Previously, the maximum size of a state that could be allocated from a
state pool was a block. However, this has caused us various issues
particularly with shaders which are potentially very large. We've also
hit issues with render passes with a large number of attachments when we
go to allocate the block of surface state. This effectively removes the
restriction on the maximum size of a single state. (There's still a
limit of 1MB imposed by a fixed-length bucket array.)
For states larger than the block size, we just grab a large block off of
the block pool rather than sub-allocating. When we go to allocate some
chunk of state and the current bucket does not have state, we try to
pull a chunk from some larger bucket and split it up. This should
improve memory usage if a client occasionally allocates a large block of
state.
This commit is inspired by some similar work done by Juan A. Suarez
Romero <jasua...@igalia.com>.
---
src/intel/vulkan/anv_allocator.c | 43 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
diff --git a/src/intel/vulkan/anv_allocator.c b/src/intel/vulkan/anv_allocator.c
index 7a687b7..68c389c 100644
--- a/src/intel/vulkan/anv_allocator.c
+++ b/src/intel/vulkan/anv_allocator.c
@@ -650,6 +650,12 @@ anv_fixed_size_state_pool_alloc_new(struct
anv_fixed_size_state_pool *pool,
struct anv_block_state block, old, new;
uint32_t offset;
+ /* If our state is large, we don't need any sub-allocation from a block.
+ * Instead, we just grab whole (potentially large) blocks.
+ */
+ if (state_size >= block_size)
+ return anv_block_pool_alloc(block_pool, state_size);
+
restart:
block.u64 = __sync_fetch_and_add(&pool->block.u64, state_size);
@@ -702,6 +708,43 @@ anv_state_pool_alloc_no_vg(struct anv_state_pool *pool,
goto done;
}
+ /* Try to grab a chunk from some larger bucket and split it up */
+ for (unsigned b = bucket + 1; b < ANV_STATE_BUCKETS; b++) {
+ int32_t chunk_offset;
+ if (anv_free_list_pop(&pool->buckets[b].free_list,
+ &pool->block_pool.map, &chunk_offset)) {
+ unsigned chunk_size = anv_state_pool_get_bucket_size(b);
+
+ if (chunk_size > pool->block_size &&
+ state.alloc_size < pool->block_size) {
+ assert(chunk_size % pool->block_size == 0);
+ /* We don't want to split giant chunks into tiny chunks. Instead,
+ * break anything bigger than a block into block-sized chunks and
+ * then break it down into bucket-sized chunks from there. Return
+ * all but the first block of the chunk to the block bucket.
+ */
+ const uint32_t block_bucket =
+ anv_state_pool_get_bucket(pool->block_size);
+ anv_free_list_push(&pool->buckets[block_bucket].free_list,
+ pool->block_pool.map,
+ chunk_offset + pool->block_size,
+ pool->block_size,
+ (chunk_size / pool->block_size) - 1);
+ chunk_size = pool->block_size;
+ }
+
+ assert(chunk_size % state.alloc_size == 0);
+ anv_free_list_push(&pool->buckets[bucket].free_list,
+ pool->block_pool.map,
+ chunk_offset + state.alloc_size,
+ state.alloc_size,
+ (chunk_size / state.alloc_size) - 1);
+
+ state.offset = chunk_offset;
+ goto done;
+ }
+ }
+
state.offset = anv_fixed_size_state_pool_alloc_new(&pool->buckets[bucket],
&pool->block_pool,
state.alloc_size,
--
2.5.0.400.gff86faf
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