Commit da7ac715 authored by Tvrtko Ursulin's avatar Tvrtko Ursulin Committed by Chris Wilson
Browse files

drm/i915: Show timeline dependencies for debug 



Include the signalers each request in the timeline is waiting on, as a
means to try and identify the cause of a stall. This can be quite
verbose, even as for now we only show each request in the timeline and
its immediate antecedents.

This generates output like:

Timeline 886: { count 1, ready: 0, inflight: 0, seqno: { current: 664, last: 666 }, engine: rcs0 }
  U 886:29a-  prio=0 @ 134ms: gem_exec_parall<4621>
    U bc1:27a-  prio=0 @ 134ms: gem_exec_parall[4917]
Timeline 825: { count 1, ready: 0, inflight: 0, seqno: { current: 802, last: 804 }, engine: vcs0 }
  U 825:324  prio=0 @ 107ms: gem_exec_parall<4518>
    U b75:140-  prio=0 @ 110ms: gem_exec_parall<5486>
Timeline b46: { count 1, ready: 0, inflight: 0, seqno: { current: 782, last: 784 }, engine: vcs0 }
  U b46:310-  prio=0 @ 70ms: gem_exec_parall<5428>
    U c11:170-  prio=0 @ 70ms: gem_exec_parall[5501]
Timeline 96b: { count 1, ready: 0, inflight: 0, seqno: { current: 632, last: 634 }, engine: vcs0 }
  U 96b:27a-  prio=0 @ 67ms: gem_exec_parall<4878>
    U b75:19e-  prio=0 @ 67ms: gem_exec_parall<5486>

Signed-off-by: default avatarTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20201119165616.10834-6-chris@chris-wilson.co.uk
parent b5b349b9

drivers/gpu/drm/i915/i915_debugfs.c

+2 −1
Original line number Diff line number Diff line
@@ -45,6 +45,7 @@ 
#include "i915_debugfs.h"

#include "i915_debugfs_params.h"

#include "i915_irq.h"

#include "i915_scheduler.h"

#include "i915_trace.h"

#include "intel_pm.h"

#include "intel_sideband.h"
@@ -1323,7 +1324,7 @@ static int i915_engine_info(struct seq_file *m, void *unused) 
	for_each_uabi_engine(engine, i915)

		intel_engine_dump(engine, &p, "%s\n", engine->name);



	intel_gt_show_timelines(&i915->gt, &p, NULL);

	intel_gt_show_timelines(&i915->gt, &p, i915_request_show_with_schedule);



	intel_runtime_pm_put(&i915->runtime_pm, wakeref);

drivers/gpu/drm/i915/i915_scheduler.c

+28 −0
Original line number Diff line number Diff line
@@ -504,6 +504,34 @@ void i915_sched_node_fini(struct i915_sched_node *node) 
	spin_unlock_irq(&schedule_lock);

}



void i915_request_show_with_schedule(struct drm_printer *m,

				     const struct i915_request *rq,

				     const char *prefix,

				     int indent)

{

	struct i915_dependency *dep;



	i915_request_show(m, rq, prefix, indent);

	if (i915_request_completed(rq))

		return;



	rcu_read_lock();

	for_each_signaler(dep, rq) {

		const struct i915_request *signaler =

			node_to_request(dep->signaler);



		/* Dependencies along the same timeline are expected. */

		if (signaler->timeline == rq->timeline)

			continue;



		if (i915_request_completed(signaler))

			continue;



		i915_request_show(m, signaler, prefix, indent + 2);

	}

	rcu_read_unlock();

}



static void i915_global_scheduler_shrink(void)

{

	kmem_cache_shrink(global.slab_dependencies);

drivers/gpu/drm/i915/i915_scheduler.h

+7 −0
Original line number Diff line number Diff line
@@ -13,6 +13,8 @@ 


#include "i915_scheduler_types.h"



struct drm_printer;



#define priolist_for_each_request(it, plist, idx) \

	for (idx = 0; idx < ARRAY_SIZE((plist)->requests); idx++) \

		list_for_each_entry(it, &(plist)->requests[idx], sched.link)
@@ -54,4 +56,9 @@ static inline void i915_priolist_free(struct i915_priolist *p) 
		__i915_priolist_free(p);

}



void i915_request_show_with_schedule(struct drm_printer *m,

				     const struct i915_request *rq,

				     const char *prefix,

				     int indent);



#endif /* _I915_SCHEDULER_H_ */