From e12ab16907252ebc3ec956932eb40ed88105346b Mon Sep 17 00:00:00 2001 From: Dave Gordon Date: Thu, 26 Oct 2017 16:17:37 +0200 Subject: [PATCH] drm/i915/guc: Add a second client, to be used for preemption MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This second client is created with priority KMD_HIGH, and marked as preemptive. This will allow us to request preemption using GuC actions. v2: Extract clients creation into a helper, debugfs fixups. (Michał) Recreate doorbell on init. (Daniele) Move clients into an array. v3: And move clients back from an array, to get rid of the enum (Michał) v4: Use is_high_priority, move DRM_ERROR into __create_doorbell, move GEM_BUG_ON inside guc_clients_create (Michał) v5: Split the BUG_ON (Michał) v6: Cleanup after error during doorbell reinit (Michał) Signed-off-by: Dave Gordon Signed-off-by: Michał Winiarski Cc: Chris Wilson Cc: Daniele Ceraolo Spurio Cc: Jeff McGee Cc: Michal Wajdeczko Cc: Oscar Mateo Reviewed-by: Michal Wajdeczko Signed-off-by: Chris Wilson Link: https://patchwork.freedesktop.org/patch/msgid/20171026141737.31656-1-michal.winiarski@intel.com --- drivers/gpu/drm/i915/i915_debugfs.c | 2 + drivers/gpu/drm/i915/i915_guc_submission.c | 118 ++++++++++++++++++++--------- drivers/gpu/drm/i915/intel_guc.h | 1 + 3 files changed, 86 insertions(+), 35 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 34862aa..c1e5bba 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -2484,6 +2484,8 @@ static int i915_guc_info(struct seq_file *m, void *data) seq_printf(m, "\nGuC execbuf client @ %p:\n", guc->execbuf_client); i915_guc_client_info(m, dev_priv, guc->execbuf_client); + seq_printf(m, "\nGuC preempt client @ %p:\n", guc->preempt_client); + i915_guc_client_info(m, dev_priv, guc->preempt_client); i915_guc_log_info(m, dev_priv); diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c index d1a5613..b0f034f 100644 --- a/drivers/gpu/drm/i915/i915_guc_submission.c +++ b/drivers/gpu/drm/i915/i915_guc_submission.c @@ -33,10 +33,11 @@ * * GuC client: * A i915_guc_client refers to a submission path through GuC. Currently, there - * is only one of these (the execbuf_client) and this one is charged with all - * submissions to the GuC. This struct is the owner of a doorbell, a process - * descriptor and a workqueue (all of them inside a single gem object that - * contains all required pages for these elements). + * are two clients. One of them (the execbuf_client) is charged with all + * submissions to the GuC, the other one (preempt_client) is responsible for + * preempting the execbuf_client. This struct is the owner of a doorbell, a + * process descriptor and a workqueue (all of them inside a single gem object + * that contains all required pages for these elements). * * GuC stage descriptor: * During initialization, the driver allocates a static pool of 1024 such @@ -83,7 +84,8 @@ static inline bool is_high_priority(struct i915_guc_client* client) { - return client->priority <= GUC_CLIENT_PRIORITY_HIGH; + return (client->priority == GUC_CLIENT_PRIORITY_KMD_HIGH || + client->priority == GUC_CLIENT_PRIORITY_HIGH); } static int __reserve_doorbell(struct i915_guc_client *client) @@ -196,8 +198,11 @@ static int __create_doorbell(struct i915_guc_client *client) doorbell->cookie = 0; err = __guc_allocate_doorbell(client->guc, client->stage_id); - if (err) + if (err) { doorbell->db_status = GUC_DOORBELL_DISABLED; + DRM_ERROR("Couldn't create client %u doorbell: %d\n", + client->stage_id, err); + } return err; } @@ -363,6 +368,8 @@ static void guc_stage_desc_init(struct intel_guc *guc, memset(desc, 0, sizeof(*desc)); desc->attribute = GUC_STAGE_DESC_ATTR_ACTIVE | GUC_STAGE_DESC_ATTR_KERNEL; + if (is_high_priority(client)) + desc->attribute |= GUC_STAGE_DESC_ATTR_PREEMPT; desc->stage_id = client->stage_id; desc->priority = client->priority; desc->db_id = client->doorbell_id; @@ -763,14 +770,14 @@ static int guc_init_doorbell_hw(struct intel_guc *guc) /* Now for every client (and not only execbuf_client) make sure their * doorbells are known by the GuC */ - //for (client = client_list; client != NULL; client = client->next) - { - ret = __create_doorbell(client); - if (ret) { - DRM_ERROR("Couldn't recreate client %u doorbell: %d\n", - client->stage_id, ret); - return ret; - } + ret = __create_doorbell(guc->execbuf_client); + if (ret) + return ret; + + ret = __create_doorbell(guc->preempt_client); + if (ret) { + __destroy_doorbell(guc->execbuf_client); + return ret; } /* Read back & verify all (used & unused) doorbell registers */ @@ -895,6 +902,50 @@ static void guc_client_free(struct i915_guc_client *client) kfree(client); } +static int guc_clients_create(struct intel_guc *guc) +{ + struct drm_i915_private *dev_priv = guc_to_i915(guc); + struct i915_guc_client *client; + + GEM_BUG_ON(guc->execbuf_client); + GEM_BUG_ON(guc->preempt_client); + + client = guc_client_alloc(dev_priv, + INTEL_INFO(dev_priv)->ring_mask, + GUC_CLIENT_PRIORITY_KMD_NORMAL, + dev_priv->kernel_context); + if (IS_ERR(client)) { + DRM_ERROR("Failed to create GuC client for submission!\n"); + return PTR_ERR(client); + } + guc->execbuf_client = client; + + client = guc_client_alloc(dev_priv, + INTEL_INFO(dev_priv)->ring_mask, + GUC_CLIENT_PRIORITY_KMD_HIGH, + dev_priv->preempt_context); + if (IS_ERR(client)) { + DRM_ERROR("Failed to create GuC client for preemption!\n"); + guc_client_free(guc->execbuf_client); + guc->execbuf_client = NULL; + return PTR_ERR(client); + } + guc->preempt_client = client; + + return 0; +} + +static void guc_clients_destroy(struct intel_guc *guc) +{ + struct i915_guc_client *client; + + client = fetch_and_zero(&guc->execbuf_client); + guc_client_free(client); + + client = fetch_and_zero(&guc->preempt_client); + guc_client_free(client); +} + static void guc_policy_init(struct guc_policy *policy) { policy->execution_quantum = POLICY_DEFAULT_EXECUTION_QUANTUM_US; @@ -1134,7 +1185,6 @@ static void i915_guc_submission_unpark(struct intel_engine_cs *engine) int i915_guc_submission_enable(struct drm_i915_private *dev_priv) { struct intel_guc *guc = &dev_priv->guc; - struct i915_guc_client *client = guc->execbuf_client; struct intel_engine_cs *engine; enum intel_engine_id id; int err; @@ -1152,28 +1202,28 @@ int i915_guc_submission_enable(struct drm_i915_private *dev_priv) sizeof(struct guc_wq_item) * I915_NUM_ENGINES > GUC_WQ_SIZE); - if (!client) { - client = guc_client_alloc(dev_priv, - INTEL_INFO(dev_priv)->ring_mask, - GUC_CLIENT_PRIORITY_KMD_NORMAL, - dev_priv->kernel_context); - if (IS_ERR(client)) { - DRM_ERROR("Failed to create GuC client for execbuf!\n"); - return PTR_ERR(client); - } - - guc->execbuf_client = client; + /* + * We're being called on both module initialization and on reset, + * until this flow is changed, we're using regular client presence to + * determine which case are we in, and whether we should allocate new + * clients or just reset their workqueues. + */ + if (!guc->execbuf_client) { + err = guc_clients_create(guc); + if (err) + return err; + } else { + guc_reset_wq(guc->execbuf_client); + guc_reset_wq(guc->preempt_client); } err = intel_guc_sample_forcewake(guc); if (err) - goto err_execbuf_client; - - guc_reset_wq(client); + goto err_free_clients; err = guc_init_doorbell_hw(guc); if (err) - goto err_execbuf_client; + goto err_free_clients; /* Take over from manual control of ELSP (execlists) */ guc_interrupts_capture(dev_priv); @@ -1187,9 +1237,8 @@ int i915_guc_submission_enable(struct drm_i915_private *dev_priv) return 0; -err_execbuf_client: - guc_client_free(guc->execbuf_client); - guc->execbuf_client = NULL; +err_free_clients: + guc_clients_destroy(guc); return err; } @@ -1204,6 +1253,5 @@ void i915_guc_submission_disable(struct drm_i915_private *dev_priv) /* Revert back to manual ELSP submission */ intel_engines_reset_default_submission(dev_priv); - guc_client_free(guc->execbuf_client); - guc->execbuf_client = NULL; + guc_clients_destroy(guc); } diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h index aa15831..6ca55c5 100644 --- a/drivers/gpu/drm/i915/intel_guc.h +++ b/drivers/gpu/drm/i915/intel_guc.h @@ -58,6 +58,7 @@ struct intel_guc { void *shared_data_vaddr; struct i915_guc_client *execbuf_client; + struct i915_guc_client *preempt_client; DECLARE_BITMAP(doorbell_bitmap, GUC_NUM_DOORBELLS); /* Cyclic counter mod pagesize */ -- 2.7.4