Merge "logd: always report the UID of a log message"
diff --git a/fs_mgr/libsnapshot/test_helpers.cpp b/fs_mgr/libsnapshot/test_helpers.cpp
index 1a6a593..539c5c5 100644
--- a/fs_mgr/libsnapshot/test_helpers.cpp
+++ b/fs_mgr/libsnapshot/test_helpers.cpp
@@ -92,21 +92,14 @@
 }
 
 std::optional<std::string> GetHash(const std::string& path) {
-    unique_fd fd(open(path.c_str(), O_RDONLY));
-    char buf[4096];
+    std::string content;
+    if (!android::base::ReadFileToString(path, &content, true)) {
+        PLOG(ERROR) << "Cannot access " << path;
+        return std::nullopt;
+    }
     SHA256_CTX ctx;
     SHA256_Init(&ctx);
-    while (true) {
-        ssize_t n = TEMP_FAILURE_RETRY(read(fd.get(), buf, sizeof(buf)));
-        if (n < 0) {
-            PLOG(ERROR) << "Cannot read " << path;
-            return std::nullopt;
-        }
-        if (n == 0) {
-            break;
-        }
-        SHA256_Update(&ctx, buf, n);
-    }
+    SHA256_Update(&ctx, content.c_str(), content.size());
     uint8_t out[32];
     SHA256_Final(out, &ctx);
     return ToHexString(out, sizeof(out));
diff --git a/libcutils/sched_policy_test.cpp b/libcutils/sched_policy_test.cpp
index a321c90..b9e2832 100644
--- a/libcutils/sched_policy_test.cpp
+++ b/libcutils/sched_policy_test.cpp
@@ -107,6 +107,18 @@
 
 TEST(SchedPolicy, get_sched_policy_name) {
     EXPECT_STREQ("bg", get_sched_policy_name(SP_BACKGROUND));
-    EXPECT_STREQ("error", get_sched_policy_name(SchedPolicy(-2)));
-    EXPECT_STREQ("error", get_sched_policy_name(SP_CNT));
+    EXPECT_EQ(nullptr, get_sched_policy_name(SchedPolicy(-2)));
+    EXPECT_EQ(nullptr, get_sched_policy_name(SP_CNT));
+}
+
+TEST(SchedPolicy, get_cpuset_policy_profile_name) {
+    EXPECT_STREQ("CPUSET_SP_BACKGROUND", get_cpuset_policy_profile_name(SP_BACKGROUND));
+    EXPECT_EQ(nullptr, get_cpuset_policy_profile_name(SchedPolicy(-2)));
+    EXPECT_EQ(nullptr, get_cpuset_policy_profile_name(SP_CNT));
+}
+
+TEST(SchedPolicy, get_sched_policy_profile_name) {
+    EXPECT_STREQ("SCHED_SP_BACKGROUND", get_sched_policy_profile_name(SP_BACKGROUND));
+    EXPECT_EQ(nullptr, get_sched_policy_profile_name(SchedPolicy(-2)));
+    EXPECT_EQ(nullptr, get_sched_policy_profile_name(SP_CNT));
 }
diff --git a/liblog/include/log/event_tag_map.h b/liblog/include/log/event_tag_map.h
index 2687b3a..f7ec208 100644
--- a/liblog/include/log/event_tag_map.h
+++ b/liblog/include/log/event_tag_map.h
@@ -16,6 +16,8 @@
 
 #pragma once
 
+#include <stddef.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/liblog/include/log/log.h b/liblog/include/log/log.h
index 5928649..90d1e76 100644
--- a/liblog/include/log/log.h
+++ b/liblog/include/log/log.h
@@ -22,7 +22,6 @@
 #endif
 #include <stdint.h> /* uint16_t, int32_t */
 #include <stdio.h>
-#include <sys/types.h>
 #include <time.h>
 #include <unistd.h>
 
@@ -65,21 +64,6 @@
 #endif
 #endif
 
-/* --------------------------------------------------------------------- */
-
-/*
- * This file uses ", ## __VA_ARGS__" zero-argument token pasting to
- * work around issues with debug-only syntax errors in assertions
- * that are missing format strings.  See commit
- * 19299904343daf191267564fe32e6cd5c165cd42
- */
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wgnu-zero-variadic-macro-arguments"
-#endif
-
-/* --------------------------------------------------------------------- */
-
 /*
  * Event logging.
  */
@@ -164,10 +148,6 @@
  */
 void __android_log_close(void);
 
-#if defined(__clang__)
-#pragma clang diagnostic pop
-#endif
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/liblog/include/log/log_event_list.h b/liblog/include/log/log_event_list.h
index 636d417..deadf20 100644
--- a/liblog/include/log/log_event_list.h
+++ b/liblog/include/log/log_event_list.h
@@ -36,16 +36,11 @@
 /*
  * The opaque context used to manipulate lists of events.
  */
-#ifndef __android_log_context_defined
-#define __android_log_context_defined
 typedef struct android_log_context_internal* android_log_context;
-#endif
 
 /*
  * Elements returned when reading a list of events.
  */
-#ifndef __android_log_list_element_defined
-#define __android_log_list_element_defined
 typedef struct {
   AndroidEventLogType type;
   uint16_t complete;
@@ -57,7 +52,6 @@
     float float32;
   } data;
 } android_log_list_element;
-#endif
 
 /*
  * Creates a context associated with an event tag to write elements to
@@ -104,8 +98,6 @@
 int android_log_destroy(android_log_context* ctx);
 
 #ifdef __cplusplus
-#ifndef __class_android_log_event_list_defined
-#define __class_android_log_event_list_defined
 /* android_log_list C++ helpers */
 extern "C++" {
 class android_log_event_list {
@@ -280,7 +272,6 @@
 };
 }
 #endif
-#endif
 
 #ifdef __cplusplus
 }
diff --git a/liblog/include/log/log_read.h b/liblog/include/log/log_read.h
index fdef306..2079e7a 100644
--- a/liblog/include/log/log_read.h
+++ b/liblog/include/log/log_read.h
@@ -53,8 +53,6 @@
 /*
  * The userspace structure for version 1 of the logger_entry ABI.
  */
-#ifndef __struct_logger_entry_defined
-#define __struct_logger_entry_defined
 struct logger_entry {
   uint16_t len;   /* length of the payload */
   uint16_t __pad; /* no matter what, we get 2 bytes of padding */
@@ -64,13 +62,10 @@
   int32_t nsec;   /* nanoseconds */
   char msg[0]; /* the entry's payload */
 };
-#endif
 
 /*
  * The userspace structure for version 2 of the logger_entry ABI.
  */
-#ifndef __struct_logger_entry_v2_defined
-#define __struct_logger_entry_v2_defined
 struct logger_entry_v2 {
   uint16_t len;      /* length of the payload */
   uint16_t hdr_size; /* sizeof(struct logger_entry_v2) */
@@ -81,13 +76,10 @@
   uint32_t euid;     /* effective UID of logger */
   char msg[0]; /* the entry's payload */
 } __attribute__((__packed__));
-#endif
 
 /*
  * The userspace structure for version 3 of the logger_entry ABI.
  */
-#ifndef __struct_logger_entry_v3_defined
-#define __struct_logger_entry_v3_defined
 struct logger_entry_v3 {
   uint16_t len;      /* length of the payload */
   uint16_t hdr_size; /* sizeof(struct logger_entry_v3) */
@@ -98,13 +90,10 @@
   uint32_t lid;      /* log id of the payload */
   char msg[0]; /* the entry's payload */
 } __attribute__((__packed__));
-#endif
 
 /*
  * The userspace structure for version 4 of the logger_entry ABI.
  */
-#ifndef __struct_logger_entry_v4_defined
-#define __struct_logger_entry_v4_defined
 struct logger_entry_v4 {
   uint16_t len;      /* length of the payload */
   uint16_t hdr_size; /* sizeof(struct logger_entry_v4) */
@@ -116,7 +105,6 @@
   uint32_t uid;      /* generating process's uid */
   char msg[0]; /* the entry's payload */
 };
-#endif
 #pragma clang diagnostic pop
 
 /*
@@ -133,8 +121,6 @@
  */
 #define LOGGER_ENTRY_MAX_LEN (5 * 1024)
 
-#ifndef __struct_log_msg_defined
-#define __struct_log_msg_defined
 struct log_msg {
   union {
     unsigned char buf[LOGGER_ENTRY_MAX_LEN + 1];
@@ -191,7 +177,6 @@
   }
 #endif
 };
-#endif
 
 struct logger;
 
diff --git a/liblog/include/log/log_time.h b/liblog/include/log/log_time.h
index 1b33331..6b4458c 100644
--- a/liblog/include/log/log_time.h
+++ b/liblog/include/log/log_time.h
@@ -24,9 +24,6 @@
 #define US_PER_SEC 1000000ULL
 #define MS_PER_SEC 1000ULL
 
-#ifndef __struct_log_time_defined
-#define __struct_log_time_defined
-
 #define LOG_TIME_SEC(t) ((t)->tv_sec)
 /* next power of two after NS_PER_SEC */
 #define LOG_TIME_NSEC(t) ((t)->tv_nsec & (UINT32_MAX >> 2))
@@ -164,5 +161,3 @@
 } __attribute__((__packed__)) log_time;
 
 #endif /* __cplusplus */
-
-#endif /* __struct_log_time_defined */
diff --git a/liblog/include/log/logprint.h b/liblog/include/log/logprint.h
index 8f4b187..7dfd914 100644
--- a/liblog/include/log/logprint.h
+++ b/liblog/include/log/logprint.h
@@ -16,7 +16,8 @@
 
 #pragma once
 
-#include <pthread.h>
+#include <stdint.h>
+#include <sys/types.h>
 
 #include <android/log.h>
 #include <log/event_tag_map.h>
diff --git a/liblog/pmsg_reader.cpp b/liblog/pmsg_reader.cpp
index 9c5bc95..ce923f3 100644
--- a/liblog/pmsg_reader.cpp
+++ b/liblog/pmsg_reader.cpp
@@ -62,58 +62,9 @@
   return -EBADF;
 }
 
-/* Determine the credentials of the caller */
-static bool uid_has_log_permission(uid_t uid) {
-  return (uid == AID_SYSTEM) || (uid == AID_LOG) || (uid == AID_ROOT) || (uid == AID_LOGD);
-}
-
-static uid_t get_best_effective_uid() {
-  uid_t euid;
-  uid_t uid;
-  gid_t gid;
-  ssize_t i;
-  static uid_t last_uid = (uid_t)-1;
-
-  if (last_uid != (uid_t)-1) {
-    return last_uid;
-  }
-  uid = __android_log_uid();
-  if (uid_has_log_permission(uid)) {
-    return last_uid = uid;
-  }
-  euid = geteuid();
-  if (uid_has_log_permission(euid)) {
-    return last_uid = euid;
-  }
-  gid = getgid();
-  if (uid_has_log_permission(gid)) {
-    return last_uid = gid;
-  }
-  gid = getegid();
-  if (uid_has_log_permission(gid)) {
-    return last_uid = gid;
-  }
-  i = getgroups((size_t)0, NULL);
-  if (i > 0) {
-    gid_t list[i];
-
-    getgroups(i, list);
-    while (--i >= 0) {
-      if (uid_has_log_permission(list[i])) {
-        return last_uid = list[i];
-      }
-    }
-  }
-  return last_uid = uid;
-}
-
 static int pmsgClear(struct android_log_logger* logger __unused,
                      struct android_log_transport_context* transp __unused) {
-  if (uid_has_log_permission(get_best_effective_uid())) {
-    return unlink("/sys/fs/pstore/pmsg-ramoops-0");
-  }
-  errno = EPERM;
-  return -1;
+  return unlink("/sys/fs/pstore/pmsg-ramoops-0");
 }
 
 /*
@@ -128,14 +79,12 @@
                     struct android_log_transport_context* transp, struct log_msg* log_msg) {
   ssize_t ret;
   off_t current, next;
-  uid_t uid;
   struct __attribute__((__packed__)) {
     android_pmsg_log_header_t p;
     android_log_header_t l;
     uint8_t prio;
   } buf;
   static uint8_t preread_count;
-  bool is_system;
 
   memset(log_msg, 0, sizeof(*log_msg));
 
@@ -195,37 +144,30 @@
           ((logger_list->start.tv_sec != buf.l.realtime.tv_sec) ||
            (logger_list->start.tv_nsec <= buf.l.realtime.tv_nsec)))) &&
         (!logger_list->pid || (logger_list->pid == buf.p.pid))) {
-      uid = get_best_effective_uid();
-      is_system = uid_has_log_permission(uid);
-      if (is_system || (uid == buf.p.uid)) {
-        char* msg = is_system ? log_msg->entry_v4.msg : log_msg->entry_v3.msg;
-        *msg = buf.prio;
-        fd = atomic_load(&transp->context.fd);
-        if (fd <= 0) {
-          return -EBADF;
-        }
-        ret = TEMP_FAILURE_RETRY(read(fd, msg + sizeof(buf.prio), buf.p.len - sizeof(buf)));
-        if (ret < 0) {
-          return -errno;
-        }
-        if (ret != (ssize_t)(buf.p.len - sizeof(buf))) {
-          return -EIO;
-        }
-
-        log_msg->entry_v4.len = buf.p.len - sizeof(buf) + sizeof(buf.prio);
-        log_msg->entry_v4.hdr_size =
-            is_system ? sizeof(log_msg->entry_v4) : sizeof(log_msg->entry_v3);
-        log_msg->entry_v4.pid = buf.p.pid;
-        log_msg->entry_v4.tid = buf.l.tid;
-        log_msg->entry_v4.sec = buf.l.realtime.tv_sec;
-        log_msg->entry_v4.nsec = buf.l.realtime.tv_nsec;
-        log_msg->entry_v4.lid = buf.l.id;
-        if (is_system) {
-          log_msg->entry_v4.uid = buf.p.uid;
-        }
-
-        return ret + sizeof(buf.prio) + log_msg->entry_v4.hdr_size;
+      char* msg = log_msg->entry_v4.msg;
+      *msg = buf.prio;
+      fd = atomic_load(&transp->context.fd);
+      if (fd <= 0) {
+        return -EBADF;
       }
+      ret = TEMP_FAILURE_RETRY(read(fd, msg + sizeof(buf.prio), buf.p.len - sizeof(buf)));
+      if (ret < 0) {
+        return -errno;
+      }
+      if (ret != (ssize_t)(buf.p.len - sizeof(buf))) {
+        return -EIO;
+      }
+
+      log_msg->entry_v4.len = buf.p.len - sizeof(buf) + sizeof(buf.prio);
+      log_msg->entry_v4.hdr_size = sizeof(log_msg->entry_v4);
+      log_msg->entry_v4.pid = buf.p.pid;
+      log_msg->entry_v4.tid = buf.l.tid;
+      log_msg->entry_v4.sec = buf.l.realtime.tv_sec;
+      log_msg->entry_v4.nsec = buf.l.realtime.tv_nsec;
+      log_msg->entry_v4.lid = buf.l.id;
+      log_msg->entry_v4.uid = buf.p.uid;
+
+      return ret + sizeof(buf.prio) + log_msg->entry_v4.hdr_size;
     }
 
     fd = atomic_load(&transp->context.fd);
@@ -273,13 +215,7 @@
   struct android_log_transport_context transp;
   struct content {
     struct listnode node;
-    union {
-      struct logger_entry_v4 entry;
-      struct logger_entry_v4 entry_v4;
-      struct logger_entry_v3 entry_v3;
-      struct logger_entry_v2 entry_v2;
-      struct logger_entry entry_v1;
-    };
+    struct logger_entry_v4 entry;
   } * content;
   struct names {
     struct listnode node;
diff --git a/liblog/tests/liblog_benchmark.cpp b/liblog/tests/liblog_benchmark.cpp
index 4642b9b..56892a2 100644
--- a/liblog/tests/liblog_benchmark.cpp
+++ b/liblog/tests/liblog_benchmark.cpp
@@ -17,6 +17,7 @@
 #include <fcntl.h>
 #include <inttypes.h>
 #include <poll.h>
+#include <sched.h>
 #include <sys/socket.h>
 #include <sys/syscall.h>
 #include <sys/types.h>
diff --git a/liblog/tests/liblog_test.cpp b/liblog/tests/liblog_test.cpp
index 063c132..94c4fbb 100644
--- a/liblog/tests/liblog_test.cpp
+++ b/liblog/tests/liblog_test.cpp
@@ -62,6 +62,12 @@
     _rc;                                                                 \
   })
 
+// std::unique_ptr doesn't let you provide a pointer to a deleter (android_logger_list_close()) if
+// the type (struct logger_list) is an incomplete type, so we create ListCloser instead.
+struct ListCloser {
+  void operator()(struct logger_list* list) { android_logger_list_close(list); }
+};
+
 // This function is meant to be used for most log tests, it does the following:
 // 1) Open the log_buffer with a blocking reader
 // 2) Write the messages via write_messages
@@ -75,11 +81,6 @@
 static void RunLogTests(log_id_t log_buffer, FWrite write_messages, FCheck check_message) {
   pid_t pid = getpid();
 
-  // std::unique_ptr doesn't let you provide a pointer to a deleter (android_logger_list_close()) if
-  // the type (struct logger_list) is an incomplete type, so we create ListCloser instead.
-  struct ListCloser {
-    void operator()(struct logger_list* list) { android_logger_list_close(list); }
-  };
   auto logger_list = std::unique_ptr<struct logger_list, ListCloser>{
       android_logger_list_open(log_buffer, ANDROID_LOG_RDONLY, 1000, pid)};
   ASSERT_TRUE(logger_list);
@@ -946,7 +947,6 @@
 when you depart from me, sorrow abides and happiness\n\
 takes his leave.";
 
-#ifdef ENABLE_FLAKY_TESTS
 TEST(liblog, max_payload) {
 #ifdef __ANDROID__
   static const char max_payload_tag[] = "TEST_max_payload_and_longish_tag_XXXX";
@@ -995,7 +995,6 @@
   GTEST_LOG_(INFO) << "This test does nothing.\n";
 #endif
 }
-#endif  // ENABLE_FLAKY_TESTS
 
 TEST(liblog, __android_log_buf_print__maxtag) {
 #ifdef __ANDROID__
@@ -1089,11 +1088,20 @@
 #endif
 }
 
-#ifdef ENABLE_FLAKY_TESTS
 TEST(liblog, dual_reader) {
 #ifdef __ANDROID__
+  static const int expected_count1 = 25;
+  static const int expected_count2 = 25;
 
-  static const int num = 25;
+  pid_t pid = getpid();
+
+  auto logger_list1 = std::unique_ptr<struct logger_list, ListCloser>{
+      android_logger_list_open(LOG_ID_MAIN, ANDROID_LOG_RDONLY, expected_count1, pid)};
+  ASSERT_TRUE(logger_list1);
+
+  auto logger_list2 = std::unique_ptr<struct logger_list, ListCloser>{
+      android_logger_list_open(LOG_ID_MAIN, ANDROID_LOG_RDONLY, expected_count2, pid)};
+  ASSERT_TRUE(logger_list2);
 
   for (int i = 25; i > 0; --i) {
     static const char fmt[] = "dual_reader %02d";
@@ -1102,32 +1110,46 @@
     LOG_FAILURE_RETRY(__android_log_buf_write(LOG_ID_MAIN, ANDROID_LOG_INFO,
                                               "liblog", buffer));
   }
-  usleep(1000000);
 
-  struct logger_list* logger_list1;
-  ASSERT_TRUE(NULL != (logger_list1 = android_logger_list_open(
-                           LOG_ID_MAIN,
-                           ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK, num, 0)));
+  alarm(2);
+  auto alarm_guard = android::base::make_scope_guard([] { alarm(0); });
 
-  struct logger_list* logger_list2;
+  // Wait until we see all messages with the blocking reader.
+  int count1 = 0;
+  int count2 = 0;
 
-  if (NULL == (logger_list2 = android_logger_list_open(
-                   LOG_ID_MAIN, ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK,
-                   num - 10, 0))) {
-    android_logger_list_close(logger_list1);
-    ASSERT_TRUE(NULL != logger_list2);
+  while (count1 != expected_count2 || count2 != expected_count2) {
+    log_msg log_msg;
+    if (count1 < expected_count1) {
+      ASSERT_GT(android_logger_list_read(logger_list1.get(), &log_msg), 0);
+      count1++;
+    }
+    if (count2 < expected_count2) {
+      ASSERT_GT(android_logger_list_read(logger_list2.get(), &log_msg), 0);
+      count2++;
+    }
   }
 
-  int count1 = 0;
+  // Test again with the nonblocking reader.
+  auto logger_list_non_block1 =
+      std::unique_ptr<struct logger_list, ListCloser>{android_logger_list_open(
+          LOG_ID_MAIN, ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK, expected_count1, pid)};
+  ASSERT_TRUE(logger_list_non_block1);
+
+  auto logger_list_non_block2 =
+      std::unique_ptr<struct logger_list, ListCloser>{android_logger_list_open(
+          LOG_ID_MAIN, ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK, expected_count2, pid)};
+  ASSERT_TRUE(logger_list_non_block2);
+  count1 = 0;
+  count2 = 0;
   bool done1 = false;
-  int count2 = 0;
   bool done2 = false;
 
-  do {
+  while (!done1 || !done2) {
     log_msg log_msg;
 
     if (!done1) {
-      if (android_logger_list_read(logger_list1, &log_msg) <= 0) {
+      if (android_logger_list_read(logger_list_non_block1.get(), &log_msg) <= 0) {
         done1 = true;
       } else {
         ++count1;
@@ -1135,26 +1157,21 @@
     }
 
     if (!done2) {
-      if (android_logger_list_read(logger_list2, &log_msg) <= 0) {
+      if (android_logger_list_read(logger_list_non_block2.get(), &log_msg) <= 0) {
         done2 = true;
       } else {
         ++count2;
       }
     }
-  } while ((!done1) || (!done2));
+  }
 
-  android_logger_list_close(logger_list1);
-  android_logger_list_close(logger_list2);
-
-  EXPECT_EQ(num, count1);
-  EXPECT_EQ(num - 10, count2);
+  EXPECT_EQ(expected_count1, count1);
+  EXPECT_EQ(expected_count2, count2);
 #else
   GTEST_LOG_(INFO) << "This test does nothing.\n";
 #endif
 }
-#endif  // ENABLE_FLAKY_TESTS
 
-#ifdef ENABLE_FLAKY_TESTS
 static bool checkPriForTag(AndroidLogFormat* p_format, const char* tag,
                            android_LogPriority pri) {
   return android_log_shouldPrintLine(p_format, tag, pri) &&
@@ -1230,7 +1247,6 @@
 
   android_log_format_free(p_format);
 }
-#endif  // ENABLE_FLAKY_TESTS
 
 #ifdef ENABLE_FLAKY_TESTS
 TEST(liblog, is_loggable) {
@@ -2609,7 +2625,6 @@
 #endif
 }
 
-#ifdef ENABLE_FLAKY_TESTS
 TEST(liblog, create_android_logger_overflow) {
   android_log_context ctx;
 
@@ -2636,7 +2651,6 @@
   EXPECT_LE(0, android_log_destroy(&ctx));
   ASSERT_TRUE(NULL == ctx);
 }
-#endif  // ENABLE_FLAKY_TESTS
 
 #ifdef ENABLE_FLAKY_TESTS
 #ifdef __ANDROID__
@@ -2777,7 +2791,6 @@
 }
 #endif  // ENABLE_FLAKY_TESTS
 
-#ifdef ENABLE_FLAKY_TESTS
 TEST(liblog, android_lookupEventTagNum) {
 #ifdef __ANDROID__
   EventTagMap* map = android_openEventTagMap(NULL);
@@ -2794,4 +2807,3 @@
   GTEST_LOG_(INFO) << "This test does nothing.\n";
 #endif
 }
-#endif  // ENABLE_FLAKY_TESTS
diff --git a/libprocessgroup/include/processgroup/sched_policy.h b/libprocessgroup/include/processgroup/sched_policy.h
index 3c498da..945d90c 100644
--- a/libprocessgroup/include/processgroup/sched_policy.h
+++ b/libprocessgroup/include/processgroup/sched_policy.h
@@ -70,11 +70,22 @@
 extern int get_sched_policy(int tid, SchedPolicy* policy);
 
 /* Return a displayable string corresponding to policy.
- * Return value: non-NULL NUL-terminated name of unspecified length;
+ * Return value: NUL-terminated name of unspecified length, nullptr if invalid;
  * the caller is responsible for displaying the useful part of the string.
  */
 extern const char* get_sched_policy_name(SchedPolicy policy);
 
+/* Return the aggregated task profile name corresponding to cpuset policy.
+ * Return value: NUL-terminated name of unspecified length, nullptr if invalid;
+ * the caller could use it to call SetTaskProfiles.
+ */
+extern const char* get_cpuset_policy_profile_name(SchedPolicy policy);
+
+/* Return the aggregated task profile name corresponding to sched policy.
+ * Return value: NUL-terminated name of unspecified length, nullptr if invalid;
+ * the caller could use it to call SetTaskProfiles.
+ */
+extern const char* get_sched_policy_profile_name(SchedPolicy policy);
 #ifdef __cplusplus
 }
 #endif
diff --git a/libprocessgroup/sched_policy.cpp b/libprocessgroup/sched_policy.cpp
index 6b0ab87..16339d3 100644
--- a/libprocessgroup/sched_policy.cpp
+++ b/libprocessgroup/sched_policy.cpp
@@ -212,7 +212,45 @@
     };
     static_assert(arraysize(kSchedPolicyNames) == SP_CNT, "missing name");
     if (policy < SP_BACKGROUND || policy >= SP_CNT) {
-        return "error";
+        return nullptr;
     }
     return kSchedPolicyNames[policy];
 }
+
+const char* get_cpuset_policy_profile_name(SchedPolicy policy) {
+    /*
+     *  cpuset profile array for:
+     *  SP_DEFAULT(-1), SP_BACKGROUND(0), SP_FOREGROUND(1),
+     *  SP_SYSTEM(2), SP_AUDIO_APP(3), SP_AUDIO_SYS(4),
+     *  SP_TOP_APP(5), SP_RT_APP(6), SP_RESTRICTED(7)
+     *  index is policy + 1
+     *  this need keep in sync with SchedPolicy enum
+     */
+    static constexpr const char* kCpusetProfiles[SP_CNT + 1] = {
+            "CPUSET_SP_DEFAULT", "CPUSET_SP_BACKGROUND", "CPUSET_SP_FOREGROUND",
+            "CPUSET_SP_SYSTEM",  "CPUSET_SP_FOREGROUND", "CPUSET_SP_FOREGROUND",
+            "CPUSET_SP_TOP_APP", "CPUSET_SP_DEFAULT",    "CPUSET_SP_RESTRICTED"};
+    if (policy < SP_DEFAULT || policy >= SP_CNT) {
+        return nullptr;
+    }
+    return kCpusetProfiles[policy + 1];
+}
+
+const char* get_sched_policy_profile_name(SchedPolicy policy) {
+    /*
+     *  sched profile array for:
+     *  SP_DEFAULT(-1), SP_BACKGROUND(0), SP_FOREGROUND(1),
+     *  SP_SYSTEM(2), SP_AUDIO_APP(3), SP_AUDIO_SYS(4),
+     *  SP_TOP_APP(5), SP_RT_APP(6), SP_RESTRICTED(7)
+     *  index is policy + 1
+     *  this need keep in sync with SchedPolicy enum
+     */
+    static constexpr const char* kSchedProfiles[SP_CNT + 1] = {
+            "SCHED_SP_DEFAULT", "SCHED_SP_BACKGROUND", "SCHED_SP_FOREGROUND",
+            "SCHED_SP_DEFAULT", "SCHED_SP_FOREGROUND", "SCHED_SP_FOREGROUND",
+            "SCHED_SP_TOP_APP", "SCHED_SP_RT_APP",     "SCHED_SP_DEFAULT"};
+    if (policy < SP_DEFAULT || policy >= SP_CNT) {
+        return nullptr;
+    }
+    return kSchedProfiles[policy + 1];
+}
diff --git a/libunwindstack/AndroidVersions.md b/libunwindstack/AndroidVersions.md
new file mode 100644
index 0000000..234f639
--- /dev/null
+++ b/libunwindstack/AndroidVersions.md
@@ -0,0 +1,116 @@
+# Unwinder Support Per Android Release
+This document describes the changes in the way the libunwindstack
+unwinder works on different Android versions. It does not describe
+every change in the code made between different versions, but is
+meant to allow an app developer to know what might be supported
+on different versions. It also describes the different way an unwind
+will display on different versions of Android.
+
+## Android P
+libunwindstack was first introduced in Android P.
+
+* Supports up to and including Dwarf 4 unwinding information.
+  See http://dwarfstd.org/ for Dwarf standards.
+* Supports Arm exidx unwinding.
+* Supports the gdb JIT unwinding interface, which is how ART creates unwinding
+  information for the JIT'd Java frames.
+* Supports special frames added to represent an ART Java interpreter frame.
+  ART has marked the dex pc using cfi information that the unwinder
+  understands and handles by adding a new frame in the stacktrace.
+
+## Note
+By default, lld creates two separate maps of the elf in memory, one read-only
+and one read/executable. The libunwindstack on P and the unwinder on older
+versions of Android will not unwind properly in this case. For apps that
+target Android P or older, make sure that `-Wl,--no-rosegment` is
+included in linker arguments when using lld.
+
+## Android Q
+* Fix bug (b/109824792) that handled load bias data incorrectly when
+  FDEs use pc relative addressing in the eh\_frame\_hdr.
+  Unfortunately, this wasn't fixed correctly in Q since it assumes
+  that the bias is coming from the program header for the executable
+  load. The real fix was to use the bias from the actual section data and
+  is not completely fixed until Android R. For apps targeting Android Q,
+  if it is being compiled with the llvm linker lld, it might be necessary
+  to add the linker option `-Wl,-zseparate-code` to avoid creating an elf
+  created this way.
+* Change the way the exidx section offset is found (b/110704153). Before
+  the p\_vaddr value from the program header minus the load bias was used
+  to find the start of the exidx data. Changed to use the p\_offset since
+  it doesn't require any load bias manipulations.
+* Fix bug handling of dwarf sections without any header (b/110235461).
+  Previously, the code assumed that FDEs are non-overlapping, and the FDEs
+  are always in sorted order from low pc to high pc. Thus the code would
+  read the entire set of CIEs/FDEs and then do a binary search to find
+  the appropriate FDE for a given pc. Now the code does a sequential read
+  and stops when it finds the FDE for a pc. It also understands the
+  overlapping FDEs, so find the first FDE that matches a pc. In practice,
+  elf files with this format only ever occurs if the file was generated
+  without an eh\_frame/eh\_frame\_hdr section and only a debug\_frame. The
+  other way this has been observed is when running simpleperf to unwind since
+  sometimes there is not enough information in the eh\_frame for all points
+  in the executable. On Android P, this would result in some incorrect
+  unwinds coming from simpleperf. Nearly all crashes from Android P should
+  be correct since the eh\_frame information was enough to do the unwind
+  properly.
+* Be permissive of badly formed elf files. Previously, any detected error
+  would result in unwinds stopping even if there is enough valid information
+  to do an unwind.
+  * The code now allows program header/section header offsets to point
+    to unreadable memory. As long as the code can find the unwind tables,
+    that is good enough.
+  * The code allows program headers/section headers to be missing.
+  * Allow a symbol table section header to point to invalid symbol table
+    values.
+* Support for the linker read-only segment option (b/109657296).
+  This is a feature of lld whereby there are two sections that
+  contain elf data. The first is read-only and contains the elf header data,
+  and the second is read-execute or execute only that
+  contains the executable code from the elf. Before this, the unwinder
+  always assumed that there was only a single read-execute section that
+  contained the elf header data and the executable code.
+* Build ID information for elf objects added. This will display the
+  NT\_GNU\_BUILD\_ID note found in elf files. This information can be used
+  to identify the exact version of a shared library to help get symbol
+  information when looking at a crash.
+* Add support for displaying the soname from an apk frame. Previously,
+  a frame map name would be only the apk, but now if the shared library
+  in the apk has set a soname, the map name will be `app.apk!libexample.so`
+  instead of only `app.apk`.
+* Minimal support for Dwarf 5. This merely treats a Dwarf 5 version
+  elf file as Dwarf 4. It does not support the new dwarf ops in Dwarf 5.
+  Since the new ops are not likely to be used very often, this allows
+  continuing to unwind even when encountering Dwarf 5 elf files.
+* Fix bug in pc handling of signal frames (b/130302288). In the previous
+  version, the pc would be wrong in the signal frame. The rest of the
+  unwind was correct, only the frame in the signal handler was incorrect
+  in Android P.
+* Detect when an elf file is not readable so that a message can be
+  displayed indicating that. This can happen when an app puts the shared
+  libraries in non-standard locations that are not readable due to
+  security restrictions (selinux rules).
+
+## Android R
+* Display the offsets for Java interpreter frames. If this frame came
+  from a non-zero offset map, no offset is printed. Previously, the
+  line would look like:
+
+    #17 pc 00500d7a  GoogleCamera.apk (com.google.camera.AndroidPriorityThread.run+10)
+
+  to:
+
+    #17 pc 00500d7a  GoogleCamera.apk (offset 0x11d0000) (com.google.camera.AndroidPriorityThread.run+10)
+* Fix bug where the load bias was set from the first PT\_LOAD program
+  header that has a zero p\_offset value. Now it is set from the first
+  executable PT\_LOAD program header. This has only ever been a problem
+  for host executables compiled for the x86\_64 architecture.
+* Switched to the libc++ demangler for function names. Previously, the
+  demangler used was not complete, so some less common demangled function
+  names would not be properly demangled or the function name would not be
+  demangled at all.
+* Fix bug in load bias handling. If the unwind information in the eh\_frame
+  or eh\_frame\_hdr does not have the same bias as the executable section,
+  and uses pc relative FDEs, the unwind will be incorrect. This tends
+  to truncate unwinds since the unwinder could not find the correct unwind
+  information for a given pc.