Merge changes from topic "memcg_v2_soong_flags" into main
* changes:
Add build flag to split the cgroup v2 hierarchy into apps/system
Add build flag to force memcg to the v2 cgroup hierarchy
Use ConvertUid{Pid}ToPath for all path generation
Fix unused params and remove unneeded cflags
diff --git a/libprocessgroup/Android.bp b/libprocessgroup/Android.bp
index c6a0737..bb855d5 100644
--- a/libprocessgroup/Android.bp
+++ b/libprocessgroup/Android.bp
@@ -2,15 +2,34 @@
default_applicable_licenses: ["Android-Apache-2.0"],
}
-cc_defaults {
- name: "libprocessgroup_defaults",
- cpp_std: "gnu++20",
- cflags: [
- "-Wall",
- "-Werror",
- "-Wexit-time-destructors",
- "-Wno-unused-parameter",
+soong_config_module_type {
+ name: "libprocessgroup_flag_aware_cc_defaults",
+ module_type: "cc_defaults",
+ config_namespace: "ANDROID",
+ bool_variables: [
+ "memcg_v2_force_enabled",
+ "cgroup_v2_sys_app_isolation",
],
+ properties: [
+ "cflags",
+ ],
+}
+
+libprocessgroup_flag_aware_cc_defaults {
+ name: "libprocessgroup_build_flags_cc",
+ cpp_std: "gnu++20",
+ soong_config_variables: {
+ memcg_v2_force_enabled: {
+ cflags: [
+ "-DMEMCG_V2_FORCE_ENABLED=true",
+ ],
+ },
+ cgroup_v2_sys_app_isolation: {
+ cflags: [
+ "-DCGROUP_V2_SYS_APP_ISOLATION=true",
+ ],
+ },
+ },
}
cc_library_headers {
@@ -73,7 +92,7 @@
export_header_lib_headers: [
"libprocessgroup_headers",
],
- defaults: ["libprocessgroup_defaults"],
+ defaults: ["libprocessgroup_build_flags_cc"],
apex_available: [
"//apex_available:platform",
"//apex_available:anyapex",
@@ -84,7 +103,7 @@
cc_test {
name: "task_profiles_test",
host_supported: true,
- defaults: ["libprocessgroup_defaults"],
+ defaults: ["libprocessgroup_build_flags_cc"],
srcs: [
"task_profiles_test.cpp",
],
diff --git a/libprocessgroup/build_flags.h b/libprocessgroup/build_flags.h
new file mode 100644
index 0000000..bc3e7df
--- /dev/null
+++ b/libprocessgroup/build_flags.h
@@ -0,0 +1,37 @@
+/*
+ * 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
+
+#ifndef MEMCG_V2_FORCE_ENABLED
+#define MEMCG_V2_FORCE_ENABLED false
+#endif
+
+#ifndef CGROUP_V2_SYS_APP_ISOLATION
+#define CGROUP_V2_SYS_APP_ISOLATION false
+#endif
+
+namespace android::libprocessgroup_flags {
+
+inline consteval bool force_memcg_v2() {
+ return MEMCG_V2_FORCE_ENABLED;
+}
+
+inline consteval bool cgroup_v2_sys_app_isolation() {
+ return CGROUP_V2_SYS_APP_ISOLATION;
+}
+
+} // namespace android::libprocessgroup_flags
diff --git a/libprocessgroup/processgroup.cpp b/libprocessgroup/processgroup.cpp
index 94d9502..8df2805 100644
--- a/libprocessgroup/processgroup.cpp
+++ b/libprocessgroup/processgroup.cpp
@@ -78,14 +78,6 @@
return true;
}
-static std::string ConvertUidToPath(const char* cgroup, uid_t uid) {
- return StringPrintf("%s/uid_%u", cgroup, uid);
-}
-
-static std::string ConvertUidPidToPath(const char* cgroup, uid_t uid, pid_t pid) {
- return StringPrintf("%s/uid_%u/pid_%d", cgroup, uid, pid);
-}
-
static bool CgroupKillAvailable() {
static std::once_flag f;
static bool cgroup_kill_available = false;
diff --git a/libprocessgroup/setup/Android.bp b/libprocessgroup/setup/Android.bp
index ea6c247..1e0783a 100644
--- a/libprocessgroup/setup/Android.bp
+++ b/libprocessgroup/setup/Android.bp
@@ -41,8 +41,5 @@
export_header_lib_headers: [
"libprocessgroup_headers",
],
- cflags: [
- "-Wall",
- "-Werror",
- ],
+ defaults: ["libprocessgroup_build_flags_cc"],
}
diff --git a/libprocessgroup/setup/cgroup_map_write.cpp b/libprocessgroup/setup/cgroup_map_write.cpp
index 4e44c91..1b26fbc 100644
--- a/libprocessgroup/setup/cgroup_map_write.cpp
+++ b/libprocessgroup/setup/cgroup_map_write.cpp
@@ -29,7 +29,7 @@
#include <time.h>
#include <unistd.h>
-#include <regex>
+#include <optional>
#include <android-base/file.h>
#include <android-base/logging.h>
@@ -43,6 +43,7 @@
#include <processgroup/processgroup.h>
#include <processgroup/setup.h>
+#include "../build_flags.h"
#include "cgroup_descriptor.h"
using android::base::GetUintProperty;
@@ -57,6 +58,8 @@
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;
@@ -182,6 +185,8 @@
}
}
+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;
@@ -205,22 +210,41 @@
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"];
- std::string root_path = cgroups2["Path"].asString();
+ 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;
}
@@ -308,7 +332,8 @@
if (!base::WriteStringToFile(str, path)) {
if (IsOptionalController(controller)) {
- PLOG(INFO) << "Failed to activate optional controller " << controller->name();
+ PLOG(INFO) << "Failed to activate optional controller " << controller->name()
+ << " at " << path;
return true;
}
PLOG(ERROR) << "Failed to activate controller " << controller->name();
@@ -424,6 +449,76 @@
} // namespace cgrouprc
} // namespace android
+static std::optional<bool> MGLRUDisabled() {
+ const std::string file_name = "/sys/kernel/mm/lru_gen/enabled";
+ std::string content;
+ if (!android::base::ReadFileToString(file_name, &content)) {
+ PLOG(ERROR) << "Failed to read MGLRU state from " << file_name;
+ return {};
+ }
+
+ return content == "0x0000";
+}
+
+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 "
+ << "kernel memory use will be higher than intended.";
+ } else if (it->second.controller()->path() != cgroup_v2_root) {
+ cgroup_v2_root = it->second.controller()->path();
+ }
+
+ const std::string file_name = cgroup_v2_root + "/cgroup.controllers";
+ std::string content;
+ if (!android::base::ReadFileToString(file_name, &content)) {
+ PLOG(ERROR) << "Failed to read cgroup controllers from " << file_name;
+ return {};
+ }
+
+ // If we've forced memcg to v2 and it's not available, then it could only have been disabled
+ // on the kernel command line (GKI sets CONFIG_MEMCG).
+ return content.find("memory") == std::string::npos;
+}
+
+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 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;
+ return false;
+ }
+
+ // Activate all v2 controllers in path so they can be activated in
+ // children as they are created.
+ for (const auto& [name, descriptor] : descriptors) {
+ const format::CgroupController* controller = descriptor.controller();
+ std::uint32_t flags = controller->flags();
+ if (controller->version() == 2 && name != CGROUPV2_HIERARCHY_NAME &&
+ flags & CGROUPRC_CONTROLLER_FLAG_NEEDS_ACTIVATION) {
+ std::string str("+");
+ str += controller->name();
+ if (!android::base::WriteStringToFile(str, path + "/cgroup.subtree_control")) {
+ if (flags & CGROUPRC_CONTROLLER_FLAG_OPTIONAL) {
+ PLOG(WARNING) << "Activation of cgroup controller " << str << " failed in path "
+ << path;
+ } else {
+ return false;
+ }
+ }
+ }
+ }
+ return true;
+}
+
bool CgroupSetup() {
using namespace android::cgrouprc;
@@ -457,6 +552,32 @@
}
}
+ if (force_memcg_v2) {
+ if (MGLRUDisabled().value_or(false)) {
+ LOG(WARNING) << "Memcg forced to v2 hierarchy with MGLRU disabled! "
+ << "Global reclaim performance will suffer.";
+ }
+ if (MEMCGDisabled(descriptors).value_or(false)) {
+ LOG(WARNING) << "Memcg forced to v2 hierarchy while memcg is disabled by kernel "
+ << "command line!";
+ }
+ }
+
+ // System / app isolation.
+ // This really belongs in early-init in init.rc, but we cannot use the flag there.
+ if (android::libprocessgroup_flags::cgroup_v2_sys_app_isolation()) {
+ const auto it = descriptors.find(CGROUPV2_HIERARCHY_NAME);
+ const std::string cgroup_v2_root = (it == descriptors.end())
+ ? CGROUP_V2_ROOT_DEFAULT
+ : it->second.controller()->path();
+
+ LOG(INFO) << "Using system/app isolation under: " << cgroup_v2_root;
+ if (!CreateV2SubHierarchy(cgroup_v2_root + "/apps", descriptors) ||
+ !CreateV2SubHierarchy(cgroup_v2_root + "/system", descriptors)) {
+ return false;
+ }
+ }
+
// 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";
diff --git a/libprocessgroup/task_profiles.cpp b/libprocessgroup/task_profiles.cpp
index 2353cf1..0c2252b 100644
--- a/libprocessgroup/task_profiles.cpp
+++ b/libprocessgroup/task_profiles.cpp
@@ -33,6 +33,8 @@
#include <json/reader.h>
#include <json/value.h>
+#include <build_flags.h>
+
// To avoid issues in sdk_mac build
#if defined(__ANDROID__)
#include <sys/prctl.h>
@@ -126,11 +128,29 @@
file_v2_name_ = file_v2_name;
}
+static bool isSystemApp(uid_t uid) {
+ return uid < AID_APP_START;
+}
+
+std::string ConvertUidToPath(const char* root_cgroup_path, uid_t uid) {
+ if (android::libprocessgroup_flags::cgroup_v2_sys_app_isolation()) {
+ if (isSystemApp(uid))
+ return StringPrintf("%s/system/uid_%u", root_cgroup_path, uid);
+ else
+ return StringPrintf("%s/apps/uid_%u", root_cgroup_path, uid);
+ }
+ return StringPrintf("%s/uid_%u", root_cgroup_path, uid);
+}
+
+std::string ConvertUidPidToPath(const char* root_cgroup_path, uid_t uid, pid_t pid) {
+ const std::string uid_path = ConvertUidToPath(root_cgroup_path, uid);
+ return StringPrintf("%s/pid_%d", uid_path.c_str(), pid);
+}
+
bool ProfileAttribute::GetPathForProcess(uid_t uid, pid_t pid, std::string* path) const {
if (controller()->version() == 2) {
- // all cgroup v2 attributes use the same process group hierarchy
- *path = StringPrintf("%s/uid_%u/pid_%d/%s", controller()->path(), uid, pid,
- file_name().c_str());
+ const std::string cgroup_path = ConvertUidPidToPath(controller()->path(), uid, pid);
+ *path = cgroup_path + "/" + file_name();
return true;
}
return GetPathForTask(pid, path);
@@ -155,12 +175,14 @@
return true;
}
+// NOTE: This function is for cgroup v2 only
bool ProfileAttribute::GetPathForUID(uid_t uid, std::string* path) const {
if (path == nullptr) {
return true;
}
- *path = StringPrintf("%s/uid_%u/%s", controller()->path(), uid, file_name().c_str());
+ const std::string cgroup_path = ConvertUidToPath(controller()->path(), uid);
+ *path = cgroup_path + "/" + file_name();
return true;
}
diff --git a/libprocessgroup/task_profiles.h b/libprocessgroup/task_profiles.h
index 2fa1931..7e3c50d 100644
--- a/libprocessgroup/task_profiles.h
+++ b/libprocessgroup/task_profiles.h
@@ -82,8 +82,8 @@
virtual void EnableResourceCaching(ResourceCacheType) {}
virtual void DropResourceCaching(ResourceCacheType) {}
- virtual bool IsValidForProcess(uid_t uid, pid_t pid) const { return false; }
- virtual bool IsValidForTask(pid_t tid) const { return false; }
+ virtual bool IsValidForProcess(uid_t, pid_t) const { return false; }
+ virtual bool IsValidForTask(pid_t) const { return false; }
protected:
enum CacheUseResult { SUCCESS, FAIL, UNUSED };
@@ -109,8 +109,8 @@
const char* Name() const override { return "SetTimerSlack"; }
bool ExecuteForTask(pid_t tid) const override;
- bool IsValidForProcess(uid_t uid, pid_t pid) const override { return true; }
- bool IsValidForTask(pid_t tid) const override { return true; }
+ bool IsValidForProcess(uid_t, pid_t) const override { return true; }
+ bool IsValidForTask(pid_t) const override { return true; }
private:
unsigned long slack_;
@@ -252,3 +252,6 @@
std::map<std::string, std::shared_ptr<TaskProfile>, std::less<>> profiles_;
std::map<std::string, std::unique_ptr<IProfileAttribute>, std::less<>> attributes_;
};
+
+std::string ConvertUidToPath(const char* root_cgroup_path, uid_t uid);
+std::string ConvertUidPidToPath(const char* root_cgroup_path, uid_t uid, pid_t pid);
diff --git a/libprocessgroup/task_profiles_test.cpp b/libprocessgroup/task_profiles_test.cpp
index b17e695..d19da2b 100644
--- a/libprocessgroup/task_profiles_test.cpp
+++ b/libprocessgroup/task_profiles_test.cpp
@@ -102,8 +102,7 @@
public:
ProfileAttributeMock(const std::string& file_name) : file_name_(file_name) {}
~ProfileAttributeMock() override = default;
- void Reset(const CgroupController& controller, const std::string& file_name,
- const std::string& file_v2_name) override {
+ void Reset(const CgroupController&, const std::string&, const std::string&) override {
CHECK(false);
}
const CgroupController* controller() const override {
@@ -111,10 +110,10 @@
return {};
}
const std::string& file_name() const override { return file_name_; }
- bool GetPathForProcess(uid_t uid, pid_t pid, std::string* path) const override {
+ bool GetPathForProcess(uid_t, pid_t pid, std::string* path) const override {
return GetPathForTask(pid, path);
}
- bool GetPathForTask(int tid, std::string* path) const override {
+ bool GetPathForTask(int, std::string* path) const override {
#ifdef __ANDROID__
CHECK(CgroupGetControllerPath(CGROUPV2_HIERARCHY_NAME, path));
CHECK_GT(path->length(), 0);