[RFC 26/39] drm/i915: Added immediate submission override to scheduler

John.C.Harrison
2015-07-17T14:34:22Z

To aid with debugging issues related to the scheduler, it can be useful to
ensure that all batch buffers are submitted immediately rather than queued until
later. This change adds an override flag via the module parameter to force
instant submission.

Change-Id: I7652df53e2d3c3d77d78bebcf99856e2c53f2801
For: VIZ-1587
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
---
drivers/gpu/drm/i915/i915_scheduler.c | 7 +++++--
drivers/gpu/drm/i915/i915_scheduler.h | 1 +
2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_scheduler.c b/drivers/gpu/drm/i915/i915_scheduler.c
index 224c8b4..c7139f8 100644
--- a/drivers/gpu/drm/i915/i915_scheduler.c
+++ b/drivers/gpu/drm/i915/i915_scheduler.c
@@ -238,8 +238,11 @@ int i915_scheduler_queue_execbuffer(struct i915_scheduler_queue_entry *qe)

list_add_tail(&node->link, &scheduler->node_queue[ring->id]);

- not_flying = i915_scheduler_count_flying(scheduler, ring) <
- scheduler->min_flying;
+ if (i915.scheduler_override & i915_so_submit_on_queue)
+ not_flying = true;
+ else
+ not_flying = i915_scheduler_count_flying(scheduler, ring) <
+ scheduler->min_flying;

spin_unlock_irqrestore(&scheduler->lock, flags);

diff --git a/drivers/gpu/drm/i915/i915_scheduler.h b/drivers/gpu/drm/i915/i915_scheduler.h
index 7d743c9..ce94b0b 100644
--- a/drivers/gpu/drm/i915/i915_scheduler.h
+++ b/drivers/gpu/drm/i915/i915_scheduler.h
@@ -92,6 +92,7 @@ enum {
/* Options for 'scheduler_override' module parameter: */
enum {
i915_so_direct_submit = (1 << 0),
+ i915_so_submit_on_queue = (1 << 1),
};

bool i915_scheduler_is_enabled(struct drm_device *dev);