Add: invoke TVM through pipe

python/cpp_plugin/gen_ansor_so.py

@@ -1,12 +1,13 @@
+import os
+import sys
+import json
 from contextlib import redirect_stdout
 import time
+import logging
 
 import numpy as np
 import tvm
 from tvm import te, tir, auto_scheduler, topi
-import os
-import json
-import logging
 
 USE_CACHE = True
 logging.basicConfig()
@@ -16,7 +17,7 @@ logger.setLevel(logging.INFO)
 
 def gen_ansor_so(input_tensors, input_dtypes, output_tensor, output_dtype,
                  tvm_code, func_name, nnet_expression: str,
-                 nnet_simplified_expression: str, hash_code=None):
+                 nnet_simplified_expression: str, hash_code: str = None):
     assert len(input_tensors) == len(input_dtypes)
 
     logger.debug(f'Work on hash {hash_code}')
@@ -117,3 +118,14 @@ def gen_ansor_so(input_tensors, input_dtypes, output_tensor, output_dtype,
             }, ensure_ascii=False, indent=2))
 
     return so_fn, conv_time
+
+# Read arguments from pipe, which is redirected to stdin.
+# Write generated library path to pipe.
+
+
+def pipe_gen(fd: int):
+    args = json.load(sys.stdin)  # read from pipe
+    # print(args, f'fd={fd}')
+    ret = gen_ansor_so(**args)
+    with os.fdopen(fd, 'w') as f:
+        print(ret[0], file=f, end='')  # write to pipe

src/kernels/cuda/membound_tvm_packed_function.cc

@@ -8,6 +8,12 @@
 #include "operators/pooling.h"
 #include "tvm/runtime/module.h"
 #include "tvm/runtime/packed_func.h"
+#include <nlohmann/json.hpp>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+using json = nlohmann::json;
 
 namespace py = pybind11;
 
@@ -124,7 +130,8 @@ class MemboundTVMPackedFunction : public Kernel {
         return std::dynamic_pointer_cast<PerfRecordObj>(ret);
     }
 
-    /// @brief
+    /// @brief Invoke TVM with pybind11. This approach is deprecated since it
+    /// ruins the python global scope and somehow breaks the cuBLAS runtime.
     /// @param inDims
     /// @param inDTypes
     /// @param outDims
@@ -137,7 +144,7 @@ class MemboundTVMPackedFunction : public Kernel {
     /// @param hashCode (optional) Hash code of the input expression for kernel
     /// cache.
     /// @return
-    std::string getAnsorDLL(const std::vector<std::vector<int>> &inDims,
+    std::string getAnsorDLLPybind11(const std::vector<std::vector<int>> &inDims,
                                     const std::vector<std::string> &inDTypes,
                                     const std::vector<int> &outDims,
                                     const std::string &outDType,
@@ -171,6 +178,95 @@ class MemboundTVMPackedFunction : public Kernel {
         return dllPath;
     }
 
+    std::string serializeTVMArgs(const std::vector<std::vector<int>> &inDims,
+                                 const std::vector<std::string> &inDTypes,
+                                 const std::vector<int> &outDims,
+                                 const std::string &outDType,
+                                 const std::string &lambda,
+                                 const std::string &funcName,
+                                 const std::string &nnetExprString,
+                                 const std::string &nnetSimplifiedExprString,
+                                 const HashType hashCode) const {
+        json j;
+        // Consistant with python API interface
+        j["input_tensors"] = inDims;
+        j["input_dtypes"] = inDTypes;
+        j["output_tensor"] = outDims;
+        j["output_dtype"] = outDType;
+        j["tvm_code"] = lambda;
+        j["func_name"] = funcName;
+        j["nnet_expression"] = nnetExprString;
+        j["nnet_simplified_expression"] = nnetSimplifiedExprString;
+        j["hash_code"] = std::to_string(hashCode);
+        return j.dump();
+    }
+
+    std::string getAnsorDLL(const std::vector<std::vector<int>> &inDims,
+                            const std::vector<std::string> &inDTypes,
+                            const std::vector<int> &outDims,
+                            const std::string &outDType,
+                            const std::string &lambda,
+                            const std::string &funcName,
+                            const std::string &nnetExprString,
+                            const std::string &nnetSimplifiedExprString,
+                            const HashType hashCode) const {
+        int fdP2C[2], fdC2P[2];
+        for (auto fd : {fdP2C, fdC2P}) {
+            int status = pipe(fd);
+            IT_ASSERT(status == 0, "pipe failed");
+        }
+        pid_t pid = fork();
+        IT_ASSERT(pid >= 0, "fork failed");
+        if (pid == 0) { // Child process
+            close(fdP2C[1]);
+            close(fdC2P[0]);
+
+            dup2(fdP2C[0], STDIN_FILENO);
+            close(fdP2C[0]);
+
+            string cmd =
+                "from cpp_plugin.gen_ansor_so import pipe_gen; pipe_gen(+" +
+                std::to_string(fdC2P[1]) + ")";
+            const char *const argv[] = {"python3", "-c", cmd.data(), NULL};
+            execvp("python3", const_cast<char *const *>(argv));
+        } else { // Parent process
+            close(fdP2C[0]);
+            close(fdC2P[1]);
+
+            // Write to pipe
+            string serializedArgs = serializeTVMArgs(
+                inDims, inDTypes, outDims, outDType, lambda, funcName,
+                nnetExprString, nnetSimplifiedExprString, hashCode);
+            int status = -1;
+            status =
+                write(fdP2C[1], serializedArgs.data(), serializedArgs.size());
+            IT_ASSERT(status == serializedArgs.size(),
+                      "Failed to write to pipe");
+            close(fdP2C[1]);
+
+            // Wait for TVM
+            waitpid(pid, &status, 0);
+            IT_ASSERT(WIFEXITED(status), "TVM process was terminated");
+            const int es = WEXITSTATUS(status);
+            IT_ASSERT(es == 0,
+                      "TVM process exit with code " + std::to_string(es));
+
+            // Read from pipe
+            FILE *stream;
+            int c;
+            stream = fdopen(fdC2P[0], "r");
+            char buf_read[257] = {0};
+            status = std::fscanf(stream, "%256c", buf_read);
+            IT_ASSERT(status == 1, "Failed to read from pipe");
+            IT_ASSERT(buf_read[256] == 0, "Pipe buffer overflow");
+            fclose(stream);
+            close(fdC2P[0]);
+            return buf_read;
+        }
+        IT_ASSERT(false, "Should not reach here");
+        return "";
+    }
+
     tvm::runtime::PackedFunc getPackedFunction(string path,
                                                string functionName) const {
         tvm::runtime::Module mod = tvm::runtime::Module::LoadFromFile(path);