From: Ankitprasad Sharma <ankitprasad.r.sharma@xxxxxxxxx>
When constructing a batchbuffer, it is sometimes crucial to know the
largest hole into which we can fit a fenceable buffer (for example when
handling very large objects on gen2 and gen3). This depends on the
fragmentation of pinned buffers inside the aperture, a question only the
kernel can easily answer.
This patch extends the current DRM_I915_GEM_GET_APERTURE ioctl to
include a couple of new fields in its reply to userspace - the total
amount of space available in the mappable region of the aperture and
also the single largest block available.
This is not quite what userspace wants to answer the question of whether
this batch will fit as fences are also required to meet severe alignment
constraints within the batch. For this purpose, a third conservative
estimate of largest fence available is also provided. For when userspace
needs more than one batch, we also provide the cumulative space
available for fences such that it has some additional guidance to how
much space it could allocate to fences. Conservatism still wins.
This patch extends the GET_APERTURE ioctl to add support
for getting total size and available size of the stolen region as
well as single largest block available in the stolen region too.
The patch also adds a debugfs file for convenient testing and
reporting.
v2: The first object cannot end at offset 0, so we can use last==0 to
detect the empty list.
v3: Expand all values to 64bit, just in case.
Report total mappable aperture size for userspace that cannot easily
determine it by inspecting the PCI device.
v4: (Rodrigo) Fixed rebase conflicts.
v5: Rebased to the latest drm-intel-nightly (Ankit)
v6: Keeping limits to get_aperture ioctl, and moved changing numbers to
debugfs, Addressed comments (Chris/Tvrtko)
v7: Squashed stolen memory size patch to this one, Added a new version
field to validate the map_size and stolen size values, Changed Author
to me (Ankit) due to significant changes in the logic used to get size
values
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Signed-off-by: Ankitprasad Sharma <ankitprasad.r.sharma@xxxxxxxxx>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
---
drivers/gpu/drm/i915/i915_debugfs.c | 143 +++++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/i915_drv.h | 3 +
drivers/gpu/drm/i915/i915_gem.c | 4 +
drivers/gpu/drm/i915/i915_gem_stolen.c | 27 +++++++
include/uapi/drm/i915_drm.h | 17 ++++
5 files changed, 194 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index e5b4274..c052174 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -586,6 +586,148 @@ static int i915_gem_object_info(struct seq_file *m, void* data)
return 0;
}
+static int vma_rank_by_ggtt(void *priv,
+ struct list_head *A,
+ struct list_head *B)
+{
+ struct i915_vma *a = list_entry(A, typeof(*a), exec_list);
+ struct i915_vma *b = list_entry(B, typeof(*b), exec_list);
+
+ return a->node.start - b->node.start;
+}
+
+static u32 __fence_size(struct drm_i915_private *dev_priv, u32 start, u32 end)
+{
+ u32 size = end - start;
+ u32 fence_size;
+
+ if (INTEL_INFO(dev_priv)->gen < 4) {
+ u32 fence_max;
+ u32 fence_next;
+
+ if (IS_GEN3(dev_priv)) {
+ fence_max = I830_FENCE_MAX_SIZE_VAL << 20;
+ fence_next = 1024*1024;
+ } else {
+ fence_max = I830_FENCE_MAX_SIZE_VAL << 19;
+ fence_next = 512*1024;
+ }
+
+ fence_max = min(fence_max, size);
+ fence_size = 0;
+ /* Find fence_size less than fence_max and power of 2 */
+ while (fence_next <= fence_max) {
+ u32 base = ALIGN(start, fence_next);
+ if (base + fence_next > end)
+ break;
+
+ fence_size = fence_next;
+ fence_next <<= 1;
+ }
+ } else {
+ fence_size = size;
+ }
+
+ return fence_size;
+}
+
+static int i915_gem_aperture_info(struct seq_file *m, void *data)
+{
+ struct drm_info_node *node = m->private;
+ struct drm_device *dev = node->minor->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct i915_ggtt *ggtt = &dev_priv->ggtt;
+ struct drm_i915_gem_get_aperture arg;
+ struct i915_vma *vma;
+ struct list_head map_list;
+ const uint64_t map_limit = ggtt->mappable_end;
+ uint64_t map_space, map_largest, fence_space, fence_largest;
+ uint64_t last, hole_size, stolen_free, stolen_largest;
+ int ret;
+
+ INIT_LIST_HEAD(&map_list);
+
+ map_space = map_largest = 0;
+ fence_space = fence_largest = 0;
+
+ ret = i915_gem_get_aperture_ioctl(node->minor->dev, &arg, NULL);
+ if (ret)
+ return ret;
+
+ mutex_lock(&dev->struct_mutex);
+
+ i915_gem_stolen_size_info(dev_priv, &stolen_free,
+ &stolen_largest);
+
+ list_for_each_entry(vma, &ggtt->base.active_list, vm_link)
+ if (vma->pin_count &&
+ (vma->node.start + vma->node.size) <= map_limit)
+ list_add(&vma->exec_list, &map_list);
+ list_for_each_entry(vma, &ggtt->base.inactive_list, vm_link)
+ if (vma->pin_count &&
+ (vma->node.start + vma->node.size) <= map_limit)
+ list_add(&vma->exec_list, &map_list);
+
+ last = 0;
+ list_sort(NULL, &map_list, vma_rank_by_ggtt);
+ while (!list_empty(&map_list)) {
+ vma = list_first_entry(&map_list, typeof(*vma), exec_list);
+ list_del_init(&vma->exec_list);
+
+ if (last == 0)
+ goto skip_first;
+
+ hole_size = vma->node.start - last;
+ if (hole_size > map_largest)
+ map_largest = hole_size;
+ map_space += hole_size;
+
+ hole_size = __fence_size(dev_priv, last, vma->node.start);
+ if (hole_size > fence_largest)
+ fence_largest = hole_size;
+ fence_space += hole_size;
+
+skip_first:
+ last = vma->node.start + vma->node.size;
+ }
+ if (last < map_limit) {
+ hole_size = map_limit - last;
+ if (hole_size > map_largest)
+ map_largest = hole_size;
+ map_space += hole_size;
+
+ hole_size = __fence_size(dev_priv, last, map_limit);
+ if (hole_size > fence_largest)
+ fence_largest = hole_size;
+ fence_space += hole_size;
+ }
+
+ mutex_unlock(&dev->struct_mutex);
+
+ seq_printf(m, "Total size of the GTT: %llu bytes\n",
+ arg.aper_size);
+ seq_printf(m, "Available space in the GTT: %llu bytes\n",
+ arg.aper_available_size);
+ seq_printf(m, "Total space in the mappable aperture: %llu bytes\n",
+ arg.map_total_size);
+ seq_printf(m, "Available space in the mappable aperture: %llu bytes\n",
+ map_space);
+ seq_printf(m, "Single largest space in the mappable aperture: %llu bytes\n",
+ map_largest);
+ seq_printf(m, "Available space for fences: %llu bytes\n",
+ fence_space);
+ seq_printf(m, "Single largest fence available: %llu bytes\n",
+ fence_largest);
+ seq_printf(m, "Total size of the stolen region: %llu bytes\n",
+ arg.stolen_total_size);
+ seq_printf(m, "Available size of the stolen region: %llu bytes\n",
+ stolen_free);
+ seq_printf(m, "Single largest area in the stolen region: %llu bytes\n",
+ stolen_largest);
+
+ return 0;
+}
+
static int i915_gem_gtt_info(struct seq_file *m, void *data)
{
struct drm_info_node *node = m->private;
@@ -5406,6 +5548,7 @@ static int i915_debugfs_create(struct dentry *root,
static const struct drm_info_list i915_debugfs_list[] = {
{"i915_capabilities", i915_capabilities, 0},
{"i915_gem_objects", i915_gem_object_info, 0},
+ {"i915_gem_aperture", i915_gem_aperture_info, 0},
{"i915_gem_gtt", i915_gem_gtt_info, 0},
{"i915_gem_pinned", i915_gem_gtt_info, 0, (void *) PINNED_LIST},
{"i915_gem_active", i915_gem_object_list_info, 0, (void *) ACTIVE_LIST},
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index aac4b5b..0ceb699 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3564,6 +3564,9 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
u32 gtt_offset,
u32 size);
int __must_check i915_gem_stolen_freeze(struct drm_i915_private *i915);
+void i915_gem_stolen_size_info(struct drm_i915_private *dev_priv,
+ uint64_t *stolen_free,
+ uint64_t *stolen_largest);
/* i915_gem_shrinker.c */
unsigned long i915_gem_shrink(struct drm_i915_private *dev_priv,
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index ba2d482..d8d81e3 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -165,6 +165,10 @@ i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
args->aper_size = ggtt->base.total;
args->aper_available_size = args->aper_size - pinned;
+ args->version = 1;
+ args->map_total_size = ggtt->mappable_end;
+ args->stolen_total_size =
+ dev_priv->mm.volatile_stolen ? 0 : ggtt->stolen_usable_size;
return 0;
}
diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 0e6203c..1fb4597 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -914,3 +914,30 @@ int i915_gem_stolen_freeze(struct drm_i915_private *i915)
return ret;
}
+
+
+void i915_gem_stolen_size_info(struct drm_i915_private *dev_priv,
+ uint64_t *stolen_free,
+ uint64_t *stolen_largest)
+{
+ struct drm_mm *mm = &dev_priv->mm.stolen;
+ struct drm_mm_node *hole;
+ uint64_t hole_size, hole_start, hole_end, largest_hole = 0;
+ uint64_t total_free = 0;
+
+ if (dev_priv->mm.volatile_stolen) {
+ *stolen_free = 0;
+ *stolen_largest = 0;
+ return;
+ }
+
+ drm_mm_for_each_hole(hole, mm, hole_start, hole_end) {
+ hole_size = hole_end - hole_start;
+ total_free += hole_size;
+ if (largest_hole < hole_size)
+ largest_hole = hole_size;
+ }
+
+ *stolen_free = total_free;
+ *stolen_largest = largest_hole;
+}
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index ceff4c1..bc16f0a 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -1011,6 +1011,23 @@ struct drm_i915_gem_get_aperture {
* bytes
*/
__u64 aper_available_size;
+
+ /**
+ * Versioning to indicate if map_total_size and stolen_total_size
+ * value returned are valid or not
+ */
+ __u64 version;
+
+ /**
+ * Total space in the mappable region of the aperture, in bytes
+ */
+ __u64 map_total_size;
+
+ /**
+ * Total space in the stolen region, in bytes
+ */
+ __u64 stolen_total_size;
+
};
struct drm_i915_get_pipe_from_crtc_id {
--
1.9.1
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