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-rw-r--r--llama.cpp/ggml/src/ggml-alloc.c1249
1 files changed, 1249 insertions, 0 deletions
diff --git a/llama.cpp/ggml/src/ggml-alloc.c b/llama.cpp/ggml/src/ggml-alloc.c
new file mode 100644
index 0000000..41419b6
--- /dev/null
+++ b/llama.cpp/ggml/src/ggml-alloc.c
@@ -0,0 +1,1249 @@
+#include "ggml-alloc.h"
+#include "ggml-backend-impl.h"
+#include "ggml.h"
+#include "ggml-impl.h"
+#include <assert.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define MAX_FREE_BLOCKS 256
+
+//#define GGML_ALLOCATOR_DEBUG
+
+//#define AT_PRINTF(...) GGML_LOG_DEBUG(__VA_ARGS__)
+#define AT_PRINTF(...)
+
+
+static bool ggml_is_view(const struct ggml_tensor * t) {
+ return t->view_src != NULL;
+}
+
+// ops that return true for this function must not use restrict pointers for their backend implementations
+bool ggml_op_can_inplace(enum ggml_op op) {
+ switch (op) {
+ case GGML_OP_FILL:
+ case GGML_OP_SCALE:
+ case GGML_OP_DIAG_MASK_ZERO:
+ case GGML_OP_DIAG_MASK_INF:
+ case GGML_OP_ADD:
+ case GGML_OP_ADD_ID:
+ case GGML_OP_ADD1:
+ case GGML_OP_SUB:
+ case GGML_OP_MUL:
+ case GGML_OP_DIV:
+ case GGML_OP_SQR:
+ case GGML_OP_SQRT:
+ case GGML_OP_LOG:
+ case GGML_OP_UNARY:
+ case GGML_OP_ROPE:
+ case GGML_OP_ROPE_BACK:
+ case GGML_OP_SILU_BACK:
+ case GGML_OP_RMS_NORM:
+ case GGML_OP_RMS_NORM_BACK:
+ case GGML_OP_SOFT_MAX:
+ case GGML_OP_SOFT_MAX_BACK:
+ return true;
+
+ default:
+ return false;
+ }
+}
+
+static size_t aligned_offset(const void * buffer, size_t offset, size_t alignment) {
+ assert(alignment && !(alignment & (alignment - 1))); // power of 2
+ size_t align = (alignment - (((uintptr_t)buffer + offset) % alignment)) % alignment;
+ return offset + align;
+}
+
+// tallocr
+
+struct ggml_tallocr ggml_tallocr_new(ggml_backend_buffer_t buffer) {
+ void * base = ggml_backend_buffer_get_base(buffer);
+ size_t align = ggml_backend_buffer_get_alignment(buffer);
+
+ assert(align && !(align & (align - 1))); // power of 2
+
+ struct ggml_tallocr talloc = (struct ggml_tallocr) {
+ /*.buffer = */ buffer,
+ /*.base = */ base,
+ /*.alignment = */ align,
+ /*.offset = */ aligned_offset(base, 0, align),
+ };
+ return talloc;
+}
+
+enum ggml_status ggml_tallocr_alloc(struct ggml_tallocr * talloc, struct ggml_tensor * tensor) {
+ size_t size = ggml_backend_buffer_get_alloc_size(talloc->buffer, tensor);
+ size = GGML_PAD(size, talloc->alignment);
+
+ if (talloc->offset + size > ggml_backend_buffer_get_size(talloc->buffer)) {
+ GGML_LOG_ERROR("%s: not enough space in the buffer to allocate %s (needed %zu, available %zu)\n",
+ __func__, tensor->name, size, ggml_backend_buffer_get_size(talloc->buffer) - talloc->offset);
+ GGML_ABORT("not enough space in the buffer");
+ }
+
+ void * addr = (char *)ggml_backend_buffer_get_base(talloc->buffer) + talloc->offset;
+ talloc->offset += size;
+
+ assert(((uintptr_t)addr % talloc->alignment) == 0);
+
+ return ggml_backend_tensor_alloc(talloc->buffer, tensor, addr);
+}
+
+// dynamic tensor allocator
+
+#define GGML_VBUFFER_MAX_CHUNKS 16
+
+// relative memory address within an allocation that can be split into multiple buffers (chunks)
+struct buffer_address {
+ int chunk; // index of a backend buffer
+ size_t offset; // local memory offset within the buffer
+};
+
+static const struct buffer_address GGML_BUFFER_ADDRESS_INVALID = { -1, SIZE_MAX };
+
+static bool ggml_buffer_address_less(struct buffer_address a, struct buffer_address b) {
+ return a.chunk != b.chunk ? a.chunk < b.chunk : a.offset < b.offset;
+}
+
+struct free_block {
+ size_t offset;
+ size_t size;
+};
+
+struct tallocr_chunk {
+ struct free_block free_blocks[MAX_FREE_BLOCKS];
+ int n_free_blocks;
+ size_t max_size;
+};
+
+struct ggml_dyn_tallocr {
+ size_t alignment;
+ size_t max_chunk_size;
+ struct tallocr_chunk * chunks[GGML_VBUFFER_MAX_CHUNKS];
+ int n_chunks;
+
+#ifdef GGML_ALLOCATOR_DEBUG
+ struct {
+ const struct ggml_tensor * tensor;
+ struct buffer_address addr;
+ } allocated_tensors[1024];
+#endif
+};
+
+static void ggml_dyn_tallocr_insert_block(struct tallocr_chunk * chunk, size_t offset, size_t size) {
+ GGML_ASSERT(chunk->n_free_blocks < MAX_FREE_BLOCKS && "out of free blocks");
+ // insert the new block in the correct position to keep the array sorted by address (to make merging blocks faster)
+ int insert_pos = 0;
+ while (insert_pos < chunk->n_free_blocks && chunk->free_blocks[insert_pos].offset < offset) {
+ insert_pos++;
+ }
+ // shift all blocks from insert_pos onward to make room for the new block
+ for (int i = chunk->n_free_blocks; i > insert_pos; i--) {
+ chunk->free_blocks[i] = chunk->free_blocks[i-1];
+ }
+ // insert the new block
+ chunk->free_blocks[insert_pos].offset = offset;
+ chunk->free_blocks[insert_pos].size = size;
+ chunk->n_free_blocks++;
+}
+
+static void ggml_dyn_tallocr_remove_block(struct tallocr_chunk * chunk, int idx) {
+ // shift all elements after idx by 1 to the left, overwriting the element at idx
+ for (int i = idx; i < chunk->n_free_blocks; i++) {
+ chunk->free_blocks[i] = chunk->free_blocks[i+1];
+ }
+ chunk->n_free_blocks--;
+}
+
+static int ggml_dyn_tallocr_new_chunk(struct ggml_dyn_tallocr * alloc, size_t min_size) {
+ if (alloc->n_chunks >= GGML_VBUFFER_MAX_CHUNKS) {
+ return -1;
+ }
+ struct tallocr_chunk * chunk = calloc(1, sizeof(struct tallocr_chunk));
+ chunk->n_free_blocks = 1;
+ chunk->free_blocks[0].offset = 0;
+ // available space in a chunk is limited to max_chunk_size, but can be higher if:
+ // 1. a single tensor exceeds the maximum, and cannot fit any other way
+ // 2. we are running out of chunks
+ // backends will either manage to allocate the larger size, or report an error.
+ chunk->free_blocks[0].size = MAX(min_size, alloc->max_chunk_size);
+ if (alloc->n_chunks == GGML_VBUFFER_MAX_CHUNKS - 1) {
+ chunk->free_blocks[0].size = SIZE_MAX/2;
+ }
+ alloc->chunks[alloc->n_chunks] = chunk;
+ alloc->n_chunks++;
+ return alloc->n_chunks - 1;
+}
+
+#ifdef GGML_ALLOCATOR_DEBUG
+static void add_allocated_tensor(struct ggml_dyn_tallocr * alloc, struct buffer_address addr, const struct ggml_tensor * tensor) {
+ for (int i = 0; i < 1024; i++) {
+ if (alloc->allocated_tensors[i].tensor == NULL) {
+ alloc->allocated_tensors[i].tensor = tensor;
+ alloc->allocated_tensors[i].addr = addr;
+ return;
+ }
+ }
+ GGML_ABORT("out of allocated_tensors");
+}
+static void remove_allocated_tensor(struct ggml_dyn_tallocr * alloc, struct buffer_address addr, const struct ggml_tensor * tensor) {
+ for (int i = 0; i < 1024; i++) {
+ if (alloc->allocated_tensors[i].addr.chunk == addr.chunk && alloc->allocated_tensors[i].addr.offset == addr.offset) {
+ alloc->allocated_tensors[i].tensor = NULL;
+ return;
+ }
+ }
+ GGML_ABORT("tried to free tensor %s not found\n", tensor->name);
+}
+#endif
+
+static struct buffer_address ggml_dyn_tallocr_alloc(struct ggml_dyn_tallocr * alloc, size_t size, const struct ggml_tensor * tensor) {
+ size = aligned_offset(NULL, size, alloc->alignment);
+
+ AT_PRINTF("%s: allocating %s (%zu bytes) - ", __func__, tensor->name, size);
+
+ int best_fit_chunk = -1;
+ int best_fit_block = -1;
+ size_t max_avail = 0;
+
+ // find the best fitting free block besides the last block, within any chunk
+ for (int c = 0; c < alloc->n_chunks; ++c) {
+ struct tallocr_chunk * chunk = alloc->chunks[c];
+ size_t best_fit_size = SIZE_MAX;
+ for (int i = 0; i < chunk->n_free_blocks - 1; i++) {
+ struct free_block * block = &chunk->free_blocks[i];
+ max_avail = MAX(max_avail, block->size);
+ if (block->size >= size && block->size <= best_fit_size) {
+ best_fit_chunk = c;
+ best_fit_block = i;
+ best_fit_size = block->size;
+ }
+ }
+ }
+
+ if (best_fit_block == -1) {
+ // no suitable block found, try the last block (this may grow a chunks size)
+ int64_t best_reuse = INT64_MIN;
+ for (int c = 0; c < alloc->n_chunks; ++c) {
+ struct tallocr_chunk * chunk = alloc->chunks[c];
+ if (chunk->n_free_blocks > 0) {
+ struct free_block * block = &chunk->free_blocks[chunk->n_free_blocks - 1];
+ max_avail = MAX(max_avail, block->size);
+ int64_t reuse_factor = chunk->max_size - block->offset - size;
+ // reuse_factor < 0 : amount of extra memory that needs to be allocated
+ // reuse_factor = 0 : allocated free space exactly matches tensor size
+ // reuse_factor > 0 : superfluous memory that will remain unused
+ bool better_reuse = best_reuse < 0 && reuse_factor > best_reuse;
+ bool better_fit = reuse_factor >= 0 && reuse_factor < best_reuse;
+ if (block->size >= size && (better_reuse || better_fit)) {
+ best_fit_chunk = c;
+ best_fit_block = chunk->n_free_blocks - 1;
+ best_reuse = reuse_factor;
+ }
+ }
+ }
+ }
+
+ if (best_fit_block == -1) {
+ // none of the existing chunks have enough space left
+ best_fit_chunk = ggml_dyn_tallocr_new_chunk(alloc, size);
+ best_fit_block = 0;
+ }
+ if (best_fit_chunk == -1) {
+ // since the last chunk always has virtually endless memory, this should never happen
+ GGML_LOG_ERROR("%s: not enough space in the buffer to allocate %zu bytes, largest block available %zu bytes\n",
+ __func__, size, max_avail);
+ GGML_ABORT("graph allocation: failed to reserve memory");
+ }
+
+ struct tallocr_chunk * chunk = alloc->chunks[best_fit_chunk];
+ struct free_block * block = &chunk->free_blocks[best_fit_block];
+ struct buffer_address addr = {.chunk = best_fit_chunk, .offset = block->offset };
+ block->offset += size;
+ block->size -= size;
+ if (block->size == 0) {
+ // remove block if empty
+ ggml_dyn_tallocr_remove_block(chunk, best_fit_block);
+ }
+
+ AT_PRINTF("block %d, offset %zu, chunk %d\n", best_fit_block, addr.offset, addr.chunk);
+
+#ifdef GGML_ALLOCATOR_DEBUG
+ add_allocated_tensor(alloc, addr, tensor);
+ size_t cur_max = addr.offset + size;
+ if (cur_max > chunk->max_size) {
+ // sort allocated_tensors by chunk/offset
+ for (int i = 0; i < 1024; i++) {
+ for (int j = i + 1; j < 1024; j++) {
+ if (ggml_buffer_address_less(alloc->allocated_tensors[j].addr, alloc->allocated_tensors[i].addr)) {
+ const struct ggml_tensor * tmp_tensor = alloc->allocated_tensors[i].tensor;
+ struct buffer_address tmp_addr = alloc->allocated_tensors[i].addr;
+ alloc->allocated_tensors[i].tensor = alloc->allocated_tensors[j].tensor;
+ alloc->allocated_tensors[i].addr = alloc->allocated_tensors[j].addr;
+ alloc->allocated_tensors[j].tensor = tmp_tensor;
+ alloc->allocated_tensors[j].addr = tmp_addr;
+ }
+ }
+ }
+ GGML_LOG_DEBUG("max_size[%d] = %.2f MB: tensors: ", addr.chunk, cur_max / 1024.0 / 1024.0);
+ for (int i = 0; i < 1024; i++) {
+ if (alloc->allocated_tensors[i].tensor) {
+ GGML_LOG_DEBUG("%s [%d: %zx-%zx] (%.2f MB) ", alloc->allocated_tensors[i].tensor->name,
+ alloc->allocated_tensors[i].addr.chunk,
+ alloc->allocated_tensors[i].addr.offset,
+ alloc->allocated_tensors[i].addr.offset + ggml_nbytes(alloc->allocated_tensors[i].tensor),
+ ggml_nbytes(alloc->allocated_tensors[i].tensor) / 1024.0 / 1024.0);
+ }
+ }
+ GGML_LOG_DEBUG("\n");
+ }
+#endif
+
+ chunk->max_size = MAX(chunk->max_size, addr.offset + size);
+
+ return addr;
+
+ GGML_UNUSED(tensor);
+}
+
+// this is a very naive implementation, but for our case the number of free blocks should be very small
+static void ggml_dyn_tallocr_free_bytes(struct ggml_dyn_tallocr * alloc, struct buffer_address addr, size_t size) {
+ size = aligned_offset(NULL, size, alloc->alignment);
+
+ struct tallocr_chunk * chunk = alloc->chunks[addr.chunk];
+
+ // see if we can merge with an existing block
+ for (int i = 0; i < chunk->n_free_blocks; i++) {
+ struct free_block * block = &chunk->free_blocks[i];
+ // check if ptr is at the end of the block
+ if (block->offset + block->size == addr.offset) {
+ block->size += size;
+ // check if we can merge with the next block
+ if (i < chunk->n_free_blocks - 1) {
+ struct free_block * next = &chunk->free_blocks[i+1];
+ if (block->offset + block->size == next->offset) {
+ block->size += next->size;
+ ggml_dyn_tallocr_remove_block(chunk, i+1);
+ }
+ }
+ return;
+ }
+ // check if ptr is at the beginning of the block
+ if (addr.offset + size == block->offset) {
+ block->offset = addr.offset;
+ block->size += size;
+ // check if we can merge with the previous block
+ if (i > 0) {
+ struct free_block * prev = &chunk->free_blocks[i-1];
+ if (prev->offset + prev->size == block->offset) {
+ prev->size += block->size;
+ ggml_dyn_tallocr_remove_block(chunk, i);
+ }
+ }
+ return;
+ }
+ }
+ // otherwise, add a new block
+ ggml_dyn_tallocr_insert_block(chunk, addr.offset, size);
+}
+
+static void ggml_dyn_tallocr_reset(struct ggml_dyn_tallocr * alloc) {
+ for (int i = 0; i < GGML_VBUFFER_MAX_CHUNKS; i++) {
+ free(alloc->chunks[i]);
+ alloc->chunks[i] = NULL;
+ }
+ alloc->n_chunks = 0;
+
+#ifdef GGML_ALLOCATOR_DEBUG
+ for (int i = 0; i < 1024; i++) {
+ alloc->allocated_tensors[i].tensor = NULL;
+ }
+#endif
+}
+
+static struct ggml_dyn_tallocr * ggml_dyn_tallocr_new(size_t alignment, size_t max_buffer_size) {
+ struct ggml_dyn_tallocr * alloc = (struct ggml_dyn_tallocr *)malloc(sizeof(struct ggml_dyn_tallocr));
+
+ *alloc = (struct ggml_dyn_tallocr) {
+ /*.alignment = */ alignment,
+ /*.max_chunk_size = */ MIN(max_buffer_size, SIZE_MAX/2), // clamp to avoid overflows
+ /*.chunks = */ {NULL},
+ /*.n_chunks = */ 0,
+#ifdef GGML_ALLOCATOR_DEBUG
+ /*.allocated_tensors = */ {{0}},
+#endif
+ };
+
+ ggml_dyn_tallocr_reset(alloc);
+
+ return alloc;
+}
+
+static void ggml_dyn_tallocr_free(struct ggml_dyn_tallocr * alloc) {
+ for (int i = 0; i < alloc->n_chunks; ++i) {
+ free(alloc->chunks[i]);
+ }
+ free(alloc);
+}
+
+static size_t ggml_dyn_tallocr_max_size(struct ggml_dyn_tallocr * alloc, int chunk) {
+ return chunk < alloc->n_chunks ? alloc->chunks[chunk]->max_size : 0;
+}
+
+
+// virtual buffer with contiguous memory range, split into multiple backend buffers (chunks)
+
+struct vbuffer {
+ ggml_backend_buffer_t chunks[GGML_VBUFFER_MAX_CHUNKS];
+};
+
+static void ggml_vbuffer_free(struct vbuffer * buf) {
+ if (buf == NULL) {
+ return;
+ }
+ for (int i = 0; i < GGML_VBUFFER_MAX_CHUNKS; ++i) {
+ ggml_backend_buffer_free(buf->chunks[i]);
+ }
+ free(buf);
+}
+
+static size_t ggml_vbuffer_chunk_size(struct vbuffer * buf, int chunk) {
+ return buf->chunks[chunk] ? ggml_backend_buffer_get_size(buf->chunks[chunk]) : 0;
+}
+
+static size_t ggml_vbuffer_size(struct vbuffer * buf) {
+ size_t size = 0;
+ for (int i = 0; i < GGML_VBUFFER_MAX_CHUNKS && buf->chunks[i]; ++i) {
+ size += ggml_backend_buffer_get_size(buf->chunks[i]);
+ }
+ return size;
+}
+
+static struct vbuffer * ggml_vbuffer_alloc(ggml_backend_buffer_type_t buft, const struct ggml_dyn_tallocr * talloc, enum ggml_backend_buffer_usage usage) {
+ struct vbuffer * buf = (struct vbuffer *)calloc(1, sizeof(struct vbuffer));
+ if (buf == NULL) {
+ return NULL;
+ }
+
+ for (int n = 0; n < talloc->n_chunks; n++) {
+ size_t chunk_size = talloc->chunks[n]->max_size;
+ buf->chunks[n] = ggml_backend_buft_alloc_buffer(buft, chunk_size);
+ if (buf->chunks[n] == NULL) {
+ ggml_vbuffer_free(buf);
+ return NULL;
+ }
+ ggml_backend_buffer_set_usage(buf->chunks[n], usage);
+ }
+ return buf;
+}
+
+static void ggml_vbuffer_tensor_alloc(struct vbuffer * buf, struct ggml_tensor * tensor, struct buffer_address buf_addr) {
+ void * base = ggml_backend_buffer_get_base(buf->chunks[buf_addr.chunk]);
+ void * addr = (char *)base + buf_addr.offset;
+ ggml_backend_tensor_alloc(buf->chunks[buf_addr.chunk], tensor, addr);
+}
+
+static void ggml_vbuffer_reset(struct vbuffer * buf) {
+ for (int i = 0; i < GGML_VBUFFER_MAX_CHUNKS && buf->chunks[i]; ++i) {
+ ggml_backend_buffer_reset(buf->chunks[i]);
+ }
+}
+
+
+/////////////////////////////////////
+
+// graph allocator
+
+struct hash_node {
+ int n_children;
+ int n_views;
+ int buffer_id;
+ struct buffer_address addr;
+ bool allocated;
+};
+
+struct tensor_alloc {
+ int buffer_id;
+ struct buffer_address addr;
+ size_t size_max; // 0 = pre-allocated, unused, or view
+};
+
+struct leaf_alloc {
+ struct tensor_alloc leaf;
+};
+
+struct node_alloc {
+ struct tensor_alloc dst;
+ struct tensor_alloc src[GGML_MAX_SRC];
+};
+
+struct ggml_gallocr {
+ ggml_backend_buffer_type_t * bufts; // [n_buffers]
+ struct vbuffer ** buffers; // [n_buffers]
+ struct ggml_dyn_tallocr ** buf_tallocs; // [n_buffers]
+ int n_buffers;
+
+ struct ggml_hash_set hash_set;
+ struct hash_node * hash_values; // [hash_set.size]
+
+ struct node_alloc * node_allocs; // [n_nodes]
+ int n_nodes;
+
+ struct leaf_alloc * leaf_allocs; // [n_leafs]
+ int n_leafs;
+};
+
+ggml_gallocr_t ggml_gallocr_new_n(ggml_backend_buffer_type_t * bufts, int n_bufs) {
+ ggml_gallocr_t galloc = (ggml_gallocr_t)calloc(1, sizeof(struct ggml_gallocr));
+ GGML_ASSERT(galloc != NULL);
+
+ galloc->bufts = calloc(n_bufs, sizeof(ggml_backend_buffer_type_t));
+ GGML_ASSERT(galloc->bufts != NULL);
+
+ galloc->buffers = calloc(n_bufs, sizeof(struct vbuffer *));
+ GGML_ASSERT(galloc->buffers != NULL);
+
+ galloc->buf_tallocs = calloc(n_bufs, sizeof(struct ggml_dyn_tallocr *));
+ GGML_ASSERT(galloc->buf_tallocs != NULL);
+
+ for (int i = 0; i < n_bufs; i++) {
+ galloc->bufts[i] = bufts[i];
+ galloc->buffers[i] = NULL;
+
+ // check if the same buffer type is used multiple times and reuse the same allocator
+ for (int j = 0; j < i; j++) {
+ if (bufts[i] == bufts[j]) {
+ galloc->buf_tallocs[i] = galloc->buf_tallocs[j];
+ break;
+ }
+ }
+
+ if (galloc->buf_tallocs[i] == NULL) {
+ size_t alignment = ggml_backend_buft_get_alignment(bufts[i]);
+ size_t max_size = ggml_backend_buft_get_max_size(bufts[i]);
+ galloc->buf_tallocs[i] = ggml_dyn_tallocr_new(alignment, max_size);
+ }
+ }
+ galloc->n_buffers = n_bufs;
+
+ return galloc;
+}
+
+ggml_gallocr_t ggml_gallocr_new(ggml_backend_buffer_type_t buft) {
+ return ggml_gallocr_new_n(&buft, 1);
+}
+
+void ggml_gallocr_free(ggml_gallocr_t galloc) {
+ if (galloc == NULL) {
+ return;
+ }
+
+ for (int i = 0; i < galloc->n_buffers; i++) {
+ if (galloc->buffers != NULL) {
+ // skip if already freed
+ bool freed = false;
+ for (int j = 0; j < i; j++) {
+ if (galloc->buffers[j] == galloc->buffers[i]) {
+ freed = true;
+ break;
+ }
+ }
+ if (!freed) {
+ ggml_vbuffer_free(galloc->buffers[i]);
+ }
+ }
+ if (galloc->buf_tallocs != NULL) {
+ // skip if already freed
+ bool freed = false;
+ for (int j = 0; j < i; j++) {
+ if (galloc->buf_tallocs[j] == galloc->buf_tallocs[i]) {
+ freed = true;
+ break;
+ }
+ }
+ if (!freed) {
+ ggml_dyn_tallocr_free(galloc->buf_tallocs[i]);
+ }
+ }
+ }
+
+ ggml_hash_set_free(&galloc->hash_set);
+ free(galloc->hash_values);
+ free(galloc->bufts);
+ free(galloc->buffers);
+ free(galloc->buf_tallocs);
+ free(galloc->node_allocs);
+ free(galloc->leaf_allocs);
+ free(galloc);
+}
+
+typedef struct ggml_gallocr * ggml_gallocr_t;
+
+static struct hash_node * ggml_gallocr_hash_get(ggml_gallocr_t galloc, struct ggml_tensor * t) {
+ size_t i = ggml_hash_find_or_insert(&galloc->hash_set, t);
+ return &galloc->hash_values[i];
+}
+
+static bool ggml_gallocr_is_own(ggml_gallocr_t galloc, struct ggml_tensor * t) {
+ return ggml_gallocr_hash_get(galloc, t)->allocated;
+}
+
+static bool ggml_gallocr_is_allocated(ggml_gallocr_t galloc, struct ggml_tensor * t) {
+ return t->data != NULL // tensor data already set externally
+ || t->buffer // tensor on external buffer (but not yet allocated)
+ || ggml_gallocr_is_own(galloc, t); // tensor will be allocated by galloc
+}
+
+// free the extra space at the end if the new tensor is smaller
+static void ggml_gallocr_free_extra_space(ggml_gallocr_t galloc, struct ggml_tensor * node, struct ggml_tensor * parent) {
+ struct hash_node * hn = ggml_gallocr_hash_get(galloc, node);
+ struct hash_node * p_hn = ggml_gallocr_hash_get(galloc, parent);
+
+ size_t parent_size = ggml_backend_buft_get_alloc_size(galloc->bufts[p_hn->buffer_id], parent);
+ size_t node_size = ggml_backend_buft_get_alloc_size(galloc->bufts[hn->buffer_id], node);
+
+ GGML_ASSERT(parent_size >= node_size);
+
+ // note: we want after the freeing the chunks to continue to be aligned
+ struct ggml_dyn_tallocr * p_alloc = galloc->buf_tallocs[p_hn->buffer_id];
+ parent_size = aligned_offset(NULL, parent_size, p_alloc->alignment);
+ node_size = aligned_offset(NULL, node_size, p_alloc->alignment);
+
+ if (parent_size > node_size) {
+ struct buffer_address p_addr = p_hn->addr;
+ p_addr.offset += node_size;
+ size_t extra_size = parent_size - node_size;
+ AT_PRINTF("freeing extra %zu bytes from parent %s for %s\n", extra_size, parent->name, node->name);
+ ggml_dyn_tallocr_free_bytes(p_alloc, p_addr, extra_size);
+ }
+}
+
+static void ggml_gallocr_allocate_node(ggml_gallocr_t galloc, struct ggml_tensor * node, int buffer_id) {
+ GGML_ASSERT(buffer_id >= 0);
+ struct hash_node * hn = ggml_gallocr_hash_get(galloc, node);
+
+ if (!ggml_gallocr_is_allocated(galloc, node) && !ggml_is_view(node)) {
+ hn->allocated = true;
+ assert(hn->addr.offset == 0);
+
+ // try to reuse a parent's buffer (inplace)
+ if (ggml_op_can_inplace(node->op)) {
+ for (int i = 0; i < GGML_MAX_SRC; i++) {
+ struct ggml_tensor * parent = node->src[i];
+ if (parent == NULL) {
+ continue;
+ }
+
+ // if the node's data is external, then we cannot re-use it
+ if (!ggml_gallocr_is_own(galloc, parent)) {
+ AT_PRINTF("not reusing parent %s for %s as %p is external\n", parent->name, node->name, parent->data);
+ continue;
+ }
+
+ // outputs cannot be reused
+ if (parent->flags & GGML_TENSOR_FLAG_OUTPUT || (parent->view_src != NULL && parent->view_src->flags & GGML_TENSOR_FLAG_OUTPUT)) {
+ AT_PRINTF("not reusing parent %s for %s as it is an output\n", parent->name, node->name);
+ continue;
+ }
+
+ if (!ggml_are_same_layout(node, parent)) {
+ AT_PRINTF("not reusing parent %s for %s as layouts are different\n", parent->name, node->name);
+ continue;
+ }
+
+ struct hash_node * p_hn = ggml_gallocr_hash_get(galloc, parent);
+ if (p_hn->n_children == 1 && p_hn->n_views == 0) {
+ if (ggml_is_view(parent)) {
+ struct ggml_tensor * view_src = parent->view_src;
+ struct hash_node * view_src_hn = ggml_gallocr_hash_get(galloc, view_src);
+ if (view_src_hn->n_views == 1 && view_src_hn->n_children == 0 && view_src->data == parent->data) {
+ AT_PRINTF("reusing view parent %s (%s) for %s\n", parent->name, view_src->name, node->name);
+ assert(view_src_hn->addr.chunk == p_hn->addr.chunk && view_src_hn->addr.offset == p_hn->addr.offset);
+ hn->buffer_id = p_hn->buffer_id;
+ hn->addr = p_hn->addr;
+ p_hn->allocated = false; // avoid freeing the parent
+ view_src_hn->allocated = false;
+ ggml_gallocr_free_extra_space(galloc, node, view_src);
+ return;
+ }
+ } else {
+ AT_PRINTF("reusing parent %s for %s\n", parent->name, node->name);
+ hn->buffer_id = p_hn->buffer_id;
+ hn->addr = p_hn->addr;
+ p_hn->allocated = false; // avoid freeing the parent
+ ggml_gallocr_free_extra_space(galloc, node, parent);
+ return;
+ }
+ }
+ }
+ }
+ // allocate tensor from the buffer
+ struct ggml_dyn_tallocr * alloc = galloc->buf_tallocs[buffer_id];
+ ggml_backend_buffer_type_t buft = galloc->bufts[buffer_id];
+ size_t size = ggml_backend_buft_get_alloc_size(buft, node);
+ hn->buffer_id = buffer_id;
+ hn->addr = ggml_dyn_tallocr_alloc(alloc, size, node);
+ }
+}
+
+static void ggml_gallocr_free_node(ggml_gallocr_t galloc, struct ggml_tensor * node) {
+ // graph outputs are never freed
+ if (node->flags & GGML_TENSOR_FLAG_OUTPUT) {
+ AT_PRINTF("not freeing output %s\n", node->name);
+ return;
+ }
+
+ struct hash_node * hn = ggml_gallocr_hash_get(galloc, node);
+ int buffer_id = hn->buffer_id;
+ struct ggml_dyn_tallocr * alloc = galloc->buf_tallocs[buffer_id];
+ ggml_backend_buffer_type_t buft = galloc->bufts[buffer_id];
+ size_t size = ggml_backend_buft_get_alloc_size(buft, node);
+
+ AT_PRINTF("%s: freeing %s at {chunk=%d, offset=%zu} (%zu bytes) - n_free_blocks = %d\n",
+ __func__, node->name, hn->addr.chunk, hn->addr.offset, size, alloc->chunks[hn->addr.chunk]->n_free_blocks);
+#ifdef GGML_ALLOCATOR_DEBUG
+ remove_allocated_tensor(alloc, hn->addr, node);
+#endif
+
+ ggml_dyn_tallocr_free_bytes(alloc, hn->addr, size);
+ hn->allocated = false;
+}
+
+static int get_node_buffer_id(const int * node_buffer_ids, int i) {
+ return node_buffer_ids ? node_buffer_ids[i] : 0;
+}
+
+static void ggml_gallocr_alloc_graph_impl(ggml_gallocr_t galloc, struct ggml_cgraph * graph, const int * node_buffer_ids, const int * leaf_buffer_ids) {
+ // clear hash tables
+ ggml_hash_set_reset(&galloc->hash_set);
+ memset(galloc->hash_values, 0, sizeof(struct hash_node) * galloc->hash_set.size);
+
+ // allocate leafs
+ // these may be tensors that the application is not using in the graph, but may still want to allocate for other purposes
+ for (int i = 0; i < graph->n_leafs; i++) {
+ struct ggml_tensor * leaf = graph->leafs[i];
+ ggml_gallocr_allocate_node(galloc, leaf, get_node_buffer_id(leaf_buffer_ids, i));
+ }
+
+ // count number of children and views
+ // allocate other graph inputs and leafs first to avoid overwriting them
+ for (int i = 0; i < graph->n_nodes; i++) {
+ struct ggml_tensor * node = graph->nodes[i];
+
+ // TODO: better way to add external dependencies
+ // GGML_OP_NONE does not appear normally in the graph nodes, but is used by ggml-backend to add dependencies to
+ // control when some tensors are allocated and freed. in this case, the dependencies are in `src`, but the node
+ // itself is never used and should not be considered a dependency
+ if (ggml_is_view(node) && node->op != GGML_OP_NONE) {
+ struct ggml_tensor * view_src = node->view_src;
+ ggml_gallocr_hash_get(galloc, view_src)->n_views += 1;
+ }
+
+ if (node->flags & GGML_TENSOR_FLAG_INPUT) {
+ ggml_gallocr_allocate_node(galloc, graph->nodes[i], get_node_buffer_id(node_buffer_ids, i));
+ }
+
+ for (int j = 0; j < GGML_MAX_SRC; j++) {
+ struct ggml_tensor * src = node->src[j];
+ if (src == NULL) {
+ continue;
+ }
+
+ ggml_gallocr_hash_get(galloc, src)->n_children += 1;
+
+ // allocate explicit inputs
+ if (src->flags & GGML_TENSOR_FLAG_INPUT) {
+ ggml_gallocr_allocate_node(galloc, src, get_node_buffer_id(node_buffer_ids, i));
+ }
+ }
+ }
+
+ // allocate tensors
+ for (int i = 0; i < graph->n_nodes; i++) {
+ struct ggml_tensor * node = graph->nodes[i];
+ int buffer_id = get_node_buffer_id(node_buffer_ids, i);
+
+ // allocate parents (only leafs need to be allocated at this point)
+ for (int j = 0; j < GGML_MAX_SRC; j++) {
+ struct ggml_tensor * parent = node->src[j];
+ if (parent == NULL) {
+ continue;
+ }
+ ggml_gallocr_allocate_node(galloc, parent, buffer_id);
+ }
+
+ // allocate node
+ ggml_gallocr_allocate_node(galloc, node, buffer_id);
+
+ AT_PRINTF("exec: %s (%s) <= ", ggml_op_desc(node), node->name);
+ for (int j = 0; j < GGML_MAX_SRC; j++) {
+ struct ggml_tensor * parent = node->src[j];
+ if (parent == NULL) {
+ continue;
+ }
+ AT_PRINTF("%s", parent->name);
+ if (j < GGML_MAX_SRC - 1 && node->src[j + 1] != NULL) {
+ AT_PRINTF(", ");
+ }
+ }
+ AT_PRINTF("\n");
+
+ // update parents
+ for (int j = 0; j < GGML_MAX_SRC; j++) {
+ struct ggml_tensor * parent = node->src[j];
+ if (parent == NULL) {
+ continue;
+ }
+ struct hash_node * p_hn = ggml_gallocr_hash_get(galloc, parent);
+ p_hn->n_children -= 1;
+
+ AT_PRINTF("parent %s: %d children, %d views, allocated: %d\n",
+ parent->name, p_hn->n_children, p_hn->n_views, p_hn->allocated);
+
+ if (p_hn->n_children == 0 && p_hn->n_views == 0) {
+ if (ggml_is_view(parent)) {
+ struct ggml_tensor * view_src = parent->view_src;
+ struct hash_node * view_src_hn = ggml_gallocr_hash_get(galloc, view_src);
+ view_src_hn->n_views -= 1;
+ AT_PRINTF("view_src %s: %d children, %d views\n",
+ view_src->name, view_src_hn->n_children, view_src_hn->n_views);
+ if (view_src_hn->n_views == 0 && view_src_hn->n_children == 0 && view_src_hn->allocated) {
+ ggml_gallocr_free_node(galloc, view_src);
+ }
+ }
+ else if (p_hn->allocated) {
+ ggml_gallocr_free_node(galloc, parent);
+ }
+ }
+ AT_PRINTF("\n");
+ }
+ }
+}
+
+static bool ggml_gallocr_reserve_n_impl(
+ ggml_gallocr_t galloc, struct ggml_cgraph * graph, const int * node_buffer_ids, const int * leaf_buffer_ids, bool no_alloc) {
+ size_t min_hash_size = graph->n_nodes + graph->n_leafs;
+ // add 25% margin to avoid hash collisions
+ min_hash_size += min_hash_size / 4;
+
+ // initialize hash table
+ if (galloc->hash_set.size < min_hash_size) {
+ ggml_hash_set_free(&galloc->hash_set);
+ galloc->hash_set = ggml_hash_set_new(min_hash_size);
+ GGML_ASSERT(galloc->hash_set.keys != NULL);
+
+ free(galloc->hash_values);
+ galloc->hash_values = malloc(sizeof(struct hash_node) * galloc->hash_set.size);
+ GGML_ASSERT(galloc->hash_values != NULL);
+ }
+
+ // reset allocators
+ for (int i = 0; i < galloc->n_buffers; i++) {
+ ggml_dyn_tallocr_reset(galloc->buf_tallocs[i]);
+ }
+
+ // allocate in hash table
+ ggml_gallocr_alloc_graph_impl(galloc, graph, node_buffer_ids, leaf_buffer_ids);
+
+ // set the node_allocs from the hash table
+ if (galloc->n_nodes < graph->n_nodes) {
+ free(galloc->node_allocs);
+ galloc->node_allocs = calloc(graph->n_nodes, sizeof(struct node_alloc));
+ GGML_ASSERT(galloc->node_allocs != NULL);
+ }
+ galloc->n_nodes = graph->n_nodes;
+ for (int i = 0; i < graph->n_nodes; i++) {
+ struct ggml_tensor * node = graph->nodes[i];
+ struct node_alloc * node_alloc = &galloc->node_allocs[i];
+ if (node->view_src || node->data) {
+ node_alloc->dst.buffer_id = -1;
+ node_alloc->dst.addr = GGML_BUFFER_ADDRESS_INVALID;
+ node_alloc->dst.size_max = 0;
+ } else {
+ struct hash_node * hn = ggml_gallocr_hash_get(galloc, node);
+ node_alloc->dst.buffer_id = hn->buffer_id;
+ node_alloc->dst.addr = hn->addr;
+ node_alloc->dst.size_max = ggml_backend_buft_get_alloc_size(galloc->bufts[hn->buffer_id], node);
+ }
+ for (int j = 0; j < GGML_MAX_SRC; j++) {
+ struct ggml_tensor * src = node->src[j];
+ if (!src || src->view_src || src->data) {
+ node_alloc->src[j].buffer_id = -1;
+ node_alloc->src[j].addr = GGML_BUFFER_ADDRESS_INVALID;
+ node_alloc->src[j].size_max = 0;
+ } else {
+ struct hash_node * hn = ggml_gallocr_hash_get(galloc, src);
+ node_alloc->src[j].buffer_id = hn->buffer_id;
+ node_alloc->src[j].addr = hn->addr;
+ node_alloc->src[j].size_max = ggml_backend_buft_get_alloc_size(galloc->bufts[hn->buffer_id], src);
+ }
+ }
+ }
+ if (galloc->n_leafs < graph->n_leafs) {
+ free(galloc->leaf_allocs);
+ galloc->leaf_allocs = calloc(graph->n_leafs, sizeof(galloc->leaf_allocs[0]));
+ GGML_ASSERT(galloc->leaf_allocs != NULL);
+ }
+ galloc->n_leafs = graph->n_leafs;
+ for (int i = 0; i < graph->n_leafs; i++) {
+ struct ggml_tensor * leaf = graph->leafs[i];
+ struct hash_node * hn = ggml_gallocr_hash_get(galloc, leaf);
+ if (leaf->view_src || leaf->data) {
+ galloc->leaf_allocs[i].leaf.buffer_id = -1;
+ galloc->leaf_allocs[i].leaf.addr = GGML_BUFFER_ADDRESS_INVALID;
+ galloc->leaf_allocs[i].leaf.size_max = 0;
+ } else {
+ galloc->leaf_allocs[i].leaf.buffer_id = hn->buffer_id;
+ galloc->leaf_allocs[i].leaf.addr = hn->addr;
+ galloc->leaf_allocs[i].leaf.size_max = ggml_backend_buft_get_alloc_size(galloc->bufts[hn->buffer_id], leaf);
+ }
+ }
+
+ // reallocate buffers if needed
+ for (int i = 0; i < galloc->n_buffers; i++) {
+ // if the buffer type is used multiple times, we reuse the same buffer
+ for (int j = 0; j < i; j++) {
+ if (galloc->buf_tallocs[j] == galloc->buf_tallocs[i]) {
+ galloc->buffers[i] = galloc->buffers[j];
+ break;
+ }
+ }
+
+ // even if there are no tensors allocated in this buffer, we still need to allocate it to initialize views
+ bool realloc = galloc->buffers[i] == NULL;
+ size_t new_size = 0;
+ for (int c = 0; c < galloc->buf_tallocs[i]->n_chunks; c++) {
+ size_t cur_chunk_size = galloc->buffers[i] ? ggml_vbuffer_chunk_size(galloc->buffers[i], c) : 0;
+ size_t new_chunk_size = ggml_dyn_tallocr_max_size(galloc->buf_tallocs[i], c);
+ new_size += new_chunk_size;
+ if (new_chunk_size > cur_chunk_size) {
+ realloc = true;
+ }
+ }
+ if (realloc) {
+#ifndef NDEBUG
+ {
+ size_t cur_size = galloc->buffers[i] ? ggml_vbuffer_size(galloc->buffers[i]) : 0;
+ if (cur_size > 0) {
+ GGML_LOG_DEBUG("%s: reallocating %s buffer from size %.02f MiB to %.02f MiB\n",
+ __func__, ggml_backend_buft_name(galloc->bufts[i]), cur_size / 1024.0 / 1024.0, new_size / 1024.0 / 1024.0);
+ }
+ }
+#endif
+ ggml_vbuffer_free(galloc->buffers[i]);
+ if (no_alloc) {
+ galloc->buffers[i] = NULL;
+ } else {
+ galloc->buffers[i] = ggml_vbuffer_alloc(galloc->bufts[i], galloc->buf_tallocs[i], GGML_BACKEND_BUFFER_USAGE_COMPUTE);
+ if (galloc->buffers[i] == NULL) {
+ GGML_LOG_ERROR("%s: failed to allocate %s buffer of size %zu\n", __func__, ggml_backend_buft_name(galloc->bufts[i]), new_size);
+ return false;
+ }
+ }
+ }
+ }
+
+ return true;
+}
+
+void ggml_gallocr_reserve_n_size(
+ ggml_gallocr_t galloc, struct ggml_cgraph * graph, const int * node_buffer_ids, const int * leaf_buffer_ids, size_t * sizes) {
+ GGML_ASSERT(ggml_gallocr_reserve_n_impl(galloc, graph, node_buffer_ids, leaf_buffer_ids, /*no_alloc =*/ true));
+ for (int i = 0; i < galloc->n_buffers; i++) {
+ sizes[i] = 0;
+ for (int c = 0; c < galloc->buf_tallocs[i]->n_chunks; c++) {
+ sizes[i] += galloc->buf_tallocs[i]->chunks[c]->max_size;
+ }
+ }
+}
+
+bool ggml_gallocr_reserve_n(ggml_gallocr_t galloc, struct ggml_cgraph * graph, const int * node_buffer_ids, const int * leaf_buffer_ids) {
+ return ggml_gallocr_reserve_n_impl(galloc, graph, node_buffer_ids, leaf_buffer_ids, /*no_alloc =*/ false);
+}
+
+bool ggml_gallocr_reserve(ggml_gallocr_t galloc, struct ggml_cgraph *graph) {
+ return ggml_gallocr_reserve_n(galloc, graph, NULL, NULL);
+}
+
+static void ggml_gallocr_init_tensor(ggml_gallocr_t galloc, struct ggml_tensor * tensor, struct tensor_alloc * tensor_alloc) {
+ int buffer_id = tensor_alloc->buffer_id;
+ assert(tensor->data || tensor->view_src || ggml_backend_buft_get_alloc_size(galloc->bufts[buffer_id], tensor) <= tensor_alloc->size_max);
+
+ if (tensor->view_src != NULL) {
+ if (tensor->buffer == NULL) {
+ assert(tensor_alloc->addr.offset == SIZE_MAX);
+ if (tensor->view_src->buffer == NULL) {
+ // this tensor was allocated without ggml-backend
+ return;
+ }
+ ggml_backend_view_init(tensor);
+ }
+ } else {
+ if (tensor->data == NULL) {
+ assert(tensor_alloc->addr.offset != SIZE_MAX);
+ assert(ggml_backend_buft_get_alloc_size(galloc->bufts[buffer_id], tensor) <= tensor_alloc->size_max);
+ ggml_vbuffer_tensor_alloc(galloc->buffers[buffer_id], tensor, tensor_alloc->addr);
+ } else {
+ if (tensor->buffer == NULL) {
+ // this tensor was allocated without ggml-backend
+ return;
+ }
+ }
+ }
+}
+
+static bool ggml_gallocr_node_needs_realloc(ggml_gallocr_t galloc, struct ggml_tensor * node, struct tensor_alloc * talloc) {
+ size_t node_size = 0;
+ if (!node->data && !node->view_src) {
+ // If we previously had data but don't now then reallocate
+ if (talloc->buffer_id < 0) {
+ return false;
+ }
+ node_size = ggml_backend_buft_get_alloc_size(galloc->bufts[talloc->buffer_id], node);
+ }
+ return talloc->size_max >= node_size;
+}
+
+static bool ggml_gallocr_needs_realloc(ggml_gallocr_t galloc, struct ggml_cgraph * graph) {
+ if (galloc->n_nodes != graph->n_nodes) {
+#ifndef NDEBUG
+ GGML_LOG_DEBUG("%s: graph has different number of nodes\n", __func__);
+#endif
+ return true;
+ }
+
+ if (galloc->n_leafs != graph->n_leafs) {
+#ifndef NDEBUG
+ GGML_LOG_DEBUG("%s: graph has different number of leafs\n", __func__);
+#endif
+ return true;
+ }
+
+ for (int i = 0; i < graph->n_nodes; i++) {
+ struct ggml_tensor * node = graph->nodes[i];
+ struct node_alloc * node_alloc = &galloc->node_allocs[i];
+
+ if (!ggml_gallocr_node_needs_realloc(galloc, node, &node_alloc->dst)) {
+#ifndef NDEBUG
+ GGML_LOG_DEBUG("%s: node %s is not valid\n", __func__, node->name);
+#endif
+ return true;
+ }
+
+ for (int j = 0; j < GGML_MAX_SRC; j++) {
+ struct ggml_tensor * src = node->src[j];
+ if (src == NULL) {
+ continue;
+ }
+ if (!ggml_gallocr_node_needs_realloc(galloc, src, &node_alloc->src[j])) {
+#ifndef NDEBUG
+ GGML_LOG_DEBUG("%s: src %d (%s) of node %s is not valid\n", __func__, j, src->name, node->name);
+#endif
+ return true;
+ }
+ }
+ }
+
+ return false;
+}
+
+bool ggml_gallocr_alloc_graph(ggml_gallocr_t galloc, struct ggml_cgraph * graph) {
+ if (ggml_gallocr_needs_realloc(galloc, graph)) {
+ if (galloc->n_buffers == 1) {
+#ifndef NDEBUG
+ GGML_LOG_DEBUG("%s: reallocating buffers automatically\n", __func__);
+#endif
+ if (!ggml_gallocr_reserve(galloc, graph)) {
+ return false;
+ }
+ } else {
+#ifndef NDEBUG
+ GGML_LOG_DEBUG("%s: cannot reallocate multi buffer graph automatically, call reserve\n", __func__);
+#endif
+ return false;
+ }
+ }
+
+ // reset buffers
+ for (int i = 0; i < galloc->n_buffers; i++) {
+ if (galloc->buffers[i] != NULL) {
+ ggml_vbuffer_reset(galloc->buffers[i]);
+ }
+ }
+
+ // allocate the graph tensors from the previous assignments
+ // leafs
+ for (int i = 0; i < graph->n_leafs; i++) {
+ struct ggml_tensor * leaf = graph->leafs[i];
+ struct leaf_alloc * leaf_alloc = &galloc->leaf_allocs[i];
+ ggml_gallocr_init_tensor(galloc, leaf, &leaf_alloc->leaf);
+ }
+ // nodes
+ for (int i = 0; i < graph->n_nodes; i++) {
+ struct ggml_tensor * node = graph->nodes[i];
+ struct node_alloc * node_alloc = &galloc->node_allocs[i];
+ for (int j = 0; j < GGML_MAX_SRC; j++) {
+ struct ggml_tensor * src = node->src[j];
+ if (src == NULL) {
+ continue;
+ }
+ ggml_gallocr_init_tensor(galloc, src, &node_alloc->src[j]);
+ }
+ ggml_gallocr_init_tensor(galloc, node, &node_alloc->dst);
+ }
+
+ return true;
+}
+
+size_t ggml_gallocr_get_buffer_size(ggml_gallocr_t galloc, int buffer_id) {
+ GGML_ASSERT(buffer_id >= 0 && buffer_id < galloc->n_buffers);
+
+ if (galloc->buffers[buffer_id] == NULL) {
+ return 0;
+ }
+
+ for (int i = 0; i < buffer_id; i++) {
+ if (galloc->buffers[i] == galloc->buffers[buffer_id]) {
+ // this buffer is the same as a previous one due to the same buffer type being used multiple times
+ // only return the buffer size the first time it appears to avoid double counting
+ return 0;
+ }
+ }
+
+ return ggml_vbuffer_size(galloc->buffers[buffer_id]);
+}
+
+// utils
+
+static void free_buffers(ggml_backend_buffer_t ** buffers, const size_t * n_buffers) {
+ for (size_t i = 0; i < *n_buffers; i++) {
+ ggml_backend_buffer_free((*buffers)[i]);
+ }
+ free(*buffers);
+}
+
+static bool alloc_tensor_range(struct ggml_context * ctx,
+ struct ggml_tensor * first, struct ggml_tensor * last,
+ ggml_backend_buffer_type_t buft, size_t size,
+ ggml_backend_buffer_t ** buffers, size_t * n_buffers) {
+
+ ggml_backend_buffer_t buffer = ggml_backend_buft_alloc_buffer(buft, size);
+ if (buffer == NULL) {
+ GGML_LOG_ERROR("%s: failed to allocate %s buffer of size %zu\n", __func__, ggml_backend_buft_name(buft), size);
+ free_buffers(buffers, n_buffers);
+ return false;
+ }
+
+ *buffers = realloc(*buffers, sizeof(ggml_backend_buffer_t) * (*n_buffers + 1));
+ (*buffers)[(*n_buffers)++] = buffer;
+
+ struct ggml_tallocr tallocr = ggml_tallocr_new(buffer);
+
+ for (struct ggml_tensor * t = first; t != last; t = ggml_get_next_tensor(ctx, t)) {
+ enum ggml_status status = GGML_STATUS_SUCCESS;
+ if (t->data == NULL) {
+ if (t->view_src == NULL) {
+ status = ggml_tallocr_alloc(&tallocr, t);
+ } else if (t->buffer == NULL) {
+ status = ggml_backend_view_init(t);
+ }
+ } else {
+ if (t->view_src != NULL && t->buffer == NULL) {
+ // view of a pre-allocated tensor
+ status = ggml_backend_view_init(t);
+ }
+ }
+ if (status != GGML_STATUS_SUCCESS) {
+ GGML_LOG_ERROR("%s: failed to initialize tensor %s\n", __func__, t->name);
+ free_buffers(buffers, n_buffers);
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static ggml_backend_buffer_t ggml_backend_alloc_ctx_tensors_from_buft_impl(
+ struct ggml_context * ctx, ggml_backend_buffer_type_t buft, size_t * nbytes_total, bool no_alloc) {
+ GGML_ASSERT(ggml_get_no_alloc(ctx) == true);
+
+ size_t alignment = ggml_backend_buft_get_alignment(buft);
+ size_t max_size = ggml_backend_buft_get_max_size(buft);
+
+ ggml_backend_buffer_t * buffers = NULL;
+ size_t n_buffers = 0;
+ *nbytes_total = 0;
+
+ size_t cur_buf_size = 0;
+ struct ggml_tensor * first = ggml_get_first_tensor(ctx);
+ for (struct ggml_tensor * t = first; t != NULL; t = ggml_get_next_tensor(ctx, t)) {
+ size_t this_size = 0;
+ if (t->data == NULL && t->view_src == NULL) {
+ this_size = GGML_PAD(ggml_backend_buft_get_alloc_size(buft, t), alignment);
+ }
+
+ if (cur_buf_size > 0 && (cur_buf_size + this_size) > max_size) {
+ // allocate tensors in the current buffer
+ if (!no_alloc && !alloc_tensor_range(ctx, first, t, buft, cur_buf_size, &buffers, &n_buffers)) {
+ return NULL;
+ }
+ first = t;
+ *nbytes_total += cur_buf_size;
+ cur_buf_size = this_size;
+ } else {
+ cur_buf_size += this_size;
+ }
+ }
+
+ // allocate remaining tensors
+ if (cur_buf_size > 0) {
+ *nbytes_total += cur_buf_size;
+ if (!no_alloc && !alloc_tensor_range(ctx, first, NULL, buft, cur_buf_size, &buffers, &n_buffers)) {
+ return NULL;
+ }
+ }
+
+ if (no_alloc) {
+ return NULL;
+ }
+
+ if (n_buffers == 0) {
+#ifndef NDEBUG
+ GGML_LOG_DEBUG("%s: all tensors in the context are already allocated\n", __func__);
+#endif
+ GGML_ASSERT(!buffers);
+ return NULL;
+ }
+
+ ggml_backend_buffer_t buffer;
+ if (n_buffers == 1) {
+ buffer = buffers[0];
+ } else {
+ buffer = ggml_backend_multi_buffer_alloc_buffer(buffers, n_buffers);
+ }
+ if (buffers) {
+ free(buffers); // can be NULL if context is empty or no_alloc
+ }
+ return buffer;
+}
+
+size_t ggml_backend_alloc_ctx_tensors_from_buft_size(struct ggml_context * ctx, ggml_backend_buffer_type_t buft) {
+ size_t nbytes_total = 0;
+ ggml_backend_buffer_t buf = ggml_backend_alloc_ctx_tensors_from_buft_impl(ctx, buft, &nbytes_total, /*no_alloc=*/ true);
+ GGML_ASSERT(!buf);
+ return nbytes_total;
+}
+
+ggml_backend_buffer_t ggml_backend_alloc_ctx_tensors_from_buft(struct ggml_context * ctx, ggml_backend_buffer_type_t buft) {
+ size_t nbytes_total = 0;
+ return ggml_backend_alloc_ctx_tensors_from_buft_impl(ctx, buft, &nbytes_total, /*no_alloc =*/ false);
+}
+
+ggml_backend_buffer_t ggml_backend_alloc_ctx_tensors(struct ggml_context * ctx, ggml_backend_t backend) {
+ return ggml_backend_alloc_ctx_tensors_from_buft(ctx, ggml_backend_get_default_buffer_type(backend));
+}