From 5507fcfa59b29eb46ab98d01fd4dcbaecf20d700 Mon Sep 17 00:00:00 2001 From: jsg Date: Fri, 10 Feb 2023 14:32:03 +0000 Subject: [PATCH] drm/i915: Fix up locking around dumping requests lists From John Harrison 04dcff26490cc8dedbfcf44cfb3e3e7a08622fd0 in linux-6.1.y/6.1.11 5bc4b43d5c6c9692ddc7b96116650cdf9406f3da in mainline linux --- sys/dev/pci/drm/i915/gt/intel_engine.h | 4 +- sys/dev/pci/drm/i915/gt/intel_engine_cs.c | 74 +++++++++---------- .../drm/i915/gt/intel_execlists_submission.c | 27 +++++++ .../drm/i915/gt/intel_execlists_submission.h | 4 + sys/dev/pci/drm/i915/i915_gpu_error.c | 26 +------ 5 files changed, 73 insertions(+), 62 deletions(-) diff --git a/sys/dev/pci/drm/i915/gt/intel_engine.h b/sys/dev/pci/drm/i915/gt/intel_engine.h index cbc8b857d5f..7a4504ea35c 100644 --- a/sys/dev/pci/drm/i915/gt/intel_engine.h +++ b/sys/dev/pci/drm/i915/gt/intel_engine.h @@ -248,8 +248,8 @@ void intel_engine_dump_active_requests(struct list_head *requests, ktime_t intel_engine_get_busy_time(struct intel_engine_cs *engine, ktime_t *now); -struct i915_request * -intel_engine_execlist_find_hung_request(struct intel_engine_cs *engine); +void intel_engine_get_hung_entity(struct intel_engine_cs *engine, + struct intel_context **ce, struct i915_request **rq); u32 intel_engine_context_size(struct intel_gt *gt, u8 class); struct intel_context * diff --git a/sys/dev/pci/drm/i915/gt/intel_engine_cs.c b/sys/dev/pci/drm/i915/gt/intel_engine_cs.c index 5ca6a8214fd..c8ae8682156 100644 --- a/sys/dev/pci/drm/i915/gt/intel_engine_cs.c +++ b/sys/dev/pci/drm/i915/gt/intel_engine_cs.c @@ -2085,17 +2085,6 @@ static void print_request_ring(struct drm_printer *m, struct i915_request *rq) } } -static unsigned long list_count(struct list_head *list) -{ - struct list_head *pos; - unsigned long count = 0; - - list_for_each(pos, list) - count++; - - return count; -} - static unsigned long read_ul(void *p, size_t x) { return *(unsigned long *)(p + x); @@ -2187,11 +2176,11 @@ void intel_engine_dump_active_requests(struct list_head *requests, } } -static void engine_dump_active_requests(struct intel_engine_cs *engine, struct drm_printer *m) +static void engine_dump_active_requests(struct intel_engine_cs *engine, + struct drm_printer *m) { + struct intel_context *hung_ce = NULL; struct i915_request *hung_rq = NULL; - struct intel_context *ce; - bool guc; /* * No need for an engine->irq_seqno_barrier() before the seqno reads. @@ -2200,29 +2189,20 @@ static void engine_dump_active_requests(struct intel_engine_cs *engine, struct d * But the intention here is just to report an instantaneous snapshot * so that's fine. */ - lockdep_assert_held(&engine->sched_engine->lock); + intel_engine_get_hung_entity(engine, &hung_ce, &hung_rq); drm_printf(m, "\tRequests:\n"); - guc = intel_uc_uses_guc_submission(&engine->gt->uc); - if (guc) { - ce = intel_engine_get_hung_context(engine); - if (ce) - hung_rq = intel_context_get_active_request(ce); - } else { - hung_rq = intel_engine_execlist_find_hung_request(engine); - if (hung_rq) - hung_rq = i915_request_get_rcu(hung_rq); - } - if (hung_rq) engine_dump_request(hung_rq, m, "\t\thung"); + else if (hung_ce) + drm_printf(m, "\t\tGot hung ce but no hung rq!\n"); - if (guc) + if (intel_uc_uses_guc_submission(&engine->gt->uc)) intel_guc_dump_active_requests(engine, hung_rq, m); else - intel_engine_dump_active_requests(&engine->sched_engine->requests, - hung_rq, m); + intel_execlists_dump_active_requests(engine, hung_rq, m); + if (hung_rq) i915_request_put(hung_rq); } @@ -2234,7 +2214,6 @@ void intel_engine_dump(struct intel_engine_cs *engine, struct i915_gpu_error * const error = &engine->i915->gpu_error; struct i915_request *rq; intel_wakeref_t wakeref; - unsigned long flags; ktime_t dummy; if (header) { @@ -2271,13 +2250,8 @@ void intel_engine_dump(struct intel_engine_cs *engine, i915_reset_count(error)); print_properties(engine, m); - spin_lock_irqsave(&engine->sched_engine->lock, flags); engine_dump_active_requests(engine, m); - drm_printf(m, "\tOn hold?: %lu\n", - list_count(&engine->sched_engine->hold)); - spin_unlock_irqrestore(&engine->sched_engine->lock, flags); - drm_printf(m, "\tMMIO base: 0x%08x\n", engine->mmio_base); wakeref = intel_runtime_pm_get_if_in_use(engine->uncore->rpm); if (wakeref) { @@ -2323,8 +2297,7 @@ intel_engine_create_virtual(struct intel_engine_cs **siblings, return siblings[0]->cops->create_virtual(siblings, count, flags); } -struct i915_request * -intel_engine_execlist_find_hung_request(struct intel_engine_cs *engine) +static struct i915_request *engine_execlist_find_hung_request(struct intel_engine_cs *engine) { struct i915_request *request, *active = NULL; @@ -2376,6 +2349,33 @@ intel_engine_execlist_find_hung_request(struct intel_engine_cs *engine) return active; } +void intel_engine_get_hung_entity(struct intel_engine_cs *engine, + struct intel_context **ce, struct i915_request **rq) +{ + unsigned long flags; + + *ce = intel_engine_get_hung_context(engine); + if (*ce) { + intel_engine_clear_hung_context(engine); + + *rq = intel_context_get_active_request(*ce); + return; + } + + /* + * Getting here with GuC enabled means it is a forced error capture + * with no actual hang. So, no need to attempt the execlist search. + */ + if (intel_uc_uses_guc_submission(&engine->gt->uc)) + return; + + spin_lock_irqsave(&engine->sched_engine->lock, flags); + *rq = engine_execlist_find_hung_request(engine); + if (*rq) + *rq = i915_request_get_rcu(*rq); + spin_unlock_irqrestore(&engine->sched_engine->lock, flags); +} + void xehp_enable_ccs_engines(struct intel_engine_cs *engine) { /* diff --git a/sys/dev/pci/drm/i915/gt/intel_execlists_submission.c b/sys/dev/pci/drm/i915/gt/intel_execlists_submission.c index 18116f1c7c9..682f9a6a6b1 100644 --- a/sys/dev/pci/drm/i915/gt/intel_execlists_submission.c +++ b/sys/dev/pci/drm/i915/gt/intel_execlists_submission.c @@ -4156,6 +4156,33 @@ void intel_execlists_show_requests(struct intel_engine_cs *engine, spin_unlock_irqrestore(&sched_engine->lock, flags); } +static unsigned long list_count(struct list_head *list) +{ + struct list_head *pos; + unsigned long count = 0; + + list_for_each(pos, list) + count++; + + return count; +} + +void intel_execlists_dump_active_requests(struct intel_engine_cs *engine, + struct i915_request *hung_rq, + struct drm_printer *m) +{ + unsigned long flags; + + spin_lock_irqsave(&engine->sched_engine->lock, flags); + + intel_engine_dump_active_requests(&engine->sched_engine->requests, hung_rq, m); + + drm_printf(m, "\tOn hold?: %lu\n", + list_count(&engine->sched_engine->hold)); + + spin_unlock_irqrestore(&engine->sched_engine->lock, flags); +} + #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) #include "selftest_execlists.c" #endif diff --git a/sys/dev/pci/drm/i915/gt/intel_execlists_submission.h b/sys/dev/pci/drm/i915/gt/intel_execlists_submission.h index a1aa92c983a..d2c7d45ea06 100644 --- a/sys/dev/pci/drm/i915/gt/intel_execlists_submission.h +++ b/sys/dev/pci/drm/i915/gt/intel_execlists_submission.h @@ -32,6 +32,10 @@ void intel_execlists_show_requests(struct intel_engine_cs *engine, int indent), unsigned int max); +void intel_execlists_dump_active_requests(struct intel_engine_cs *engine, + struct i915_request *hung_rq, + struct drm_printer *m); + bool intel_engine_in_execlists_submission_mode(const struct intel_engine_cs *engine); diff --git a/sys/dev/pci/drm/i915/i915_gpu_error.c b/sys/dev/pci/drm/i915/i915_gpu_error.c index 0dbc91c37ef..b11a4dfea5b 100644 --- a/sys/dev/pci/drm/i915/i915_gpu_error.c +++ b/sys/dev/pci/drm/i915/i915_gpu_error.c @@ -1643,35 +1643,15 @@ capture_engine(struct intel_engine_cs *engine, { struct intel_engine_capture_vma *capture = NULL; struct intel_engine_coredump *ee; - struct intel_context *ce; + struct intel_context *ce = NULL; struct i915_request *rq = NULL; - unsigned long flags; ee = intel_engine_coredump_alloc(engine, ALLOW_FAIL, dump_flags); if (!ee) return NULL; - ce = intel_engine_get_hung_context(engine); - if (ce) { - intel_engine_clear_hung_context(engine); - rq = intel_context_get_active_request(ce); - if (!rq || !i915_request_started(rq)) - goto no_request_capture; - } else { - /* - * Getting here with GuC enabled means it is a forced error capture - * with no actual hang. So, no need to attempt the execlist search. - */ - if (!intel_uc_uses_guc_submission(&engine->gt->uc)) { - spin_lock_irqsave(&engine->sched_engine->lock, flags); - rq = intel_engine_execlist_find_hung_request(engine); - if (rq) - rq = i915_request_get_rcu(rq); - spin_unlock_irqrestore(&engine->sched_engine->lock, - flags); - } - } - if (!rq) + intel_engine_get_hung_entity(engine, &ce, &rq); + if (!rq || !i915_request_started(rq)) goto no_request_capture; capture = intel_engine_coredump_add_request(ee, rq, ATOMIC_MAYFAIL); -- 2.20.1