#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(...)
// 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_CLAMP:
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 - 1; 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_impl_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_impl_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_impl_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_impl_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;
if (ggml_backend_buft_is_meta(buft)) {
return ggml_backend_meta_alloc_ctx_tensors_from_buft(ctx, buft);
}
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));
}