KBaba7/llama.cpp
0
1#include "ggml.h"2#include "ggml-alloc.h"3#include "gguf.h"4 5#include "arg.h"6#include "common.h"7 8#include <map>9#include <vector>10#include <string>11#include <fstream>12 13static bool g_verbose = false;14 15struct tensor_transformation {16 struct ggml_tensor * in;17 struct ggml_tensor * out;18 bool is_copy;19};20 21static std::string get_kv_str(struct gguf_context * ctx_gguf, const std::string & key){22 int id = gguf_find_key(ctx_gguf, key.c_str());23 return id < 0 ? "" : std::string(gguf_get_val_str(ctx_gguf, id));24}25 26static float get_kv_f32(struct gguf_context * ctx_gguf, const std::string & key) {27 int id = gguf_find_key(ctx_gguf, key.c_str());28 return id < 0 ? 0.0f : gguf_get_val_f32(ctx_gguf, id);29}30 31static void zeros(std::ofstream & file, size_t n) {32 char zero = 0;33 for (size_t i = 0; i < n; ++i) {34 file.write(&zero, 1);35 }36}37 38static std::string ggml_ne_string(const ggml_tensor * t) {39 std::string str;40 for (int i = 0; i < GGML_MAX_DIMS; ++i) {41 str += std::to_string(t->ne[i]);42 if (i + 1 < GGML_MAX_DIMS) {43 str += ", ";44 }45 }46 return str;47}48 49static struct gguf_context * load_gguf(std::string & fname, struct ggml_context ** ctx_ggml) {50 struct gguf_init_params params = {51 /*.no_alloc = */ true,52 /*.ctx = */ ctx_ggml,53 };54 struct gguf_context * ctx_gguf = gguf_init_from_file(fname.c_str(), params);55 if (!ctx_gguf) {56 throw std::runtime_error("failed to load input GGUF from " + fname);57 }58 return ctx_gguf;59}60 61struct file_input {62 struct ggml_context * ctx_meta = nullptr;63 struct gguf_context * ctx_gguf = nullptr;64 std::ifstream f_in;65 std::map<std::string, ggml_tensor *> tensors;66 float alpha;67 float scale;68 69 file_input(std::string & fname, float scale): f_in(fname, std::ios::binary), scale(scale) {70 if (!f_in.is_open()) {71 throw std::runtime_error("failed to open input gguf from " + fname);72 }73 74 ctx_gguf = load_gguf(fname, &ctx_meta);75 alpha = get_kv_f32(ctx_gguf, "adapter.lora.alpha");76 printf("%s: loaded gguf from %s\n", __func__, fname.c_str());77 78 for (ggml_tensor * cur = ggml_get_first_tensor(ctx_meta); cur; cur = ggml_get_next_tensor(ctx_meta, cur)) {79 std::string name(cur->name);80 tensors[name] = cur;81 if (g_verbose) {82 printf("%s: %s\n", __func__, cur->name);83 }84 }85 }86 87 ggml_tensor * get_tensor(std::string name) {88 if (tensors.find(name) == tensors.end()) {89 return nullptr;90 }91 return tensors[name];92 }93 94 void read_tensor_data(std::string name, std::vector<uint8_t> & buf) {95 if (tensors.find(name) == tensors.end()) {96 throw std::runtime_error("cannot find tensor with name: " + name);97 }98 auto len = ggml_nbytes(tensors[name]);99 if (buf.size() < len) {100 buf.resize(len);101 }102 auto i_tensor_in = gguf_find_tensor(ctx_gguf, name.c_str()); // idx of tensor in the input file103 auto offset = gguf_get_data_offset(ctx_gguf) + gguf_get_tensor_offset(ctx_gguf, i_tensor_in);104 f_in.seekg(offset);105 f_in.read((char* )buf.data(), len);106 }107 108 ~file_input() {109 gguf_free(ctx_gguf);110 ggml_free(ctx_meta);111 }112};113 114struct lora_merge_ctx {115 // input base model + adapters116 file_input base_model;117 std::vector<std::unique_ptr<file_input>> adapters;118 119 // for computing merged tensor120 int n_threads;121 ggml_backend_t backend = nullptr;122 ggml_gallocr_t allocr = nullptr;123 std::vector<uint8_t> read_buf;124 125 // output file126 struct gguf_context * ctx_out;127 struct ggml_context * ctx_out_ggml;128 std::ofstream fout;129 130 lora_merge_ctx(131 std::string & base_fname,132 std::vector<common_adapter_lora_info> & lora_files,133 std::string & outfile,134 int n_threads) : base_model(base_fname, 0), n_threads(n_threads), fout(outfile, std::ios::binary) {135 fout.exceptions(std::ofstream::failbit); // fail fast on write errors136 137 if (gguf_find_key(base_model.ctx_gguf, LLM_KV_SPLIT_COUNT) >= 0) {138 throw std::runtime_error("split model is not yet supported");139 }140 141 for (auto & lora_inp : lora_files) {142 auto fname = lora_inp.path;143 auto scale = lora_inp.scale;144 std::unique_ptr<file_input> adapter(new file_input(fname, scale));145 check_metadata_lora(adapter.get());146 adapters.push_back(std::move(adapter));147 }148 149 ctx_out = gguf_init_empty();150 struct ggml_init_params params = {151 /*.mem_size =*/ gguf_get_n_tensors(base_model.ctx_gguf)*ggml_tensor_overhead(),152 /*.mem_buffer =*/ NULL,153 /*.no_alloc =*/ true,154 };155 ctx_out_ggml = ggml_init(params);156 backend = ggml_backend_cpu_init();157 allocr = ggml_gallocr_new(ggml_backend_get_default_buffer_type(backend));158 }159 160 void check_metadata_lora(file_input * adapter) {161 auto general_type = get_kv_str(adapter->ctx_gguf, "general.type");162 if (general_type != "adapter") {163 throw std::runtime_error("expect general.type to be 'adapter', but got: " + general_type);164 }165 166 auto adapter_type = get_kv_str(adapter->ctx_gguf, "adapter.type");167 if (adapter_type != "lora") {168 throw std::runtime_error("expect adapter.type to be 'lora', but got: " + adapter_type);169 }170 171 auto general_arch_base = get_kv_str(base_model.ctx_gguf, "general.architecture");172 auto general_arch_lora = get_kv_str(adapter->ctx_gguf, "general.architecture");173 if (general_arch_base != general_arch_lora) {174 throw std::runtime_error("model arch and LoRA arch mismatch");175 }176 }177 178 ggml_type get_out_tensor_type(struct ggml_tensor * t) {179 if (t->type == GGML_TYPE_F32) {180 return GGML_TYPE_F32;181 } else {182 return GGML_TYPE_F16;183 }184 }185 186 void run_merge() {187 // prepare metadata188 gguf_set_kv(ctx_out, base_model.ctx_gguf);189 // output is forced to f16 for now190 gguf_set_val_u32(ctx_out, "general.file_type", LLAMA_FTYPE_MOSTLY_F16);191 192 // check if all lora adapters have the same tensors193 // TODO: remove this when we can support merging subset of adapters. Ref: https://github.com/ggerganov/llama.cpp/pull/8607#discussion_r1686027777194 static const char * err_no_subset_adapter = "Input adapters do not have the same list of tensors. This is not yet supported. Please merge the adapter one-by-one instead of merging all at once.";195 if (adapters.size() > 1) {196 for (size_t i = 1; i < adapters.size(); ++i) {197 if (adapters[0]->tensors.size() != adapters[i]->tensors.size()) {198 throw std::runtime_error(err_no_subset_adapter);199 }200 for (auto & it : adapters[i]->tensors) {201 if (adapters[0]->get_tensor(it.first) == nullptr) {202 throw std::runtime_error(err_no_subset_adapter);203 }204 }205 }206 }207 208 // mapping base tensor to out tensor (same shape with base, but different type)209 std::vector<tensor_transformation> trans;210 for (auto & it : base_model.tensors) {211 bool t_a = true;212 bool t_b = true;213 for (auto & adapter : adapters) {214 t_a &= nullptr != adapter->get_tensor(it.first + ".lora_a");215 t_b &= nullptr != adapter->get_tensor(it.first + ".lora_b");216 }217 auto base_tensor = it.second;218 if (!t_a && !t_b) {219 // only copy220 struct ggml_tensor * cpy_tensor = ggml_dup_tensor(ctx_out_ggml, base_tensor);221 ggml_set_name(cpy_tensor, base_tensor->name);222 trans.push_back({223 cpy_tensor,224 cpy_tensor,225 true,226 });227 gguf_add_tensor(ctx_out, cpy_tensor);228 } else if (t_a && t_b) {229 // need merging230 struct ggml_tensor * out_tensor = ggml_new_tensor(231 ctx_out_ggml, get_out_tensor_type(base_tensor), GGML_MAX_DIMS, base_tensor->ne);232 ggml_set_name(out_tensor, base_tensor->name);233 trans.push_back({234 base_tensor,235 out_tensor,236 false,237 });238 gguf_add_tensor(ctx_out, out_tensor);239 } else {240 throw std::runtime_error("tensor " + it.first + " missing either lora_a or lora_b");241 }242 }243 244 // placeholder for the meta data245 {246 size_t meta_size = gguf_get_meta_size(ctx_out);247 zeros(fout, meta_size);248 }249 250 // process base model tensors251 size_t n_merged = 0;252 for (auto & it : trans) {253 if (!it.is_copy) {254 merge_tensor(it.in, it.out);255 n_merged++;256 } else {257 copy_tensor(it.in);258 }259 }260 261 // write output metadata262 {263 std::vector<uint8_t> data(gguf_get_meta_size(ctx_out));264 gguf_get_meta_data(ctx_out, data.data());265 fout.seekp(0);266 fout.write((const char *)data.data(), data.size());267 }268 269 printf("%s : merged %zu tensors with lora adapters\n", __func__, n_merged);270 printf("%s : wrote %zu tensors to output file\n", __func__, trans.size());271 }272 273 void copy_tensor(struct ggml_tensor * base) {274 printf("%s : %s [%s]\n", __func__, base->name, ggml_ne_string(base).c_str());275 size_t len = ggml_nbytes(base);276 base_model.read_tensor_data(base->name, read_buf);277 fout.write((char* )read_buf.data(), len);278 zeros(fout, GGML_PAD(len, GGUF_DEFAULT_ALIGNMENT) - len);279 }280 281 void merge_tensor(struct ggml_tensor * base, struct ggml_tensor * out) {282 std::string name_base(base->name);283 std::string name_lora_a = name_base + ".lora_a";284 std::string name_lora_b = name_base + ".lora_b";285 286 printf("%s : %s [%s]\n", __func__, base->name, ggml_ne_string(base).c_str());287 288 // context for input tensor289 std::vector<struct ggml_tensor *> inp_a(adapters.size());290 std::vector<struct ggml_tensor *> inp_b(adapters.size());291 struct ggml_init_params params {292 /*.mem_size =*/ ggml_tensor_overhead()*(2+adapters.size()*2),293 /*.mem_buffer =*/ NULL,294 /*.no_alloc =*/ true,295 };296 struct ggml_context * ctx = ggml_init(params);297 298 // alloc tensors299 struct ggml_tensor * inp_base = ggml_new_tensor(ctx, GGML_TYPE_F32, GGML_MAX_DIMS, base->ne);300 for (size_t i = 0; i < adapters.size(); ++i) {301 auto t_a = adapters[i]->get_tensor(name_lora_a);302 auto t_b = adapters[i]->get_tensor(name_lora_b);303 // TODO: add support for quantized lora304 if (ggml_is_quantized(t_a->type) || ggml_is_quantized(t_b->type)) {305 throw std::runtime_error("quantized LoRA adapters is not supported, please retry with f16 or f32");306 }307 inp_a[i] = ggml_dup_tensor(ctx, t_a);308 inp_b[i] = ggml_dup_tensor(ctx, t_b);309 }310 ggml_backend_buffer_t buffer = ggml_backend_alloc_ctx_tensors(ctx, backend);311 312 // load base tensor to backend buffer313 base_model.read_tensor_data(name_base, read_buf);314 if (base->type != GGML_TYPE_F32) {315 // optionally dequantize it316 printf("%s : + dequantize base tensor from %s to F32\n", __func__, ggml_type_name(base->type));317 auto nels = ggml_nelements(inp_base);318 const auto * qtype = ggml_get_type_traits(base->type);319 std::vector<uint8_t> dequant_buf(nels * sizeof(float));320 qtype->to_float(read_buf.data(), (float *)dequant_buf.data(), nels);321 ggml_backend_tensor_set(inp_base, dequant_buf.data(), 0, dequant_buf.size());322 } else {323 ggml_backend_tensor_set(inp_base, read_buf.data(), 0, ggml_nbytes(inp_base));324 }325 326 // load lora tensors to backend buffer327 for (size_t i = 0; i < adapters.size(); ++i) {328 adapters[i]->read_tensor_data(name_lora_a, read_buf);329 ggml_backend_tensor_set(inp_a[i], read_buf.data(), 0, ggml_nbytes(inp_a[i]));330 adapters[i]->read_tensor_data(name_lora_b, read_buf);331 ggml_backend_tensor_set(inp_b[i], read_buf.data(), 0, ggml_nbytes(inp_b[i]));332 }333 334 // build graph335 struct ggml_cgraph * gf;336 {337 static size_t buf_size = ggml_tensor_overhead()*GGML_DEFAULT_GRAPH_SIZE + ggml_graph_overhead();338 static std::vector<uint8_t> buf(buf_size);339 struct ggml_init_params params0 = {340 /*.mem_size =*/ buf_size,341 /*.mem_buffer =*/ buf.data(),342 /*.no_alloc =*/ true,343 };344 struct ggml_context * ctx0 = ggml_init(params0);345 gf = ggml_new_graph(ctx0);346 struct ggml_tensor * cur = inp_base;347 for (size_t i = 0; i < adapters.size(); ++i) {348 struct ggml_tensor * delta;349 bool is_tok_embd = string_starts_with(name_base, "token_embd");350 if (is_tok_embd) {351 printf("%s : detected token embeddings tensor\n", __func__);352 delta = ggml_mul_mat(ctx0,353 ggml_cast(ctx0, inp_b[i], GGML_TYPE_F32),354 ggml_cast(ctx0, inp_a[i], GGML_TYPE_F32));355 } else {356 delta = ggml_mul_mat(ctx0,357 ggml_cont(ctx0, ggml_transpose(ctx0, ggml_cast(ctx0, inp_a[i], GGML_TYPE_F32))),358 ggml_cast(ctx0, inp_b[i], GGML_TYPE_F32));359 }360 // scale361 const float alpha = adapters[i]->alpha;362 const float rank = (float) inp_b[i]->ne[0];363 const float scale = alpha ? adapters[i]->scale * alpha / rank : adapters[i]->scale;364 delta = ggml_scale(ctx0, delta, scale);365 cur = ggml_add(ctx0, delta, cur);366 printf("%s : + merging from adapter[%zu] type=%s\n", __func__, i, ggml_type_name(inp_a[i]->type));367 printf("%s : input_scale=%f calculated_scale=%f rank=%d\n", __func__, adapters[i]->scale, scale, (int) inp_b[i]->ne[0]);368 }369 cur = ggml_cast(ctx0, cur, out->type);370 printf("%s : + output type is %s\n", __func__, ggml_type_name(out->type));371 ggml_build_forward_expand(gf, cur);372 ggml_free(ctx0);373 }374 375 // compute376 {377 ggml_gallocr_alloc_graph(allocr, gf);378 ggml_backend_cpu_set_n_threads(backend, n_threads);379 ggml_backend_graph_compute(backend, gf);380 }381 382 // write data to output file383 {384 auto * result = ggml_graph_node(gf, -1);385 size_t len = ggml_nbytes(result);386 if (read_buf.size() < len) {387 read_buf.resize(len);388 }389 ggml_backend_tensor_get(result, read_buf.data(), 0, len);390 fout.write((char* )read_buf.data(), len);391 zeros(fout, GGML_PAD(len, GGUF_DEFAULT_ALIGNMENT) - len);392 }393 394 ggml_free(ctx);395 ggml_backend_buffer_free(buffer);396 }397 398 ~lora_merge_ctx() {399 ggml_gallocr_free(allocr);400 ggml_backend_free(backend);401 gguf_free(ctx_out);402 ggml_free(ctx_out_ggml);403 }404};405 406static void print_usage(int, char ** argv) {407 printf("\nexample usage:\n");408 printf("\n %s -m base-model.gguf --lora lora-file.gguf -o merged-model-f16.gguf\n", argv[0]);409 printf("\nNOTE: output model is F16\n");410 printf("\n");411}412 413int main(int argc, char ** argv) {414 common_params params;415 416 if (!common_params_parse(argc, argv, params, LLAMA_EXAMPLE_EXPORT_LORA, print_usage)) {417 return 1;418 }419 420 g_verbose = (params.verbosity > 1);421 try {422 lora_merge_ctx ctx(params.model, params.lora_adapters, params.lora_outfile, params.cpuparams.n_threads);423 ctx.run_merge();424 } catch (const std::exception & err) {425 fprintf(stderr, "%s\n", err.what());426 exit(EXIT_FAILURE);427 }428 429 printf("done, output file is %s\n", params.lora_outfile.c_str());430 431 return 0;432}433 