gvisor.dev/gvisor@v0.0.0-20240520182842-f9d4d51c7e0f/test/perf/linux/poll_benchmark.cc (about)

     1  // Copyright 2023 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  #include <sys/poll.h>
    16  
    17  #include <cstdint>
    18  #include <utility>
    19  #include <vector>
    20  
    21  #include "gmock/gmock.h"
    22  #include "gtest/gtest.h"
    23  #include "benchmark/benchmark.h"
    24  #include "test/util/eventfd_util.h"
    25  #include "test/util/file_descriptor.h"
    26  #include "test/util/posix_error.h"
    27  #include "test/util/test_util.h"
    28  
    29  namespace gvisor {
    30  namespace testing {
    31  
    32  namespace {
    33  
    34  void Setup(int count, std::vector<FileDescriptor>& event_fds,
    35             std::vector<pollfd>& poll_fds) {
    36    for (int i = 0; i < count; ++i) {
    37      FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(NewEventFD());
    38      poll_fds.push_back(pollfd{.fd = fd.get(), .events = POLLIN});
    39      event_fds.push_back(std::move(fd));
    40    }
    41  }
    42  
    43  void BM_PollTimeout(benchmark::State& state) {
    44    constexpr int kFDsPerPoll = 3;
    45    std::vector<FileDescriptor> event_fds;
    46    std::vector<pollfd> poll_fds;
    47    ASSERT_NO_FATAL_FAILURE(Setup(kFDsPerPoll, event_fds, poll_fds));
    48  
    49    const int timeout_ms = state.range(0);
    50    for (auto _ : state) {
    51      EXPECT_EQ(poll(poll_fds.data(), poll_fds.size(), timeout_ms), 0);
    52    }
    53  }
    54  
    55  BENCHMARK(BM_PollTimeout)->Range(/*start=*/0, /*limit=*/8);
    56  
    57  void BM_PollAllEvents(benchmark::State& state) {
    58    const int fds_per_poll = state.range(0);
    59    std::vector<FileDescriptor> event_fds;
    60    std::vector<pollfd> poll_fds;
    61    ASSERT_NO_FATAL_FAILURE(Setup(fds_per_poll, event_fds, poll_fds));
    62  
    63    constexpr uint64_t kEventVal = 5;
    64    for (const auto& eventfd : event_fds) {
    65      ASSERT_THAT(WriteFd(eventfd.get(), &kEventVal, sizeof(kEventVal)),
    66                  SyscallSucceedsWithValue(sizeof(kEventVal)));
    67    }
    68  
    69    constexpr int kTimeoutMs = 0;
    70    for (auto _ : state) {
    71      EXPECT_EQ(poll(poll_fds.data(), poll_fds.size(), kTimeoutMs), fds_per_poll);
    72    }
    73  }
    74  
    75  BENCHMARK(BM_PollAllEvents)->Range(/*start=*/2, /*limit=*/1024);
    76  
    77  }  // namespace
    78  
    79  }  // namespace testing
    80  }  // namespace gvisor