On 1/18/2023 10:49 PM, John.C.Harrison@xxxxxxxxx wrote:
From: John Harrison <John.C.Harrison@xxxxxxxxx>
The debugfs dump of requests was confused about what state requires
the execlist lock versus the GuC lock. There was also a bunch of
duplicated messy code between it and the error capture code.
So refactor the hung request search into a re-usable function. And
reduce the span of the execlist state lock to only the execlist
specific code paths.
Signed-off-by: John Harrison <John.C.Harrison@xxxxxxxxx>
---
drivers/gpu/drm/i915/gt/intel_context.c | 29 +++++++++++++
drivers/gpu/drm/i915/gt/intel_context.h | 3 ++
drivers/gpu/drm/i915/gt/intel_engine_cs.c | 51 +++++++++++------------
drivers/gpu/drm/i915/i915_gpu_error.c | 27 ++----------
4 files changed, 60 insertions(+), 50 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
index e7c5509c48ef1..a61f052092ed9 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.c
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -559,6 +559,35 @@ struct i915_request *intel_context_find_active_request(struct intel_context *ce)
return active;
}
+void intel_get_hung_entity(struct intel_engine_cs *engine,
+ struct intel_context **ce, struct i915_request **rq)
IMO this belongs in the engine_cs.c file, given that the engine is the
input. Might also be worth renaming to intel_engine_*
+{
+ unsigned long flags;
+
+ *ce = intel_engine_get_hung_context(engine);
+ if (*ce) {
+ intel_engine_clear_hung_context(engine);
+
+ /* This will reference count the request (if found) */
+ *rq = intel_context_find_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 = intel_engine_execlist_find_hung_request(engine);
+ if (*rq)
+ *rq = i915_request_get_rcu(*rq);
+ spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
+}
+
void intel_context_bind_parent_child(struct intel_context *parent,
struct intel_context *child)
{
diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915/gt/intel_context.h
index fb62b7b8cbcda..ca50f3312a941 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.h
+++ b/drivers/gpu/drm/i915/gt/intel_context.h
@@ -271,6 +271,9 @@ struct i915_request *intel_context_create_request(struct intel_context *ce);
struct i915_request *
intel_context_find_active_request(struct intel_context *ce);
+void intel_get_hung_entity(struct intel_engine_cs *engine,
+ struct intel_context **ce, struct i915_request **rq);
+
static inline bool intel_context_is_barrier(const struct intel_context *ce)
{
return test_bit(CONTEXT_BARRIER_BIT, &ce->flags);
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 6a082658d0082..5e173dfc8849e 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -2216,11 +2216,27 @@ 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 execlist_dump_active_requests(struct intel_engine_cs *engine,
Might be worth moving this to the execlists submission file, to be
symmetrical with the GuC submission one. Other execlists functions are
in this file though, so not a blocker.
+ 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);
+}
+
+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.
@@ -2229,31 +2245,20 @@ 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_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) {
- /* This will reference count the request (if found) */
- hung_rq = intel_context_find_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);
+ execlist_dump_active_requests(engine, hung_rq, m);
+
if (hung_rq)
i915_request_put(hung_rq);
}
@@ -2265,7 +2270,6 @@ 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) {
@@ -2302,13 +2306,8 @@ 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));
This print moves from the global function to the execlists submission
one. AFAICS this is only used in execlists mode so not an issue, but a
note in the commit message would've been nice.
- 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) {
diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 7ea36478ee52d..78cf95e4dd230 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -1596,36 +1596,15 @@ 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);
- /* This will reference count the request (if found) */
- rq = intel_context_find_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_get_hung_entity(engine, &ce, &rq);
+ if (!rq || !i915_request_started(rq))
goto no_request_capture;
This has been a pain to review, but AFAICS all the locking is correct,
so with the get_hung function moved to the intel_engine file this is:
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx>
capture = intel_engine_coredump_add_request(ee, rq, ATOMIC_MAYFAIL);
