Adding KV to Prefill IO (#9466)

Kush Rastogi · facebook-github-bot · commit 03bd85af1b72 · 2025-03-20T15:47:35.000-07:00
Summary: Pull Request resolved: #9466 Differential Revision: D71567692
diff --git a/examples/qualcomm/oss_scripts/llama/qnn_llama_runner.cpp b/examples/qualcomm/oss_scripts/llama/qnn_llama_runner.cpp
@@ -76,7 +76,11 @@ int main(int argc, char** argv) {
   std::vector<char> buf;
   buf.reserve(5 * FLAGS_seq_len); // assume each token is around 5 char
   std::ofstream fout(FLAGS_output_path.c_str());
-  auto callback = [&](const std::string& piece) {
+
+  int32_t num_total_tokens = 0;
+
+  auto callback = [&](const std::string& piece, int32_t tokens_generated) {
+    num_total_tokens += tokens_generated;
     for (const char c : piece) {
       buf.push_back(c);
     }
@@ -85,6 +89,7 @@ int main(int argc, char** argv) {
   for (int i = 0; i < FLAGS_num_iters; i++) {
     runner.generate(
         FLAGS_seq_len,
+        num_total_tokens,
         FLAGS_prompt.c_str(),
         FLAGS_system_prompt.c_str(),
         callback);
diff --git a/examples/qualcomm/oss_scripts/llama/runner/io_manager.cpp b/examples/qualcomm/oss_scripts/llama/runner/io_manager.cpp
@@ -494,6 +494,45 @@ void ShiftPointerIoMgr::prepare_prefill_io(
   }
 }
 
+void ShiftPointerIoMgr::update_kv_to_prefill_io(
+    int64_t pos,
+    std::vector<std::vector<executorch::aten::Tensor>>& output_tensors) {
+  // update v_cache
+  std::vector<std::unique_ptr<executorch::aten::TensorImpl>>& v_cache_in =
+      v_cache_in_[prefill_forward_name_];
+  std::vector<std::unique_ptr<executorch::aten::TensorImpl>>& v_cache_out =
+      v_cache_out_[prefill_forward_name_];
+  for (int i = 0, v_cache_stride = head_dim_ * pos; i < v_cache_in.size();
+       i++) {
+    v_cache_in[i]->set_data(
+        v_cache_in[i]->mutable_data<uint8_t>() + v_cache_stride);
+    v_cache_out[i]->set_data(
+        v_cache_out[i]->mutable_data<uint8_t>() + v_cache_stride);
+  }
+
+  // update k_cache
+  std::vector<std::unique_ptr<executorch::aten::TensorImpl>>& k_cache_in =
+      k_cache_in_[prefill_forward_name_];
+  std::vector<std::unique_ptr<executorch::aten::TensorImpl>>& k_cache_out =
+      k_cache_out_[prefill_forward_name_];
+
+    for (int i = 0, k_cache_stride = pos * sizeof(uint8_t); i < k_cache_in_.size();
+       i++) {
+    k_cache_in[i]->set_data(
+        k_cache_in[i]->mutable_data<uint8_t>() + k_cache_stride);
+    k_cache_out[i]->set_data(
+        k_cache_out[i]->mutable_data<uint8_t>() + k_cache_stride);
+  }
+
+  // Setting attention mask from context_len - prefill_ar_len - i to context_len
+  IO* ptr = static_cast<IO*>(data_ptr_.get());
+  for (int i = prefill_ar_len_; i < pos; i++) {
+    for (int j = 0; j < prefill_ar_len_; j++) {
+      ptr->prefill_attention_mask[j * context_len_ + context_len_ - prefill_ar_len_ - i] = 65535;
+    }
+  }
+}
+
 void ShiftPointerIoMgr::update_prefill_to_kv_io(
     int64_t cur_token,
     int64_t pos,
@@ -664,33 +703,32 @@ void ShiftPointerIoMgr::update_prefill_io(
 }
 
 void ShiftPointerIoMgr::fill_prefill_toks(
-    int64_t start_pos,
+      int64_t num_prev_tokens,
+      int64_t prompt_pos,
     std::vector<uint64_t>& prompt_tokens) {
   IO* ptr = static_cast<IO*>(get_mutable_ptr());
   for (int i = 0; i < prefill_ar_len_; i++) {
     if (!is_bert_) {
-      ptr->prefill_input_pos[i] = start_pos + i;
+      ptr->prefill_input_pos[i] = num_prev_tokens + prompt_pos + i;
     }
 
-    if (start_pos + i < prompt_tokens.size()) {
+    if (prompt_pos + i < prompt_tokens.size()) {
       // Support CPU 4-bit embedding, which requires int64 input.
       // However, for QNN embedding, only int32 input is needed.
       // Therefore, we need to cast to the correct type to write the data.
       if (use_int64_token_) {
-        ptr->prefill_input_toks[i] = prompt_tokens[start_pos + i];
+        ptr->prefill_input_toks[i] = prompt_tokens[prompt_pos + i];
       } else {
         int32_t* prefill_input_toks_ptr =
             reinterpret_cast<int32_t*>(ptr->prefill_input_toks.data());
         prefill_input_toks_ptr[i] =
-            static_cast<int32_t>(prompt_tokens[start_pos + i]);
+            static_cast<int32_t>(prompt_tokens[prompt_pos + i]);
       }
     }
-    if (start_pos >= prefill_ar_len_) {
-      for (int j = 0,
-               offset = i * context_len_ +
-               (context_len_ - prefill_ar_len_ - start_pos);
-           j < prefill_ar_len_;
-           ++j) {
+    if (num_prev_tokens + prompt_pos >= prefill_ar_len_) {
+      int64_t start_offset = i * context_len_ +
+          (context_len_ - num_prev_tokens - prompt_pos - prefill_ar_len_);
+      for (int j = 0, offset = start_offset; j < prefill_ar_len_; ++j) {
         ptr->prefill_attention_mask[offset + j] = 65535;
       }
     }
@@ -1305,6 +1343,12 @@ void SmartMaskIoMgr::prepare_prefill_io(
   }
 }
 
+void SmartMaskIoMgr::update_kv_to_prefill_io(
+    int64_t pos,
+    std::vector<std::vector<Tensor>>& output_tensors) {
+      //TODO: Fill In
+    }
+
 void SmartMaskIoMgr::update_prefill_to_kv_io(
     int64_t cur_token,
     int64_t pos,
@@ -1396,29 +1440,30 @@ void SmartMaskIoMgr::update_prefill_io(
 }
 
 void SmartMaskIoMgr::fill_prefill_toks(
-    int64_t start_pos,
+      int64_t num_prev_tokens,
+      int64_t prompt_pos,
     std::vector<uint64_t>& prompt_tokens) {
   IO* ptr = static_cast<IO*>(get_mutable_ptr());
   for (int i = 0; i < prefill_ar_len_; i++) {
     if (!is_bert_) {
-      ptr->prefill_input_pos[i] = start_pos + i;
+      ptr->prefill_input_pos[i] = prompt_pos + i;
     }
 
-    if (start_pos + i < prompt_tokens.size()) {
+    if (prompt_pos + i < prompt_tokens.size()) {
       // Support CPU 4-bit embedding, which requires int64 input.
       // However, for QNN embedding, only int32 input is needed.
       // Therefore, we need to cast to the correct type to write the data.
       if (use_int64_token_) {
-        ptr->prefill_input_toks[i] = prompt_tokens[start_pos + i];
+        ptr->prefill_input_toks[i] = prompt_tokens[prompt_pos + i];
       } else {
         int32_t* prefill_input_toks_ptr =
             reinterpret_cast<int32_t*>(ptr->prefill_input_toks);
         prefill_input_toks_ptr[i] =
-            static_cast<int32_t>(prompt_tokens[start_pos + i]);
+            static_cast<int32_t>(prompt_tokens[prompt_pos + i]);
       }
     }
-    if (start_pos >= prefill_ar_len_) {
-      for (int j = 0, offset = i * context_len_ + (start_pos - prefill_ar_len_);
+    if (prompt_pos >= prefill_ar_len_) {
+      for (int j = 0, offset = i * context_len_ + (prompt_pos - prefill_ar_len_);
            j < prefill_ar_len_;
            ++j) {
         ptr->prefill_attention_mask[offset + j] = 65535;
diff --git a/examples/qualcomm/oss_scripts/llama/runner/io_manager.h b/examples/qualcomm/oss_scripts/llama/runner/io_manager.h
@@ -48,9 +48,13 @@ class IoMgrBase {
           executorch::runtime::Result<executorch::runtime::MethodMeta>>&
           methods_meta) = 0;
   virtual void fill_prefill_toks(
-      int64_t start_pos,
+      int64_t num_prev_tokens,
+      int64_t prompt_pos,
       std::vector<uint64_t>& prompt_tokens) = 0;
   virtual void fill_kv_tok_mask(int64_t pos, int64_t cur_token) = 0;
+  virtual void update_kv_to_prefill_io(
+      int64_t pos,
+      std::vector<std::vector<executorch::aten::Tensor>>& output_tensors) = 0;
   virtual void update_prefill_to_kv_io(
       int64_t cur_token,
       int64_t pos,
@@ -118,9 +122,13 @@ class ShiftPointerIoMgr : public IoMgrBase {
           executorch::runtime::Result<executorch::runtime::MethodMeta>>&
           methods_meta) override;
   void fill_prefill_toks(
-      int64_t start_pos,
+      int64_t num_prev_tokens,
+      int64_t prompt_pos,
       std::vector<uint64_t>& prompt_tokens) override;
   void fill_kv_tok_mask(int64_t pos, int64_t cur_token) override;
+  void update_kv_to_prefill_io(
+      int64_t pos,
+      std::vector<std::vector<executorch::aten::Tensor>>& output_tensors) override;
   void update_prefill_to_kv_io(
       int64_t cur_token,
       int64_t pos,
@@ -226,9 +234,13 @@ class SmartMaskIoMgr : public IoMgrBase {
           executorch::runtime::Result<executorch::runtime::MethodMeta>>&
           methods_meta) override;
   void fill_prefill_toks(
-      int64_t start_pos,
+      int64_t num_prev_tokens,
+      int64_t prompt_pos,
       std::vector<uint64_t>& prompt_tokens) override;
   void fill_kv_tok_mask(int64_t pos, int64_t cur_token) override;
+  void update_kv_to_prefill_io(
+      int64_t pos,
+      std::vector<std::vector<executorch::aten::Tensor>>& output_tensors) override;
   void update_prefill_to_kv_io(
       int64_t cur_token,
       int64_t pos,
diff --git a/examples/qualcomm/oss_scripts/llama/runner/runner.cpp b/examples/qualcomm/oss_scripts/llama/runner/runner.cpp
@@ -276,9 +276,10 @@ void Runner::run_model_step(
 
 Error Runner::generate(
     int32_t seq_len,
+    int32_t num_prev_tokens,
     const std::string& prompt,
     const std::string& system_prompt,
-    std::function<void(const std::string&)> token_callback,
+    std::function<void(const std::string&, int32_t)> token_callback,
     std::function<void(const Stats&)> stats_callback) {
   std::unordered_map<std::string, std::vector<std::vector<Tensor>>>
       input_tensors, output_tensors;
@@ -327,14 +328,16 @@ Error Runner::generate(
       prompt_.append(
           "<|eot_id|><|start_header_id|>assistant<|end_header_id|>\n\n");
       if (token_callback) {
-        token_callback("<|begin_of_text|>");
+        token_callback("<|begin_of_text|>", 0);
       }
       break;
     default:
       ET_CHECK_MSG(false, "unsupported llama version");
       break;
   }
 
+  ET_LOG(Info, "Number of Previous Tokens Prefill + Decode: %d", num_prev_tokens);
+
   seq_len = (seq_len > 0 && seq_len <= context_len_) ? seq_len : context_len_;
   tokenizers::Result<std::vector<uint64_t>> encode_res =
       tokenizer_->encode(prompt_, n_bos_, 0);
@@ -349,7 +352,7 @@ Error Runner::generate(
 
   int64_t pos = 0, prev_token, cur_token = prompt_tokens[0];
   if (token_callback) {
-    token_callback(prompt_);
+      token_callback(prompt_, num_prompt_tokens);
   }
   auto prefill_execute = [&](const std::string& method_name) {
     int num_iters = 1 + ((num_prompt_tokens - 1) / prefill_ar_len_);
@@ -361,7 +364,7 @@ Error Runner::generate(
         num_iters);
 
     for (int i = 0; i < num_iters; i++) {
-      io_mgr_->fill_prefill_toks(pos, prompt_tokens);
+      io_mgr_->fill_prefill_toks(num_prev_tokens, pos, prompt_tokens);
       run_model_step(method_name, inputs[method_name]);
       io_mgr_->update_prefill_io(cur_token, pos, output_tensors[method_name]);
       pos += prefill_ar_len_;
@@ -377,10 +380,12 @@ Error Runner::generate(
     auto piece_res = tokenizer_->decode(prev_token, cur_token);
     ET_CHECK(piece_res.ok());
     if (token_callback) {
-      token_callback(piece_res.get().c_str());
+      ET_LOG(Info, "Prefill: %s", piece_res.get().c_str());
+      token_callback(piece_res.get().c_str(), 1);
     }
 
-    pos = num_prompt_tokens;
+    pos = num_prev_tokens + num_prompt_tokens;
+    ET_LOG(Info, "Pos: %ld, Prompt Tokens: %ld", pos, num_prompt_tokens);
     stats_.first_token_ms = time_in_ms();
     stats_.prompt_eval_end_ms = time_in_ms();
   };
@@ -394,9 +399,9 @@ Error Runner::generate(
 
       // hybrid mode will check these stats_ at prefill(prefill)
       if (eval_mode_ == EvalMode::kKVCached) {
-        if (pos == num_prompt_tokens) {
+        if (pos == num_prev_tokens + num_prompt_tokens) {
           stats_.first_token_ms = time_in_ms();
-        } else if (pos == num_prompt_tokens - 1) {
+        } else if (pos == num_prev_tokens + num_prompt_tokens - 1) {
           stats_.prompt_eval_end_ms = time_in_ms();
         }
       }
@@ -405,15 +410,15 @@ Error Runner::generate(
       cur_token = logitsToToken(logits_tensor, pos);
       stats_.aggregate_sampling_time_ms += time_in_ms() - sample_start_time_ms;
 
-      if (pos < num_prompt_tokens - 1) {
+      if (pos < num_prev_tokens + num_prompt_tokens - 1) {
         cur_token = prompt_tokens[pos + 1];
       }
       io_mgr_->update_kv_io(cur_token, ++pos, output_tensors[method_name]);
       auto piece_res = tokenizer_->decode(prev_token, cur_token);
       ET_CHECK(piece_res.ok());
 
       if (token_callback && pos >= num_prompt_tokens) {
-        token_callback(piece_res.get().c_str());
+        token_callback(piece_res.get().c_str(), 1);
       }
 
       if (pos >= num_prompt_tokens && eos_id_.count(cur_token) > 0) {
@@ -432,6 +437,7 @@ Error Runner::generate(
       io_mgr_->update_prefill_to_kv_io(
           cur_token, pos, output_tensors[kv_forward_name_]);
       kv_execute(kv_forward_name_);
+      io_mgr_->update_kv_to_prefill_io(pos, output_tensors[prefill_forward_name_]);
       break;
     default:
       ET_CHECK_MSG(false, "Unsupported eval mode");
@@ -448,9 +454,9 @@ Error Runner::generate(
   if (stats_callback) {
     stats_callback(stats_);
   }
-  io_mgr_->reset_io(
-      get_methods_meta(prefill_forward_name_),
-      get_methods_meta(kv_forward_name_));
+  // io_mgr_->reset_io(
+  //     get_methods_meta(prefill_forward_name_),
+  //     get_methods_meta(kv_forward_name_));
   prompt_.clear();
   return Error::Ok;
 }
diff --git a/examples/qualcomm/oss_scripts/llama/runner/runner.h b/examples/qualcomm/oss_scripts/llama/runner/runner.h
@@ -67,9 +67,10 @@ class Runner {
   executorch::runtime::Error load();
   executorch::runtime::Error generate(
       int32_t seq_len,
+      int32_t num_prev_tokens,
       const std::string& prompt,
       const std::string& system_prompt,
-      std::function<void(const std::string&)> token_callback = {},
+      std::function<void(const std::string&, int32_t)> token_callback = {},
       std::function<void(const Stats&)> stats_callback = {});
   void stop();
   std::vector<executorch::runtime::Result<executorch::runtime::MethodMeta>>
