Revert "libprocessgroup: Remove cgroup.rc file"
Revert submission 3212512
Reason for revert: Droidmonitor created revert due to b/372273614. Will be verifying through ABTD before submission.
Reverted changes: /q/submissionid:3212512
Change-Id: I37568516e973cb940f1229d52f94b8dc801da2ab
diff --git a/libprocessgroup/Android.bp b/libprocessgroup/Android.bp
index d623a11..a60bfe9 100644
--- a/libprocessgroup/Android.bp
+++ b/libprocessgroup/Android.bp
@@ -17,7 +17,7 @@
libprocessgroup_flag_aware_cc_defaults {
name: "libprocessgroup_build_flags_cc",
- cpp_std: "gnu++23",
+ cpp_std: "gnu++20",
soong_config_variables: {
memcg_v2_force_enabled: {
cflags: [
@@ -116,6 +116,5 @@
],
static_libs: [
"libgmock",
- "libprocessgroup_util",
],
}
diff --git a/libprocessgroup/cgroup_map.cpp b/libprocessgroup/cgroup_map.cpp
index aeccfe8..fb01cfd 100644
--- a/libprocessgroup/cgroup_map.cpp
+++ b/libprocessgroup/cgroup_map.cpp
@@ -151,7 +151,7 @@
void CgroupMap::Print() const {
if (!loaded_) {
LOG(ERROR) << "CgroupMap::Print called for [" << getpid()
- << "] failed, cgroups were not initialized properly";
+ << "] failed, RC file was not initialized properly";
return;
}
LOG(INFO) << "File version = " << ACgroupFile_getVersion();
@@ -221,7 +221,7 @@
if (__builtin_available(android 36, *)) {
max_activation_depth = ACgroupController_getMaxActivationDepth(controller);
}
- const int depth = GetCgroupDepth(ACgroupController_getPath(controller), path);
+ const int depth = util::GetCgroupDepth(ACgroupController_getPath(controller), path);
if (flags & CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION && depth < max_activation_depth) {
std::string str("+");
diff --git a/libprocessgroup/cgrouprc/Android.bp b/libprocessgroup/cgrouprc/Android.bp
index 38b2fa3..cb91247 100644
--- a/libprocessgroup/cgrouprc/Android.bp
+++ b/libprocessgroup/cgrouprc/Android.bp
@@ -49,8 +49,7 @@
"libbase",
],
static_libs: [
- "libjsoncpp",
- "libprocessgroup_util",
+ "libcgrouprc_format",
],
stubs: {
symbol_file: "libcgrouprc.map.txt",
diff --git a/libprocessgroup/cgrouprc/a_cgroup_file.cpp b/libprocessgroup/cgrouprc/a_cgroup_file.cpp
index 33c8376..e26d841 100644
--- a/libprocessgroup/cgrouprc/a_cgroup_file.cpp
+++ b/libprocessgroup/cgrouprc/a_cgroup_file.cpp
@@ -14,51 +14,93 @@
* limitations under the License.
*/
-#include <iterator>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include <memory>
#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+#include <android-base/unique_fd.h>
#include <android/cgrouprc.h>
-#include <processgroup/util.h>
+#include <processgroup/processgroup.h>
#include "cgrouprc_internal.h"
-static CgroupDescriptorMap* LoadDescriptors() {
- CgroupDescriptorMap* descriptors = new CgroupDescriptorMap;
- if (!ReadDescriptors(descriptors)) {
- LOG(ERROR) << "Failed to load cgroup description file";
+using android::base::StringPrintf;
+using android::base::unique_fd;
+
+using android::cgrouprc::format::CgroupController;
+using android::cgrouprc::format::CgroupFile;
+
+static CgroupFile* LoadRcFile() {
+ struct stat sb;
+
+ unique_fd fd(TEMP_FAILURE_RETRY(open(CGROUPS_RC_PATH, O_RDONLY | O_CLOEXEC)));
+ if (fd < 0) {
+ PLOG(ERROR) << "open() failed for " << CGROUPS_RC_PATH;
return nullptr;
}
- return descriptors;
+
+ if (fstat(fd, &sb) < 0) {
+ PLOG(ERROR) << "fstat() failed for " << CGROUPS_RC_PATH;
+ return nullptr;
+ }
+
+ size_t file_size = sb.st_size;
+ if (file_size < sizeof(CgroupFile)) {
+ LOG(ERROR) << "Invalid file format " << CGROUPS_RC_PATH;
+ return nullptr;
+ }
+
+ CgroupFile* file_data = (CgroupFile*)mmap(nullptr, file_size, PROT_READ, MAP_SHARED, fd, 0);
+ if (file_data == MAP_FAILED) {
+ PLOG(ERROR) << "Failed to mmap " << CGROUPS_RC_PATH;
+ return nullptr;
+ }
+
+ if (file_data->version_ != CgroupFile::FILE_CURR_VERSION) {
+ LOG(ERROR) << CGROUPS_RC_PATH << " file version mismatch";
+ munmap(file_data, file_size);
+ return nullptr;
+ }
+
+ auto expected = sizeof(CgroupFile) + file_data->controller_count_ * sizeof(CgroupController);
+ if (file_size != expected) {
+ LOG(ERROR) << CGROUPS_RC_PATH << " file has invalid size, expected " << expected
+ << ", actual " << file_size;
+ munmap(file_data, file_size);
+ return nullptr;
+ }
+
+ return file_data;
}
-static const CgroupDescriptorMap* GetInstance() {
+static CgroupFile* GetInstance() {
// Deliberately leak this object (not munmap) to avoid a race between destruction on
// process exit and concurrent access from another thread.
- static const CgroupDescriptorMap* descriptors = LoadDescriptors();
- return descriptors;
+ static auto* file = LoadRcFile();
+ return file;
}
uint32_t ACgroupFile_getVersion() {
- static constexpr uint32_t FILE_VERSION_1 = 1;
- auto descriptors = GetInstance();
- if (descriptors == nullptr) return 0;
- // There has only ever been one version, and there will be no more since cgroup.rc is no more
- return FILE_VERSION_1;
+ auto file = GetInstance();
+ if (file == nullptr) return 0;
+ return file->version_;
}
uint32_t ACgroupFile_getControllerCount() {
- auto descriptors = GetInstance();
- if (descriptors == nullptr) return 0;
- return descriptors->size();
+ auto file = GetInstance();
+ if (file == nullptr) return 0;
+ return file->controller_count_;
}
const ACgroupController* ACgroupFile_getController(uint32_t index) {
- auto descriptors = GetInstance();
- if (descriptors == nullptr) return nullptr;
- CHECK(index < descriptors->size());
+ auto file = GetInstance();
+ if (file == nullptr) return nullptr;
+ CHECK(index < file->controller_count_);
// Although the object is not actually an ACgroupController object, all ACgroupController_*
// functions implicitly convert ACgroupController* back to CgroupController* before invoking
// member functions.
- const CgroupController* p = std::next(descriptors->begin(), index)->second.controller();
- return static_cast<const ACgroupController*>(p);
+ return static_cast<ACgroupController*>(&file->controllers_[index]);
}
diff --git a/libprocessgroup/cgrouprc/cgrouprc_internal.h b/libprocessgroup/cgrouprc/cgrouprc_internal.h
index d517703..cd02f03 100644
--- a/libprocessgroup/cgrouprc/cgrouprc_internal.h
+++ b/libprocessgroup/cgrouprc/cgrouprc_internal.h
@@ -16,6 +16,9 @@
#pragma once
-#include <processgroup/cgroup_controller.h>
+#include <android/cgrouprc.h>
-struct ACgroupController : CgroupController {};
+#include <processgroup/format/cgroup_controller.h>
+#include <processgroup/format/cgroup_file.h>
+
+struct ACgroupController : android::cgrouprc::format::CgroupController {};
diff --git a/libprocessgroup/cgrouprc_format/Android.bp b/libprocessgroup/cgrouprc_format/Android.bp
index 6f9ab3e..0590924 100644
--- a/libprocessgroup/cgrouprc_format/Android.bp
+++ b/libprocessgroup/cgrouprc_format/Android.bp
@@ -23,4 +23,17 @@
vendor_ramdisk_available: true,
recovery_available: true,
native_bridge_supported: true,
+ srcs: [
+ "cgroup_controller.cpp",
+ ],
+ cflags: [
+ "-Wall",
+ "-Werror",
+ ],
+ export_include_dirs: [
+ "include",
+ ],
+ shared_libs: [
+ "libbase",
+ ],
}
diff --git a/libprocessgroup/util/cgroup_controller.cpp b/libprocessgroup/cgrouprc_format/cgroup_controller.cpp
similarity index 89%
rename from libprocessgroup/util/cgroup_controller.cpp
rename to libprocessgroup/cgrouprc_format/cgroup_controller.cpp
index fb41680..0dd909a 100644
--- a/libprocessgroup/util/cgroup_controller.cpp
+++ b/libprocessgroup/cgrouprc_format/cgroup_controller.cpp
@@ -14,9 +14,11 @@
* limitations under the License.
*/
-#include <processgroup/cgroup_controller.h>
+#include <processgroup/format/cgroup_controller.h>
-#include <cstring>
+namespace android {
+namespace cgrouprc {
+namespace format {
CgroupController::CgroupController(uint32_t version, uint32_t flags, const std::string& name,
const std::string& path, uint32_t max_activation_depth)
@@ -52,4 +54,8 @@
void CgroupController::set_flags(uint32_t flags) {
flags_ = flags;
-}
\ No newline at end of file
+}
+
+} // namespace format
+} // namespace cgrouprc
+} // namespace android
diff --git a/libprocessgroup/util/include/processgroup/cgroup_controller.h b/libprocessgroup/cgrouprc_format/include/processgroup/format/cgroup_controller.h
similarity index 86%
rename from libprocessgroup/util/include/processgroup/cgroup_controller.h
rename to libprocessgroup/cgrouprc_format/include/processgroup/format/cgroup_controller.h
index fe6a829..c0c1f60 100644
--- a/libprocessgroup/util/include/processgroup/cgroup_controller.h
+++ b/libprocessgroup/cgrouprc_format/include/processgroup/format/cgroup_controller.h
@@ -20,7 +20,11 @@
#include <cstdint>
#include <string>
-// Minimal controller description
+namespace android {
+namespace cgrouprc {
+namespace format {
+
+// Minimal controller description to be mmapped into process address space
struct CgroupController {
public:
CgroupController() = default;
@@ -44,4 +48,8 @@
uint32_t max_activation_depth_ = UINT32_MAX;
char name_[CGROUP_NAME_BUF_SZ] = {};
char path_[CGROUP_PATH_BUF_SZ] = {};
-};
\ No newline at end of file
+};
+
+} // namespace format
+} // namespace cgrouprc
+} // namespace android
diff --git a/libprocessgroup/cgrouprc_format/include/processgroup/format/cgroup_file.h b/libprocessgroup/cgrouprc_format/include/processgroup/format/cgroup_file.h
new file mode 100644
index 0000000..2d9786f
--- /dev/null
+++ b/libprocessgroup/cgrouprc_format/include/processgroup/format/cgroup_file.h
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+
+#pragma once
+
+#include <cstdint>
+
+#include <processgroup/format/cgroup_controller.h>
+
+namespace android {
+namespace cgrouprc {
+namespace format {
+
+struct CgroupFile {
+ uint32_t version_;
+ uint32_t controller_count_;
+ CgroupController controllers_[];
+
+ static constexpr uint32_t FILE_VERSION_1 = 1;
+ static constexpr uint32_t FILE_CURR_VERSION = FILE_VERSION_1;
+};
+
+} // namespace format
+} // namespace cgrouprc
+} // namespace android
diff --git a/libprocessgroup/include/processgroup/processgroup.h b/libprocessgroup/include/processgroup/processgroup.h
index 8057757..ffffeb4 100644
--- a/libprocessgroup/include/processgroup/processgroup.h
+++ b/libprocessgroup/include/processgroup/processgroup.h
@@ -57,7 +57,7 @@
bool SetProcessProfilesCached(uid_t uid, pid_t pid, const std::vector<std::string>& profiles);
-[[deprecated]] static constexpr const char* CGROUPS_RC_PATH = "/dev/cgroup_info/cgroup.rc";
+static constexpr const char* CGROUPS_RC_PATH = "/dev/cgroup_info/cgroup.rc";
bool UsePerAppMemcg();
diff --git a/libprocessgroup/internal.h b/libprocessgroup/internal.h
deleted file mode 100644
index ef85579..0000000
--- a/libprocessgroup/internal.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/*
- * Copyright (C) 2024 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.
- */
-
-#pragma once
-
-#include <string>
-
-static const std::string CGROUP_V2_ROOT_DEFAULT = "/sys/fs/cgroup";
\ No newline at end of file
diff --git a/libprocessgroup/setup/Android.bp b/libprocessgroup/setup/Android.bp
index cc6c67c..1a4ad01 100644
--- a/libprocessgroup/setup/Android.bp
+++ b/libprocessgroup/setup/Android.bp
@@ -33,6 +33,7 @@
"libjsoncpp",
],
static_libs: [
+ "libcgrouprc_format",
"libprocessgroup_util",
],
header_libs: [
diff --git a/libprocessgroup/setup/cgroup_descriptor.h b/libprocessgroup/setup/cgroup_descriptor.h
index 1afd2ee..06ce186 100644
--- a/libprocessgroup/setup/cgroup_descriptor.h
+++ b/libprocessgroup/setup/cgroup_descriptor.h
@@ -21,7 +21,10 @@
#include <sys/stat.h>
-#include <processgroup/cgroup_controller.h>
+#include <processgroup/format/cgroup_controller.h>
+
+namespace android {
+namespace cgrouprc {
// Complete controller description for mounting cgroups
class CgroupDescriptor {
@@ -30,7 +33,7 @@
mode_t mode, const std::string& uid, const std::string& gid, uint32_t flags,
uint32_t max_activation_depth);
- const CgroupController* controller() const { return &controller_; }
+ const format::CgroupController* controller() const { return &controller_; }
mode_t mode() const { return mode_; }
std::string uid() const { return uid_; }
std::string gid() const { return gid_; }
@@ -38,8 +41,11 @@
void set_mounted(bool mounted);
private:
- CgroupController controller_;
+ format::CgroupController controller_;
mode_t mode_ = 0;
std::string uid_;
std::string gid_;
};
+
+} // namespace cgrouprc
+} // namespace android
diff --git a/libprocessgroup/setup/cgroup_map_write.cpp b/libprocessgroup/setup/cgroup_map_write.cpp
index 8211680..bd41874 100644
--- a/libprocessgroup/setup/cgroup_map_write.cpp
+++ b/libprocessgroup/setup/cgroup_map_write.cpp
@@ -22,28 +22,45 @@
#include <fcntl.h>
#include <grp.h>
#include <pwd.h>
+#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
+#include <time.h>
#include <unistd.h>
#include <optional>
#include <android-base/file.h>
#include <android-base/logging.h>
-#include <processgroup/cgroup_descriptor.h>
+#include <android-base/properties.h>
+#include <android-base/stringprintf.h>
+#include <android-base/unique_fd.h>
+#include <android/cgrouprc.h>
+#include <json/reader.h>
+#include <json/value.h>
+#include <processgroup/format/cgroup_file.h>
#include <processgroup/processgroup.h>
#include <processgroup/setup.h>
#include <processgroup/util.h>
#include "../build_flags.h"
-#include "../internal.h"
+#include "cgroup_descriptor.h"
+
+using android::base::GetUintProperty;
+using android::base::StringPrintf;
+using android::base::unique_fd;
+
+namespace android {
+namespace cgrouprc {
static constexpr const char* CGROUPS_DESC_FILE = "/etc/cgroups.json";
static constexpr const char* CGROUPS_DESC_VENDOR_FILE = "/vendor/etc/cgroups.json";
static constexpr const char* TEMPLATE_CGROUPS_DESC_API_FILE = "/etc/task_profiles/cgroups_%u.json";
+static const std::string CGROUP_V2_ROOT_DEFAULT = "/sys/fs/cgroup";
+
static bool ChangeDirModeAndOwner(const std::string& path, mode_t mode, const std::string& uid,
const std::string& gid, bool permissive_mode = false) {
uid_t pw_uid = -1;
@@ -131,15 +148,149 @@
return true;
}
+static void MergeCgroupToDescriptors(std::map<std::string, CgroupDescriptor>* descriptors,
+ const Json::Value& cgroup, const std::string& name,
+ const std::string& root_path, int cgroups_version) {
+ const std::string cgroup_path = cgroup["Path"].asString();
+ std::string path;
+
+ if (!root_path.empty()) {
+ path = root_path;
+ if (cgroup_path != ".") {
+ path += "/";
+ path += cgroup_path;
+ }
+ } else {
+ path = cgroup_path;
+ }
+
+ uint32_t controller_flags = 0;
+
+ if (cgroup["NeedsActivation"].isBool() && cgroup["NeedsActivation"].asBool()) {
+ controller_flags |= CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION;
+ }
+
+ if (cgroup["Optional"].isBool() && cgroup["Optional"].asBool()) {
+ controller_flags |= CGROUPRC_CONTROLLER_FLAG_OPTIONAL;
+ }
+
+ uint32_t max_activation_depth = UINT32_MAX;
+ if (cgroup.isMember("MaxActivationDepth")) {
+ max_activation_depth = cgroup["MaxActivationDepth"].asUInt();
+ }
+
+ CgroupDescriptor descriptor(
+ cgroups_version, name, path, std::strtoul(cgroup["Mode"].asString().c_str(), 0, 8),
+ cgroup["UID"].asString(), cgroup["GID"].asString(), controller_flags,
+ max_activation_depth);
+
+ auto iter = descriptors->find(name);
+ if (iter == descriptors->end()) {
+ descriptors->emplace(name, descriptor);
+ } else {
+ iter->second = descriptor;
+ }
+}
+
+static const bool force_memcg_v2 = android::libprocessgroup_flags::force_memcg_v2();
+
+static bool ReadDescriptorsFromFile(const std::string& file_name,
+ std::map<std::string, CgroupDescriptor>* descriptors) {
+ std::vector<CgroupDescriptor> result;
+ std::string json_doc;
+
+ if (!android::base::ReadFileToString(file_name, &json_doc)) {
+ PLOG(ERROR) << "Failed to read task profiles from " << file_name;
+ return false;
+ }
+
+ Json::CharReaderBuilder builder;
+ std::unique_ptr<Json::CharReader> reader(builder.newCharReader());
+ Json::Value root;
+ std::string errorMessage;
+ if (!reader->parse(&*json_doc.begin(), &*json_doc.end(), &root, &errorMessage)) {
+ LOG(ERROR) << "Failed to parse cgroups description: " << errorMessage;
+ return false;
+ }
+
+ if (root.isMember("Cgroups")) {
+ const Json::Value& cgroups = root["Cgroups"];
+ for (Json::Value::ArrayIndex i = 0; i < cgroups.size(); ++i) {
+ std::string name = cgroups[i]["Controller"].asString();
+
+ if (force_memcg_v2 && name == "memory") continue;
+
+ MergeCgroupToDescriptors(descriptors, cgroups[i], name, "", 1);
+ }
+ }
+
+ bool memcgv2_present = false;
+ std::string root_path;
+ if (root.isMember("Cgroups2")) {
+ const Json::Value& cgroups2 = root["Cgroups2"];
+ root_path = cgroups2["Path"].asString();
+ MergeCgroupToDescriptors(descriptors, cgroups2, CGROUPV2_HIERARCHY_NAME, "", 2);
+
+ const Json::Value& childGroups = cgroups2["Controllers"];
+ for (Json::Value::ArrayIndex i = 0; i < childGroups.size(); ++i) {
+ std::string name = childGroups[i]["Controller"].asString();
+
+ if (force_memcg_v2 && name == "memory") memcgv2_present = true;
+
+ MergeCgroupToDescriptors(descriptors, childGroups[i], name, root_path, 2);
+ }
+ }
+
+ if (force_memcg_v2 && !memcgv2_present) {
+ LOG(INFO) << "Forcing memcg to v2 hierarchy";
+ Json::Value memcgv2;
+ memcgv2["Controller"] = "memory";
+ memcgv2["NeedsActivation"] = true;
+ memcgv2["Path"] = ".";
+ memcgv2["Optional"] = true; // In case of cgroup_disabled=memory, so we can still boot
+ MergeCgroupToDescriptors(descriptors, memcgv2, "memory",
+ root_path.empty() ? CGROUP_V2_ROOT_DEFAULT : root_path, 2);
+ }
+
+ return true;
+}
+
+static bool ReadDescriptors(std::map<std::string, CgroupDescriptor>* descriptors) {
+ // load system cgroup descriptors
+ if (!ReadDescriptorsFromFile(CGROUPS_DESC_FILE, descriptors)) {
+ return false;
+ }
+
+ // load API-level specific system cgroups descriptors if available
+ unsigned int api_level = GetUintProperty<unsigned int>("ro.product.first_api_level", 0);
+ if (api_level > 0) {
+ std::string api_cgroups_path =
+ android::base::StringPrintf(TEMPLATE_CGROUPS_DESC_API_FILE, api_level);
+ if (!access(api_cgroups_path.c_str(), F_OK) || errno != ENOENT) {
+ if (!ReadDescriptorsFromFile(api_cgroups_path, descriptors)) {
+ return false;
+ }
+ }
+ }
+
+ // load vendor cgroup descriptors if the file exists
+ if (!access(CGROUPS_DESC_VENDOR_FILE, F_OK) &&
+ !ReadDescriptorsFromFile(CGROUPS_DESC_VENDOR_FILE, descriptors)) {
+ return false;
+ }
+
+ return true;
+}
+
// To avoid issues in sdk_mac build
#if defined(__ANDROID__)
-static bool IsOptionalController(const CgroupController* controller) {
+static bool IsOptionalController(const format::CgroupController* controller) {
return controller->flags() & CGROUPRC_CONTROLLER_FLAG_OPTIONAL;
}
static bool MountV2CgroupController(const CgroupDescriptor& descriptor) {
- const CgroupController* controller = descriptor.controller();
+ const format::CgroupController* controller = descriptor.controller();
// /sys/fs/cgroup is created by cgroup2 with specific selinux permissions,
// try to create again in case the mount point is changed
@@ -173,7 +324,7 @@
}
static bool ActivateV2CgroupController(const CgroupDescriptor& descriptor) {
- const CgroupController* controller = descriptor.controller();
+ const format::CgroupController* controller = descriptor.controller();
if (!Mkdir(controller->path(), descriptor.mode(), descriptor.uid(), descriptor.gid())) {
LOG(ERROR) << "Failed to create directory for " << controller->name() << " cgroup";
@@ -187,7 +338,7 @@
std::string path = controller->path();
path += "/cgroup.subtree_control";
- if (!android::base::WriteStringToFile(str, path)) {
+ if (!base::WriteStringToFile(str, path)) {
if (IsOptionalController(controller)) {
PLOG(INFO) << "Failed to activate optional controller " << controller->name()
<< " at " << path;
@@ -202,7 +353,7 @@
}
static bool MountV1CgroupController(const CgroupDescriptor& descriptor) {
- const CgroupController* controller = descriptor.controller();
+ const format::CgroupController* controller = descriptor.controller();
// mkdir <path> [mode] [owner] [group]
if (!Mkdir(controller->path(), descriptor.mode(), descriptor.uid(), descriptor.gid())) {
@@ -237,7 +388,7 @@
}
static bool SetupCgroup(const CgroupDescriptor& descriptor) {
- const CgroupController* controller = descriptor.controller();
+ const format::CgroupController* controller = descriptor.controller();
if (controller->version() == 2) {
if (!strcmp(controller->name(), CGROUPV2_HIERARCHY_NAME)) {
@@ -259,6 +410,35 @@
#endif
+static bool WriteRcFile(const std::map<std::string, CgroupDescriptor>& descriptors) {
+ unique_fd fd(TEMP_FAILURE_RETRY(open(CGROUPS_RC_PATH, O_CREAT | O_WRONLY | O_TRUNC | O_CLOEXEC,
+ S_IRUSR | S_IRGRP | S_IROTH)));
+ if (fd < 0) {
+ PLOG(ERROR) << "open() failed for " << CGROUPS_RC_PATH;
+ return false;
+ }
+
+ format::CgroupFile fl;
+ fl.version_ = format::CgroupFile::FILE_CURR_VERSION;
+ fl.controller_count_ = descriptors.size();
+ int ret = TEMP_FAILURE_RETRY(write(fd, &fl, sizeof(fl)));
+ if (ret < 0) {
+ PLOG(ERROR) << "write() failed for " << CGROUPS_RC_PATH;
+ return false;
+ }
+
+ for (const auto& [name, descriptor] : descriptors) {
+ ret = TEMP_FAILURE_RETRY(
+ write(fd, descriptor.controller(), sizeof(format::CgroupController)));
+ if (ret < 0) {
+ PLOG(ERROR) << "write() failed for " << CGROUPS_RC_PATH;
+ return false;
+ }
+ }
+
+ return true;
+}
+
CgroupDescriptor::CgroupDescriptor(uint32_t version, const std::string& name,
const std::string& path, mode_t mode, const std::string& uid,
const std::string& gid, uint32_t flags,
@@ -278,6 +458,9 @@
controller_.set_flags(flags);
}
+} // namespace cgrouprc
+} // namespace android
+
static std::optional<bool> MGLRUDisabled() {
const std::string file_name = "/sys/kernel/mm/lru_gen/enabled";
std::string content;
@@ -289,8 +472,9 @@
return content == "0x0000";
}
-static std::optional<bool> MEMCGDisabled(const CgroupDescriptorMap& descriptors) {
- std::string cgroup_v2_root = CGROUP_V2_ROOT_DEFAULT;
+static std::optional<bool> MEMCGDisabled(
+ const std::map<std::string, android::cgrouprc::CgroupDescriptor>& descriptors) {
+ std::string cgroup_v2_root = android::cgrouprc::CGROUP_V2_ROOT_DEFAULT;
const auto it = descriptors.find(CGROUPV2_HIERARCHY_NAME);
if (it == descriptors.end()) {
LOG(WARNING) << "No Cgroups2 path found in cgroups.json. Vendor has modified Android, and "
@@ -311,10 +495,14 @@
return content.find("memory") == std::string::npos;
}
-static bool CreateV2SubHierarchy(const std::string& path, const CgroupDescriptorMap& descriptors) {
+static bool CreateV2SubHierarchy(
+ const std::string& path,
+ const std::map<std::string, android::cgrouprc::CgroupDescriptor>& descriptors) {
+ using namespace android::cgrouprc;
+
const auto cgv2_iter = descriptors.find(CGROUPV2_HIERARCHY_NAME);
if (cgv2_iter == descriptors.end()) return false;
- const CgroupDescriptor cgv2_descriptor = cgv2_iter->second;
+ const android::cgrouprc::CgroupDescriptor cgv2_descriptor = cgv2_iter->second;
if (!Mkdir(path, cgv2_descriptor.mode(), cgv2_descriptor.uid(), cgv2_descriptor.gid())) {
PLOG(ERROR) << "Failed to create directory for " << path;
@@ -324,10 +512,10 @@
// Activate all v2 controllers in path so they can be activated in
// children as they are created.
for (const auto& [name, descriptor] : descriptors) {
- const CgroupController* controller = descriptor.controller();
+ const format::CgroupController* controller = descriptor.controller();
std::uint32_t flags = controller->flags();
std::uint32_t max_activation_depth = controller->max_activation_depth();
- const int depth = GetCgroupDepth(controller->path(), path);
+ const int depth = util::GetCgroupDepth(controller->path(), path);
if (controller->version() == 2 && name != CGROUPV2_HIERARCHY_NAME &&
flags & CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION && depth < max_activation_depth) {
@@ -347,13 +535,22 @@
}
bool CgroupSetup() {
- CgroupDescriptorMap descriptors;
+ using namespace android::cgrouprc;
+
+ std::map<std::string, CgroupDescriptor> descriptors;
if (getpid() != 1) {
LOG(ERROR) << "Cgroup setup can be done only by init process";
return false;
}
+ // Make sure we do this only one time. No need for std::call_once because
+ // init is a single-threaded process
+ if (access(CGROUPS_RC_PATH, F_OK) == 0) {
+ LOG(WARNING) << "Attempt to call CgroupSetup() more than once";
+ return true;
+ }
+
// load cgroups.json file
if (!ReadDescriptors(&descriptors)) {
LOG(ERROR) << "Failed to load cgroup description file";
@@ -362,18 +559,15 @@
// setup cgroups
for (auto& [name, descriptor] : descriptors) {
- if (descriptor.controller()->flags() & CGROUPRC_CONTROLLER_FLAG_MOUNTED) {
- LOG(WARNING) << "Attempt to call CgroupSetup() more than once";
- return true;
- }
-
- if (!SetupCgroup(descriptor)) {
+ if (SetupCgroup(descriptor)) {
+ descriptor.set_mounted(true);
+ } else {
// issue a warning and proceed with the next cgroup
LOG(WARNING) << "Failed to setup " << name << " cgroup";
}
}
- if (android::libprocessgroup_flags::force_memcg_v2()) {
+ if (force_memcg_v2) {
if (MGLRUDisabled().value_or(false)) {
LOG(WARNING) << "Memcg forced to v2 hierarchy with MGLRU disabled! "
<< "Global reclaim performance will suffer.";
@@ -399,5 +593,26 @@
}
}
+ // mkdir <CGROUPS_RC_DIR> 0711 system system
+ if (!Mkdir(android::base::Dirname(CGROUPS_RC_PATH), 0711, "system", "system")) {
+ LOG(ERROR) << "Failed to create directory for " << CGROUPS_RC_PATH << " file";
+ return false;
+ }
+
+ // Generate <CGROUPS_RC_FILE> file which can be directly mmapped into
+ // process memory. This optimizes performance, memory usage
+ // and limits infrormation shared with unprivileged processes
+ // to the minimum subset of information from cgroups.json
+ if (!WriteRcFile(descriptors)) {
+ LOG(ERROR) << "Failed to write " << CGROUPS_RC_PATH << " file";
+ return false;
+ }
+
+ // chmod 0644 <CGROUPS_RC_PATH>
+ if (fchmodat(AT_FDCWD, CGROUPS_RC_PATH, 0644, AT_SYMLINK_NOFOLLOW) < 0) {
+ PLOG(ERROR) << "fchmodat() failed";
+ return false;
+ }
+
return true;
}
diff --git a/libprocessgroup/util/Android.bp b/libprocessgroup/util/Android.bp
index 1c74d4e..54ba69b 100644
--- a/libprocessgroup/util/Android.bp
+++ b/libprocessgroup/util/Android.bp
@@ -37,16 +37,8 @@
"include",
],
srcs: [
- "cgroup_controller.cpp",
- "cgroup_descriptor.cpp",
"util.cpp",
],
- shared_libs: [
- "libbase",
- ],
- static_libs: [
- "libjsoncpp",
- ],
defaults: ["libprocessgroup_build_flags_cc"],
}
diff --git a/libprocessgroup/util/cgroup_descriptor.cpp b/libprocessgroup/util/cgroup_descriptor.cpp
deleted file mode 100644
index 4d3347f..0000000
--- a/libprocessgroup/util/cgroup_descriptor.cpp
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- * Copyright (C) 2024 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 <processgroup/cgroup_descriptor.h>
-
-#include <processgroup/util.h> // For flag values
-
-CgroupDescriptor::CgroupDescriptor(uint32_t version, const std::string& name,
- const std::string& path, mode_t mode, const std::string& uid,
- const std::string& gid, uint32_t flags,
- uint32_t max_activation_depth)
- : controller_(version, flags, name, path, max_activation_depth),
- mode_(mode),
- uid_(uid),
- gid_(gid) {}
-
-void CgroupDescriptor::set_mounted(bool mounted) {
- uint32_t flags = controller_.flags();
- if (mounted) {
- flags |= CGROUPRC_CONTROLLER_FLAG_MOUNTED;
- } else {
- flags &= ~CGROUPRC_CONTROLLER_FLAG_MOUNTED;
- }
- controller_.set_flags(flags);
-}
diff --git a/libprocessgroup/util/include/processgroup/cgroup_descriptor.h b/libprocessgroup/util/include/processgroup/cgroup_descriptor.h
deleted file mode 100644
index 1afd2ee..0000000
--- a/libprocessgroup/util/include/processgroup/cgroup_descriptor.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
- * Copyright (C) 2019 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.
- */
-
-#pragma once
-
-#include <cstdint>
-#include <string>
-
-#include <sys/stat.h>
-
-#include <processgroup/cgroup_controller.h>
-
-// Complete controller description for mounting cgroups
-class CgroupDescriptor {
- public:
- CgroupDescriptor(uint32_t version, const std::string& name, const std::string& path,
- mode_t mode, const std::string& uid, const std::string& gid, uint32_t flags,
- uint32_t max_activation_depth);
-
- const CgroupController* controller() const { return &controller_; }
- mode_t mode() const { return mode_; }
- std::string uid() const { return uid_; }
- std::string gid() const { return gid_; }
-
- void set_mounted(bool mounted);
-
- private:
- CgroupController controller_;
- mode_t mode_ = 0;
- std::string uid_;
- std::string gid_;
-};
diff --git a/libprocessgroup/util/include/processgroup/util.h b/libprocessgroup/util/include/processgroup/util.h
index d592a63..8d013af 100644
--- a/libprocessgroup/util/include/processgroup/util.h
+++ b/libprocessgroup/util/include/processgroup/util.h
@@ -16,18 +16,10 @@
#pragma once
-#include <map>
#include <string>
-#include "cgroup_descriptor.h"
-
-// Duplicated from cgrouprc.h. Don't depend on libcgrouprc here.
-#define CGROUPRC_CONTROLLER_FLAG_MOUNTED 0x1
-#define CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION 0x2
-#define CGROUPRC_CONTROLLER_FLAG_OPTIONAL 0x4
+namespace util {
unsigned int GetCgroupDepth(const std::string& controller_root, const std::string& cgroup_path);
-using CgroupControllerName = std::string;
-using CgroupDescriptorMap = std::map<CgroupControllerName, CgroupDescriptor>;
-bool ReadDescriptors(CgroupDescriptorMap* descriptors);
+} // namespace util
diff --git a/libprocessgroup/util/tests/util.cpp b/libprocessgroup/util/tests/util.cpp
index 6caef8e..1de7d6f 100644
--- a/libprocessgroup/util/tests/util.cpp
+++ b/libprocessgroup/util/tests/util.cpp
@@ -18,6 +18,8 @@
#include "gtest/gtest.h"
+using util::GetCgroupDepth;
+
TEST(EmptyInputs, bothEmpty) {
EXPECT_EQ(GetCgroupDepth({}, {}), 0);
}
diff --git a/libprocessgroup/util/util.cpp b/libprocessgroup/util/util.cpp
index bff4c6f..9b88a22 100644
--- a/libprocessgroup/util/util.cpp
+++ b/libprocessgroup/util/util.cpp
@@ -18,33 +18,9 @@
#include <algorithm>
#include <iterator>
-#include <optional>
-#include <string_view>
-
-#include <mntent.h>
-
-#include <android-base/file.h>
-#include <android-base/logging.h>
-#include <android-base/properties.h>
-#include <android-base/stringprintf.h>
-#include <json/reader.h>
-#include <json/value.h>
-
-#include "../build_flags.h"
-#include "../internal.h"
-
-using android::base::GetUintProperty;
namespace {
-constexpr const char* CGROUPS_DESC_FILE = "/etc/cgroups.json";
-constexpr const char* CGROUPS_DESC_VENDOR_FILE = "/vendor/etc/cgroups.json";
-constexpr const char* TEMPLATE_CGROUPS_DESC_API_FILE = "/etc/task_profiles/cgroups_%u.json";
-
-// This should match the publicly declared value in processgroup.h,
-// but we don't want this library to depend on libprocessgroup.
-constexpr std::string CGROUPV2_HIERARCHY_NAME_INTERNAL = "cgroup2";
-
const char SEP = '/';
std::string DeduplicateAndTrimSeparators(const std::string& path) {
@@ -66,135 +42,9 @@
return ret;
}
-void MergeCgroupToDescriptors(CgroupDescriptorMap* descriptors, const Json::Value& cgroup,
- const std::string& name, const std::string& root_path,
- int cgroups_version) {
- const std::string cgroup_path = cgroup["Path"].asString();
- std::string path;
-
- if (!root_path.empty()) {
- path = root_path;
- if (cgroup_path != ".") {
- path += "/";
- path += cgroup_path;
- }
- } else {
- path = cgroup_path;
- }
-
- uint32_t controller_flags = 0;
-
- if (cgroup["NeedsActivation"].isBool() && cgroup["NeedsActivation"].asBool()) {
- controller_flags |= CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION;
- }
-
- if (cgroup["Optional"].isBool() && cgroup["Optional"].asBool()) {
- controller_flags |= CGROUPRC_CONTROLLER_FLAG_OPTIONAL;
- }
-
- uint32_t max_activation_depth = UINT32_MAX;
- if (cgroup.isMember("MaxActivationDepth")) {
- max_activation_depth = cgroup["MaxActivationDepth"].asUInt();
- }
-
- CgroupDescriptor descriptor(
- cgroups_version, name, path, std::strtoul(cgroup["Mode"].asString().c_str(), 0, 8),
- cgroup["UID"].asString(), cgroup["GID"].asString(), controller_flags,
- max_activation_depth);
-
- auto iter = descriptors->find(name);
- if (iter == descriptors->end()) {
- descriptors->emplace(name, descriptor);
- } else {
- iter->second = descriptor;
- }
-}
-
-bool ReadDescriptorsFromFile(const std::string& file_name, CgroupDescriptorMap* descriptors) {
- static constexpr bool force_memcg_v2 = android::libprocessgroup_flags::force_memcg_v2();
- std::vector<CgroupDescriptor> result;
- std::string json_doc;
-
- if (!android::base::ReadFileToString(file_name, &json_doc)) {
- PLOG(ERROR) << "Failed to read task profiles from " << file_name;
- return false;
- }
-
- Json::CharReaderBuilder builder;
- std::unique_ptr<Json::CharReader> reader(builder.newCharReader());
- Json::Value root;
- std::string errorMessage;
- if (!reader->parse(&*json_doc.begin(), &*json_doc.end(), &root, &errorMessage)) {
- LOG(ERROR) << "Failed to parse cgroups description: " << errorMessage;
- return false;
- }
-
- if (root.isMember("Cgroups")) {
- const Json::Value& cgroups = root["Cgroups"];
- for (Json::Value::ArrayIndex i = 0; i < cgroups.size(); ++i) {
- std::string name = cgroups[i]["Controller"].asString();
-
- if (force_memcg_v2 && name == "memory") continue;
-
- MergeCgroupToDescriptors(descriptors, cgroups[i], name, "", 1);
- }
- }
-
- bool memcgv2_present = false;
- std::string root_path;
- if (root.isMember("Cgroups2")) {
- const Json::Value& cgroups2 = root["Cgroups2"];
- root_path = cgroups2["Path"].asString();
- MergeCgroupToDescriptors(descriptors, cgroups2, CGROUPV2_HIERARCHY_NAME_INTERNAL, "", 2);
-
- const Json::Value& childGroups = cgroups2["Controllers"];
- for (Json::Value::ArrayIndex i = 0; i < childGroups.size(); ++i) {
- std::string name = childGroups[i]["Controller"].asString();
-
- if (force_memcg_v2 && name == "memory") memcgv2_present = true;
-
- MergeCgroupToDescriptors(descriptors, childGroups[i], name, root_path, 2);
- }
- }
-
- if (force_memcg_v2 && !memcgv2_present) {
- LOG(INFO) << "Forcing memcg to v2 hierarchy";
- Json::Value memcgv2;
- memcgv2["Controller"] = "memory";
- memcgv2["NeedsActivation"] = true;
- memcgv2["Path"] = ".";
- memcgv2["Optional"] = true; // In case of cgroup_disabled=memory, so we can still boot
- MergeCgroupToDescriptors(descriptors, memcgv2, "memory",
- root_path.empty() ? CGROUP_V2_ROOT_DEFAULT : root_path, 2);
- }
-
- return true;
-}
-
-using MountDir = std::string;
-using MountOpts = std::string;
-static std::optional<std::map<MountDir, MountOpts>> ReadCgroupV1Mounts() {
- FILE* fp = setmntent("/proc/mounts", "r");
- if (fp == nullptr) {
- PLOG(ERROR) << "Failed to read mounts";
- return std::nullopt;
- }
-
- std::map<MountDir, MountOpts> mounts;
- const std::string_view CGROUP_V1_TYPE = "cgroup";
- for (mntent* mentry = getmntent(fp); mentry != nullptr; mentry = getmntent(fp)) {
- if (mentry->mnt_type && CGROUP_V1_TYPE == mentry->mnt_type &&
- mentry->mnt_dir && mentry->mnt_opts) {
- mounts[mentry->mnt_dir] = mentry->mnt_opts;
- }
- }
- endmntent(fp);
-
- return mounts;
-}
-
} // anonymous namespace
+namespace util {
unsigned int GetCgroupDepth(const std::string& controller_root, const std::string& cgroup_path) {
const std::string deduped_root = DeduplicateAndTrimSeparators(controller_root);
@@ -206,47 +56,4 @@
return std::count(deduped_path.begin() + deduped_root.size(), deduped_path.end(), SEP);
}
-bool ReadDescriptors(CgroupDescriptorMap* descriptors) {
- // load system cgroup descriptors
- if (!ReadDescriptorsFromFile(CGROUPS_DESC_FILE, descriptors)) {
- return false;
- }
-
- // load API-level specific system cgroups descriptors if available
- unsigned int api_level = GetUintProperty<unsigned int>("ro.product.first_api_level", 0);
- if (api_level > 0) {
- std::string api_cgroups_path =
- android::base::StringPrintf(TEMPLATE_CGROUPS_DESC_API_FILE, api_level);
- if (!access(api_cgroups_path.c_str(), F_OK) || errno != ENOENT) {
- if (!ReadDescriptorsFromFile(api_cgroups_path, descriptors)) {
- return false;
- }
- }
- }
-
- // load vendor cgroup descriptors if the file exists
- if (!access(CGROUPS_DESC_VENDOR_FILE, F_OK) &&
- !ReadDescriptorsFromFile(CGROUPS_DESC_VENDOR_FILE, descriptors)) {
- return false;
- }
-
- // check for v1 mount/usability status
- std::optional<std::map<MountDir, MountOpts>> v1Mounts;
- for (auto& [name, descriptor] : *descriptors) {
- const CgroupController* const controller = descriptor.controller();
-
- if (controller->version() != 1) continue;
-
- // Read only once, and only if we have at least one v1 controller
- if (!v1Mounts) {
- v1Mounts = ReadCgroupV1Mounts();
- if (!v1Mounts) return false;
- }
-
- if (const auto it = v1Mounts->find(controller->path()); it != v1Mounts->end()) {
- if (it->second.contains(controller->name())) descriptor.set_mounted(true);
- }
- }
-
- return true;
-}
+} // namespace util