[PATCH 4/6] drm/i915/gem: Split eb_vma into its own allocation
Chris Wilson
chris at chris-wilson.co.uk
Fri Mar 13 11:52:52 UTC 2020
Use a separate array allocation for the execbuf vma, so that we can
track their lifetime independently from the copy of the user arguments.
With luck, this has a secondary benefit of splitting the malloc size to
within reason and avoid vmalloc.
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
.../gpu/drm/i915/gem/i915_gem_execbuffer.c | 59 +++++++++++++++----
1 file changed, 48 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index d3f4f28e9468..2729c143c051 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -40,6 +40,37 @@ struct eb_vma {
u32 handle;
};
+struct eb_vma_array {
+ struct kref kref;
+ struct eb_vma vma[];
+};
+
+static struct eb_vma_array *eb_vma_array_create(unsigned int count)
+{
+ struct eb_vma_array *arr;
+
+ arr = kvmalloc(struct_size(arr, vma, count), GFP_KERNEL | __GFP_NOWARN);
+ if (!arr)
+ return NULL;
+
+ kref_init(&arr->kref);
+ arr->vma[0].vma = NULL;
+
+ return arr;
+}
+
+static void eb_vma_array_destroy(struct kref *kref)
+{
+ struct eb_vma_array *arr = container_of(kref, typeof(*arr), kref);
+
+ kvfree(arr);
+}
+
+static void eb_vma_array_put(struct eb_vma_array *arr)
+{
+ kref_put(&arr->kref, eb_vma_array_destroy);
+}
+
enum {
FORCE_CPU_RELOC = 1,
FORCE_GTT_RELOC,
@@ -283,6 +314,7 @@ struct i915_execbuffer {
*/
int lut_size;
struct hlist_head *buckets; /** ht for relocation handles */
+ struct eb_vma_array *array;
};
static inline bool eb_use_cmdparser(const struct i915_execbuffer *eb)
@@ -294,6 +326,13 @@ static inline bool eb_use_cmdparser(const struct i915_execbuffer *eb)
static int eb_create(struct i915_execbuffer *eb)
{
+ /* Allocate an extra slot for use by the command parser */
+ eb->array = eb_vma_array_create(eb->buffer_count + 1);
+ if (!eb->array)
+ return -ENOMEM;
+
+ eb->vma = eb->array->vma;
+
if (!(eb->args->flags & I915_EXEC_HANDLE_LUT)) {
unsigned int size = 1 + ilog2(eb->buffer_count);
@@ -327,8 +366,10 @@ static int eb_create(struct i915_execbuffer *eb)
break;
} while (--size);
- if (unlikely(!size))
+ if (unlikely(!size)) {
+ eb_vma_array_put(eb->array);
return -ENOMEM;
+ }
eb->lut_size = size;
} else {
@@ -794,6 +835,7 @@ static int eb_lookup_vmas(struct i915_execbuffer *eb)
eb_add_vma(eb, i, batch, vma);
}
+ eb->vma[i].vma = NULL;
return 0;
err_obj:
@@ -835,8 +877,6 @@ static void eb_release_vmas(const struct i915_execbuffer *eb)
if (!vma)
break;
- eb->vma[i].vma = NULL;
-
if (ev->flags & __EXEC_OBJECT_HAS_PIN)
__eb_unreserve_vma(vma, ev->flags);
@@ -848,6 +888,8 @@ static void eb_destroy(const struct i915_execbuffer *eb)
{
GEM_BUG_ON(eb->reloc_cache.rq);
+ eb_vma_array_put(eb->array);
+
if (eb->lut_size > 0)
kfree(eb->buckets);
}
@@ -1600,8 +1642,6 @@ static int eb_move_to_gpu(struct i915_execbuffer *eb)
__eb_unreserve_vma(vma, flags);
i915_vma_put(vma);
-
- ev->vma = NULL;
}
ww_acquire_fini(&acquire);
@@ -2386,8 +2426,6 @@ i915_gem_do_execbuffer(struct drm_device *dev,
args->flags |= __EXEC_HAS_RELOC;
eb.exec = exec;
- eb.vma = (struct eb_vma *)(exec + args->buffer_count + 1);
- eb.vma[0].vma = NULL;
eb.invalid_flags = __EXEC_OBJECT_UNKNOWN_FLAGS;
reloc_cache_init(&eb.reloc_cache, eb.i915);
@@ -2615,7 +2653,7 @@ i915_gem_do_execbuffer(struct drm_device *dev,
static size_t eb_element_size(void)
{
- return sizeof(struct drm_i915_gem_exec_object2) + sizeof(struct eb_vma);
+ return sizeof(struct drm_i915_gem_exec_object2);
}
static bool check_buffer_count(size_t count)
@@ -2671,7 +2709,7 @@ i915_gem_execbuffer_ioctl(struct drm_device *dev, void *data,
/* Copy in the exec list from userland */
exec_list = kvmalloc_array(count, sizeof(*exec_list),
__GFP_NOWARN | GFP_KERNEL);
- exec2_list = kvmalloc_array(count + 1, eb_element_size(),
+ exec2_list = kvmalloc_array(count, eb_element_size(),
__GFP_NOWARN | GFP_KERNEL);
if (exec_list == NULL || exec2_list == NULL) {
drm_dbg(&i915->drm,
@@ -2749,8 +2787,7 @@ i915_gem_execbuffer2_ioctl(struct drm_device *dev, void *data,
if (err)
return err;
- /* Allocate an extra slot for use by the command parser */
- exec2_list = kvmalloc_array(count + 1, eb_element_size(),
+ exec2_list = kvmalloc_array(count, eb_element_size(),
__GFP_NOWARN | GFP_KERNEL);
if (exec2_list == NULL) {
drm_dbg(&i915->drm, "Failed to allocate exec list for %zd buffers\n",
--
2.20.1
More information about the Intel-gfx-trybot
mailing list