// Copyright 2020 The gVisor Authors. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. #include <signal.h> #include <string.h> #include "gtest/gtest.h" #include "benchmark/benchmark.h" #include "test/util/logging.h" #include "test/util/test_util.h" namespace gvisor { namespace testing { namespace { void FixupHandler(int sig, siginfo_t* si, void* void_ctx) { static unsigned int dataval = 0; // Skip the offending instruction. ucontext_t* ctx = reinterpret_cast<ucontext_t*>(void_ctx); ctx->uc_mcontext.gregs[REG_RAX] = reinterpret_cast<greg_t>(&dataval); } void BM_FaultSignalFixup(benchmark::State& state) { // Set up the signal handler. struct sigaction sa = {}; sigemptyset(&sa.sa_mask); sa.sa_sigaction = FixupHandler; sa.sa_flags = SA_SIGINFO; TEST_CHECK(sigaction(SIGSEGV, &sa, nullptr) == 0); // Fault, fault, fault. for (auto _ : state) { // Trigger the segfault. asm volatile( "movq $0, %%rax\n" "movq $0x77777777, (%%rax)\n" : : : "rax"); } } BENCHMARK(BM_FaultSignalFixup)->UseRealTime(); } // namespace } // namespace testing } // namespace gvisor