drm/i915: Added debugfs interface to scheduler tuning parameters

There are various parameters within the scheduler which can be tuned
to improve performance, reduce memory footprint, etc. This change adds
support for altering these via debugfs.

v2: Updated for priorities now being signed values.

v5: Squashed priority bumping entries into this patch rather than a
separate patch all of their own.

v6: Updated to newer nightly (lots of ring -> engine renaming).

Updated to use 'to_i915()' instead of dev_private. [review feedback
from Joonas Lahtinen]

Added an admin only check when setting the parameters to prevent rogue
user code trying to break the system with strange settings. [review
feedback from Jesse Barnes]

For: VIZ-1587
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 187 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index e89781a611fb..980bb20ed28a 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -39,6 +39,7 @@
 #include "intel_ringbuffer.h"
 #include <drm/i915_drm.h>
 #include "i915_drv.h"
+#include "i915_scheduler.h"
 
 enum {
 	ACTIVE_LIST,
@@ -1125,6 +1126,186 @@ DEFINE_SIMPLE_ATTRIBUTE(i915_next_seqno_fops,
 			i915_next_seqno_get, i915_next_seqno_set,
 			"0x%llx\n");
 
+static int
+i915_scheduler_priority_min_get(void *data, u64 *val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	*val = (u64) scheduler->priority_level_min;
+	return 0;
+}
+
+static int
+i915_scheduler_priority_min_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	scheduler->priority_level_min = (int32_t) val;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_scheduler_priority_min_fops,
+			i915_scheduler_priority_min_get,
+			i915_scheduler_priority_min_set,
+			"%lld\n");
+
+static int
+i915_scheduler_priority_max_get(void *data, u64 *val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	*val = (u64) scheduler->priority_level_max;
+	return 0;
+}
+
+static int
+i915_scheduler_priority_max_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	scheduler->priority_level_max = (int32_t) val;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_scheduler_priority_max_fops,
+			i915_scheduler_priority_max_get,
+			i915_scheduler_priority_max_set,
+			"%lld\n");
+
+static int
+i915_scheduler_priority_bump_get(void *data, u64 *val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	*val = (u64) scheduler->priority_level_bump;
+	return 0;
+}
+
+static int
+i915_scheduler_priority_bump_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	scheduler->priority_level_bump = (u32) val;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_scheduler_priority_bump_fops,
+			i915_scheduler_priority_bump_get,
+			i915_scheduler_priority_bump_set,
+			"%lld\n");
+
+static int
+i915_scheduler_priority_preempt_get(void *data, u64 *val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	*val = (u64) scheduler->priority_level_preempt;
+	return 0;
+}
+
+static int
+i915_scheduler_priority_preempt_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	scheduler->priority_level_preempt = (u32) val;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_scheduler_priority_preempt_fops,
+			i915_scheduler_priority_preempt_get,
+			i915_scheduler_priority_preempt_set,
+			"%lld\n");
+
+static int
+i915_scheduler_min_flying_get(void *data, u64 *val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	*val = (u64) scheduler->min_flying;
+	return 0;
+}
+
+static int
+i915_scheduler_min_flying_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	scheduler->min_flying = (u32) val;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_scheduler_min_flying_fops,
+			i915_scheduler_min_flying_get,
+			i915_scheduler_min_flying_set,
+			"%llu\n");
+
+static int
+i915_scheduler_file_queue_max_get(void *data, u64 *val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	*val = (u64) scheduler->file_queue_max;
+	return 0;
+}
+
+static int
+i915_scheduler_file_queue_max_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct i915_scheduler *scheduler = dev_priv->scheduler;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	scheduler->file_queue_max = (u32) val;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_scheduler_file_queue_max_fops,
+			i915_scheduler_file_queue_max_get,
+			i915_scheduler_file_queue_max_set,
+			"%llu\n");
+
 static int i915_frequency_info(struct seq_file *m, void *unused)
 {
 	struct drm_info_node *node = m->private;
@@ -5426,6 +5607,12 @@ static const struct i915_debugfs_files {
 	{"i915_gem_drop_caches", &i915_drop_caches_fops},
 	{"i915_error_state", &i915_error_state_fops},
 	{"i915_next_seqno", &i915_next_seqno_fops},
+	{"i915_scheduler_priority_min", &i915_scheduler_priority_min_fops},
+	{"i915_scheduler_priority_max", &i915_scheduler_priority_max_fops},
+	{"i915_scheduler_priority_bump", &i915_scheduler_priority_bump_fops},
+	{"i915_scheduler_priority_preempt", &i915_scheduler_priority_preempt_fops},
+	{"i915_scheduler_min_flying", &i915_scheduler_min_flying_fops},
+	{"i915_scheduler_file_queue_max", &i915_scheduler_file_queue_max_fops},
 	{"i915_display_crc_ctl", &i915_display_crc_ctl_fops},
 	{"i915_pri_wm_latency", &i915_pri_wm_latency_fops},
 	{"i915_spr_wm_latency", &i915_spr_wm_latency_fops},