On Fri, Dec 10, 2021 at 05:33:02PM -0800, John Harrison wrote:
> On 12/10/2021 16:56, Matthew Brost wrote:
> > Testing the stealing of guc ids is hard from user spaec as we have 64k
> spaec -> space
>
> > guc_ids. Add a selftest, which artificially reduces the number of guc
> > ids, and forces a steal. Details of test has comment in code so will not
> has -> are
>
> But would a copy&paste really be so hard? It is useful to be able to read
> what a patch does from the commit log and not have to delve inside every
> time.
>
>
> > repeat here.
> >
> > Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/gt/uc/intel_guc.h | 12 ++
> > .../gpu/drm/i915/gt/uc/intel_guc_submission.c | 15 +-
> > drivers/gpu/drm/i915/gt/uc/selftest_guc.c | 171 ++++++++++++++++++
> > 3 files changed, 193 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..307380a2e2ff 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 of test.
> of test -> while testing
>
> Should have a CONFIG_SELFTEST around it? And define a wrapper that is
> GUC_MAX_LRC_DESCRIPTORS or num_guc_ids as appropriate.
>
Missed this. Basically decided again a SELFTEST wrapper because SRIOV
needs this anyways. Can hide this if you insist.
Matt
>
> > + */
> > + 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_stole: The number of guc_ids that have been stole
> > + */
> > + int number_guc_id_stole;
> stole -> stolen (in all three cases)
>
> > +#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..57019b190bfb 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 +145,7 @@ 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)
> And keep the original definition for the non CONFIG_SELFTEST case?
>
> > /*
> > * Below is a set of functions which control the GuC scheduling state which
> > @@ -1775,7 +1775,7 @@ 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 +1869,13 @@ 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 +1941,10 @@ 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_stole++;
> > +#endif
> > +
> > return 0;
> > } else {
> > return -EAGAIN;
> > @@ -3779,6 +3783,7 @@ 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..9ab355e64b3f 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 +123,168 @@ 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 to which is used as to block all subsequent
> to which -> which
> as to block -> to block
>
> > + * 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 completed unblocking all requests created in
> spinner is ended,
>
> > + * 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 guc_id was stole via counter,
> stole -> stolen
>
> > + * and exit 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, i = 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_stole = guc->number_guc_id_stole;
> stole -> 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[i++] = intel_context_create(engine);
> > + if (IS_ERR(ce[i - 1])) {
> > + ce[i - 1] = NULL;
> > + ret = PTR_ERR(ce[i - 1]);
> Would be less peculiar looking to do the i++ after the if statement.
>
> > + 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[i - 1], 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[i++] = intel_context_create(engine);
> > + if (IS_ERR(ce[i - 1])) {
> > + ce[i - 1] = NULL;
> > + ret = PTR_ERR(ce[i - 1]);
> > + pr_err("Failed to create context: %d\n", ret);
> > + goto err_spin_rq;
> Won't this try to put the null context? Or rather will see the null context
> and immediately abort the clean up loop. Need to do the i++ after the if
> statement. Or after the nop_user_request call to get rid of all the ce[i -
> 1] things.
>
> John.
>
> > + }
> > +
> > + rq = nop_user_request(ce[i - 1], spin_rq);
> > + if (IS_ERR(rq)) {
> > + ret = PTR_ERR(rq);
> > + rq = NULL;
> > + if (ret != -EAGAIN) {
> > + pr_err("Failed to create request, %d: %d\n", i,
> > + 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[i - 1], NULL);
> > + if (IS_ERR(rq)) {
> > + ret = PTR_ERR(rq);
> > + pr_err("Failed to steal guc_id, %d: %d\n", i, ret);
> > + goto err_spin_rq;
> > + }
> > +
> > + /* Wait for last request */
> > + ret = i915_request_wait(rq, 0, HZ);
> > + i915_request_put(rq);
> > + if (ret < 0) {
> > + pr_err("Last request 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 got stole */
> > + if (guc->number_guc_id_stole == number_guc_id_stole) {
> > + pr_err("No guc_ids 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:
> > + while (i && ce[--i])
> > + intel_context_put(ce[i]);
> > +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;
>
