From 09c5e3a5e509bb10249c8252dc10c0d8a842e4ae Mon Sep 17 00:00:00 2001 From: Matthew Brost Date: Thu, 14 Oct 2021 10:19:50 -0700 Subject: [PATCH] drm/i915/guc: Assign contexts in parent-child relationship consecutive guc_ids Assign contexts in parent-child relationship consecutive guc_ids. This is accomplished by partitioning guc_id space between ones that need to be consecutive (1/16 available guc_ids) and ones that do not (15/16 of available guc_ids). The consecutive search is implemented via the bitmap API. This is a precursor to the full GuC multi-lrc implementation but aligns to how GuC mutli-lrc interface is defined - guc_ids must be consecutive when using the GuC multi-lrc interface. v2: (Daniel Vetter) - Explicitly state why we assign consecutive guc_ids v3: (John Harrison) - Bring back in spin lock Signed-off-by: Matthew Brost Reviewed-by: John Harrison Signed-off-by: John Harrison Link: https://patchwork.freedesktop.org/patch/msgid/20211014172005.27155-11-matthew.brost@intel.com --- drivers/gpu/drm/i915/gt/uc/intel_guc.h | 6 +- drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 104 +++++++++++++++++----- 2 files changed, 86 insertions(+), 24 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h index 74f071a..4ca197f 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h @@ -82,10 +82,14 @@ struct intel_guc { */ spinlock_t lock; /** - * @guc_ids: used to allocate new guc_ids + * @guc_ids: used to allocate new guc_ids, single-lrc */ struct ida guc_ids; /** + * @guc_ids_bitmap: used to allocate new guc_ids, multi-lrc + */ + unsigned long *guc_ids_bitmap; + /** * @guc_id_list: list of intel_context with valid guc_ids but no * refs */ 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 fbcf2dc..7ba4f1d 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -129,6 +129,16 @@ guc_create_virtual(struct intel_engine_cs **siblings, unsigned int count); #define GUC_REQUEST_SIZE 64 /* bytes */ /* + * We reserve 1/16 of the guc_ids for multi-lrc as these need to be contiguous + * per the GuC submission interface. A different allocation algorithm is used + * (bitmap vs. ida) between multi-lrc and single-lrc hence the reason to + * partition the guc_id space. We believe the number of multi-lrc contexts in + * 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) + +/* * Below is a set of functions which control the GuC scheduling state which * require a lock. */ @@ -1207,6 +1217,11 @@ int intel_guc_submission_init(struct intel_guc *guc) INIT_WORK(&guc->submission_state.destroyed_worker, destroyed_worker_func); + guc->submission_state.guc_ids_bitmap = + bitmap_zalloc(NUMBER_MULTI_LRC_GUC_ID, GFP_KERNEL); + if (!guc->submission_state.guc_ids_bitmap) + return -ENOMEM; + return 0; } @@ -1218,6 +1233,7 @@ void intel_guc_submission_fini(struct intel_guc *guc) guc_flush_destroyed_contexts(guc); guc_lrc_desc_pool_destroy(guc); i915_sched_engine_put(guc->sched_engine); + bitmap_free(guc->submission_state.guc_ids_bitmap); } static inline void queue_request(struct i915_sched_engine *sched_engine, @@ -1269,18 +1285,43 @@ static void guc_submit_request(struct i915_request *rq) spin_unlock_irqrestore(&sched_engine->lock, flags); } -static int new_guc_id(struct intel_guc *guc) +static int new_guc_id(struct intel_guc *guc, struct intel_context *ce) { - return ida_simple_get(&guc->submission_state.guc_ids, 0, - GUC_MAX_LRC_DESCRIPTORS, GFP_KERNEL | - __GFP_RETRY_MAYFAIL | __GFP_NOWARN); + int ret; + + GEM_BUG_ON(intel_context_is_child(ce)); + + if (intel_context_is_parent(ce)) + ret = bitmap_find_free_region(guc->submission_state.guc_ids_bitmap, + NUMBER_MULTI_LRC_GUC_ID, + 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, + GFP_KERNEL | __GFP_RETRY_MAYFAIL | + __GFP_NOWARN); + if (unlikely(ret < 0)) + return ret; + + ce->guc_id.id = ret; + return 0; } static void __release_guc_id(struct intel_guc *guc, struct intel_context *ce) { + GEM_BUG_ON(intel_context_is_child(ce)); + if (!context_guc_id_invalid(ce)) { - ida_simple_remove(&guc->submission_state.guc_ids, - ce->guc_id.id); + if (intel_context_is_parent(ce)) + bitmap_release_region(guc->submission_state.guc_ids_bitmap, + ce->guc_id.id, + order_base_2(ce->parallel.number_children + + 1)); + else + ida_simple_remove(&guc->submission_state.guc_ids, + ce->guc_id.id); reset_lrc_desc(guc, ce->guc_id.id); set_context_guc_id_invalid(ce); } @@ -1297,49 +1338,64 @@ static void release_guc_id(struct intel_guc *guc, struct intel_context *ce) spin_unlock_irqrestore(&guc->submission_state.lock, flags); } -static int steal_guc_id(struct intel_guc *guc) +static int steal_guc_id(struct intel_guc *guc, struct intel_context *ce) { - struct intel_context *ce; - int guc_id; + struct intel_context *cn; lockdep_assert_held(&guc->submission_state.lock); + GEM_BUG_ON(intel_context_is_child(ce)); + GEM_BUG_ON(intel_context_is_parent(ce)); if (!list_empty(&guc->submission_state.guc_id_list)) { - ce = list_first_entry(&guc->submission_state.guc_id_list, + cn = list_first_entry(&guc->submission_state.guc_id_list, struct intel_context, guc_id.link); - GEM_BUG_ON(atomic_read(&ce->guc_id.ref)); - GEM_BUG_ON(context_guc_id_invalid(ce)); + GEM_BUG_ON(atomic_read(&cn->guc_id.ref)); + GEM_BUG_ON(context_guc_id_invalid(cn)); + GEM_BUG_ON(intel_context_is_child(cn)); + GEM_BUG_ON(intel_context_is_parent(cn)); - list_del_init(&ce->guc_id.link); - guc_id = ce->guc_id.id; + list_del_init(&cn->guc_id.link); + ce->guc_id = cn->guc_id; spin_lock(&ce->guc_state.lock); - clr_context_registered(ce); + clr_context_registered(cn); spin_unlock(&ce->guc_state.lock); - set_context_guc_id_invalid(ce); - return guc_id; + set_context_guc_id_invalid(cn); + + return 0; } else { return -EAGAIN; } } -static int assign_guc_id(struct intel_guc *guc, u16 *out) +static int assign_guc_id(struct intel_guc *guc, struct intel_context *ce) { int ret; lockdep_assert_held(&guc->submission_state.lock); + GEM_BUG_ON(intel_context_is_child(ce)); - ret = new_guc_id(guc); + ret = new_guc_id(guc, ce); if (unlikely(ret < 0)) { - ret = steal_guc_id(guc); + if (intel_context_is_parent(ce)) + return -ENOSPC; + + ret = steal_guc_id(guc, ce); if (ret < 0) return ret; } - *out = ret; + if (intel_context_is_parent(ce)) { + struct intel_context *child; + int i = 1; + + for_each_child(ce, child) + child->guc_id.id = ce->guc_id.id + i++; + } + return 0; } @@ -1357,7 +1413,7 @@ try_again: might_lock(&ce->guc_state.lock); if (context_guc_id_invalid(ce)) { - ret = assign_guc_id(guc, &ce->guc_id.id); + ret = assign_guc_id(guc, ce); if (ret) goto out_unlock; ret = 1; /* Indidcates newly assigned guc_id */ @@ -1399,8 +1455,10 @@ static void unpin_guc_id(struct intel_guc *guc, struct intel_context *ce) unsigned long flags; GEM_BUG_ON(atomic_read(&ce->guc_id.ref) < 0); + GEM_BUG_ON(intel_context_is_child(ce)); - if (unlikely(context_guc_id_invalid(ce))) + if (unlikely(context_guc_id_invalid(ce) || + intel_context_is_parent(ce))) return; spin_lock_irqsave(&guc->submission_state.lock, flags); -- 2.7.4