[PATCH 3/3] drm/i915: Trace point callbacks for validation

[daniele.ceraolospurio@intel.com]

From: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>

These callbacks can be assigned to specific functions inside an external
validation kernel module. This module can then extract run-time
information to make sure everything is working as expected.

Specifically, these two callbacks extract information about full PPGTT
and batch dispatch.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
---
 drivers/gpu/drm/i915/i915_gem_context.c    |  3 +++
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |  3 +++
 drivers/gpu/drm/i915/i915_trace.h          | 22 ++++++++++++++++++++++
 3 files changed, 28 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 99f7022..120a319 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -90,6 +90,9 @@
 #include "i915_drv.h"
 #include "i915_trace.h"
 
+i915_ppgtt_validation_callback_t ppgtt_validation_callback = NULL;
+EXPORT_SYMBOL_GPL(ppgtt_validation_callback);
+
 /* This is a HW constraint. The value below is the largest known requirement
  * I've seen in a spec to date, and that was a workaround for a non-shipping
  * part. It should be safe to decrease this, but it's more future proof as is.
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 0b2b76e..7feb977 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -33,6 +33,9 @@
 #include "intel_drv.h"
 #include <linux/dma_remapping.h>
 
+i915_gem_ring_dispatch_callback_t i915_gem_ring_dispatch_validation_callback = NULL;
+EXPORT_SYMBOL_GPL(i915_gem_ring_dispatch_validation_callback);
+
 #define  __EXEC_OBJECT_HAS_PIN (1<<31)
 #define  __EXEC_OBJECT_HAS_FENCE (1<<30)
 #define  __EXEC_OBJECT_NEEDS_BIAS (1<<28)
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index 4e73e3a..98c6f47 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -15,6 +15,18 @@
 #define TRACE_SYSTEM_STRING __stringify(TRACE_SYSTEM)
 #define TRACE_INCLUDE_FILE i915_trace
 
+/* validation callbacks */
+
+typedef void (*i915_ppgtt_validation_callback_t)(unsigned int action_code,
+						 struct i915_hw_ppgtt *ppgtt);
+extern i915_ppgtt_validation_callback_t ppgtt_validation_callback;
+
+typedef void (*i915_gem_ring_dispatch_callback_t)(struct intel_engine_cs *ring,
+						  u32 seqno,
+						  u32 flags,
+						  struct intel_context *ctx);
+extern i915_gem_ring_dispatch_callback_t i915_gem_ring_dispatch_validation_callback;
+
 /* pipe updates */
 
 TRACE_EVENT(i915_pipe_update_start,
@@ -371,6 +383,10 @@ TRACE_EVENT(i915_gem_ring_dispatch,
 			   __entry->flags = flags;
 			   __entry->vm = ctx->vm;
 			   i915_trace_irq_get(ring, seqno);
+
+			   if (i915_gem_ring_dispatch_validation_callback)
+				   i915_gem_ring_dispatch_validation_callback(ring,
+						      seqno, flags, ctx);
 			   ),
 
 	    TP_printk("dev=%u, ring=%u, seqno=%u, flags=%x, vm=%p",
@@ -607,6 +623,9 @@ TRACE_EVENT(create_vm_for_ctx,
 			__entry->vm = &ppgtt->base;
 			__entry->dev = ppgtt->base.dev->primary->index;
 			__entry->pid = (unsigned int)task_pid_nr(current);
+
+			if (ppgtt_validation_callback)
+				ppgtt_validation_callback(0, ppgtt);
 	),
 
 	TP_printk("dev=%u, task_pid=%u, vm=%p",
@@ -627,6 +646,9 @@ TRACE_EVENT(ppgtt_release,
 	TP_fast_assign(
 		__entry->vm = &ppgtt->base;
 		__entry->dev = ppgtt->base.dev->primary->index;
+
+		if (ppgtt_validation_callback)
+			ppgtt_validation_callback(1, ppgtt);
 	),
 
 	TP_printk("dev=%u, vm=%p", __entry->dev, __entry->vm)
-- 
1.8.5.2