[PATCH v3 27/28] drm/i915: Add unique id to the request structure for debugging

John.C.Harrison
2014-11-24T18:50:35Z

For debugging purposes, it is useful to be able to uniquely identify a given
request structure as it works its way through the system. This becomes
especially tricky once the seqno value is lazily allocated as then the request
has nothing but its pointer to identify it for much of its life.

For: VIZ-4377
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Thomas Daniel <Thomas.Daniel@intel.com>
---
drivers/gpu/drm/i915/i915_drv.h | 4 ++++
drivers/gpu/drm/i915/intel_lrc.c | 2 ++
drivers/gpu/drm/i915/intel_ringbuffer.c | 2 ++
3 files changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index cf9fc74..20ff643 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1787,6 +1787,8 @@ struct drm_i915_private {
void (*stop_ring)(struct intel_engine_cs *ring);
} gt;

+ uint32_t request_uniq;
+
/*
* NOTE: This is the dri1/ums dungeon, don't add stuff here. Your patch
* will be rejected. Instead look for a better place.
@@ -2030,6 +2032,8 @@ struct drm_i915_gem_request {
/** deferred free list for dereferencing from IRQ context */
struct list_head delay_free_list;
uint32_t delay_free_count;
+
+ uint32_t uniq;
};

void i915_gem_request_free(struct kref *req_ref);
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index a7d4b50..f82fc1a 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -880,6 +880,7 @@ static int logical_ring_alloc_request(struct intel_engine_cs *ring,
struct intel_context *ctx)
{
struct drm_i915_gem_request *request;
+ struct drm_i915_private *dev_private = ring->dev->dev_private;
int ret;

if (ring->outstanding_lazy_request)
@@ -899,6 +900,7 @@ static int logical_ring_alloc_request(struct intel_engine_cs *ring,

kref_init(&request->ref);
request->ring = ring;
+ request->uniq = dev_private->request_uniq++;

ret = i915_gem_get_seqno(ring->dev, &request->seqno);
if (ret) {
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index a62ac336..afc8974 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -2037,6 +2037,7 @@ intel_ring_alloc_request(struct intel_engine_cs *ring)
{
int ret;
struct drm_i915_gem_request *request;
+ struct drm_i915_private *dev_private = ring->dev->dev_private;

if (ring->outstanding_lazy_request)
return 0;
@@ -2047,6 +2048,7 @@ intel_ring_alloc_request(struct intel_engine_cs *ring)

kref_init(&request->ref);
request->ring = ring;
+ request->uniq = dev_private->request_uniq++;

ret = i915_gem_get_seqno(ring->dev, &request->seqno);
if (ret) {