed to create spinner: %d\n", ret); + goto err_contexts; + } + spin_rq = igt_spinner_create_request(&spin, ce[context_index], + MI_ARB_CHECK); + if (IS_ERR(spin_rq)) { + ret = PTR_ERR(spin_rq); + pr_err("Failed to create spinner request: %d\n", ret); + goto err_contexts; + } + ret = request_add_spin(spin_rq, &spin); + if (ret) { + pr_err("Failed to add Spinner request: %d\n", ret); + goto err_spin_rq; + } + + /* Use all guc_ids */ + while (ret != -EAGAIN) { + ce[++context_index] = intel_context_create(engine); + if (IS_ERR(ce[context_index])) { + ret = PTR_ERR(ce[context_index--]); + ce[context_index] = NULL; + pr_err("Failed to create context: %d\n", ret); + goto err_spin_rq; + } + + rq = nop_user_request(ce[context_index], spin_rq); + if (IS_ERR(rq)) { + ret = PTR_ERR(rq); + rq = NULL; + if (ret != -EAGAIN) { + pr_err("Failed to create request, %d: %d\n", + context_index, ret); + goto err_spin_rq; + } + } else { + if (last) + i915_request_put(last); + last = rq; + } + } + + /* Release blocked requests */ + igt_spinner_end(&spin); + ret = intel_selftest_wait_for_rq(spin_rq); + if (ret) { + pr_err("Spin request failed to complete: %d\n", ret); + i915_request_put(last); + goto err_spin_rq; + } + i915_request_put(spin_rq); + igt_spinner_fini(&spin); + spin_rq = NULL; + + /* Wait for last request */ + ret = i915_request_wait(last, 0, HZ * 30); + i915_request_put(last); + if (ret < 0) { + pr_err("Last request failed to complete: %d\n", ret); + goto err_spin_rq; + } + + /* Try to steal guc_id */ + rq = nop_user_request(ce[context_index], NULL); + if (IS_ERR(rq)) { + ret = PTR_ERR(rq); + pr_err("Failed to steal guc_id, %d: %d\n", context_index, ret); + goto err_spin_rq; + } + + /* Wait for request with stolen guc_id */ + ret = i915_request_wait(rq, 0, HZ); + i915_request_put(rq); + if (ret < 0) { + pr_err("Request with stolen guc_id failed to complete: %d\n", + ret); + goto err_spin_rq; + } + + /* Wait for idle */ + ret = intel_gt_wait_for_idle(gt, HZ * 30); + if (ret < 0) { + pr_err("GT failed to idle: %d\n", ret); + goto err_spin_rq; + } + + /* Verify a guc_id was stolen */ + if (guc->number_guc_id_stolen == number_guc_id_stolen) { + pr_err("No guc_id was stolen"); + ret = -EINVAL; + } else { + ret = 0; + } + +err_spin_rq: + if (spin_rq) { + igt_spinner_end(&spin); + intel_selftest_wait_for_rq(spin_rq); + i915_request_put(spin_rq); + igt_spinner_fini(&spin); + intel_gt_wait_for_idle(gt, HZ * 30); + } +err_contexts: + for (; context_index >= 0 && ce[context_index]; --context_index) + intel_context_put(ce[context_index]); +err_wakeref: + intel_runtime_pm_put(gt->uncore->rpm, wakeref); + kfree(ce); + guc->submission_state.num_guc_ids = sv; + + return ret; +} + int intel_guc_live_selftests(struct drm_i915_private *i915) { static const struct i915_subtest tests[] = { SUBTEST(intel_guc_scrub_ctbs), + SUBTEST(intel_guc_steal_guc_ids), }; struct intel_gt *gt = &i915->gt;