#include "environment.h"
+#include <inttypes.h>
+#include <stdio.h>
#include <stdlib.h>
+
+#include <limits>
+#include <set>
+#include <unordered_map>
#include <vector>
-#include <base/logging.h>
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/parseint.h>
+#include <android-base/strings.h>
+#include <android-base/stringprintf.h>
+
+#if defined(__ANDROID__)
+#include <sys/system_properties.h>
+#endif
+#include "read_elf.h"
#include "utils.h"
+class LineReader {
+ public:
+ LineReader(FILE* fp) : fp_(fp), buf_(nullptr), bufsize_(0) {
+ }
+
+ ~LineReader() {
+ free(buf_);
+ fclose(fp_);
+ }
+
+ char* ReadLine() {
+ if (getline(&buf_, &bufsize_, fp_) != -1) {
+ return buf_;
+ }
+ return nullptr;
+ }
+
+ size_t MaxLineSize() {
+ return bufsize_;
+ }
+
+ private:
+ FILE* fp_;
+ char* buf_;
+ size_t bufsize_;
+};
+
std::vector<int> GetOnlineCpus() {
std::vector<int> result;
FILE* fp = fopen("/sys/devices/system/cpu/online", "re");
LineReader reader(fp);
char* line;
if ((line = reader.ReadLine()) != nullptr) {
- result = GetOnlineCpusFromString(line);
+ result = GetCpusFromString(line);
}
CHECK(!result.empty()) << "can't get online cpu information";
return result;
}
-std::vector<int> GetOnlineCpusFromString(const std::string& s) {
- std::vector<int> result;
+std::vector<int> GetCpusFromString(const std::string& s) {
+ std::set<int> cpu_set;
bool have_dash = false;
const char* p = s.c_str();
char* endp;
+ int last_cpu;
long cpu;
// Parse line like: 0,1-3, 5, 7-8
while ((cpu = strtol(p, &endp, 10)) != 0 || endp != p) {
- if (have_dash && result.size() > 0) {
- for (int t = result.back() + 1; t < cpu; ++t) {
- result.push_back(t);
+ if (have_dash && !cpu_set.empty()) {
+ for (int t = last_cpu + 1; t < cpu; ++t) {
+ cpu_set.insert(t);
}
}
have_dash = false;
- result.push_back(cpu);
+ cpu_set.insert(cpu);
+ last_cpu = cpu;
p = endp;
while (!isdigit(*p) && *p != '\0') {
if (*p == '-') {
++p;
}
}
+ return std::vector<int>(cpu_set.begin(), cpu_set.end());
+}
+
+bool ProcessKernelSymbols(const std::string& symbol_file,
+ std::function<bool(const KernelSymbol&)> callback) {
+ FILE* fp = fopen(symbol_file.c_str(), "re");
+ if (fp == nullptr) {
+ PLOG(ERROR) << "failed to open file " << symbol_file;
+ return false;
+ }
+ LineReader reader(fp);
+ char* line;
+ while ((line = reader.ReadLine()) != nullptr) {
+ // Parse line like: ffffffffa005c4e4 d __warned.41698 [libsas]
+ char name[reader.MaxLineSize()];
+ char module[reader.MaxLineSize()];
+ strcpy(module, "");
+
+ KernelSymbol symbol;
+ if (sscanf(line, "%" PRIx64 " %c %s%s", &symbol.addr, &symbol.type, name, module) < 3) {
+ continue;
+ }
+ symbol.name = name;
+ size_t module_len = strlen(module);
+ if (module_len > 2 && module[0] == '[' && module[module_len - 1] == ']') {
+ module[module_len - 1] = '\0';
+ symbol.module = &module[1];
+ } else {
+ symbol.module = nullptr;
+ }
+
+ if (callback(symbol)) {
+ return true;
+ }
+ }
+ return false;
+}
+
+static std::vector<KernelMmap> GetLoadedModules() {
+ std::vector<KernelMmap> result;
+ FILE* fp = fopen("/proc/modules", "re");
+ if (fp == nullptr) {
+ // There is no /proc/modules on Android devices, so we don't print error if failed to open it.
+ PLOG(DEBUG) << "failed to open file /proc/modules";
+ return result;
+ }
+ LineReader reader(fp);
+ char* line;
+ while ((line = reader.ReadLine()) != nullptr) {
+ // Parse line like: nf_defrag_ipv6 34768 1 nf_conntrack_ipv6, Live 0xffffffffa0fe5000
+ char name[reader.MaxLineSize()];
+ uint64_t addr;
+ if (sscanf(line, "%s%*lu%*u%*s%*s 0x%" PRIx64, name, &addr) == 2) {
+ KernelMmap map;
+ map.name = name;
+ map.start_addr = addr;
+ result.push_back(map);
+ }
+ }
return result;
}
+
+static std::string GetLinuxVersion() {
+ std::string content;
+ if (android::base::ReadFileToString("/proc/version", &content)) {
+ char s[content.size() + 1];
+ if (sscanf(content.c_str(), "Linux version %s", s) == 1) {
+ return s;
+ }
+ }
+ PLOG(FATAL) << "can't read linux version";
+ return "";
+}
+
+static void GetAllModuleFiles(const std::string& path,
+ std::unordered_map<std::string, std::string>* module_file_map) {
+ std::vector<std::string> files;
+ std::vector<std::string> subdirs;
+ GetEntriesInDir(path, &files, &subdirs);
+ for (auto& name : files) {
+ if (android::base::EndsWith(name, ".ko")) {
+ std::string module_name = name.substr(0, name.size() - 3);
+ std::replace(module_name.begin(), module_name.end(), '-', '_');
+ module_file_map->insert(std::make_pair(module_name, path + "/" + name));
+ }
+ }
+ for (auto& name : subdirs) {
+ GetAllModuleFiles(path + "/" + name, module_file_map);
+ }
+}
+
+static std::vector<KernelMmap> GetModulesInUse() {
+ // TODO: There is no /proc/modules or /lib/modules on Android, find methods work on it.
+ std::vector<KernelMmap> module_mmaps = GetLoadedModules();
+ std::string linux_version = GetLinuxVersion();
+ std::string module_dirpath = "/lib/modules/" + linux_version + "/kernel";
+ std::unordered_map<std::string, std::string> module_file_map;
+ GetAllModuleFiles(module_dirpath, &module_file_map);
+ for (auto& module : module_mmaps) {
+ auto it = module_file_map.find(module.name);
+ if (it != module_file_map.end()) {
+ module.filepath = it->second;
+ }
+ }
+ return module_mmaps;
+}
+
+void GetKernelAndModuleMmaps(KernelMmap* kernel_mmap, std::vector<KernelMmap>* module_mmaps) {
+ kernel_mmap->name = DEFAULT_KERNEL_MMAP_NAME;
+ kernel_mmap->start_addr = 0;
+ kernel_mmap->filepath = kernel_mmap->name;
+ *module_mmaps = GetModulesInUse();
+ for (auto& map : *module_mmaps) {
+ if (map.filepath.empty()) {
+ map.filepath = "[" + map.name + "]";
+ }
+ }
+
+ if (module_mmaps->size() == 0) {
+ kernel_mmap->len = std::numeric_limits<unsigned long long>::max() - kernel_mmap->start_addr;
+ } else {
+ std::sort(
+ module_mmaps->begin(), module_mmaps->end(),
+ [](const KernelMmap& m1, const KernelMmap& m2) { return m1.start_addr < m2.start_addr; });
+ // When not having enough privilege, all addresses are read as 0.
+ if (kernel_mmap->start_addr == (*module_mmaps)[0].start_addr) {
+ kernel_mmap->len = 0;
+ } else {
+ kernel_mmap->len = (*module_mmaps)[0].start_addr - kernel_mmap->start_addr - 1;
+ }
+ for (size_t i = 0; i + 1 < module_mmaps->size(); ++i) {
+ if ((*module_mmaps)[i].start_addr == (*module_mmaps)[i + 1].start_addr) {
+ (*module_mmaps)[i].len = 0;
+ } else {
+ (*module_mmaps)[i].len =
+ (*module_mmaps)[i + 1].start_addr - (*module_mmaps)[i].start_addr - 1;
+ }
+ }
+ module_mmaps->back().len =
+ std::numeric_limits<unsigned long long>::max() - module_mmaps->back().start_addr;
+ }
+}
+
+static bool ReadThreadNameAndTgid(const std::string& status_file, std::string* comm, pid_t* tgid) {
+ FILE* fp = fopen(status_file.c_str(), "re");
+ if (fp == nullptr) {
+ return false;
+ }
+ bool read_comm = false;
+ bool read_tgid = false;
+ LineReader reader(fp);
+ char* line;
+ while ((line = reader.ReadLine()) != nullptr) {
+ char s[reader.MaxLineSize()];
+ if (sscanf(line, "Name:%s", s) == 1) {
+ *comm = s;
+ read_comm = true;
+ } else if (sscanf(line, "Tgid:%d", tgid) == 1) {
+ read_tgid = true;
+ }
+ if (read_comm && read_tgid) {
+ return true;
+ }
+ }
+ return false;
+}
+
+static std::vector<pid_t> GetThreadsInProcess(pid_t pid) {
+ std::vector<pid_t> result;
+ std::string task_dirname = android::base::StringPrintf("/proc/%d/task", pid);
+ std::vector<std::string> subdirs;
+ GetEntriesInDir(task_dirname, nullptr, &subdirs);
+ for (const auto& name : subdirs) {
+ int tid;
+ if (!android::base::ParseInt(name.c_str(), &tid, 0)) {
+ continue;
+ }
+ result.push_back(tid);
+ }
+ return result;
+}
+
+static bool GetThreadComm(pid_t pid, std::vector<ThreadComm>* thread_comms) {
+ std::vector<pid_t> tids = GetThreadsInProcess(pid);
+ for (auto& tid : tids) {
+ std::string status_file = android::base::StringPrintf("/proc/%d/task/%d/status", pid, tid);
+ std::string comm;
+ pid_t tgid;
+ // It is possible that the process or thread exited before we can read its status.
+ if (!ReadThreadNameAndTgid(status_file, &comm, &tgid)) {
+ continue;
+ }
+ CHECK_EQ(pid, tgid);
+ ThreadComm thread;
+ thread.tid = tid;
+ thread.pid = pid;
+ thread.comm = comm;
+ thread_comms->push_back(thread);
+ }
+ return true;
+}
+
+bool GetThreadComms(std::vector<ThreadComm>* thread_comms) {
+ thread_comms->clear();
+ std::vector<std::string> subdirs;
+ GetEntriesInDir("/proc", nullptr, &subdirs);
+ for (auto& name : subdirs) {
+ int pid;
+ if (!android::base::ParseInt(name.c_str(), &pid, 0)) {
+ continue;
+ }
+ if (!GetThreadComm(pid, thread_comms)) {
+ return false;
+ }
+ }
+ return true;
+}
+
+bool GetThreadMmapsInProcess(pid_t pid, std::vector<ThreadMmap>* thread_mmaps) {
+ std::string map_file = android::base::StringPrintf("/proc/%d/maps", pid);
+ FILE* fp = fopen(map_file.c_str(), "re");
+ if (fp == nullptr) {
+ PLOG(DEBUG) << "can't open file " << map_file;
+ return false;
+ }
+ thread_mmaps->clear();
+ LineReader reader(fp);
+ char* line;
+ while ((line = reader.ReadLine()) != nullptr) {
+ // Parse line like: 00400000-00409000 r-xp 00000000 fc:00 426998 /usr/lib/gvfs/gvfsd-http
+ uint64_t start_addr, end_addr, pgoff;
+ char type[reader.MaxLineSize()];
+ char execname[reader.MaxLineSize()];
+ strcpy(execname, "");
+ if (sscanf(line, "%" PRIx64 "-%" PRIx64 " %s %" PRIx64 " %*x:%*x %*u %s\n", &start_addr,
+ &end_addr, type, &pgoff, execname) < 4) {
+ continue;
+ }
+ if (strcmp(execname, "") == 0) {
+ strcpy(execname, DEFAULT_EXECNAME_FOR_THREAD_MMAP);
+ }
+ ThreadMmap thread;
+ thread.start_addr = start_addr;
+ thread.len = end_addr - start_addr;
+ thread.pgoff = pgoff;
+ thread.name = execname;
+ thread.executable = (type[2] == 'x');
+ thread_mmaps->push_back(thread);
+ }
+ return true;
+}
+
+bool GetKernelBuildId(BuildId* build_id) {
+ return GetBuildIdFromNoteFile("/sys/kernel/notes", build_id);
+}
+
+bool GetModuleBuildId(const std::string& module_name, BuildId* build_id) {
+ std::string notefile = "/sys/module/" + module_name + "/notes/.note.gnu.build-id";
+ return GetBuildIdFromNoteFile(notefile, build_id);
+}
+
+bool GetValidThreadsFromProcessString(const std::string& pid_str, std::set<pid_t>* tid_set) {
+ std::vector<std::string> strs = android::base::Split(pid_str, ",");
+ for (const auto& s : strs) {
+ int pid;
+ if (!android::base::ParseInt(s.c_str(), &pid, 0)) {
+ LOG(ERROR) << "Invalid pid '" << s << "'";
+ return false;
+ }
+ std::vector<pid_t> tids = GetThreadsInProcess(pid);
+ if (tids.empty()) {
+ LOG(ERROR) << "Non existing process '" << pid << "'";
+ return false;
+ }
+ tid_set->insert(tids.begin(), tids.end());
+ }
+ return true;
+}
+
+bool GetValidThreadsFromThreadString(const std::string& tid_str, std::set<pid_t>* tid_set) {
+ std::vector<std::string> strs = android::base::Split(tid_str, ",");
+ for (const auto& s : strs) {
+ int tid;
+ if (!android::base::ParseInt(s.c_str(), &tid, 0)) {
+ LOG(ERROR) << "Invalid tid '" << s << "'";
+ return false;
+ }
+ if (!IsDir(android::base::StringPrintf("/proc/%d", tid))) {
+ LOG(ERROR) << "Non existing thread '" << tid << "'";
+ return false;
+ }
+ tid_set->insert(tid);
+ }
+ return true;
+}
+
+bool GetExecPath(std::string* exec_path) {
+ char path[PATH_MAX];
+ ssize_t path_len = readlink("/proc/self/exe", path, sizeof(path));
+ if (path_len <= 0 || path_len >= static_cast<ssize_t>(sizeof(path))) {
+ PLOG(ERROR) << "readlink failed";
+ return false;
+ }
+ path[path_len] = '\0';
+ *exec_path = path;
+ return true;
+}
+
+/*
+ * perf event paranoia level:
+ * -1 - not paranoid at all
+ * 0 - disallow raw tracepoint access for unpriv
+ * 1 - disallow cpu events for unpriv
+ * 2 - disallow kernel profiling for unpriv
+ * 3 - disallow user profiling for unpriv
+ */
+static bool ReadPerfEventParanoid(int* value) {
+ std::string s;
+ if (!android::base::ReadFileToString("/proc/sys/kernel/perf_event_paranoid", &s)) {
+ PLOG(ERROR) << "failed to read /proc/sys/kernel/perf_event_paranoid";
+ return false;
+ }
+ s = android::base::Trim(s);
+ if (!android::base::ParseInt(s.c_str(), value)) {
+ PLOG(ERROR) << "failed to parse /proc/sys/kernel/perf_event_paranoid: " << s;
+ return false;
+ }
+ return true;
+}
+
+static const char* GetLimitLevelDescription(int limit_level) {
+ switch (limit_level) {
+ case -1: return "unlimited";
+ case 0: return "disallowing raw tracepoint access for unpriv";
+ case 1: return "disallowing cpu events for unpriv";
+ case 2: return "disallowing kernel profiling for unpriv";
+ case 3: return "disallowing user profiling for unpriv";
+ default: return "unknown level";
+ }
+}
+
+bool CheckPerfEventLimit() {
+ // root is not limited by /proc/sys/kernel/perf_event_paranoid.
+ if (IsRoot()) {
+ return true;
+ }
+ int limit_level;
+ if (!ReadPerfEventParanoid(&limit_level)) {
+ return false;
+ }
+ if (limit_level <= 1) {
+ return true;
+ }
+#if defined(__ANDROID__)
+ // Try to enable perf_event_paranoid by setprop security.perf_harden=0.
+ if (__system_property_set("security.perf_harden", "0") == 0) {
+ sleep(1);
+ if (ReadPerfEventParanoid(&limit_level) && limit_level <= 1) {
+ return true;
+ }
+ }
+ LOG(WARNING) << "/proc/sys/kernel/perf_event_paranoid is " << limit_level
+ << ", " << GetLimitLevelDescription(limit_level) << ".";
+ LOG(WARNING) << "Try using `adb shell setprop security.perf_harden 0` to allow profiling.";
+#else
+ LOG(WARNING) << "/proc/sys/kernel/perf_event_paranoid is " << limit_level
+ << ", " << GetLimitLevelDescription(limit_level) << ".";
+#endif
+ return true;
+}