move BLAS to a separate backend (#6210)

* move BLAS to a separate backend

* rename GGML_USE_OPENBLAS to GGML_USE_BLAS

* alloc : reuse same buffer when the same buffer type if used multiple times

* set number of threads automatically for openblas and blis

* sched : print assignments when GGML_SCHED_DEBUG env variable is set

* sched : allow ops with weights on an incompatible buffer type

This will cause the weight to be copied to a backend that supports the
op, which is very costly. The weight should have been stored in a buffer
of a backend that can run the op, but llama.cpp cannot do this
automatically at the moment.

---------

Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
This commit is contained in:
slaren 2024-06-13 03:11:35 +02:00 committed by GitHub
parent 1c641e6aac
commit f578b86b21
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
17 changed files with 821 additions and 379 deletions

View file

@ -339,6 +339,7 @@ struct hash_node {
};
struct tensor_alloc {
int buffer_id;
size_t offset;
size_t size_max; // 0 = pre-allocated, unused, or view
};
@ -349,7 +350,6 @@ struct leaf_alloc {
};
struct node_alloc {
int buffer_id;
struct tensor_alloc dst;
struct tensor_alloc src[GGML_MAX_SRC];
};
@ -386,8 +386,19 @@ ggml_gallocr_t ggml_gallocr_new_n(ggml_backend_buffer_type_t * bufts, int n_bufs
for (int i = 0; i < n_bufs; i++) {
galloc->bufts[i] = bufts[i];
galloc->buffers[i] = NULL;
size_t alignment = ggml_backend_buft_get_alignment(bufts[i]);
galloc->buf_tallocs[i] = ggml_dyn_tallocr_new(alignment);
// 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]);
galloc->buf_tallocs[i] = ggml_dyn_tallocr_new(alignment);
}
}
galloc->n_buffers = n_bufs;
@ -405,10 +416,30 @@ void ggml_gallocr_free(ggml_gallocr_t galloc) {
for (int i = 0; i < galloc->n_buffers; i++) {
if (galloc->buffers != NULL) {
ggml_backend_buffer_free(galloc->buffers[i]);
// 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_backend_buffer_free(galloc->buffers[i]);
}
}
if (galloc->buf_tallocs != NULL) {
ggml_dyn_tallocr_free(galloc->buf_tallocs[i]);
// 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]);
}
}
}
@ -511,17 +542,18 @@ static void ggml_gallocr_allocate_node(ggml_gallocr_t galloc, struct ggml_tensor
}
}
static void ggml_gallocr_free_node(ggml_gallocr_t galloc, struct ggml_tensor * node, int buffer_id) {
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 ggml_dyn_tallocr * alloc = galloc->buf_tallocs[buffer_id];
ggml_backend_buffer_type_t buft = galloc->bufts[buffer_id];
struct hash_node * hn = ggml_gallocr_hash_get(galloc, node);
size_t offset = hn->offset;
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);
ggml_dyn_tallocr_free_tensor(alloc, offset, size, node);
hn->allocated = false;
@ -626,11 +658,11 @@ static void ggml_gallocr_alloc_graph_impl(ggml_gallocr_t galloc, struct ggml_cgr
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, buffer_id);
ggml_gallocr_free_node(galloc, view_src);
}
}
else if (p_hn->allocated) {
ggml_gallocr_free_node(galloc, parent, buffer_id);
ggml_gallocr_free_node(galloc, parent);
}
}
AT_PRINTF("\n");
@ -674,22 +706,25 @@ bool ggml_gallocr_reserve_n(ggml_gallocr_t galloc, struct ggml_cgraph * graph, c
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];
node_alloc->buffer_id = get_node_buffer_id(node_buffer_ids, i);
if (node->view_src || node->data) {
node_alloc->dst.buffer_id = -1;
node_alloc->dst.offset = SIZE_MAX;
node_alloc->dst.size_max = 0;
} else {
struct hash_node * hn = ggml_gallocr_hash_get(galloc, node);
node_alloc->dst.offset = hn->offset;
node_alloc->dst.size_max = ggml_backend_buft_get_alloc_size(galloc->bufts[hn->buffer_id], node);
node_alloc->dst.buffer_id = hn->buffer_id;
node_alloc->dst.offset = hn->offset;
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].offset = SIZE_MAX;
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].offset = hn->offset;
node_alloc->src[j].size_max = ggml_backend_buft_get_alloc_size(galloc->bufts[hn->buffer_id], src);
}
@ -706,9 +741,11 @@ bool ggml_gallocr_reserve_n(ggml_gallocr_t galloc, struct ggml_cgraph * graph, c
struct hash_node * hn = ggml_gallocr_hash_get(galloc, leaf);
galloc->leaf_allocs[i].buffer_id = hn->buffer_id;
if (leaf->view_src || leaf->data) {
galloc->leaf_allocs[i].leaf.buffer_id = -1;
galloc->leaf_allocs[i].leaf.offset = SIZE_MAX;
galloc->leaf_allocs[i].leaf.size_max = 0;
} else {
galloc->leaf_allocs[i].leaf.buffer_id = hn->buffer_id;
galloc->leaf_allocs[i].leaf.offset = hn->offset;
galloc->leaf_allocs[i].leaf.size_max = ggml_backend_buft_get_alloc_size(galloc->bufts[hn->buffer_id], leaf);
}
@ -716,6 +753,14 @@ bool ggml_gallocr_reserve_n(ggml_gallocr_t galloc, struct ggml_cgraph * graph, c
// 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;
}
}
size_t cur_size = galloc->buffers[i] ? ggml_backend_buffer_get_size(galloc->buffers[i]) : 0;
size_t new_size = ggml_dyn_tallocr_max_size(galloc->buf_tallocs[i]);
@ -724,6 +769,7 @@ bool ggml_gallocr_reserve_n(ggml_gallocr_t galloc, struct ggml_cgraph * graph, c
#ifndef NDEBUG
fprintf(stderr, "%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_backend_buffer_free(galloc->buffers[i]);
galloc->buffers[i] = ggml_backend_buft_alloc_buffer(galloc->bufts[i], new_size);
if (galloc->buffers[i] == NULL) {
@ -740,7 +786,8 @@ 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, int buffer_id, struct tensor_alloc * tensor_alloc) {
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_buffer_get_alloc_size(galloc->buffers[buffer_id], tensor) <= tensor_alloc->size_max);
if (tensor->view_src != NULL) {
@ -768,8 +815,8 @@ static void ggml_gallocr_init_tensor(ggml_gallocr_t galloc, struct ggml_tensor *
}
}
static bool ggml_gallocr_node_needs_realloc(ggml_gallocr_t galloc, struct ggml_tensor * node, struct node_alloc * nalloc, struct tensor_alloc * talloc) {
ggml_backend_buffer_type_t buft = galloc->bufts[nalloc->buffer_id];
static bool ggml_gallocr_node_needs_realloc(ggml_gallocr_t galloc, struct ggml_tensor * node, struct tensor_alloc * talloc) {
ggml_backend_buffer_type_t buft = talloc->buffer_id != -1 ? galloc->bufts[talloc->buffer_id] : NULL;
size_t node_size = (node->data || node->view_src) ? 0 : ggml_backend_buft_get_alloc_size(buft, node);
return talloc->size_max >= node_size;
}
@ -793,7 +840,7 @@ static bool ggml_gallocr_needs_realloc(ggml_gallocr_t galloc, struct ggml_cgraph
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, &node_alloc->dst)) {
if (!ggml_gallocr_node_needs_realloc(galloc, node, &node_alloc->dst)) {
#ifndef NDEBUG
fprintf(stderr, "%s: node %s is not valid\n", __func__, node->name);
#endif
@ -805,7 +852,7 @@ static bool ggml_gallocr_needs_realloc(ggml_gallocr_t galloc, struct ggml_cgraph
if (src == NULL) {
continue;
}
if (!ggml_gallocr_node_needs_realloc(galloc, src, node_alloc, &node_alloc->src[j])) {
if (!ggml_gallocr_node_needs_realloc(galloc, src, &node_alloc->src[j])) {
#ifndef NDEBUG
fprintf(stderr, "%s: src %d (%s) of node %s is not valid\n", __func__, j, src->name, node->name);
#endif
@ -846,7 +893,7 @@ bool ggml_gallocr_alloc_graph(ggml_gallocr_t galloc, struct ggml_cgraph * graph)
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->buffer_id, &leaf_alloc->leaf);
ggml_gallocr_init_tensor(galloc, leaf, &leaf_alloc->leaf);
}
// nodes
for (int i = 0; i < graph->n_nodes; i++) {
@ -857,9 +904,9 @@ bool ggml_gallocr_alloc_graph(ggml_gallocr_t galloc, struct ggml_cgraph * graph)
if (src == NULL) {
continue;
}
ggml_gallocr_init_tensor(galloc, src, node_alloc->buffer_id, &node_alloc->src[j]);
ggml_gallocr_init_tensor(galloc, src, &node_alloc->src[j]);
}
ggml_gallocr_init_tensor(galloc, node, node_alloc->buffer_id, &node_alloc->dst);
ggml_gallocr_init_tensor(galloc, node, &node_alloc->dst);
}
return true;
@ -871,6 +918,15 @@ size_t ggml_gallocr_get_buffer_size(ggml_gallocr_t galloc, int buffer_id) {
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_backend_buffer_get_size(galloc->buffers[buffer_id]);
}