KBaba7/llama.cpp
0
1#include "llama-adapter.h"2 3#include "llama-impl.h"4#include "llama-mmap.h"5#include "llama-model.h"6 7#include <algorithm>8#include <map>9#include <cassert>10#include <stdexcept>11 12// vec13 14struct ggml_tensor * llama_adapter_cvec::tensor_for(int il) const {15 if (il < 0 || il < layer_start || il > layer_end || (size_t) il >= tensors.size()) {16 return nullptr;17 }18 19 return tensors[il];20}21 22struct ggml_tensor * llama_adapter_cvec::apply_to(struct ggml_context * ctx, struct ggml_tensor * cur, int il) const {23 ggml_tensor * layer_dir = tensor_for(il);24 if (layer_dir != nullptr) {25 cur = ggml_add(ctx, cur, layer_dir);26 }27 28 return cur;29}30 31bool llama_adapter_cvec::init(const llama_model & model) {32 const auto & hparams = model.hparams;33 34 GGML_ASSERT(tensors.empty());35 GGML_ASSERT(ctxs.empty());36 GGML_ASSERT(bufs.empty());37 38 // create a context for each buffer type39 std::map<ggml_backend_buffer_type_t, ggml_context *> ctx_map;40 auto ctx_for_buft = [&](ggml_backend_buffer_type_t buft) -> ggml_context * {41 auto it = ctx_map.find(buft);42 if (it == ctx_map.end()) {43 struct ggml_init_params params = {44 /*.mem_size =*/ hparams.n_layer*ggml_tensor_overhead(),45 /*.mem_buffer =*/ NULL,46 /*.no_alloc =*/ true,47 };48 49 ggml_context * ctx = ggml_init(params);50 if (!ctx) {51 return nullptr;52 }53 54 ctx_map[buft] = ctx;55 ctxs.emplace_back(ctx);56 57 return ctx;58 }59 60 return it->second;61 };62 63 // make tensors64 tensors.reserve(hparams.n_layer);65 tensors.push_back(nullptr); // there's never a tensor for layer 066 for (size_t il = 1; il < hparams.n_layer; il++) {67 ggml_backend_buffer_type_t buft = model.select_buft(il);68 ggml_context * ctx = ctx_for_buft(buft);69 if (!ctx) {70 LLAMA_LOG_ERROR("%s: failed to allocate context for control vector\n", __func__);71 return false;72 }73 ggml_tensor * tensor = ggml_new_tensor_1d(ctx, GGML_TYPE_F32, hparams.n_embd);74 tensors.push_back(tensor);75 }76 77 // allocate tensors / buffers and zero78 bufs.reserve(ctx_map.size());79 for (auto it : ctx_map) {80 ggml_backend_buffer_type_t buft = it.first;81 ggml_context * ctx = it.second;82 ggml_backend_buffer_t buf = ggml_backend_alloc_ctx_tensors_from_buft(ctx, buft);83 if (!buf) {84 LLAMA_LOG_ERROR("%s: failed to allocate buffer for control vector\n", __func__);85 return false;86 }87 ggml_backend_buffer_clear(buf, 0);88 bufs.emplace_back(buf);89 }90 91 return true;92}93 94int32_t llama_adapter_cvec::apply(95 const llama_model & model,96 const float * data,97 size_t len,98 int32_t n_embd,99 int32_t il_start,100 int32_t il_end) {101 const auto & hparams = model.hparams;102 103 if (data == nullptr) {104 // disable the current control vector (but leave allocated for later)105 layer_start = -1;106 layer_end = -1;107 return 0;108 }109 110 if (n_embd != (int) hparams.n_embd) {111 LLAMA_LOG_ERROR("%s: control vector n_embd does not match model\n", __func__);112 return 1;113 }114 115 if (tensors.empty()) {116 if (!init(model)) {117 return 1;118 }119 }120 121 layer_start = il_start;122 layer_end = il_end;123 124 for (size_t il = 1; il < hparams.n_layer; il++) {125 assert(tensors[il] != nullptr);126 127 const size_t off = n_embd * (il - 1); // buffer doesn't have data for layer 0, since it's never present128 if (off + n_embd <= len) {129 ggml_backend_tensor_set(tensors[il], data + off, 0, n_embd * ggml_element_size(tensors[il]));130 }131 }132 133 return 0;134}135 136// lora137 138llama_adapter_lora_weight * llama_adapter_lora::get_weight(struct ggml_tensor * w) {139 const std::string name(w->name);140 141 const auto pos = ab_map.find(name);142 if (pos != ab_map.end()) {143 return &pos->second;144 }145 146 return nullptr;147}148 149static void llama_adapter_lora_init_impl(struct llama_model & model, const char * path_lora, struct llama_adapter_lora & adapter) {150 LLAMA_LOG_INFO("%s: loading lora adapter from '%s' ...\n", __func__, path_lora);151 152 ggml_context * ctx_init;153 struct gguf_init_params meta_gguf_params = {154 /* .no_alloc = */ true,155 /* .ctx = */ &ctx_init,156 };157 158 gguf_context_ptr ctx_gguf { gguf_init_from_file(path_lora, meta_gguf_params) };159 if (!ctx_gguf) {160 throw std::runtime_error("failed to load lora adapter file from " + std::string(path_lora));161 }162 163 ggml_context_ptr ctx { ctx_init };164 165 // check metadata166 {167 auto get_kv_str = [&](const std::string & key) -> std::string {168 int id = gguf_find_key(ctx_gguf.get(), key.c_str());169 return id < 0 ? "" : std::string(gguf_get_val_str(ctx_gguf.get(), id));170 };171 auto get_kv_f32 = [&](const std::string & key) -> float {172 int id = gguf_find_key(ctx_gguf.get(), key.c_str());173 return id < 0 ? 0.0f : gguf_get_val_f32(ctx_gguf.get(), id);174 };175 LLM_KV llm_kv = LLM_KV(LLM_ARCH_UNKNOWN);176 177 auto general_type = get_kv_str(llm_kv(LLM_KV_GENERAL_TYPE));178 if (general_type != "adapter") {179 throw std::runtime_error("expect general.type to be 'adapter', but got: " + general_type);180 }181 182 auto general_arch_str = get_kv_str(llm_kv(LLM_KV_GENERAL_ARCHITECTURE));183 auto general_arch = llm_arch_from_string(general_arch_str);184 if (general_arch != model.arch) {185 throw std::runtime_error("model arch and LoRA arch mismatch");186 }187 188 auto adapter_type = get_kv_str(llm_kv(LLM_KV_ADAPTER_TYPE));189 if (adapter_type != "lora") {190 throw std::runtime_error("expect adapter.type to be 'lora', but got: " + adapter_type);191 }192 193 adapter.alpha = get_kv_f32(llm_kv(LLM_KV_ADAPTER_LORA_ALPHA));194 }195 196 int n_tensors = gguf_get_n_tensors(ctx_gguf.get());197 198 // contexts for each buffer type199 std::map<ggml_backend_buffer_type_t, ggml_context *> ctx_map;200 auto ctx_for_buft = [&](ggml_backend_buffer_type_t buft) -> ggml_context * {201 auto it = ctx_map.find(buft);202 if (it == ctx_map.end()) {203 // add a new context204 struct ggml_init_params params = {205 /*.mem_size =*/ n_tensors*ggml_tensor_overhead(),206 /*.mem_buffer =*/ NULL,207 /*.no_alloc =*/ true,208 };209 ggml_context * buft_ctx = ggml_init(params);210 if (!buft_ctx) {211 return nullptr;212 }213 ctx_map[buft] = buft_ctx;214 adapter.ctxs.emplace_back(buft_ctx);215 return buft_ctx;216 };217 return it->second;218 };219 220 // bundle lora_a and lora_b into pairs221 std::map<std::string, llama_adapter_lora_weight> ab_map;222 auto str_endswith = [](const std::string & str, const std::string & suffix) {223 return str.size() >= suffix.size() && str.compare(str.size()-suffix.size(), suffix.size(), suffix) == 0;224 };225 226 for (ggml_tensor * cur = ggml_get_first_tensor(ctx.get()); cur; cur = ggml_get_next_tensor(ctx.get(), cur)) {227 std::string name(cur->name);228 if (str_endswith(name, ".lora_a")) {229 replace_all(name, ".lora_a", "");230 if (ab_map.find(name) == ab_map.end()) {231 ab_map[name] = llama_adapter_lora_weight(cur, nullptr);232 } else {233 ab_map[name].a = cur;234 }235 } else if (str_endswith(name, ".lora_b")) {236 replace_all(name, ".lora_b", "");237 if (ab_map.find(name) == ab_map.end()) {238 ab_map[name] = llama_adapter_lora_weight(nullptr, cur);239 } else {240 ab_map[name].b = cur;241 }242 } else if (str_endswith(name, "_norm.weight")) {243 // TODO: add support for norm vector244 // for now, we don't really care because most adapters still work fine without it245 continue;246 } else {247 throw std::runtime_error("LoRA tensor '" + name + "' has unexpected suffix");248 }249 }250 251 // add tensors252 for (auto & it : ab_map) {253 const std::string & name = it.first;254 llama_adapter_lora_weight & w = it.second;255 bool is_token_embd = str_endswith(name, "token_embd.weight");256 257 if (!w.a || !w.b) {258 throw std::runtime_error("LoRA tensor pair for '" + name + "' is missing one component");259 }260 261 // device buft and device ctx262 const auto * model_tensor = model.get_tensor(name.c_str());263 if (!model_tensor) {264 throw std::runtime_error("LoRA tensor '" + name + "' does not exist in base model (hint: maybe wrong base model?)");265 }266 267 struct ggml_context * dev_ctx = ctx_for_buft(ggml_backend_buffer_get_type(model_tensor->buffer));268 // validate tensor shape269 if (is_token_embd) {270 // expect B to be non-transposed, A and B are flipped; see llm_build_inp_embd()271 if (model_tensor->ne[0] != w.b->ne[1] || model_tensor->ne[1] != w.a->ne[1]) {272 throw std::runtime_error("tensor '" + name + "' has incorrect shape (hint: maybe wrong base model?)");273 }274 } else {275 if (model_tensor->ne[0] != w.a->ne[0] || model_tensor->ne[1] != w.b->ne[1]) {276 throw std::runtime_error("tensor '" + name + "' has incorrect shape (hint: maybe wrong base model?)");277 }278 if (w.a->ne[1] != w.b->ne[0]) {279 throw std::runtime_error("lora_a tensor is not transposed (hint: adapter from \"finetune\" example is no longer supported)");280 }281 }282 283 // save tensor to adapter284 struct ggml_tensor * tensor_a = ggml_dup_tensor(dev_ctx, w.a);285 struct ggml_tensor * tensor_b = ggml_dup_tensor(dev_ctx, w.b);286 ggml_set_name(tensor_a, w.a->name);287 ggml_set_name(tensor_b, w.b->name);288 adapter.ab_map[name] = llama_adapter_lora_weight(tensor_a, tensor_b);289 }290 291 // allocate tensors / buffers and zero292 {293 adapter.ctxs.reserve(ctx_map.size());294 adapter.bufs.reserve(ctx_map.size());295 for (auto & it : ctx_map) {296 ggml_backend_buffer_type_t buft = it.first;297 ggml_context * ctx_dev = it.second;298 ggml_backend_buffer_ptr buf { ggml_backend_alloc_ctx_tensors_from_buft(ctx_dev, buft) };299 if (!buf) {300 throw std::runtime_error("failed to allocate buffer for lora adapter\n");301 }302 LLAMA_LOG_INFO("%s: %10s LoRA buffer size = %8.2f MiB\n", __func__, ggml_backend_buffer_name(buf.get()), ggml_backend_buffer_get_size(buf.get())/1024.0/1024.0);303 adapter.bufs.emplace_back(std::move(buf));304 }305 }306 307 // set tensor data308 {309 llama_file gguf_file(path_lora, "rb");310 std::vector<uint8_t> read_buf;311 auto set_tensor = [&](struct ggml_tensor * orig, struct ggml_tensor * dev) {312 size_t offs = gguf_get_data_offset(ctx_gguf.get()) + gguf_get_tensor_offset(ctx_gguf.get(), gguf_find_tensor(ctx_gguf.get(), orig->name));313 size_t size = ggml_nbytes(orig);314 read_buf.resize(size);315 gguf_file.seek(offs, SEEK_SET);316 gguf_file.read_raw(read_buf.data(), size);317 ggml_backend_tensor_set(dev, read_buf.data(), 0, size);318 };319 for (auto & it : adapter.ab_map) {320 auto orig = ab_map[it.first];321 auto dev = it.second;322 set_tensor(orig.a, dev.a);323 set_tensor(orig.b, dev.b);324 }325 }326 327 LLAMA_LOG_INFO("%s: loaded %zu tensors from lora file\n", __func__, adapter.ab_map.size()*2);328}329 330struct llama_adapter_lora * llama_adapter_lora_init(struct llama_model * model, const char * path_lora) {331 struct llama_adapter_lora * adapter = new llama_adapter_lora();332 333 try {334 llama_adapter_lora_init_impl(*model, path_lora, *adapter);335 return adapter;336 } catch (const std::exception & err) {337 LLAMA_LOG_ERROR("%s: failed to apply lora adapter: %s\n", __func__, err.what());338 339 delete adapter;340 }341 342 return nullptr;343}344 345void llama_adapter_lora_free(struct llama_adapter_lora * adapter) {346 delete adapter;347}348 