[Intel-gfx] [PATCH 11/15] drm/i915: debugfs entries for scheduler params

[Ben Widawsky]

Using the i915 client list we can easily read and set the various
parameters.

Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_debugfs.c |  138 +++++++++++++++++++++++++++++++++++
 1 files changed, 138 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 59b9f22..790875d 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1543,6 +1543,136 @@ static const struct file_operations i915_cache_sharing_fops = {
 	.llseek = default_llseek,
 };
 
+static ssize_t
+i915_sched_read(struct file *filp,
+		char __user *ubuf,
+		size_t max,
+		loff_t *ppos)
+{
+	struct drm_device *dev = filp->private_data;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_i915_file_private *temp;
+	unsigned high, low;
+	size_t len = 0;
+	char *buf, *buf2;
+	struct {
+		pid_t pid;
+		int outstanding;
+		int forced;
+		int high;
+		int low;
+	} requests[20];
+	int entries, entry_size, i = 0, ret = 0;
+
+	if (!i915_scheduler)
+		return 0;
+
+	ret = mutex_lock_interruptible(&dev->struct_mutex);
+	if (ret)
+		return ret;
+
+	high = dev_priv->scheduler.high_watermark;
+	low = dev_priv->scheduler.low_watermark;
+	list_for_each_entry(temp, &dev_priv->i915_client_list, client_link) {
+		struct drm_file *file = temp->drm_file;
+		requests[i].pid = file->pid;
+		spin_lock(&temp->lock);
+		requests[i].outstanding = temp->outstanding_requests;
+		requests[i].forced = temp->forced_throttles;
+		spin_unlock(&temp->lock);
+		i++;
+	}
+	mutex_unlock(&dev->struct_mutex);
+
+	entries = i;
+
+	entry_size = strlen("pid 123456 = XXXX outstanding (XXXXXX forced)\n") + 1;
+	buf2 = drm_malloc_ab(entries, entry_size);
+	memset(buf2, 0, entries * entry_size);
+	for(i = 0; i < entries; i++) {
+		len += sprintf(buf2 + len,
+			       "pid %06d = %06d outstanding (%06d forced)\n",
+				requests[i].pid, requests[i].outstanding,
+				requests[i].forced);
+	}
+
+	buf = kasprintf(GFP_KERNEL, "%s\n"
+				    "Scheduler = %s\n"
+				    "High watermark = %d buffers\n"
+				    "Low watermark = %d buffers\n",
+				     buf2, "fair", high, low);
+
+	len = strlen(buf);
+
+	ret = simple_read_from_buffer(ubuf, max, ppos, buf, len);
+
+	drm_free_large(buf2);
+	kfree(buf);
+	return ret;
+}
+
+static ssize_t
+i915_sched_write(struct file *filp,
+		 const char __user *ubuf,
+		 size_t cnt,
+		 loff_t *ppos)
+{
+	struct drm_device *dev = filp->private_data;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	char *buf, *ptr;
+	uint32_t high, low;
+	int ret;
+
+	buf = drm_malloc_ab(cnt + 1, 1);
+	if (!buf)
+		return -E2BIG;
+
+	ret = copy_from_user(buf, ubuf, cnt);
+	if (ret)
+		goto out;
+
+	ret = mutex_lock_interruptible(&dev->struct_mutex);
+	if (ret)
+		return ret;
+
+	low = dev_priv->scheduler.low_watermark;
+	high = dev_priv->scheduler.high_watermark;
+
+	buf[cnt] = 0;
+	ptr = buf;
+
+	while ((ptr != NULL) && *ptr != 0) {
+		if (!strncmp(ptr, "high=", 5))
+			high = simple_strtoul(ptr + 5, NULL, 0);
+		if (!strncmp(ptr, "low=", 4))
+			low = simple_strtoul(ptr + 4, NULL, 0);
+		ptr = strchr(ptr, ',');
+		if (ptr != NULL)
+			ptr += strspn(ptr, ", \t\n");
+	}
+
+	if (high != dev_priv->scheduler.high_watermark ||
+	    low != dev_priv->scheduler.low_watermark) {
+		DRM_INFO("new high = %d\n", high);
+		DRM_INFO("new low = %d\n", low);
+		dev_priv->scheduler.high_watermark = high;
+		dev_priv->scheduler.low_watermark = low;
+	}
+
+	mutex_unlock(&dev->struct_mutex);
+out:
+	drm_free_large(buf);
+	return cnt;
+}
+
+static const struct file_operations i915_scheduler_fops = {
+	.owner = THIS_MODULE,
+	.open = i915_debugfs_common_open,
+	.read = i915_sched_read,
+	.write = i915_sched_write,
+};
+
+
 /* As the drm_debugfs_init() routines are called before dev->dev_private is
  * allocated we need to hook into the minor for release. */
 static int
@@ -1712,6 +1842,12 @@ int i915_debugfs_init(struct drm_minor *minor)
 	if (ret)
 		return ret;
 
+	ret = i915_debugfs_create(minor->debugfs_root, minor,
+				  "i915_scheduler",
+				  &i915_scheduler_fops);
+	if (ret)
+		return ret;
+
 	return drm_debugfs_create_files(i915_debugfs_list,
 					I915_DEBUGFS_ENTRIES,
 					minor->debugfs_root, minor);
@@ -1729,6 +1865,8 @@ void i915_debugfs_cleanup(struct drm_minor *minor)
 				 1, minor);
 	drm_debugfs_remove_files((struct drm_info_list *) &i915_cache_sharing_fops,
 				 1, minor);
+	drm_debugfs_remove_files((struct drm_info_list *) &i915_scheduler_fops,
+				 1, minor);
 }
 
 #endif /* CONFIG_DEBUG_FS */
-- 
1.7.7.3