[PATCH v6 3/8] drm/i915: Fix up locking around dumping requests lists
John.C.Harrison at Intel.com
John.C.Harrison at Intel.com
Fri Jan 27 00:28:37 UTC 2023
From: John Harrison <John.C.Harrison at Intel.com>
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. In order to do that, also move the report of hold
count (which is an execlist only concept) from the top level dump
function to the lower level execlist specific function. Also, move the
execlist specific code into the execlist source file.
v2: Rename some functions and move to more appropriate files (Daniele).
v3: Rename new execlist dump function (Daniele)
Fixes: dc0dad365c5e ("drm/i915/guc: Fix for error capture after full GPU reset with GuC")
Signed-off-by: John Harrison <John.C.Harrison at Intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Acked-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Cc: Matthew Brost <matthew.brost at intel.com>
Cc: Jani Nikula <jani.nikula at linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: Matt Roper <matthew.d.roper at intel.com>
Cc: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
Cc: Michael Cheng <michael.cheng at intel.com>
Cc: Lucas De Marchi <lucas.demarchi at intel.com>
Cc: Bruce Chang <yu.bruce.chang at intel.com>
Cc: Alan Previn <alan.previn.teres.alexis at intel.com>
Cc: Matthew Auld <matthew.auld at intel.com>
---
drivers/gpu/drm/i915/gt/intel_engine.h | 4 +-
drivers/gpu/drm/i915/gt/intel_engine_cs.c | 74 +++++++++----------
.../drm/i915/gt/intel_execlists_submission.c | 27 +++++++
.../drm/i915/gt/intel_execlists_submission.h | 4 +
drivers/gpu/drm/i915/i915_gpu_error.c | 26 +------
5 files changed, 73 insertions(+), 62 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine.h b/drivers/gpu/drm/i915/gt/intel_engine.h
index 0e24af5efee9c..b58c30ac8ef02 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine.h
@@ -250,8 +250,8 @@ 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/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index a86bdbee7a6be..9f703f255d721 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -2114,17 +2114,6 @@ 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);
@@ -2216,11 +2205,11 @@ 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.
@@ -2229,29 +2218,20 @@ 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);
}
@@ -2263,7 +2243,6 @@ 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) {
@@ -2300,13 +2279,8 @@ 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) {
@@ -2352,8 +2326,7 @@ 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;
@@ -2405,6 +2378,33 @@ 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/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
index 18ffe55282e59..3c573d41d4046 100644
--- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
+++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c
@@ -4150,6 +4150,33 @@ 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/drivers/gpu/drm/i915/gt/intel_execlists_submission.h b/drivers/gpu/drm/i915/gt/intel_execlists_submission.h
index a1aa92c983a51..d2c7d45ea0623 100644
--- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.h
+++ b/drivers/gpu/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/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 9e2d17785a9a8..b20bd6365615b 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -1596,35 +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);
- 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);
--
2.39.1
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