add map examples

.github/workflows/unit-test.yml

@@ -25,6 +25,7 @@ jobs:
     - name: Run example
       run: |
         ./build/vm-llvm-example
+        ./build/maps-example
 
     - name: Run tests
       run: |

codecov.yaml

@@ -1,5 +1,7 @@
 ignore:
   - "build"
+  - "test"
+  - "example"
 
 coverage:
   status:
@@ -15,3 +17,4 @@ coverage:
         target: auto
         base: auto
         only_pulls: false
+        threshold: 25%

example/CMakeLists.txt

@@ -5,3 +5,9 @@ bpftime_add_executable(vm-llvm-example
 add_dependencies(vm-llvm-example llvmbpf_vm spdlog::spdlog)
 target_link_libraries(vm-llvm-example llvmbpf_vm)
 
+bpftime_add_executable(maps-example
+    ./maps.cpp
+)
+
+add_dependencies(maps-example llvmbpf_vm spdlog::spdlog)
+target_link_libraries(maps-example llvmbpf_vm)

example/basic.cpp

@@ -8,6 +8,7 @@
 #include <stdio.h>
 #include <stdbool.h>
 #include <inttypes.h>
+#include <cassert>
 #include "llvmbpf.hpp"
 
 using namespace bpftime;
@@ -71,7 +72,7 @@ const unsigned char bpf_function_call_print[] =
 	"\xb7\x00\x00\x00\x00\x00\x00\x00"
 	"\x95\x00\x00\x00\x00\x00\x00\x00";
 
-void run_ebpf_prog(const void *code, size_t code_len)
+uint64_t run_ebpf_prog(const void *code, size_t code_len)
 {
 	uint64_t res = 0;
 	llvmbpf_vm vm;
@@ -96,13 +97,16 @@ void run_ebpf_prog(const void *code, size_t code_len)
 		exit(1);
 	}
 	printf("res = %" PRIu64 "\n", res);
+	return res;
 }
 
 int main(int argc, char *argv[])
 {
-	run_ebpf_prog(bpf_add_mem_64_bit, sizeof(bpf_add_mem_64_bit));
-	run_ebpf_prog(bpf_mul_64_bit, sizeof(bpf_mul_64_bit));
+	assert(run_ebpf_prog(bpf_add_mem_64_bit, sizeof(bpf_add_mem_64_bit)) ==
+	       3433728102);
+	assert(run_ebpf_prog(bpf_mul_64_bit, sizeof(bpf_mul_64_bit)) == 2);
 	// here we use string for the code
-	run_ebpf_prog(bpf_function_call_print, sizeof(bpf_function_call_print) - 1);
+	assert(run_ebpf_prog(bpf_function_call_print,
+			     sizeof(bpf_function_call_print) - 1) == 0);
 	return 0;
 }

example/maps.cpp

@@ -0,0 +1,131 @@
+#include <cstdint>
+#include <iostream>
+#include <ostream>
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <inttypes.h>
+#include <cassert>
+#include "llvmbpf.hpp"
+
+using namespace bpftime;
+const unsigned char xdp_counter_bytecode[] = "\x79\x16\x00\x00\x00\x00\x00\x00"
+					     "\x79\x17\x08\x00\x00\x00\x00\x00"
+					     "\xb7\x01\x00\x00\x00\x00\x00\x00"
+					     "\x63\x1a\xfc\xff\x00\x00\x00\x00"
+					     "\xbf\xa2\x00\x00\x00\x00\x00\x00"
+					     "\x07\x02\x00\x00\xfc\xff\xff\xff"
+					     "\x18\x11\x00\x00\x05\x00\x00\x00"
+					     "\x00\x00\x00\x00\x00\x00\x00\x00"
+					     "\x85\x00\x00\x00\x01\x00\x00\x00"
+					     "\xbf\x01\x00\x00\x00\x00\x00\x00"
+					     "\xb7\x00\x00\x00\x02\x00\x00\x00"
+					     "\x15\x01\x18\x00\x00\x00\x00\x00"
+					     "\x61\x11\x00\x00\x00\x00\x00\x00"
+					     "\x55\x01\x16\x00\x00\x00\x00\x00"
+					     "\x18\x21\x00\x00\x06\x00\x00\x00"
+					     "\x00\x00\x00\x00\x00\x00\x00\x00"
+					     "\x79\x12\x00\x00\x00\x00\x00\x00"
+					     "\x07\x02\x00\x00\x01\x00\x00\x00"
+					     "\x7b\x21\x00\x00\x00\x00\x00\x00"
+					     "\xb7\x00\x00\x00\x01\x00\x00\x00"
+					     "\xbf\x61\x00\x00\x00\x00\x00\x00"
+					     "\x07\x01\x00\x00\x0e\x00\x00\x00"
+					     "\x2d\x71\x0d\x00\x00\x00\x00\x00"
+					     "\x69\x61\x00\x00\x00\x00\x00\x00"
+					     "\x69\x62\x06\x00\x00\x00\x00\x00"
+					     "\x6b\x26\x00\x00\x00\x00\x00\x00"
+					     "\x69\x62\x08\x00\x00\x00\x00\x00"
+					     "\x69\x63\x02\x00\x00\x00\x00\x00"
+					     "\x6b\x36\x08\x00\x00\x00\x00\x00"
+					     "\x6b\x26\x02\x00\x00\x00\x00\x00"
+					     "\x69\x62\x0a\x00\x00\x00\x00\x00"
+					     "\x69\x63\x04\x00\x00\x00\x00\x00"
+					     "\x6b\x36\x0a\x00\x00\x00\x00\x00"
+					     "\x6b\x16\x06\x00\x00\x00\x00\x00"
+					     "\x6b\x26\x04\x00\x00\x00\x00\x00"
+					     "\xb7\x00\x00\x00\x03\x00\x00\x00"
+					     "\x95\x00\x00\x00\x00\x00\x00\x00";
+
+uint8_t bpf_mem[] = { 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88 };
+
+uint32_t ctl_array[2] = { 0, 0 };
+uint64_t cntrs_array[2] = { 0, 0 };
+
+void *bpf_map_lookup_elem(uint64_t map_fd, void *key)
+{
+	std::cout << "bpf_map_lookup_elem " << map_fd << std::endl;
+	if (map_fd == 5) {
+		return &ctl_array[*(uint32_t *)key];
+	} else if (map_fd == 6) {
+		return &cntrs_array[*(uint32_t *)key];
+	} else {
+		return nullptr;
+	}
+	return 0;
+}
+
+uint64_t map_by_fd(uint32_t fd)
+{
+	std::cout << "map_by_fd " << fd << std::endl;
+	return fd;
+}
+
+uint64_t map_val(uint64_t val)
+{
+	std::cout << "map_val " << val << std::endl;
+	if (val == 5) {
+		return (uint64_t)(void *)ctl_array;
+	} else if (val == 6) {
+		return (uint64_t)(void *)cntrs_array;
+	} else {
+		return 0;
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	auto code = xdp_counter_bytecode;
+	size_t code_len = sizeof(xdp_counter_bytecode) - 1;
+	uint64_t res = 0;
+	llvmbpf_vm vm;
+	std::cout << "running ebpf prog, code len: " << code_len << std::endl;
+
+	res = vm.load_code(code, code_len);
+	if (res) {
+		std::cout << vm.get_error_message() << std::endl;
+		exit(1);
+	}
+	vm.register_external_function(1, "bpf_map_lookup_elem",
+				      (void *)bpf_map_lookup_elem);
+	// set the lddw helpers for accessing maps
+	vm.set_lddw_helpers(map_by_fd, nullptr, map_val, nullptr, nullptr);
+	auto func = vm.compile();
+	if (!func) {
+		std::cout << vm.get_error_message() << std::endl;
+		exit(1);
+	}
+	// Map value (counter) should be 0
+	std::cout << "cntrs_array[0] = " << cntrs_array[0] << std::endl;
+	int err = vm.exec(&bpf_mem, sizeof(bpf_mem), res);
+	assert(err == 0 && cntrs_array[0] == 1);
+	std::cout << "\nreturn value = " << res << std::endl;
+	// counter should be 1
+	std::cout << "cntrs_array[0] = " << cntrs_array[0] << std::endl;
+
+	err = vm.exec(&bpf_mem, sizeof(bpf_mem), res);
+	assert(err == 0 && cntrs_array[0] == 2);
+	std::cout << "\nreturn value = " << res << std::endl;
+	// counter should be 2
+	std::cout << "cntrs_array[0] = " << cntrs_array[0] << std::endl;
+
+	// Change the value of the control array can change the return value
+	ctl_array[0] = 1;
+	err = vm.exec(&bpf_mem, sizeof(bpf_mem), res);
+	assert(err == 0);
+	std::cout << "\nreturn value = " << res << std::endl;
+	return 0;
+}

src/compiler.cpp

@@ -608,7 +608,8 @@
 						std::to_string(size) +
 						") or mode (" +
 						std::to_string(mode) +
-						") for non-standard load operations",
+						") for non-standard load operations" +
+						" at pc " + std::to_string(pc),
 					llvm::inconvertibleErrorCode());
 			}
 			if (pc + 1 >= insts.size()) {
@@ -619,8 +620,8 @@
 					llvm::inconvertibleErrorCode());
 			}
 			const auto &nextinst = insts[pc + 1];
-			if (nextinst.opcode || nextinst.dst ||
-			    nextinst.src || nextinst.offset) {
+			if (nextinst.opcode || nextinst.dst || nextinst.src ||
+			    nextinst.offset) {
 				return llvm::make_error<llvm::StringError>(
 					"Loaded LDDW at pc=" +
 						std::to_string(pc) +
@@ -677,7 +678,9 @@
 					if (!vm.map_val) {
 						return llvm::make_error<
 							llvm::StringError>(
-							"map_val is not provided, unable to compile",
+							"map_val is not provided, unable to compile at pc " +
+								std::to_string(
+									pc),
 							llvm::inconvertibleErrorCode());
 					}
 					builder.CreateStore(
@@ -688,7 +691,6 @@
 				} else {
 					SPDLOG_DEBUG(
 						"map_val is required to be evaluated at runtime, emitting calling instructions");
-
 					if (auto itrMapVal = lddwHelper.find(
 						    LDDW_HELPER_MAP_VAL);
 					    itrMapVal != lddwHelper.end()) {
@@ -708,7 +710,9 @@
 					} else {
 						return llvm::make_error<
 							llvm::StringError>(
-							"Using lddw helper 2, which requires map_val to be defined.",
+							"Using lddw helper 2, which requires map_val to be defined at pc " +
+								std::to_string(
+									pc),
 							llvm::inconvertibleErrorCode());
 					}
 				}
@@ -720,7 +724,8 @@
 				if (!vm.var_addr) {
 					return llvm::make_error<
 						llvm::StringError>(
-						"var_addr is not provided, unable to compile",
+						"var_addr is not provided, unable to compile at pc " +
+							std::to_string(pc),
 						llvm::inconvertibleErrorCode());
 				}
 				builder.CreateStore(
@@ -733,7 +738,8 @@
 				if (!vm.code_addr) {
 					return llvm::make_error<
 						llvm::StringError>(
-						"code_addr is not provided, unable to compile",
+						"code_addr is not provided, unable to compile at pc " +
+							std::to_string(pc),
 						llvm::inconvertibleErrorCode());
 				}
 				builder.CreateStore(
@@ -786,7 +792,9 @@
 					} else {
 						return llvm::make_error<
 							llvm::StringError>(
-							"map_val is not provided, unable to compile",
+							"map_val is not provided, unable to compile at pc " +
+								std::to_string(
+									pc),
 							llvm::inconvertibleErrorCode());
 					}
 
@@ -812,7 +820,9 @@
 					} else {
 						return llvm::make_error<
 							llvm::StringError>(
-							"Using lddw helper 6, which requires map_val",
+							"Using lddw helper 6 at pc " +
+								std::to_string(
+									pc),
 							llvm::inconvertibleErrorCode());
 					}
 				}
@@ -1056,7 +1066,8 @@
 					builder, &regs[0],
 					llvm::AtomicRMWInst::BinOp::Add, inst,
 					inst.opcode == EBPF_ATOMIC_OPCODE_64,
-					(inst.imm & EBPF_ATOMIC_OP_FETCH) == EBPF_ATOMIC_OP_FETCH);
+					(inst.imm & EBPF_ATOMIC_OP_FETCH) ==
+						EBPF_ATOMIC_OP_FETCH);
 				break;
 			}
 
@@ -1066,7 +1077,8 @@
 					builder, &regs[0],
 					llvm::AtomicRMWInst::BinOp::And, inst,
 					inst.opcode == EBPF_ATOMIC_OPCODE_64,
-					(inst.imm & EBPF_ATOMIC_OP_FETCH) == EBPF_ATOMIC_OP_FETCH);
+					(inst.imm & EBPF_ATOMIC_OP_FETCH) ==
+						EBPF_ATOMIC_OP_FETCH);
 				break;
 			}
 
@@ -1076,7 +1088,8 @@
 					builder, &regs[0],
 					llvm::AtomicRMWInst::BinOp::Or, inst,
 					inst.opcode == EBPF_ATOMIC_OPCODE_64,
-					(inst.imm & EBPF_ATOMIC_OP_FETCH) == EBPF_ATOMIC_OP_FETCH);
+					(inst.imm & EBPF_ATOMIC_OP_FETCH) ==
+						EBPF_ATOMIC_OP_FETCH);
 				break;
 			}
 			case EBPF_ATOMIC_XOR:
@@ -1085,7 +1098,8 @@
 					builder, &regs[0],
 					llvm::AtomicRMWInst::BinOp::Xor, inst,
 					inst.opcode == EBPF_ATOMIC_OPCODE_64,
-					(inst.imm & EBPF_ATOMIC_OP_FETCH) == EBPF_ATOMIC_OP_FETCH);
+					(inst.imm & EBPF_ATOMIC_OP_FETCH) ==
+						EBPF_ATOMIC_OP_FETCH);
 				break;
 			}
 			case EBPF_ATOMIC_OP_XCHG: {
@@ -1097,7 +1111,8 @@
 				break;
 			}
 			case EBPF_ATOMIC_OP_CMPXCHG: {
-				bool is64 = inst.opcode == EBPF_ATOMIC_OPCODE_64;
+				bool is64 =
+					inst.opcode == EBPF_ATOMIC_OPCODE_64;
 				auto vPtr = builder.CreateGEP(
 					builder.getInt8Ty(),
 					builder.CreateLoad(builder.getPtrTy(),
@@ -1138,7 +1153,8 @@
 		default:
 			return llvm::make_error<llvm::StringError>(
 				"Unsupported or illegal opcode: " +
-					std::to_string(inst.opcode),
+					std::to_string(inst.opcode) +
+					" at pc " + std::to_string(pc),
 				llvm::inconvertibleErrorCode());
 		}
 	}