platform_system_core/libmodprobe/libmodprobe.cpp
Chungkai c60300a2cc Load kernel modules in parallel
First, we load independent module in parallel, then we singly load
modules which have soft-dependencies. then remove them from dependency
list of other modules. Repeat these steps until all modules are loaded.

Bug: 180676019
Test: boot successfully, and save more than 400 ms on Pixel 6 Pro.
Signed-off-by: chungkai <chungkai@google.com>
Change-Id: Ib844cfee72d4049bd951528692c818b4fa6c8e8f
2022-03-18 08:06:07 +00:00

598 lines
19 KiB
C++

/*
* Copyright (C) 2018 The Android Open Source Project
*
* 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 <modprobe/modprobe.h>
#include <fnmatch.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <algorithm>
#include <map>
#include <set>
#include <string>
#include <thread>
#include <vector>
#include <android-base/chrono_utils.h>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
std::string Modprobe::MakeCanonical(const std::string& module_path) {
auto start = module_path.find_last_of('/');
if (start == std::string::npos) {
start = 0;
} else {
start += 1;
}
auto end = module_path.size();
if (android::base::EndsWith(module_path, ".ko")) {
end -= 3;
}
if ((end - start) <= 1) {
LOG(ERROR) << "malformed module name: " << module_path;
return "";
}
std::string module_name = module_path.substr(start, end - start);
// module names can have '-', but their file names will have '_'
std::replace(module_name.begin(), module_name.end(), '-', '_');
return module_name;
}
bool Modprobe::ParseDepCallback(const std::string& base_path,
const std::vector<std::string>& args) {
std::vector<std::string> deps;
std::string prefix = "";
// Set first item as our modules path
std::string::size_type pos = args[0].find(':');
if (args[0][0] != '/') {
prefix = base_path + "/";
}
if (pos != std::string::npos) {
deps.emplace_back(prefix + args[0].substr(0, pos));
} else {
LOG(ERROR) << "dependency lines must start with name followed by ':'";
return false;
}
// Remaining items are dependencies of our module
for (auto arg = args.begin() + 1; arg != args.end(); ++arg) {
if ((*arg)[0] != '/') {
prefix = base_path + "/";
} else {
prefix = "";
}
deps.push_back(prefix + *arg);
}
std::string canonical_name = MakeCanonical(args[0].substr(0, pos));
if (canonical_name.empty()) {
return false;
}
this->module_deps_[canonical_name] = deps;
return true;
}
bool Modprobe::ParseAliasCallback(const std::vector<std::string>& args) {
auto it = args.begin();
const std::string& type = *it++;
if (type != "alias") {
LOG(ERROR) << "non-alias line encountered in modules.alias, found " << type;
return false;
}
if (args.size() != 3) {
LOG(ERROR) << "alias lines in modules.alias must have 3 entries, not " << args.size();
return false;
}
const std::string& alias = *it++;
const std::string& module_name = *it++;
this->module_aliases_.emplace_back(alias, module_name);
return true;
}
bool Modprobe::ParseSoftdepCallback(const std::vector<std::string>& args) {
auto it = args.begin();
const std::string& type = *it++;
std::string state = "";
if (type != "softdep") {
LOG(ERROR) << "non-softdep line encountered in modules.softdep, found " << type;
return false;
}
if (args.size() < 4) {
LOG(ERROR) << "softdep lines in modules.softdep must have at least 4 entries";
return false;
}
const std::string& module = *it++;
while (it != args.end()) {
const std::string& token = *it++;
if (token == "pre:" || token == "post:") {
state = token;
continue;
}
if (state == "") {
LOG(ERROR) << "malformed modules.softdep at token " << token;
return false;
}
if (state == "pre:") {
this->module_pre_softdep_.emplace_back(module, token);
} else {
this->module_post_softdep_.emplace_back(module, token);
}
}
return true;
}
bool Modprobe::ParseLoadCallback(const std::vector<std::string>& args) {
auto it = args.begin();
const std::string& module = *it++;
const std::string& canonical_name = MakeCanonical(module);
if (canonical_name.empty()) {
return false;
}
this->module_load_.emplace_back(canonical_name);
return true;
}
bool Modprobe::ParseOptionsCallback(const std::vector<std::string>& args) {
auto it = args.begin();
const std::string& type = *it++;
if (type != "options") {
LOG(ERROR) << "non-options line encountered in modules.options";
return false;
}
if (args.size() < 2) {
LOG(ERROR) << "lines in modules.options must have at least 2 entries, not " << args.size();
return false;
}
const std::string& module = *it++;
std::string options = "";
const std::string& canonical_name = MakeCanonical(module);
if (canonical_name.empty()) {
return false;
}
while (it != args.end()) {
options += *it++;
if (it != args.end()) {
options += " ";
}
}
auto [unused, inserted] = this->module_options_.emplace(canonical_name, options);
if (!inserted) {
LOG(ERROR) << "multiple options lines present for module " << module;
return false;
}
return true;
}
bool Modprobe::ParseBlocklistCallback(const std::vector<std::string>& args) {
auto it = args.begin();
const std::string& type = *it++;
if (type != "blocklist") {
LOG(ERROR) << "non-blocklist line encountered in modules.blocklist";
return false;
}
if (args.size() != 2) {
LOG(ERROR) << "lines in modules.blocklist must have exactly 2 entries, not " << args.size();
return false;
}
const std::string& module = *it++;
const std::string& canonical_name = MakeCanonical(module);
if (canonical_name.empty()) {
return false;
}
this->module_blocklist_.emplace(canonical_name);
return true;
}
void Modprobe::ParseCfg(const std::string& cfg,
std::function<bool(const std::vector<std::string>&)> f) {
std::string cfg_contents;
if (!android::base::ReadFileToString(cfg, &cfg_contents, false)) {
return;
}
std::vector<std::string> lines = android::base::Split(cfg_contents, "\n");
for (const std::string line : lines) {
if (line.empty() || line[0] == '#') {
continue;
}
const std::vector<std::string> args = android::base::Split(line, " ");
if (args.empty()) continue;
f(args);
}
return;
}
void Modprobe::AddOption(const std::string& module_name, const std::string& option_name,
const std::string& value) {
auto canonical_name = MakeCanonical(module_name);
auto options_iter = module_options_.find(canonical_name);
auto option_str = option_name + "=" + value;
if (options_iter != module_options_.end()) {
options_iter->second = options_iter->second + " " + option_str;
} else {
module_options_.emplace(canonical_name, option_str);
}
}
void Modprobe::ParseKernelCmdlineOptions(void) {
std::string cmdline = GetKernelCmdline();
std::string module_name = "";
std::string option_name = "";
std::string value = "";
bool in_module = true;
bool in_option = false;
bool in_value = false;
bool in_quotes = false;
int start = 0;
for (int i = 0; i < cmdline.size(); i++) {
if (cmdline[i] == '"') {
in_quotes = !in_quotes;
}
if (in_quotes) continue;
if (cmdline[i] == ' ') {
if (in_value) {
value = cmdline.substr(start, i - start);
if (!module_name.empty() && !option_name.empty()) {
AddOption(module_name, option_name, value);
}
}
module_name = "";
option_name = "";
value = "";
in_value = false;
start = i + 1;
in_module = true;
continue;
}
if (cmdline[i] == '.') {
if (in_module) {
module_name = cmdline.substr(start, i - start);
start = i + 1;
in_module = false;
}
in_option = true;
continue;
}
if (cmdline[i] == '=') {
if (in_option) {
option_name = cmdline.substr(start, i - start);
start = i + 1;
in_option = false;
}
in_value = true;
continue;
}
}
if (in_value && !in_quotes) {
value = cmdline.substr(start, cmdline.size() - start);
if (!module_name.empty() && !option_name.empty()) {
AddOption(module_name, option_name, value);
}
}
}
Modprobe::Modprobe(const std::vector<std::string>& base_paths, const std::string load_file,
bool use_blocklist)
: blocklist_enabled(use_blocklist) {
using namespace std::placeholders;
for (const auto& base_path : base_paths) {
auto alias_callback = std::bind(&Modprobe::ParseAliasCallback, this, _1);
ParseCfg(base_path + "/modules.alias", alias_callback);
auto dep_callback = std::bind(&Modprobe::ParseDepCallback, this, base_path, _1);
ParseCfg(base_path + "/modules.dep", dep_callback);
auto softdep_callback = std::bind(&Modprobe::ParseSoftdepCallback, this, _1);
ParseCfg(base_path + "/modules.softdep", softdep_callback);
auto load_callback = std::bind(&Modprobe::ParseLoadCallback, this, _1);
ParseCfg(base_path + "/" + load_file, load_callback);
auto options_callback = std::bind(&Modprobe::ParseOptionsCallback, this, _1);
ParseCfg(base_path + "/modules.options", options_callback);
auto blocklist_callback = std::bind(&Modprobe::ParseBlocklistCallback, this, _1);
ParseCfg(base_path + "/modules.blocklist", blocklist_callback);
}
ParseKernelCmdlineOptions();
}
std::vector<std::string> Modprobe::GetDependencies(const std::string& module) {
auto it = module_deps_.find(module);
if (it == module_deps_.end()) {
return {};
}
return it->second;
}
bool Modprobe::InsmodWithDeps(const std::string& module_name, const std::string& parameters) {
if (module_name.empty()) {
LOG(ERROR) << "Need valid module name, given: " << module_name;
return false;
}
auto dependencies = GetDependencies(module_name);
if (dependencies.empty()) {
LOG(ERROR) << "Module " << module_name << " not in dependency file";
return false;
}
// load module dependencies in reverse order
for (auto dep = dependencies.rbegin(); dep != dependencies.rend() - 1; ++dep) {
LOG(VERBOSE) << "Loading hard dep for '" << module_name << "': " << *dep;
if (!LoadWithAliases(*dep, true)) {
return false;
}
}
// try to load soft pre-dependencies
for (const auto& [module, softdep] : module_pre_softdep_) {
if (module_name == module) {
LOG(VERBOSE) << "Loading soft pre-dep for '" << module << "': " << softdep;
LoadWithAliases(softdep, false);
}
}
// load target module itself with args
if (!Insmod(dependencies[0], parameters)) {
return false;
}
// try to load soft post-dependencies
for (const auto& [module, softdep] : module_post_softdep_) {
if (module_name == module) {
LOG(VERBOSE) << "Loading soft post-dep for '" << module << "': " << softdep;
LoadWithAliases(softdep, false);
}
}
return true;
}
bool Modprobe::LoadWithAliases(const std::string& module_name, bool strict,
const std::string& parameters) {
auto canonical_name = MakeCanonical(module_name);
if (module_loaded_.count(canonical_name)) {
return true;
}
std::set<std::string> modules_to_load = {canonical_name};
bool module_loaded = false;
// use aliases to expand list of modules to load (multiple modules
// may alias themselves to the requested name)
for (const auto& [alias, aliased_module] : module_aliases_) {
if (fnmatch(alias.c_str(), module_name.c_str(), 0) != 0) continue;
LOG(VERBOSE) << "Found alias for '" << module_name << "': '" << aliased_module;
if (module_loaded_.count(MakeCanonical(aliased_module))) continue;
modules_to_load.emplace(aliased_module);
}
// attempt to load all modules aliased to this name
for (const auto& module : modules_to_load) {
if (!ModuleExists(module)) continue;
if (InsmodWithDeps(module, parameters)) module_loaded = true;
}
if (strict && !module_loaded) {
LOG(ERROR) << "LoadWithAliases was unable to load " << module_name;
return false;
}
return true;
}
bool Modprobe::IsBlocklisted(const std::string& module_name) {
if (!blocklist_enabled) return false;
auto canonical_name = MakeCanonical(module_name);
auto dependencies = GetDependencies(canonical_name);
for (auto dep = dependencies.begin(); dep != dependencies.end(); ++dep) {
if (module_blocklist_.count(MakeCanonical(*dep))) return true;
}
return module_blocklist_.count(canonical_name) > 0;
}
// Another option to load kernel modules. load in independent modules in parallel
// and then load modules which only have soft dependency, third update dependency list of other
// remaining modules, repeat these steps until all modules are loaded.
bool Modprobe::LoadModulesParallel(int num_threads) {
bool ret = true;
std::map<std::string, std::set<std::string>> mod_with_deps;
std::map<std::string, std::set<std::string>> mod_with_softdeps;
// Get dependencies
for (const auto& module : module_load_) {
auto dependencies = GetDependencies(MakeCanonical(module));
for (auto dep = dependencies.rbegin(); dep != dependencies.rend(); dep++) {
mod_with_deps[module].emplace(*dep);
}
}
// Get soft dependencies
for (const auto& [it_mod, it_softdep] : module_pre_softdep_) {
mod_with_softdeps[MakeCanonical(it_mod)].emplace(it_softdep);
}
// Get soft post dependencies
for (const auto& [it_mod, it_softdep] : module_post_softdep_) {
mod_with_softdeps[MakeCanonical(it_mod)].emplace(it_softdep);
}
while (!mod_with_deps.empty()) {
std::vector<std::thread> threads;
std::vector<std::string> mods_path_to_load;
std::vector<std::string> mods_with_softdep_to_load;
std::mutex vector_lock;
// Find independent modules and modules only having soft dependencies
for (const auto& [it_mod, it_dep] : mod_with_deps) {
if (it_dep.size() == 1 && mod_with_softdeps[it_mod].empty()) {
mods_path_to_load.emplace_back(*(it_dep.begin()));
} else if (it_dep.size() == 1) {
mods_with_softdep_to_load.emplace_back(it_mod);
}
}
// Load independent modules in parallel
auto thread_function = [&] {
std::unique_lock lk(vector_lock);
while (!mods_path_to_load.empty()) {
auto mod_path_to_load = std::move(mods_path_to_load.back());
mods_path_to_load.pop_back();
lk.unlock();
ret &= Insmod(mod_path_to_load, "");
lk.lock();
}
};
std::generate_n(std::back_inserter(threads), num_threads,
[&] { return std::thread(thread_function); });
// Wait for the threads.
for (auto& thread : threads) {
thread.join();
}
// Since we cannot assure if these soft dependencies tree are overlap,
// we loaded these modules one by one.
for (auto dep = mods_with_softdep_to_load.rbegin(); dep != mods_with_softdep_to_load.rend();
dep++) {
ret &= LoadWithAliases(*dep, true);
}
std::lock_guard guard(module_loaded_lock_);
// Remove loaded module form mod_with_deps and soft dependencies of other modules
for (const auto& module_loaded : module_loaded_) {
mod_with_deps.erase(module_loaded);
for (auto& [mod, softdeps] : mod_with_softdeps) {
softdeps.erase(module_loaded);
}
}
// Remove loaded module form dependencies of other modules which are not loaded yet
for (const auto& module_loaded_path : module_loaded_paths_) {
for (auto& [mod, deps] : mod_with_deps) {
deps.erase(module_loaded_path);
}
}
}
return ret;
}
bool Modprobe::LoadListedModules(bool strict) {
auto ret = true;
for (const auto& module : module_load_) {
if (!LoadWithAliases(module, true)) {
if (IsBlocklisted(module)) continue;
ret = false;
if (strict) break;
}
}
return ret;
}
bool Modprobe::Remove(const std::string& module_name) {
auto dependencies = GetDependencies(MakeCanonical(module_name));
for (auto dep = dependencies.begin(); dep != dependencies.end(); ++dep) {
Rmmod(*dep);
}
Rmmod(module_name);
return true;
}
std::vector<std::string> Modprobe::ListModules(const std::string& pattern) {
std::vector<std::string> rv;
for (const auto& [module, deps] : module_deps_) {
// Attempt to match both the canonical module name and the module filename.
if (!fnmatch(pattern.c_str(), module.c_str(), 0)) {
rv.emplace_back(module);
} else if (!fnmatch(pattern.c_str(), basename(deps[0].c_str()), 0)) {
rv.emplace_back(deps[0]);
}
}
return rv;
}
bool Modprobe::GetAllDependencies(const std::string& module,
std::vector<std::string>* pre_dependencies,
std::vector<std::string>* dependencies,
std::vector<std::string>* post_dependencies) {
std::string canonical_name = MakeCanonical(module);
if (pre_dependencies) {
pre_dependencies->clear();
for (const auto& [it_module, it_softdep] : module_pre_softdep_) {
if (canonical_name == it_module) {
pre_dependencies->emplace_back(it_softdep);
}
}
}
if (dependencies) {
dependencies->clear();
auto hard_deps = GetDependencies(canonical_name);
if (hard_deps.empty()) {
return false;
}
for (auto dep = hard_deps.rbegin(); dep != hard_deps.rend(); dep++) {
dependencies->emplace_back(*dep);
}
}
if (post_dependencies) {
for (const auto& [it_module, it_softdep] : module_post_softdep_) {
if (canonical_name == it_module) {
post_dependencies->emplace_back(it_softdep);
}
}
}
return true;
}