[PATCH v6 25/34] drm/i915: Added debugfs interface to scheduler tuning parameters

John.C.Harrison
2016-04-20T17:14:26Z

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>
---
drivers/gpu/drm/i915/i915_debugfs.c | 187 ++++++++++++++++++++++++++++++++++++
1 file changed, 187 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index e89781a..980bb20 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},