88 lines · cpp
1//===-- Procfs.cpp --------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "Procfs.h"10#include "lldb/Host/posix/Support.h"11#include "llvm/ADT/StringExtras.h"12#include "llvm/Support/Error.h"13#include "llvm/Support/MemoryBuffer.h"14#include "llvm/Support/Threading.h"15#include <optional>16 17using namespace lldb;18using namespace lldb_private;19using namespace process_linux;20using namespace llvm;21 22Expected<ArrayRef<uint8_t>> lldb_private::process_linux::GetProcfsCpuInfo() {23 static ErrorOr<std::unique_ptr<MemoryBuffer>> cpu_info_or_err =24 getProcFile("cpuinfo");25 26 if (!*cpu_info_or_err)27 cpu_info_or_err.getError();28 29 MemoryBuffer &buffer = **cpu_info_or_err;30 return arrayRefFromStringRef(buffer.getBuffer());31}32 33Expected<std::vector<cpu_id_t>>34lldb_private::process_linux::GetAvailableLogicalCoreIDs(StringRef cpuinfo) {35 SmallVector<StringRef, 8> lines;36 cpuinfo.split(lines, "\n", /*MaxSplit=*/-1, /*KeepEmpty=*/false);37 std::vector<cpu_id_t> logical_cores;38 39 for (StringRef line : lines) {40 std::pair<StringRef, StringRef> key_value = line.split(':');41 auto key = key_value.first.trim();42 auto val = key_value.second.trim();43 if (key == "processor") {44 cpu_id_t processor;45 if (val.getAsInteger(10, processor))46 return createStringError(47 inconvertibleErrorCode(),48 "Failed parsing the /proc/cpuinfo line entry: %s", line.data());49 logical_cores.push_back(processor);50 }51 }52 return logical_cores;53}54 55llvm::Expected<llvm::ArrayRef<cpu_id_t>>56lldb_private::process_linux::GetAvailableLogicalCoreIDs() {57 static std::optional<std::vector<cpu_id_t>> logical_cores_ids;58 if (!logical_cores_ids) {59 // We find the actual list of core ids by parsing /proc/cpuinfo60 Expected<ArrayRef<uint8_t>> cpuinfo = GetProcfsCpuInfo();61 if (!cpuinfo)62 return cpuinfo.takeError();63 64 Expected<std::vector<cpu_id_t>> cpu_ids = GetAvailableLogicalCoreIDs(65 StringRef(reinterpret_cast<const char *>(cpuinfo->data())));66 if (!cpu_ids)67 return cpu_ids.takeError();68 69 logical_cores_ids.emplace(std::move(*cpu_ids));70 }71 return *logical_cores_ids;72}73 74llvm::Expected<int> lldb_private::process_linux::GetPtraceScope() {75 ErrorOr<std::unique_ptr<MemoryBuffer>> ptrace_scope_file =76 getProcFile("sys/kernel/yama/ptrace_scope");77 if (!ptrace_scope_file)78 return errorCodeToError(ptrace_scope_file.getError());79 // The contents should be something like "1\n". Trim it so we get "1".80 StringRef buffer = (*ptrace_scope_file)->getBuffer().trim();81 int ptrace_scope_value;82 if (buffer.getAsInteger(10, ptrace_scope_value)) {83 return createStringError(inconvertibleErrorCode(),84 "Invalid ptrace_scope value: '%s'", buffer.data());85 }86 return ptrace_scope_value;87}88