Merge "Add cpuset switching to scheduler policy mechanism." into oc-mr1-dev
diff --git a/services/vr/performanced/performance_service.cpp b/services/vr/performanced/performance_service.cpp
index 4b9fbe0..4c26671 100644
--- a/services/vr/performanced/performance_service.cpp
+++ b/services/vr/performanced/performance_service.cpp
@@ -22,13 +22,15 @@
 using android::pdx::ErrorStatus;
 using android::pdx::Message;
 using android::pdx::Status;
-using android::pdx::rpc::DispatchRemoteMethod;
 using android::pdx::default_transport::Endpoint;
+using android::pdx::rpc::DispatchRemoteMethod;
 
 namespace {
 
 const char kCpuSetBasePath[] = "/dev/cpuset";
 
+const char kRootCpuSet[] = "/";
+
 constexpr unsigned long kTimerSlackForegroundNs = 50000;
 constexpr unsigned long kTimerSlackBackgroundNs = 40000000;
 
@@ -123,22 +125,22 @@
   // hack for now to put some form of permission logic in place while a longer
   // term solution is developed.
   using AllowRootSystem =
-      CheckAnd<SameProcess, CheckOr<UserId<AID_ROOT, AID_SYSTEM>,
-                                    GroupId<AID_SYSTEM>>>;
+      CheckAnd<SameProcess,
+               CheckOr<UserId<AID_ROOT, AID_SYSTEM>, GroupId<AID_SYSTEM>>>;
   using AllowRootSystemGraphics =
       CheckAnd<SameProcess, CheckOr<UserId<AID_ROOT, AID_SYSTEM, AID_GRAPHICS>,
                                     GroupId<AID_SYSTEM, AID_GRAPHICS>>>;
   using AllowRootSystemAudio =
       CheckAnd<SameProcess, CheckOr<UserId<AID_ROOT, AID_SYSTEM, AID_AUDIO>,
                                     GroupId<AID_SYSTEM, AID_AUDIO>>>;
-  using AllowRootSystemTrusted = CheckOr<Trusted, UserId<AID_ROOT, AID_SYSTEM>,
-                                        GroupId<AID_SYSTEM>>;
+  using AllowRootSystemTrusted =
+      CheckOr<Trusted, UserId<AID_ROOT, AID_SYSTEM>, GroupId<AID_SYSTEM>>;
 
   partition_permission_check_ = AllowRootSystemTrusted::Check;
 
   // Setup the scheduler classes.
   // TODO(eieio): Replace this with a device-specific config file.
-  scheduler_classes_ = {
+  scheduler_policies_ = {
       {"audio:low",
        {.timer_slack = kTimerSlackForegroundNs,
         .scheduler_policy = SCHED_FIFO | SCHED_RESET_ON_FORK,
@@ -183,12 +185,14 @@
        {.timer_slack = kTimerSlackForegroundNs,
         .scheduler_policy = SCHED_FIFO | SCHED_RESET_ON_FORK,
         .priority = fifo_medium + 2,
-        .permission_check = AllowRootSystemTrusted::Check}},
+        .permission_check = AllowRootSystemTrusted::Check,
+        "/system/performance"}},
       {"vr:app:render",
        {.timer_slack = kTimerSlackForegroundNs,
         .scheduler_policy = SCHED_FIFO | SCHED_RESET_ON_FORK,
         .priority = fifo_medium + 1,
-        .permission_check = AllowRootSystemTrusted::Check}},
+        .permission_check = AllowRootSystemTrusted::Check,
+        "/application/performance"}},
       {"normal",
        {.timer_slack = kTimerSlackForegroundNs,
         .scheduler_policy = SCHED_NORMAL,
@@ -219,14 +223,80 @@
 
 Status<void> PerformanceService::OnSetSchedulerPolicy(
     Message& message, pid_t task_id, const std::string& scheduler_policy) {
-  // Forward to scheduler class handler for now. In the future this method will
-  // subsume the others by unifying both scheduler class and cpu partiton into a
-  // single policy concept.
   ALOGI(
       "PerformanceService::OnSetSchedulerPolicy: task_id=%d "
       "scheduler_policy=%s",
       task_id, scheduler_policy.c_str());
-  return OnSetSchedulerClass(message, task_id, scheduler_policy);
+
+  Task task(task_id);
+  if (!task) {
+    ALOGE(
+        "PerformanceService::OnSetSchedulerPolicy: Unable to access /proc/%d "
+        "to gather task information.",
+        task_id);
+    return ErrorStatus(EINVAL);
+  }
+
+  auto search = scheduler_policies_.find(scheduler_policy);
+  if (search != scheduler_policies_.end()) {
+    auto config = search->second;
+
+    // Make sure the sending process is allowed to make the requested change to
+    // this task.
+    if (!config.IsAllowed(message, task))
+      return ErrorStatus(EINVAL);
+
+    // Get the thread group's cpu set. Policies that do not specify a cpuset
+    // should default to this cpuset.
+    std::string thread_group_cpuset;
+    Task thread_group{task.thread_group_id()};
+    if (thread_group) {
+      thread_group_cpuset = thread_group.GetCpuSetPath();
+    } else {
+      ALOGE(
+          "PerformanceService::OnSetSchedulerPolicy: Failed to get thread "
+          "group tgid=%d for task_id=%d",
+          task.thread_group_id(), task_id);
+      thread_group_cpuset = kRootCpuSet;
+    }
+
+    std::string target_cpuset;
+    if (config.cpuset.empty()) {
+      target_cpuset = thread_group_cpuset;
+    } else {
+      target_cpuset = config.cpuset;
+    }
+    ALOGI("PerformanceService::OnSetSchedulerPolicy: Using cpuset=%s",
+          target_cpuset.c_str());
+
+    auto target_set = cpuset_.Lookup(target_cpuset);
+    if (target_set) {
+      auto attach_status = target_set->AttachTask(task_id);
+      ALOGW_IF(!attach_status,
+               "PerformanceService::OnSetSchedulerPolicy: Failed to attach "
+               "task=%d to cpuset=%s: %s",
+               task_id, target_cpuset.c_str(),
+               attach_status.GetErrorMessage().c_str());
+    } else {
+      ALOGW(
+          "PerformanceService::OnSetSchedulerPolicy: Failed to lookup "
+          "cpuset=%s",
+          target_cpuset.c_str());
+    }
+
+    struct sched_param param;
+    param.sched_priority = config.priority;
+
+    sched_setscheduler(task_id, config.scheduler_policy, &param);
+    prctl(PR_SET_TIMERSLACK_PID, config.timer_slack, task_id);
+    return {};
+  } else {
+    ALOGE(
+        "PerformanceService::OnSetSchedulerPolicy: Invalid scheduler_policy=%s "
+        "requested by task=%d.",
+        scheduler_policy.c_str(), task_id);
+    return ErrorStatus(EINVAL);
+  }
 }
 
 Status<void> PerformanceService::OnSetCpuPartition(
@@ -259,8 +329,8 @@
   if (!task)
     return ErrorStatus(EINVAL);
 
-  auto search = scheduler_classes_.find(scheduler_class);
-  if (search != scheduler_classes_.end()) {
+  auto search = scheduler_policies_.find(scheduler_class);
+  if (search != scheduler_policies_.end()) {
     auto config = search->second;
 
     // Make sure the sending process is allowed to make the requested change to
diff --git a/services/vr/performanced/performance_service.h b/services/vr/performanced/performance_service.h
index b28d94a..6b519ab 100644
--- a/services/vr/performanced/performance_service.h
+++ b/services/vr/performanced/performance_service.h
@@ -44,13 +44,13 @@
   int sched_fifo_min_priority_;
   int sched_fifo_max_priority_;
 
-  // Scheduler class config type.
-  struct SchedulerClassConfig {
+  struct SchedulerPolicyConfig {
     unsigned long timer_slack;
     int scheduler_policy;
     int priority;
     std::function<bool(const pdx::Message& message, const Task& task)>
         permission_check;
+    std::string cpuset;
 
     // Check the permisison of the given task to use this scheduler class. If a
     // permission check function is not set then operations are only allowed on
@@ -65,7 +65,7 @@
     }
   };
 
-  std::unordered_map<std::string, SchedulerClassConfig> scheduler_classes_;
+  std::unordered_map<std::string, SchedulerPolicyConfig> scheduler_policies_;
 
   std::function<bool(const pdx::Message& message, const Task& task)>
       partition_permission_check_;
diff --git a/services/vr/performanced/performance_service_tests.cpp b/services/vr/performanced/performance_service_tests.cpp
index 274a1b3..4065785 100644
--- a/services/vr/performanced/performance_service_tests.cpp
+++ b/services/vr/performanced/performance_service_tests.cpp
@@ -1,24 +1,65 @@
 #include <errno.h>
 #include <sched.h>
+#include <stdio.h>
 #include <sys/types.h>
 #include <unistd.h>
 
 #include <condition_variable>
 #include <cstdlib>
+#include <iostream>
 #include <mutex>
+#include <sstream>
 #include <thread>
+#include <utility>
 
+#include <android-base/unique_fd.h>
 #include <dvr/performance_client_api.h>
 #include <gtest/gtest.h>
 #include <private/android_filesystem_config.h>
 
+#include "stdio_filebuf.h"
+#include "string_trim.h"
+#include "unique_file.h"
+
+using android::dvr::Trim;
+using android::dvr::UniqueFile;
+using android::dvr::stdio_filebuf;
+
 namespace {
 
 const char kTrustedUidEnvironmentVariable[] = "GTEST_TRUSTED_UID";
 
+const char kProcBase[] = "/proc";
+
+std::pair<UniqueFile, int> OpenTaskFile(pid_t task_id,
+                                        const std::string& name) {
+  std::ostringstream stream;
+  stream << kProcBase << "/" << task_id << "/" << name;
+
+  UniqueFile file{fopen(stream.str().c_str(), "r")};
+  const int error = file ? 0 : errno;
+  return {std::move(file), error};
+}
+
+std::string GetTaskCpuSet(pid_t task_id) {
+  int error;
+  UniqueFile file;
+
+  std::tie(file, error) = OpenTaskFile(task_id, "cpuset");
+  if (!file)
+    return std::string("errno:") + strerror(error);
+
+  stdio_filebuf<char> filebuf(file.get());
+  std::istream file_stream(&filebuf);
+
+  std::string line;
+  std::getline(file_stream, line);
+  return Trim(line);
+}
+
 }  // anonymous namespace
 
-TEST(DISABLED_PerformanceTest, SetCpuPartition) {
+TEST(PerformanceTest, SetCpuPartition) {
   int error;
 
   // Test setting the the partition for the current task.
@@ -59,13 +100,6 @@
   }
   thread.join();
 
-  // Test setting the partition for a task that isn't valid using
-  // the task id of the thread that we just joined. Technically the
-  // id could wrap around by the time we get here, but this is
-  // extremely unlikely.
-  error = dvrSetCpuPartition(task_id, "/application");
-  EXPECT_EQ(-EINVAL, error);
-
   // Test setting the partition for a task that doesn't belong to us.
   error = dvrSetCpuPartition(1, "/application");
   EXPECT_EQ(-EINVAL, error);
@@ -73,6 +107,10 @@
   // Test setting the partition to one that doesn't exist.
   error = dvrSetCpuPartition(0, "/foobar");
   EXPECT_EQ(-ENOENT, error);
+
+  // Set the test back to the root partition.
+  error = dvrSetCpuPartition(0, "/");
+  EXPECT_EQ(0, error);
 }
 
 TEST(PerformanceTest, SetSchedulerClass) {
@@ -96,8 +134,6 @@
   EXPECT_EQ(-EINVAL, error);
 }
 
-// This API mirrors SetSchedulerClass for now. Replace with with a more specific
-// test once the policy API is fully implemented.
 TEST(PerformanceTest, SetSchedulerPolicy) {
   int error;
 
@@ -115,6 +151,50 @@
 
   error = dvrSetSchedulerPolicy(0, "foobar");
   EXPECT_EQ(-EINVAL, error);
+
+  // Set the test back to the root partition.
+  error = dvrSetCpuPartition(0, "/");
+  EXPECT_EQ(0, error);
+
+  const std::string original_cpuset = GetTaskCpuSet(gettid());
+  EXPECT_EQ("/", original_cpuset);
+
+  error = dvrSetSchedulerPolicy(0, "vr:system:arp");
+  EXPECT_EQ(0, error);
+  EXPECT_EQ(SCHED_FIFO | SCHED_RESET_ON_FORK, sched_getscheduler(0));
+
+  const std::string new_cpuset = GetTaskCpuSet(gettid());
+  EXPECT_NE(original_cpuset, new_cpuset);
+
+  // The cpuset for the thread group is now new_cpuset. Scheduler profiles that
+  // do not specify a cpuset should not change the cpuset of a thread, except to
+  // restore it to the thread group cpuset.
+  std::string thread_original_cpuset;
+  std::string thread_new_cpuset;
+  std::string thread_final_cpuset;
+
+  std::thread thread{
+      [&thread_original_cpuset, &thread_new_cpuset, &thread_final_cpuset]() {
+        thread_original_cpuset = GetTaskCpuSet(gettid());
+
+        int error = dvrSetSchedulerPolicy(0, "vr:app:render");
+        EXPECT_EQ(0, error);
+
+        thread_new_cpuset = GetTaskCpuSet(gettid());
+
+        error = dvrSetSchedulerPolicy(0, "normal");
+        EXPECT_EQ(0, error);
+
+        thread_final_cpuset = GetTaskCpuSet(gettid());
+      }};
+  thread.join();
+
+  EXPECT_EQ(new_cpuset, thread_original_cpuset);
+  EXPECT_NE(new_cpuset, thread_new_cpuset);
+  EXPECT_EQ(new_cpuset, thread_final_cpuset);
+
+  error = dvrSetCpuPartition(0, original_cpuset.c_str());
+  EXPECT_EQ(0, error);
 }
 
 TEST(PerformanceTest, SchedulerClassResetOnFork) {
@@ -424,11 +504,11 @@
     error = dvrSetSchedulerPolicy(0, "audio:high");
     EXPECT_EQ(-EINVAL, error);
     error = dvrSetSchedulerPolicy(0, "graphics");
-    EXPECT_EQ(0, error);
+    EXPECT_EQ(-EINVAL, error);
     error = dvrSetSchedulerPolicy(0, "graphics:low");
-    EXPECT_EQ(0, error);
+    EXPECT_EQ(-EINVAL, error);
     error = dvrSetSchedulerPolicy(0, "graphics:high");
-    EXPECT_EQ(0, error);
+    EXPECT_EQ(-EINVAL, error);
     error = dvrSetSchedulerPolicy(0, "sensors");
     EXPECT_EQ(-EINVAL, error);
     error = dvrSetSchedulerPolicy(0, "sensors:low");
diff --git a/services/vr/performanced/task.cpp b/services/vr/performanced/task.cpp
index 1175a7b..c2f078e 100644
--- a/services/vr/performanced/task.cpp
+++ b/services/vr/performanced/task.cpp
@@ -48,15 +48,18 @@
       thread_count_(0),
       cpus_allowed_mask_(0) {
   task_fd_ = OpenTaskDirectory(task_id_);
-  ALOGE_IF(task_fd_.get() < 0,
+  const int error = errno;
+  ALOGE_IF(task_fd_.get() < 0 && error != EACCES,
            "Task::Task: Failed to open task directory for task_id=%d: %s",
-           task_id, strerror(errno));
+           task_id, strerror(error));
 
-  ReadStatusFields();
-
-  ALOGD_IF(TRACE, "Task::Task: task_id=%d name=%s tgid=%d ppid=%d cpu_mask=%x",
-           task_id_, name_.c_str(), thread_group_id_, parent_process_id_,
-           cpus_allowed_mask_);
+  if (IsValid()) {
+    ReadStatusFields();
+    ALOGD_IF(TRACE,
+             "Task::Task: task_id=%d name=%s tgid=%d ppid=%d cpu_mask=%x",
+             task_id_, name_.c_str(), thread_group_id_, parent_process_id_,
+             cpus_allowed_mask_);
+  }
 }
 
 base::unique_fd Task::OpenTaskFile(const std::string& name) const {