From 54c204c522fd2a887b52c7672b9238903ba59a8b Mon Sep 17 00:00:00 2001 From: Matthew Auld Date: Fri, 19 Aug 2022 13:39:04 +0100 Subject: [PATCH] Revert "drm/i915/guc: Add delay to disable scheduling after pin count goes to zero" This reverts commit 6a079903847cce1dd06345127d2a32f26d2cd9c6. Everything in CI using GuC is now timing out[1], and killing the machine with this change (perhaps a deadlock?). CI was recently on fire due to some changes coming in from -rc1, so likely the pre-merge CI results for this series were invalid? For now just revert, unless GuC experts already have a fix in mind. [1] https://intel-gfx-ci.01.org/tree/drm-tip/index.html? Signed-off-by: Matthew Auld Cc: Matthew Brost Cc: Alan Previn Cc: John Harrison Reviewed-by: John Harrison Signed-off-by: Lucas De Marchi Link: https://patchwork.freedesktop.org/patch/msgid/20220819123904.913750-1-matthew.auld@intel.com --- drivers/gpu/drm/i915/gem/i915_gem_context.c | 2 +- drivers/gpu/drm/i915/gt/intel_context.h | 8 -- drivers/gpu/drm/i915/gt/intel_context_types.h | 7 - drivers/gpu/drm/i915/gt/uc/intel_guc.h | 17 +-- drivers/gpu/drm/i915/gt/uc/intel_guc_debugfs.c | 60 --------- drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 154 ++++------------------ drivers/gpu/drm/i915/i915_selftest.h | 2 - 7 files changed, 27 insertions(+), 223 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c index df7fd1b..dabdfe09 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c @@ -1454,7 +1454,7 @@ static void engines_idle_release(struct i915_gem_context *ctx, int err; /* serialises with execbuf */ - intel_context_close(ce); + set_bit(CONTEXT_CLOSED_BIT, &ce->flags); if (!intel_context_pin_if_active(ce)) continue; diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915/gt/intel_context.h index f96420f..8e2d706 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.h +++ b/drivers/gpu/drm/i915/gt/intel_context.h @@ -276,14 +276,6 @@ static inline bool intel_context_is_barrier(const struct intel_context *ce) return test_bit(CONTEXT_BARRIER_BIT, &ce->flags); } -static inline void intel_context_close(struct intel_context *ce) -{ - set_bit(CONTEXT_CLOSED_BIT, &ce->flags); - - if (ce->ops->close) - ce->ops->close(ce); -} - static inline bool intel_context_is_closed(const struct intel_context *ce) { return test_bit(CONTEXT_CLOSED_BIT, &ce->flags); diff --git a/drivers/gpu/drm/i915/gt/intel_context_types.h b/drivers/gpu/drm/i915/gt/intel_context_types.h index 86ac84e..04eacae 100644 --- a/drivers/gpu/drm/i915/gt/intel_context_types.h +++ b/drivers/gpu/drm/i915/gt/intel_context_types.h @@ -43,8 +43,6 @@ struct intel_context_ops { void (*revoke)(struct intel_context *ce, struct i915_request *rq, unsigned int preempt_timeout_ms); - void (*close)(struct intel_context *ce); - int (*pre_pin)(struct intel_context *ce, struct i915_gem_ww_ctx *ww, void **vaddr); int (*pin)(struct intel_context *ce, void *vaddr); void (*unpin)(struct intel_context *ce); @@ -210,11 +208,6 @@ struct intel_context { * each priority bucket */ u32 prio_count[GUC_CLIENT_PRIORITY_NUM]; - /** - * @sched_disable_delay: worker to disable scheduling on this - * context - */ - struct delayed_work sched_disable_delay; } guc_state; struct { diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h index 944b549..804133d 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc.h +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.h @@ -113,10 +113,6 @@ struct intel_guc { */ struct list_head guc_id_list; /** - * @guc_ids_in_use: Number single-lrc guc_ids in use - */ - u16 guc_ids_in_use; - /** * @destroyed_contexts: list of contexts waiting to be destroyed * (deregistered with the GuC) */ @@ -136,16 +132,6 @@ struct intel_guc { * @reset_fail_mask: mask of engines that failed to reset */ intel_engine_mask_t reset_fail_mask; - /** - * @sched_disable_delay_ms: schedule disable delay, in ms, for - * contexts - */ - u64 sched_disable_delay_ms; - /** - * @sched_disable_gucid_threshold: threshold of min remaining available - * guc_ids before we start bypassing the schedule disable delay - */ - int sched_disable_gucid_threshold; } submission_state; /** @@ -475,10 +461,9 @@ void intel_guc_submission_reset_finish(struct intel_guc *guc); void intel_guc_submission_cancel_requests(struct intel_guc *guc); void intel_guc_load_status(struct intel_guc *guc, struct drm_printer *p); -void intel_guc_dump_time_info(struct intel_guc *guc, struct drm_printer *p); void intel_guc_write_barrier(struct intel_guc *guc); -int intel_guc_sched_disable_gucid_threshold_max(struct intel_guc *guc); +void intel_guc_dump_time_info(struct intel_guc *guc, struct drm_printer *p); #endif diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_debugfs.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_debugfs.c index c91b150..25f09a4 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_debugfs.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_debugfs.c @@ -71,72 +71,12 @@ static bool intel_eval_slpc_support(void *data) return intel_guc_slpc_is_used(guc); } -static int guc_sched_disable_delay_ms_get(void *data, u64 *val) -{ - struct intel_guc *guc = data; - - if (!intel_guc_submission_is_used(guc)) - return -ENODEV; - - *val = guc->submission_state.sched_disable_delay_ms; - - return 0; -} - -static int guc_sched_disable_delay_ms_set(void *data, u64 val) -{ - struct intel_guc *guc = data; - - if (!intel_guc_submission_is_used(guc)) - return -ENODEV; - - guc->submission_state.sched_disable_delay_ms = val; - - return 0; -} -DEFINE_SIMPLE_ATTRIBUTE(guc_sched_disable_delay_ms_fops, - guc_sched_disable_delay_ms_get, - guc_sched_disable_delay_ms_set, "%lld\n"); - -static int guc_sched_disable_gucid_threshold_get(void *data, u64 *val) -{ - struct intel_guc *guc = data; - - if (!intel_guc_submission_is_used(guc)) - return -ENODEV; - - *val = guc->submission_state.sched_disable_gucid_threshold; - return 0; -} - -static int guc_sched_disable_gucid_threshold_set(void *data, u64 val) -{ - struct intel_guc *guc = data; - - if (!intel_guc_submission_is_used(guc)) - return -ENODEV; - - if (val > intel_guc_sched_disable_gucid_threshold_max(guc)) - guc->submission_state.sched_disable_gucid_threshold = - intel_guc_sched_disable_gucid_threshold_max(guc); - else - guc->submission_state.sched_disable_gucid_threshold = val; - - return 0; -} -DEFINE_SIMPLE_ATTRIBUTE(guc_sched_disable_gucid_threshold_fops, - guc_sched_disable_gucid_threshold_get, - guc_sched_disable_gucid_threshold_set, "%lld\n"); - void intel_guc_debugfs_register(struct intel_guc *guc, struct dentry *root) { static const struct intel_gt_debugfs_file files[] = { { "guc_info", &guc_info_fops, NULL }, { "guc_registered_contexts", &guc_registered_contexts_fops, NULL }, { "guc_slpc_info", &guc_slpc_info_fops, &intel_eval_slpc_support}, - { "guc_sched_disable_delay_ms", &guc_sched_disable_delay_ms_fops, NULL }, - { "guc_sched_disable_gucid_threshold", &guc_sched_disable_gucid_threshold_fops, - NULL }, }; if (!intel_guc_is_supported(guc)) 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 a0cebb4..0d56b61 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -65,13 +65,7 @@ * corresponding G2H returns indicating the scheduling disable operation has * completed it is safe to unpin the context. While a disable is in flight it * isn't safe to resubmit the context so a fence is used to stall all future - * requests of that context until the G2H is returned. Because this interaction - * with the GuC takes a non-zero amount of time we delay the disabling of - * scheduling after the pin count goes to zero by a configurable period of time - * (see SCHED_DISABLE_DELAY_MS). The thought is this gives the user a window of - * time to resubmit something on the context before doing this costly operation. - * This delay is only done if the context isn't closed and the guc_id usage is - * less than a threshold (see NUM_SCHED_DISABLE_GUC_IDS_THRESHOLD). + * requests of that context until the G2H is returned. * * Context deregistration: * Before a context can be destroyed or if we steal its guc_id we must @@ -1995,9 +1989,6 @@ static int new_guc_id(struct intel_guc *guc, struct intel_context *ce) if (unlikely(ret < 0)) return ret; - if (!intel_context_is_parent(ce)) - ++guc->submission_state.guc_ids_in_use; - ce->guc_id.id = ret; return 0; } @@ -2007,16 +1998,14 @@ 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)) { - if (intel_context_is_parent(ce)) { + 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 { - --guc->submission_state.guc_ids_in_use; + else ida_simple_remove(&guc->submission_state.guc_ids, ce->guc_id.id); - } clr_ctx_id_mapping(guc, ce->guc_id.id); set_context_guc_id_invalid(ce); } @@ -3004,98 +2993,41 @@ guc_context_revoke(struct intel_context *ce, struct i915_request *rq, } } -static void guc_context_sched_disable(struct intel_context *ce); - -static void do_sched_disable(struct intel_guc *guc, struct intel_context *ce, - unsigned long flags) - __releases(ce->guc_state.lock) +static void guc_context_sched_disable(struct intel_context *ce) { + struct intel_guc *guc = ce_to_guc(ce); + unsigned long flags; struct intel_runtime_pm *runtime_pm = &ce->engine->gt->i915->runtime_pm; intel_wakeref_t wakeref; + u16 guc_id; - lockdep_assert_held(&ce->guc_state.lock); - - spin_unlock_irqrestore(&ce->guc_state.lock, flags); - - with_intel_runtime_pm(runtime_pm, wakeref) - guc_context_sched_disable(ce); -} - -static bool bypass_sched_disable(struct intel_guc *guc, - struct intel_context *ce) -{ - lockdep_assert_held(&ce->guc_state.lock); GEM_BUG_ON(intel_context_is_child(ce)); - if (submission_disabled(guc) || context_guc_id_invalid(ce) || - !ctx_id_mapped(guc, ce->guc_id.id)) { - clr_context_enabled(ce); - return true; - } - - return !context_enabled(ce); -} - -static void __delay_sched_disable(struct work_struct *wrk) -{ - struct intel_context *ce = - container_of(wrk, typeof(*ce), guc_state.sched_disable_delay.work); - struct intel_guc *guc = ce_to_guc(ce); - unsigned long flags; - spin_lock_irqsave(&ce->guc_state.lock, flags); - if (bypass_sched_disable(guc, ce)) { - spin_unlock_irqrestore(&ce->guc_state.lock, flags); - intel_context_sched_disable_unpin(ce); - } else { - do_sched_disable(guc, ce, flags); - } -} - -static bool guc_id_pressure(struct intel_guc *guc, struct intel_context *ce) -{ - /* - * parent contexts are perma-pinned, if we are unpinning do schedule - * disable immediately. - */ - if (intel_context_is_parent(ce)) - return true; - /* - * If we are beyond the threshold for avail guc_ids, do schedule disable immediately. + * We have to check if the context has been disabled by another thread, + * check if submssion has been disabled to seal a race with reset and + * finally check if any more requests have been committed to the + * context ensursing that a request doesn't slip through the + * 'context_pending_disable' fence. */ - return guc->submission_state.guc_ids_in_use > - guc->submission_state.sched_disable_gucid_threshold; -} - -static void guc_context_sched_disable(struct intel_context *ce) -{ - struct intel_guc *guc = ce_to_guc(ce); - u64 delay = guc->submission_state.sched_disable_delay_ms; - unsigned long flags; - - spin_lock_irqsave(&ce->guc_state.lock, flags); - - if (bypass_sched_disable(guc, ce)) { - spin_unlock_irqrestore(&ce->guc_state.lock, flags); - intel_context_sched_disable_unpin(ce); - } else if (!intel_context_is_closed(ce) && !guc_id_pressure(guc, ce) && - delay) { + if (unlikely(!context_enabled(ce) || submission_disabled(guc) || + context_has_committed_requests(ce))) { + clr_context_enabled(ce); spin_unlock_irqrestore(&ce->guc_state.lock, flags); - mod_delayed_work(system_unbound_wq, - &ce->guc_state.sched_disable_delay, - msecs_to_jiffies(delay)); - } else { - do_sched_disable(guc, ce, flags); + goto unpin; } -} + guc_id = prep_context_pending_disable(ce); -static void guc_context_close(struct intel_context *ce) -{ - if (test_bit(CONTEXT_GUC_INIT, &ce->flags) && - cancel_delayed_work(&ce->guc_state.sched_disable_delay)) - __delay_sched_disable(&ce->guc_state.sched_disable_delay.work); + spin_unlock_irqrestore(&ce->guc_state.lock, flags); + + with_intel_runtime_pm(runtime_pm, wakeref) + __guc_context_sched_disable(guc, ce, guc_id); + + return; +unpin: + intel_context_sched_disable_unpin(ce); } static inline void guc_lrc_desc_unpin(struct intel_context *ce) @@ -3414,8 +3346,6 @@ static void remove_from_context(struct i915_request *rq) static const struct intel_context_ops guc_context_ops = { .alloc = guc_context_alloc, - .close = guc_context_close, - .pre_pin = guc_context_pre_pin, .pin = guc_context_pin, .unpin = guc_context_unpin, @@ -3498,10 +3428,6 @@ static void guc_context_init(struct intel_context *ce) rcu_read_unlock(); ce->guc_state.prio = map_i915_prio_to_guc_prio(prio); - - INIT_DELAYED_WORK(&ce->guc_state.sched_disable_delay, - __delay_sched_disable); - set_bit(CONTEXT_GUC_INIT, &ce->flags); } @@ -3539,9 +3465,6 @@ static int guc_request_alloc(struct i915_request *rq) if (unlikely(!test_bit(CONTEXT_GUC_INIT, &ce->flags))) guc_context_init(ce); - if (cancel_delayed_work(&ce->guc_state.sched_disable_delay)) - intel_context_sched_disable_unpin(ce); - /* * Call pin_guc_id here rather than in the pinning step as with * dma_resv, contexts can be repeatedly pinned / unpinned trashing the @@ -3672,8 +3595,6 @@ static int guc_virtual_context_alloc(struct intel_context *ce) static const struct intel_context_ops virtual_guc_context_ops = { .alloc = guc_virtual_context_alloc, - .close = guc_context_close, - .pre_pin = guc_virtual_context_pre_pin, .pin = guc_virtual_context_pin, .unpin = guc_virtual_context_unpin, @@ -3763,8 +3684,6 @@ static void guc_child_context_destroy(struct kref *kref) static const struct intel_context_ops virtual_parent_context_ops = { .alloc = guc_virtual_context_alloc, - .close = guc_context_close, - .pre_pin = guc_context_pre_pin, .pin = guc_parent_context_pin, .unpin = guc_parent_context_unpin, @@ -4295,26 +4214,6 @@ static bool __guc_submission_selected(struct intel_guc *guc) return i915->params.enable_guc & ENABLE_GUC_SUBMISSION; } -int intel_guc_sched_disable_gucid_threshold_max(struct intel_guc *guc) -{ - return guc->submission_state.num_guc_ids - NUMBER_MULTI_LRC_GUC_ID(guc); -} - -/* - * This default value of 33 milisecs (+1 milisec round up) ensures 30fps or higher - * workloads are able to enjoy the latency reduction when delaying the schedule-disable - * operation. This matches the 30fps game-render + encode (real world) workload this - * knob was tested against. - */ -#define SCHED_DISABLE_DELAY_MS 34 - -/* - * A threshold of 75% is a reasonable starting point considering that real world apps - * generally don't get anywhere near this. - */ -#define NUM_SCHED_DISABLE_GUCIDS_DEFAULT_THRESHOLD(__guc) \ - (((intel_guc_sched_disable_gucid_threshold_max(guc)) * 3) / 4) - void intel_guc_submission_init_early(struct intel_guc *guc) { xa_init_flags(&guc->context_lookup, XA_FLAGS_LOCK_IRQ); @@ -4331,10 +4230,7 @@ void intel_guc_submission_init_early(struct intel_guc *guc) spin_lock_init(&guc->timestamp.lock); INIT_DELAYED_WORK(&guc->timestamp.work, guc_timestamp_ping); - guc->submission_state.sched_disable_delay_ms = SCHED_DISABLE_DELAY_MS; guc->submission_state.num_guc_ids = GUC_MAX_CONTEXT_ID; - guc->submission_state.sched_disable_gucid_threshold = - NUM_SCHED_DISABLE_GUCIDS_DEFAULT_THRESHOLD(guc); guc->submission_supported = __guc_submission_supported(guc); guc->submission_selected = __guc_submission_selected(guc); } diff --git a/drivers/gpu/drm/i915/i915_selftest.h b/drivers/gpu/drm/i915/i915_selftest.h index bdf3e22..f54de04 100644 --- a/drivers/gpu/drm/i915/i915_selftest.h +++ b/drivers/gpu/drm/i915/i915_selftest.h @@ -92,14 +92,12 @@ int __i915_subtests(const char *caller, T, ARRAY_SIZE(T), data) #define i915_live_subtests(T, data) ({ \ typecheck(struct drm_i915_private *, data); \ - (data)->gt[0]->uc.guc.submission_state.sched_disable_delay_ms = 0; \ __i915_subtests(__func__, \ __i915_live_setup, __i915_live_teardown, \ T, ARRAY_SIZE(T), data); \ }) #define intel_gt_live_subtests(T, data) ({ \ typecheck(struct intel_gt *, data); \ - (data)->uc.guc.submission_state.sched_disable_delay_ms = 0; \ __i915_subtests(__func__, \ __intel_gt_live_setup, __intel_gt_live_teardown, \ T, ARRAY_SIZE(T), data); \ -- 2.7.4