[record & replay] Introduce a virtual base class for BCCWrapper.

src/stirling/benchmarks/bpf_map_ops_benchmark.cc

@@ -27,7 +27,7 @@
 #include "src/stirling/utils/proc_path_tools.h"
 
 using ::px::stirling::GetSelfPath;
-using ::px::stirling::bpf_tools::BCCWrapper;
+using ::px::stirling::bpf_tools::BCCWrapperImpl;
 using ::px::stirling::bpf_tools::BPFProbeAttachType;
 using ::px::stirling::bpf_tools::UProbeSpec;
 using ::px::stirling::bpf_tools::WrappedBCCMap;
@@ -50,7 +50,7 @@ NO_OPT_ATTR void BPFMapPopulateTrigger(int n) {
 }
 }
 
-void SetupCleanupProbe(BCCWrapper* bcc) {
+void SetupCleanupProbe(BCCWrapperImpl* bcc) {
  std::filesystem::path self_path = GetSelfPath().ValueOrDie();
  auto elf_reader_or_s = px::stirling::obj_tools::ElfReader::Create(self_path.string());
  PX_CHECK_OK(elf_reader_or_s.status());
@@ -75,7 +75,7 @@ void SetupCleanupProbe(BCCWrapper* bcc) {
  PX_CHECK_OK(bcc->AttachUProbe(uprobe));
 }
 
-void SetupPopulateProbe(BCCWrapper* bcc) {
+void SetupPopulateProbe(BCCWrapperImpl* bcc) {
  std::filesystem::path self_path = GetSelfPath().ValueOrDie();
  auto elf_reader_or_s = px::stirling::obj_tools::ElfReader::Create(self_path.string());
  PX_CHECK_OK(elf_reader_or_s.status());
@@ -102,7 +102,7 @@ void SetupPopulateProbe(BCCWrapper* bcc) {
 
 // NOLINTNEXTLINE : runtime/references.
 static void BM_userspace_update_remove(benchmark::State& state) {
- BCCWrapper bcc_wrapper;
+ BCCWrapperImpl bcc_wrapper;
  std::string_view kProgram = "BPF_HASH(map, int, int);";
  PX_CHECK_OK(bcc_wrapper.InitBPFProgram(kProgram));
  auto bpf_map = WrappedBCCMap<int, int>::Create(&bcc_wrapper, "map");
@@ -124,7 +124,7 @@ static void BM_userspace_update_remove(benchmark::State& state) {
 
 // NOLINTNEXTLINE : runtime/references.
 static void BM_bpf_triggered_update_remove(benchmark::State& state) {
- BCCWrapper bcc_wrapper;
+ BCCWrapperImpl bcc_wrapper;
  std::string_view kProgram = R"(
 #include <linux/ptrace.h>
 
@@ -192,7 +192,7 @@ int map_populate_uprobe(struct pt_regs* ctx) {
 
 // NOLINTNEXTLINE : runtime/references.
 static void BM_userspace_update_get_remove(benchmark::State& state) {
- BCCWrapper bcc_wrapper;
+ BCCWrapperImpl bcc_wrapper;
  std::string_view kProgram = "BPF_HASH(map, int, int);";
  PX_CHECK_OK(bcc_wrapper.InitBPFProgram(kProgram));
  auto bpf_map = WrappedBCCMap<int, int>::Create(&bcc_wrapper, "map");
@@ -217,7 +217,7 @@ static void BM_userspace_update_get_remove(benchmark::State& state) {
 
 // NOLINTNEXTLINE : runtime/references.
 static void BM_bpf_triggered_update_get_remove(benchmark::State& state) {
- BCCWrapper bcc_wrapper;
+ BCCWrapperImpl bcc_wrapper;
  std::string_view kProgram = R"(
 #include <linux/ptrace.h>
 

src/stirling/benchmarks/symbolization_benchmark.cc

@@ -24,7 +24,7 @@
 #include "src/stirling/obj_tools/address_converter.h"
 #include "src/stirling/obj_tools/elf_reader.h"
 
-using ::px::stirling::bpf_tools::BCCWrapper;
+using ::px::stirling::bpf_tools::BCCWrapperImpl;
 using ::px::stirling::bpf_tools::WrappedBCCArrayTable;
 using ::px::stirling::bpf_tools::WrappedBCCStackTable;
 using ::px::stirling::obj_tools::ElfReader;
@@ -64,7 +64,7 @@ const std::string_view kProgram = R"(
  }
 )";
 
-std::vector<uintptr_t> CollectStackTrace(BCCWrapper* bcc_wrapper,
+std::vector<uintptr_t> CollectStackTrace(BCCWrapperImpl* bcc_wrapper,
  const std::filesystem::path& self_path) {
  ::px::stirling::bpf_tools::UProbeSpec spec = {
  .binary_path = self_path.string(),
@@ -90,7 +90,7 @@ std::vector<uintptr_t> CollectStackTrace(BCCWrapper* bcc_wrapper,
 
 // NOLINTNEXTLINE : runtime/references.
 static void BM_elf_reader_symbolization(benchmark::State& state) {
- BCCWrapper bcc_wrapper;
+ BCCWrapperImpl bcc_wrapper;
  PX_ASSIGN_OR_EXIT(std::filesystem::path self_path, ::px::fs::ReadSymlink("/proc/self/exe"));
  std::vector<uintptr_t> addrs = CollectStackTrace(&bcc_wrapper, self_path);
  PX_ASSIGN_OR_EXIT(auto elf_reader,
@@ -112,7 +112,7 @@ static void BM_elf_reader_symbolization(benchmark::State& state) {
 
 // NOLINTNEXTLINE : runtime/references.
 static void BM_elf_reader_symbolization_indexed(benchmark::State& state) {
- BCCWrapper bcc_wrapper;
+ BCCWrapperImpl bcc_wrapper;
  PX_ASSIGN_OR_EXIT(std::filesystem::path self_path, ::px::fs::ReadSymlink("/proc/self/exe"));
  std::vector<uintptr_t> addrs = CollectStackTrace(&bcc_wrapper, self_path);
  PX_ASSIGN_OR_EXIT(auto elf_reader, ElfReader::Create(self_path.string()));
@@ -134,7 +134,7 @@ static void BM_elf_reader_symbolization_indexed(benchmark::State& state) {
 
 // NOLINTNEXTLINE : runtime/references.
 static void BM_bcc_symbolization(benchmark::State& state) {
- BCCWrapper bcc_wrapper;
+ BCCWrapperImpl bcc_wrapper;
  PX_ASSIGN_OR_EXIT(std::filesystem::path self_path, ::px::fs::ReadSymlink("/proc/self/exe"));
  std::vector<uintptr_t> addrs = CollectStackTrace(&bcc_wrapper, self_path);
  auto bcc_symbolizer = WrappedBCCStackTable::Create(&bcc_wrapper, "stack_traces");

src/stirling/bpf_tools/bcc_wrapper.cc

@@ -97,9 +97,9 @@ StatusOr<utils::TaskStructOffsets> BCCWrapper::ComputeTaskStructOffsets() {
  return task_struct_offsets_opt_.value();
 }
 
-Status BCCWrapper::InitBPFProgram(std::string_view bpf_program, std::vector<std::string> cflags,
- bool requires_linux_headers,
- bool always_infer_task_struct_offsets) {
+Status BCCWrapperImpl::InitBPFProgram(std::string_view bpf_program, std::vector<std::string> cflags,
+  bool requires_linux_headers,
+  bool always_infer_task_struct_offsets) {
  using utils::TaskStructOffsets;
 
  if (!IsRoot()) {
@@ -177,7 +177,7 @@ Status BCCWrapper::InitBPFProgram(std::string_view bpf_program, std::vector<std:
  return Status::OK();
 }
 
-Status BCCWrapper::AttachKProbe(const KProbeSpec& probe) {
+Status BCCWrapperImpl::AttachKProbe(const KProbeSpec& probe) {
  VLOG(1) << "Deploying kprobe: " << probe.ToString();
  DCHECK(probe.attach_type != BPFProbeAttachType::kReturnInsts);
 
@@ -197,7 +197,7 @@ Status BCCWrapper::AttachKProbe(const KProbeSpec& probe) {
  return Status::OK();
 }
 
-Status BCCWrapper::AttachTracepoint(const TracepointSpec& probe) {
+Status BCCWrapperImpl::AttachTracepoint(const TracepointSpec& probe) {
  VLOG(1) << "Deploying tracepoint: " << probe.ToString();
 
  PX_RETURN_IF_ERROR(bpf_.attach_tracepoint(probe.tracepoint, probe.probe_fn));
@@ -206,7 +206,7 @@ Status BCCWrapper::AttachTracepoint(const TracepointSpec& probe) {
  return Status::OK();
 }
 
-Status BCCWrapper::AttachUProbe(const UProbeSpec& probe) {
+Status BCCWrapperImpl::AttachUProbe(const UProbeSpec& probe) {
  VLOG(1) << "Deploying uprobe: " << probe.ToString();
  // TODO(oazizi): Natively support this attach type in BCCWrapper.
  DCHECK(probe.attach_type != BPFProbeAttachType::kReturnInsts);
@@ -227,7 +227,7 @@ Status BCCWrapper::AttachUProbe(const UProbeSpec& probe) {
  return Status::OK();
 }
 
-Status BCCWrapper::AttachSamplingProbe(const SamplingProbeSpec& probe) {
+Status BCCWrapperImpl::AttachSamplingProbe(const SamplingProbeSpec& probe) {
  constexpr uint64_t kNanosPerMilli = 1000 * 1000;
  const uint64_t sample_period = probe.period_millis * kNanosPerMilli;
  // A sampling probe is just a PerfEventProbe, where the perf event is a clock counter.
@@ -242,28 +242,28 @@ Status BCCWrapper::AttachSamplingProbe(const SamplingProbeSpec& probe) {
  return AttachPerfEvent(perf_event_spec);
 }
 
-Status BCCWrapper::AttachKProbes(const ArrayView<KProbeSpec>& probes) {
+Status BCCWrapperImpl::AttachKProbes(const ArrayView<KProbeSpec>& probes) {
  for (const KProbeSpec& p : probes) {
  PX_RETURN_IF_ERROR(AttachKProbe(p));
  }
  return Status::OK();
 }
 
-Status BCCWrapper::AttachTracepoints(const ArrayView<TracepointSpec>& probes) {
+Status BCCWrapperImpl::AttachTracepoints(const ArrayView<TracepointSpec>& probes) {
  for (const TracepointSpec& spec : probes) {
  PX_RETURN_IF_ERROR(AttachTracepoint(spec));
  }
  return Status::OK();
 }
 
-Status BCCWrapper::AttachUProbes(const ArrayView<UProbeSpec>& probes) {
+Status BCCWrapperImpl::AttachUProbes(const ArrayView<UProbeSpec>& probes) {
  for (const UProbeSpec& p : probes) {
  PX_RETURN_IF_ERROR(AttachUProbe(p));
  }
  return Status::OK();
 }
 
-Status BCCWrapper::AttachSamplingProbes(const ArrayView<SamplingProbeSpec>& probes) {
+Status BCCWrapperImpl::AttachSamplingProbes(const ArrayView<SamplingProbeSpec>& probes) {
  for (const SamplingProbeSpec& p : probes) {
  PX_RETURN_IF_ERROR(AttachSamplingProbe(p));
  }
@@ -273,7 +273,7 @@ Status BCCWrapper::AttachSamplingProbes(const ArrayView<SamplingProbeSpec>& prob
 // This will replace the XDP program previously-attached on the the same device.
 // Newer kernel allows attaching multiple XDP programs on the same device:
 // https://lwn.net/Articles/801478/
-Status BCCWrapper::AttachXDP(const std::string& dev_name, const std::string& fn_name) {
+Status BCCWrapperImpl::AttachXDP(const std::string& dev_name, const std::string& fn_name) {
  int fn_fd = -1;
  ebpf::StatusTuple load_status = bpf_.load_func(fn_name, BPF_PROG_TYPE_XDP, fn_fd);
 
@@ -293,15 +293,15 @@ Status BCCWrapper::AttachXDP(const std::string& dev_name, const std::string& fn_
 }
 
 // TODO(PL-1294): This can fail in rare cases. See the cited issue. Find the root cause.
-Status BCCWrapper::DetachKProbe(const KProbeSpec& probe) {
+Status BCCWrapperImpl::DetachKProbe(const KProbeSpec& probe) {
  VLOG(1) << "Detaching kprobe: " << probe.ToString();
  PX_RETURN_IF_ERROR(bpf_.detach_kprobe(GetKProbeTargetName(probe),
  static_cast<bpf_probe_attach_type>(probe.attach_type)));
  --num_attached_kprobes_;
  return Status::OK();
 }
 
-Status BCCWrapper::DetachUProbe(const UProbeSpec& probe) {
+Status BCCWrapperImpl::DetachUProbe(const UProbeSpec& probe) {
  VLOG(1) << "Detaching uprobe " << probe.ToString();
 
  if (fs::Exists(probe.binary_path)) {
@@ -313,7 +313,7 @@ Status BCCWrapper::DetachUProbe(const UProbeSpec& probe) {
  return Status::OK();
 }
 
-Status BCCWrapper::DetachTracepoint(const TracepointSpec& probe) {
+Status BCCWrapperImpl::DetachTracepoint(const TracepointSpec& probe) {
  VLOG(1) << "Detaching tracepoint " << probe.ToString();
 
  PX_RETURN_IF_ERROR(bpf_.detach_tracepoint(probe.tracepoint));
@@ -322,31 +322,31 @@ Status BCCWrapper::DetachTracepoint(const TracepointSpec& probe) {
  return Status::OK();
 }
 
-void BCCWrapper::DetachKProbes() {
+void BCCWrapperImpl::DetachKProbes() {
  for (const auto& p : kprobes_) {
  auto res = DetachKProbe(p);
  LOG_IF(ERROR, !res.ok()) << res.msg();
  }
  kprobes_.clear();
 }
 
-void BCCWrapper::DetachUProbes() {
+void BCCWrapperImpl::DetachUProbes() {
  for (const auto& p : uprobes_) {
  auto res = DetachUProbe(p);
  LOG_IF(ERROR, !res.ok()) << res.msg();
  }
  uprobes_.clear();
 }
 
-void BCCWrapper::DetachTracepoints() {
+void BCCWrapperImpl::DetachTracepoints() {
  for (const auto& t : tracepoints_) {
  auto res = DetachTracepoint(t);
  LOG_IF(ERROR, !res.ok()) << res.msg();
  }
  tracepoints_.clear();
 }
 
-Status BCCWrapper::OpenPerfBuffer(const PerfBufferSpec& perf_buffer) {
+Status BCCWrapperImpl::OpenPerfBuffer(const PerfBufferSpec& perf_buffer) {
  const int kPageSizeBytes = system::Config::GetInstance().PageSizeBytes();
  int num_pages = IntRoundUpDivide(perf_buffer.size_bytes, kPageSizeBytes);
 
@@ -364,29 +364,29 @@ Status BCCWrapper::OpenPerfBuffer(const PerfBufferSpec& perf_buffer) {
  return Status::OK();
 }
 
-Status BCCWrapper::OpenPerfBuffers(const ArrayView<PerfBufferSpec>& perf_buffers) {
+Status BCCWrapperImpl::OpenPerfBuffers(const ArrayView<PerfBufferSpec>& perf_buffers) {
  for (const PerfBufferSpec& p : perf_buffers) {
  PX_RETURN_IF_ERROR(OpenPerfBuffer(p));
  }
  return Status::OK();
 }
 
-Status BCCWrapper::ClosePerfBuffer(const PerfBufferSpec& perf_buffer) {
+Status BCCWrapperImpl::ClosePerfBuffer(const PerfBufferSpec& perf_buffer) {
  VLOG(1) << "Closing perf buffer: " << perf_buffer.name;
  PX_RETURN_IF_ERROR(bpf_.close_perf_buffer(std::string(perf_buffer.name)));
  --num_open_perf_buffers_;
  return Status::OK();
 }
 
-void BCCWrapper::ClosePerfBuffers() {
+void BCCWrapperImpl::ClosePerfBuffers() {
  for (const PerfBufferSpec& p : perf_buffers_) {
  auto res = ClosePerfBuffer(p);
  LOG_IF(ERROR, !res.ok()) << res.msg();
  }
  perf_buffers_.clear();
 }
 
-Status BCCWrapper::AttachPerfEvent(const PerfEventSpec& perf_event) {
+Status BCCWrapperImpl::AttachPerfEvent(const PerfEventSpec& perf_event) {
  VLOG(1) << absl::Substitute("Attaching perf event:\n type=$0\n probe_fn=$1",
  magic_enum::enum_name(perf_event.type), perf_event.probe_fn);
  PX_RETURN_IF_ERROR(bpf_.attach_perf_event(perf_event.type, perf_event.config,
@@ -397,58 +397,60 @@ Status BCCWrapper::AttachPerfEvent(const PerfEventSpec& perf_event) {
  return Status::OK();
 }
 
-Status BCCWrapper::AttachPerfEvents(const ArrayView<PerfEventSpec>& perf_events) {
+Status BCCWrapperImpl::AttachPerfEvents(const ArrayView<PerfEventSpec>& perf_events) {
  for (const PerfEventSpec& p : perf_events) {
  PX_RETURN_IF_ERROR(AttachPerfEvent(p));
  }
  return Status::OK();
 }
 
-Status BCCWrapper::DetachPerfEvent(const PerfEventSpec& perf_event) {
+Status BCCWrapperImpl::DetachPerfEvent(const PerfEventSpec& perf_event) {
  VLOG(1) << absl::Substitute("Detaching perf event:\n type=$0\n probe_fn=$1",
  magic_enum::enum_name(perf_event.type), perf_event.probe_fn);
  PX_RETURN_IF_ERROR(bpf_.detach_perf_event(perf_event.type, perf_event.config));
  --num_attached_perf_events_;
  return Status::OK();
 }
 
-void BCCWrapper::DetachPerfEvents() {
+void BCCWrapperImpl::DetachPerfEvents() {
  for (const PerfEventSpec& p : perf_events_) {
  auto res = DetachPerfEvent(p);
  LOG_IF(ERROR, !res.ok()) << res.msg();
  }
  perf_events_.clear();
 }
 
-std::string BCCWrapper::GetKProbeTargetName(const KProbeSpec& probe) {
+std::string BCCWrapperImpl::GetKProbeTargetName(const KProbeSpec& probe) {
  auto target = std::string(probe.kernel_fn);
  if (probe.is_syscall) {
  target = bpf_.get_syscall_fnname(target);
  }
  return target;
 }
 
-void BCCWrapper::PollPerfBuffer(std::string_view perf_buffer_name, int timeout_ms) {
+void BCCWrapperImpl::PollPerfBuffer(std::string_view perf_buffer_name, int timeout_ms) {
  auto perf_buffer = bpf_.get_perf_buffer(std::string(perf_buffer_name));
  if (perf_buffer != nullptr) {
  perf_buffer->poll(timeout_ms);
  }
 }
 
-void BCCWrapper::PollPerfBuffers(int timeout_ms) {
+void BCCWrapperImpl::PollPerfBuffers(int timeout_ms) {
  for (const auto& spec : perf_buffers_) {
  PollPerfBuffer(spec.name, timeout_ms);
  }
 }
 
-void BCCWrapper::Close() {
+void BCCWrapperImpl::Close() {
  DetachPerfEvents();
  ClosePerfBuffers();
  DetachKProbes();
  DetachUProbes();
  DetachTracepoints();
 }
 
+std::unique_ptr<BCCWrapper> CreateBCC() { return std::make_unique<BCCWrapperImpl>(); }
+
 } // namespace bpf_tools
 } // namespace stirling
 } // namespace px