diff --git a/base/Android.bp b/base/Android.bp
index 7b1dc8e..121da42 100644
--- a/base/Android.bp
+++ b/base/Android.bp
@@ -42,24 +42,36 @@
             srcs: [
                 "errors_unix.cpp",
                 "properties.cpp",
+                "chrono_utils.cpp",
             ],
             cppflags: ["-Wexit-time-destructors"],
             sanitize: {
                 misc_undefined: ["integer"],
             },
+
         },
         darwin: {
-            srcs: ["errors_unix.cpp"],
+            srcs: [
+                "chrono_utils.cpp",
+                "errors_unix.cpp",
+            ],
             cppflags: ["-Wexit-time-destructors"],
         },
         linux_bionic: {
-            srcs: ["errors_unix.cpp"],
+            srcs: [
+                "chrono_utils.cpp",
+                "errors_unix.cpp",
+            ],
             cppflags: ["-Wexit-time-destructors"],
             enabled: true,
         },
         linux: {
-            srcs: ["errors_unix.cpp"],
+            srcs: [
+                "chrono_utils.cpp",
+                "errors_unix.cpp",
+            ],
             cppflags: ["-Wexit-time-destructors"],
+            host_ldlibs: ["-lrt"],
         },
         windows: {
             srcs: [
@@ -92,11 +104,18 @@
     ],
     target: {
         android: {
-            srcs: ["properties_test.cpp"],
+            srcs: [
+                "chrono_utils_test.cpp",
+                "properties_test.cpp"
+            ],
             sanitize: {
                 misc_undefined: ["integer"],
             },
         },
+        linux: {
+            srcs: ["chrono_utils_test.cpp"],
+            host_ldlibs: ["-lrt"],
+        },
         windows: {
             srcs: ["utf8_test.cpp"],
             enabled: true,
diff --git a/base/chrono_utils.cpp b/base/chrono_utils.cpp
new file mode 100644
index 0000000..5eedf3b
--- /dev/null
+++ b/base/chrono_utils.cpp
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2017 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 "android-base/chrono_utils.h"
+
+#include <time.h>
+
+namespace android {
+namespace base {
+
+boot_clock::time_point boot_clock::now() {
+#ifdef __ANDROID__
+  timespec ts;
+  clock_gettime(CLOCK_BOOTTIME, &ts);
+  return boot_clock::time_point(std::chrono::seconds(ts.tv_sec) +
+                                std::chrono::nanoseconds(ts.tv_nsec));
+#else
+  // Darwin does not support clock_gettime.
+  return boot_clock::time_point();
+#endif  // __ANDROID__
+}
+
+}  // namespace base
+}  // namespace android
diff --git a/base/chrono_utils_test.cpp b/base/chrono_utils_test.cpp
new file mode 100644
index 0000000..057132d
--- /dev/null
+++ b/base/chrono_utils_test.cpp
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2017 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 "android-base/chrono_utils.h"
+
+#include <time.h>
+
+#include <chrono>
+
+#include <gtest/gtest.h>
+
+namespace android {
+namespace base {
+
+std::chrono::seconds GetBootTimeSeconds() {
+  struct timespec now;
+  clock_gettime(CLOCK_BOOTTIME, &now);
+
+  auto now_tp = boot_clock::time_point(std::chrono::seconds(now.tv_sec) +
+                                       std::chrono::nanoseconds(now.tv_nsec));
+  return std::chrono::duration_cast<std::chrono::seconds>(now_tp.time_since_epoch());
+}
+
+// Tests (at least) the seconds accuracy of the boot_clock::now() method.
+TEST(ChronoUtilsTest, BootClockNowSeconds) {
+  auto now = GetBootTimeSeconds();
+  auto boot_seconds =
+      std::chrono::duration_cast<std::chrono::seconds>(boot_clock::now().time_since_epoch());
+  EXPECT_EQ(now, boot_seconds);
+}
+
+}  // namespace base
+}  // namespace android
\ No newline at end of file
diff --git a/base/include/android-base/chrono_utils.h b/base/include/android-base/chrono_utils.h
new file mode 100644
index 0000000..0086425
--- /dev/null
+++ b/base/include/android-base/chrono_utils.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef ANDROID_BASE_CHRONO_UTILS_H
+#define ANDROID_BASE_CHRONO_UTILS_H
+
+#include <chrono>
+
+namespace android {
+namespace base {
+
+// A std::chrono clock based on CLOCK_BOOTTIME.
+class boot_clock {
+ public:
+  typedef std::chrono::nanoseconds duration;
+  typedef std::chrono::time_point<boot_clock, duration> time_point;
+
+  static time_point now();
+};
+
+}  // namespace base
+}  // namespace android
+
+#endif  // ANDROID_BASE_CHRONO_UTILS_H
diff --git a/bootstat/Android.bp b/bootstat/Android.bp
index f744ad1..95c9af5 100644
--- a/bootstat/Android.bp
+++ b/bootstat/Android.bp
@@ -16,7 +16,6 @@
 
 bootstat_lib_src_files = [
     "boot_event_record_store.cpp",
-    "uptime_parser.cpp",
 ]
 
 cc_defaults {
diff --git a/bootstat/boot_event_record_store.cpp b/bootstat/boot_event_record_store.cpp
index 2648594..99d9405 100644
--- a/bootstat/boot_event_record_store.cpp
+++ b/bootstat/boot_event_record_store.cpp
@@ -20,13 +20,16 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <utime.h>
+
+#include <chrono>
 #include <cstdlib>
 #include <string>
 #include <utility>
+
+#include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/parseint.h>
-#include "uptime_parser.h"
 
 namespace {
 
@@ -55,7 +58,9 @@
 }
 
 void BootEventRecordStore::AddBootEvent(const std::string& event) {
-  AddBootEventWithValue(event, bootstat::ParseUptime());
+    auto uptime = std::chrono::duration_cast<std::chrono::seconds>(
+        android::base::boot_clock::now().time_since_epoch());
+    AddBootEventWithValue(event, uptime.count());
 }
 
 // The implementation of AddBootEventValue makes use of the mtime file
diff --git a/bootstat/boot_event_record_store_test.cpp b/bootstat/boot_event_record_store_test.cpp
index 90f6513..d98169b 100644
--- a/bootstat/boot_event_record_store_test.cpp
+++ b/bootstat/boot_event_record_store_test.cpp
@@ -21,15 +21,18 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <unistd.h>
+
+#include <chrono>
 #include <cstdint>
 #include <cstdlib>
+
+#include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/test_utils.h>
 #include <android-base/unique_fd.h>
-#include <gtest/gtest.h>
 #include <gmock/gmock.h>
-#include "uptime_parser.h"
+#include <gtest/gtest.h>
 
 using testing::UnorderedElementsAreArray;
 
@@ -89,6 +92,13 @@
   rmdir(path.c_str());
 }
 
+// Returns the time in seconds since boot.
+time_t GetUptimeSeconds() {
+    return std::chrono::duration_cast<std::chrono::seconds>(
+               android::base::boot_clock::now().time_since_epoch())
+        .count();
+}
+
 class BootEventRecordStoreTest : public ::testing::Test {
  public:
   BootEventRecordStoreTest() {
@@ -126,7 +136,7 @@
   BootEventRecordStore store;
   store.SetStorePath(GetStorePathForTesting());
 
-  time_t uptime = bootstat::ParseUptime();
+  time_t uptime = GetUptimeSeconds();
   ASSERT_NE(-1, uptime);
 
   store.AddBootEvent("cenozoic");
@@ -141,7 +151,7 @@
   BootEventRecordStore store;
   store.SetStorePath(GetStorePathForTesting());
 
-  time_t uptime = bootstat::ParseUptime();
+  time_t uptime = GetUptimeSeconds();
   ASSERT_NE(-1, uptime);
 
   store.AddBootEvent("cretaceous");
diff --git a/bootstat/bootstat.cpp b/bootstat/bootstat.cpp
index a4cc5f2..6f25d96 100644
--- a/bootstat/bootstat.cpp
+++ b/bootstat/bootstat.cpp
@@ -21,6 +21,7 @@
 #include <getopt.h>
 #include <unistd.h>
 
+#include <chrono>
 #include <cmath>
 #include <cstddef>
 #include <cstdio>
@@ -30,15 +31,15 @@
 #include <string>
 #include <vector>
 
-#include <android/log.h>
+#include <android-base/chrono_utils.h>
 #include <android-base/logging.h>
 #include <android-base/parseint.h>
 #include <android-base/strings.h>
+#include <android/log.h>
 #include <cutils/properties.h>
 #include <metricslogger/metrics_logger.h>
 
 #include "boot_event_record_store.h"
-#include "uptime_parser.h"
 
 namespace {
 
@@ -255,7 +256,8 @@
   BootEventRecordStore boot_event_store;
   BootEventRecordStore::BootEventRecord record;
 
-  time_t uptime = bootstat::ParseUptime();
+  auto uptime = std::chrono::duration_cast<std::chrono::seconds>(
+      android::base::boot_clock::now().time_since_epoch());
   time_t current_time_utc = time(nullptr);
 
   if (boot_event_store.GetBootEvent("last_boot_time_utc", &record)) {
@@ -282,22 +284,21 @@
     // Log the amount of time elapsed until the device is decrypted, which
     // includes the variable amount of time the user takes to enter the
     // decryption password.
-    boot_event_store.AddBootEventWithValue("boot_decryption_complete", uptime);
+    boot_event_store.AddBootEventWithValue("boot_decryption_complete", uptime.count());
 
     // Subtract the decryption time to normalize the boot cycle timing.
-    time_t boot_complete = uptime - record.second;
+    std::chrono::seconds boot_complete = std::chrono::seconds(uptime.count() - record.second);
     boot_event_store.AddBootEventWithValue(boot_complete_prefix + "_post_decrypt",
-                                           boot_complete);
-
+                                           boot_complete.count());
 
   } else {
-    boot_event_store.AddBootEventWithValue(boot_complete_prefix + "_no_encryption",
-                                           uptime);
+      boot_event_store.AddBootEventWithValue(boot_complete_prefix + "_no_encryption",
+                                             uptime.count());
   }
 
   // Record the total time from device startup to boot complete, regardless of
   // encryption state.
-  boot_event_store.AddBootEventWithValue(boot_complete_prefix, uptime);
+  boot_event_store.AddBootEventWithValue(boot_complete_prefix, uptime.count());
 
   RecordInitBootTimeProp(&boot_event_store, "ro.boottime.init");
   RecordInitBootTimeProp(&boot_event_store, "ro.boottime.init.selinux");
diff --git a/bootstat/uptime_parser.cpp b/bootstat/uptime_parser.cpp
deleted file mode 100644
index 7c2034c..0000000
--- a/bootstat/uptime_parser.cpp
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- * Copyright (C) 2016 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 "uptime_parser.h"
-
-#include <time.h>
-#include <cstdlib>
-#include <string>
-#include <android-base/file.h>
-#include <android-base/logging.h>
-
-namespace bootstat {
-
-time_t ParseUptime() {
-  std::string uptime_str;
-  if (!android::base::ReadFileToString("/proc/uptime", &uptime_str)) {
-    PLOG(ERROR) << "Failed to read /proc/uptime";
-    return -1;
-  }
-
-  // Cast intentionally rounds down.
-  return static_cast<time_t>(strtod(uptime_str.c_str(), NULL));
-}
-
-}  // namespace bootstat
\ No newline at end of file
diff --git a/bootstat/uptime_parser.h b/bootstat/uptime_parser.h
deleted file mode 100644
index 756ae9b..0000000
--- a/bootstat/uptime_parser.h
+++ /dev/null
@@ -1,29 +0,0 @@
-/*
- * Copyright (C) 2016 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.
- */
-
-#ifndef UPTIME_PARSER_H_
-#define UPTIME_PARSER_H_
-
-#include <time.h>
-
-namespace bootstat {
-
-// Returns the number of seconds the system has been on since reboot.
-time_t ParseUptime();
-
-}  // namespace bootstat
-
-#endif  // UPTIME_PARSER_H_
\ No newline at end of file
diff --git a/fs_mgr/fs_mgr_fstab.cpp b/fs_mgr/fs_mgr_fstab.cpp
index 720ec03..0406efd 100644
--- a/fs_mgr/fs_mgr_fstab.cpp
+++ b/fs_mgr/fs_mgr_fstab.cpp
@@ -625,17 +625,6 @@
     return fstab;
 }
 
-/* combines fstab entries passed in from device tree with
- * the ones found from fstab_path
- */
-struct fstab *fs_mgr_read_fstab_with_dt(const char *fstab_path)
-{
-    struct fstab *fstab_dt = fs_mgr_read_fstab_dt();
-    struct fstab *fstab = fs_mgr_read_fstab(fstab_path);
-
-    return in_place_merge(fstab_dt, fstab);
-}
-
 /*
  * tries to load default fstab.<hardware> file from /odm/etc, /vendor/etc
  * or /. loads the first one found and also combines fstab entries passed
@@ -658,7 +647,12 @@
         LWARNING << __FUNCTION__ << "(): failed to find device hardware name";
     }
 
-    return fs_mgr_read_fstab_with_dt(default_fstab.c_str());
+    // combines fstab entries passed in from device tree with
+    // the ones found from default_fstab file
+    struct fstab *fstab_dt = fs_mgr_read_fstab_dt();
+    struct fstab *fstab = fs_mgr_read_fstab(default_fstab.c_str());
+
+    return in_place_merge(fstab_dt, fstab);
 }
 
 void fs_mgr_free_fstab(struct fstab *fstab)
diff --git a/fs_mgr/include/fs_mgr.h b/fs_mgr/include/fs_mgr.h
index e4aeb48..4b626de 100644
--- a/fs_mgr/include/fs_mgr.h
+++ b/fs_mgr/include/fs_mgr.h
@@ -88,7 +88,6 @@
 struct fstab *fs_mgr_read_fstab_default();
 struct fstab *fs_mgr_read_fstab_dt();
 struct fstab *fs_mgr_read_fstab(const char *fstab_path);
-struct fstab *fs_mgr_read_fstab_with_dt(const char *fstab_path);
 void fs_mgr_free_fstab(struct fstab *fstab);
 
 #define FS_MGR_MNTALL_DEV_FILE_ENCRYPTED 5
diff --git a/init/init.cpp b/init/init.cpp
index 6f3b3a6..e14034f 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -40,6 +40,7 @@
 #include <selinux/label.h>
 #include <selinux/android.h>
 
+#include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/properties.h>
 #include <android-base/stringprintf.h>
@@ -69,6 +70,7 @@
 #include "util.h"
 #include "watchdogd.h"
 
+using android::base::boot_clock;
 using android::base::GetProperty;
 using android::base::StringPrintf;
 
diff --git a/init/service.cpp b/init/service.cpp
index 3db34db..e89de9a 100644
--- a/init/service.cpp
+++ b/init/service.cpp
@@ -32,6 +32,7 @@
 
 #include <selinux/selinux.h>
 
+#include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/parseint.h>
 #include <android-base/properties.h>
@@ -48,6 +49,7 @@
 #include "property_service.h"
 #include "util.h"
 
+using android::base::boot_clock;
 using android::base::ParseInt;
 using android::base::StringPrintf;
 using android::base::WriteStringToFile;
diff --git a/init/service.h b/init/service.h
index f08a03f..d84ce02 100644
--- a/init/service.h
+++ b/init/service.h
@@ -26,6 +26,8 @@
 #include <string>
 #include <vector>
 
+#include <android-base/chrono_utils.h>
+
 #include "action.h"
 #include "capabilities.h"
 #include "descriptors.h"
@@ -144,8 +146,8 @@
 
     unsigned flags_;
     pid_t pid_;
-    boot_clock::time_point time_started_; // time of last start
-    boot_clock::time_point time_crashed_; // first crash within inspection window
+    android::base::boot_clock::time_point time_started_;  // time of last start
+    android::base::boot_clock::time_point time_crashed_;  // first crash within inspection window
     int crash_count_;                     // number of times crashed within window
 
     uid_t uid_;
diff --git a/init/util.cpp b/init/util.cpp
index 73d97ed..3f8f244 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -52,6 +52,8 @@
 #include "reboot.h"
 #include "util.h"
 
+using android::base::boot_clock;
+
 static unsigned int do_decode_uid(const char *s)
 {
     unsigned int v;
@@ -198,13 +200,6 @@
     return success;
 }
 
-boot_clock::time_point boot_clock::now() {
-  timespec ts;
-  clock_gettime(CLOCK_BOOTTIME, &ts);
-  return boot_clock::time_point(std::chrono::seconds(ts.tv_sec) +
-                                std::chrono::nanoseconds(ts.tv_nsec));
-}
-
 int mkdir_recursive(const char *pathname, mode_t mode)
 {
     char buf[128];
diff --git a/init/util.h b/init/util.h
index 81c64d7..23509d3 100644
--- a/init/util.h
+++ b/init/util.h
@@ -25,8 +25,11 @@
 #include <ostream>
 #include <string>
 
+#include <android-base/chrono_utils.h>
+
 #define COLDBOOT_DONE "/dev/.coldboot_done"
 
+using android::base::boot_clock;
 using namespace std::chrono_literals;
 
 int create_socket(const char *name, int type, mode_t perm,
@@ -35,32 +38,22 @@
 bool read_file(const char* path, std::string* content);
 bool write_file(const char* path, const char* content);
 
-// A std::chrono clock based on CLOCK_BOOTTIME.
-class boot_clock {
- public:
-  typedef std::chrono::nanoseconds duration;
-  typedef std::chrono::time_point<boot_clock, duration> time_point;
-  static constexpr bool is_steady = true;
-
-  static time_point now();
-};
-
 class Timer {
- public:
-  Timer() : start_(boot_clock::now()) {
-  }
+  public:
+    Timer() : start_(boot_clock::now()) {}
 
-  double duration_s() const {
-    typedef std::chrono::duration<double> double_duration;
-    return std::chrono::duration_cast<double_duration>(boot_clock::now() - start_).count();
-  }
+    double duration_s() const {
+        typedef std::chrono::duration<double> double_duration;
+        return std::chrono::duration_cast<double_duration>(boot_clock::now() - start_).count();
+    }
 
-  int64_t duration_ms() const {
-    return std::chrono::duration_cast<std::chrono::milliseconds>(boot_clock::now() - start_).count();
-  }
+    int64_t duration_ms() const {
+        return std::chrono::duration_cast<std::chrono::milliseconds>(boot_clock::now() - start_)
+            .count();
+    }
 
- private:
-  boot_clock::time_point start_;
+  private:
+    android::base::boot_clock::time_point start_;
 };
 
 std::ostream& operator<<(std::ostream& os, const Timer& t);
diff --git a/libcutils/include/private/android_filesystem_config.h b/libcutils/include/private/android_filesystem_config.h
index 0037f15..3eeb9dc 100644
--- a/libcutils/include/private/android_filesystem_config.h
+++ b/libcutils/include/private/android_filesystem_config.h
@@ -130,6 +130,7 @@
 #define AID_MEDIA_OBB 1059       /* GID for OBB files on internal media storage */
 #define AID_ESE 1060             /* embedded secure element (eSE) subsystem */
 #define AID_OTA_UPDATE 1061      /* resource tracking UID for OTA updates */
+#define AID_DISK_RESERVED 1062   /* GID that has access to reserved disk space */
 /* Changes to this file must be made in AOSP, *not* in internal branches. */
 
 #define AID_SHELL 2000 /* adb and debug shell user */
diff --git a/liblog/tests/liblog_benchmark.cpp b/liblog/tests/liblog_benchmark.cpp
index 3f79552..c4bf959 100644
--- a/liblog/tests/liblog_benchmark.cpp
+++ b/liblog/tests/liblog_benchmark.cpp
@@ -527,11 +527,13 @@
 /*
  *	Measure the time it takes to submit the android event logging call
  * using discrete acquisition (StartBenchmarkTiming() -> StopBenchmarkTiming())
- * under light load. Expect this to be a dozen or so syscall periods (40us)
+ * under light load. Expect this to be a long path to logger to convert the
+ * unknown tag (0) into a tagname (less than 200us).
  */
 static void BM_log_event_overhead(int iters) {
   for (unsigned long long i = 0; i < (unsigned)iters; ++i) {
     StartBenchmarkTiming();
+    // log tag number 0 is not known, nor shall it ever be known
     __android_log_btwrite(0, EVENT_TYPE_LONG, &i, sizeof(i));
     StopBenchmarkTiming();
     logd_yield();
@@ -539,6 +541,28 @@
 }
 BENCHMARK(BM_log_event_overhead);
 
+/*
+ *	Measure the time it takes to submit the android event logging call
+ * using discrete acquisition (StartBenchmarkTiming() -> StopBenchmarkTiming())
+ * under light load with a known logtag.  Expect this to be a dozen or so
+ * syscall periods (less than 40us)
+ */
+static void BM_log_event_overhead_42(int iters) {
+  for (unsigned long long i = 0; i < (unsigned)iters; ++i) {
+    StartBenchmarkTiming();
+    // In system/core/logcat/event.logtags:
+    // # These are used for testing, do not modify without updating
+    // # tests/framework-tests/src/android/util/EventLogFunctionalTest.java.
+    // # system/core/liblog/tests/liblog_benchmark.cpp
+    // # system/core/liblog/tests/liblog_test.cpp
+    // 42    answer (to life the universe etc|3)
+    __android_log_btwrite(42, EVENT_TYPE_LONG, &i, sizeof(i));
+    StopBenchmarkTiming();
+    logd_yield();
+  }
+}
+BENCHMARK(BM_log_event_overhead_42);
+
 static void BM_log_event_overhead_null(int iters) {
   set_log_null();
   BM_log_event_overhead(iters);
diff --git a/logcat/event.logtags b/logcat/event.logtags
index 909f8e2..9f05351 100644
--- a/logcat/event.logtags
+++ b/logcat/event.logtags
@@ -36,6 +36,8 @@
 
 # These are used for testing, do not modify without updating
 # tests/framework-tests/src/android/util/EventLogFunctionalTest.java.
+# system/core/liblog/tests/liblog_benchmark.cpp
+# system/core/liblog/tests/liblog_test.cpp
 42    answer (to life the universe etc|3)
 314   pi
 2718  e
diff --git a/logd/LogBuffer.cpp b/logd/LogBuffer.cpp
index 86ea6b4..0984e81 100644
--- a/logd/LogBuffer.cpp
+++ b/logd/LogBuffer.cpp
@@ -109,11 +109,11 @@
 
 LogBuffer::LogBuffer(LastLogTimes* times)
     : monotonic(android_log_clockid() == CLOCK_MONOTONIC), mTimes(*times) {
-    pthread_mutex_init(&mLogElementsLock, NULL);
+    pthread_mutex_init(&mLogElementsLock, nullptr);
 
     log_id_for_each(i) {
-        lastLoggedElements[i] = NULL;
-        droppedElements[i] = NULL;
+        lastLoggedElements[i] = nullptr;
+        droppedElements[i] = nullptr;
     }
 
     init();
@@ -196,7 +196,7 @@
         new LogBufferElement(log_id, realtime, uid, pid, tid, msg, len);
     if (log_id != LOG_ID_SECURITY) {
         int prio = ANDROID_LOG_INFO;
-        const char* tag = NULL;
+        const char* tag = nullptr;
         if (log_id == LOG_ID_EVENTS) {
             tag = tagToName(elem->getTag());
         } else {
@@ -222,24 +222,24 @@
         //
         // State Init
         //     incoming:
-        //         dropped = NULL
-        //         currentLast = NULL;
+        //         dropped = nullptr
+        //         currentLast = nullptr;
         //         elem = incoming message
         //     outgoing:
-        //         dropped = NULL -> State 0
+        //         dropped = nullptr -> State 0
         //         currentLast = copy of elem
         //         log elem
         // State 0
         //     incoming:
         //         count = 0
-        //         dropped = NULL
+        //         dropped = nullptr
         //         currentLast = copy of last message
         //         elem = incoming message
         //     outgoing: if match != DIFFERENT
         //         dropped = copy of first identical message -> State 1
         //         currentLast = reference to elem
         //     break: if match == DIFFERENT
-        //         dropped = NULL -> State 0
+        //         dropped = nullptr -> State 0
         //         delete copy of last message (incoming currentLast)
         //         currentLast = copy of elem
         //         log elem
@@ -266,7 +266,7 @@
         //             currentLast = reference to elem, sum liblog.
         //     break: if match == DIFFERENT
         //         delete dropped
-        //         dropped = NULL -> State 0
+        //         dropped = nullptr -> State 0
         //         log reference to last held-back (currentLast)
         //         currentLast = copy of elem
         //         log elem
@@ -285,7 +285,7 @@
         //         currentLast = reference to elem
         //     break: if match == DIFFERENT
         //         log dropped (chatty message)
-        //         dropped = NULL -> State 0
+        //         dropped = nullptr -> State 0
         //         log reference to last held-back (currentLast)
         //         currentLast = copy of elem
         //         log elem
@@ -350,7 +350,7 @@
             } else {           // State 1
                 delete dropped;
             }
-            droppedElements[log_id] = NULL;
+            droppedElements[log_id] = nullptr;
             log(currentLast);  // report last message in the series
         } else {               // State 0
             delete currentLast;
@@ -654,7 +654,7 @@
 // mLogElementsLock must be held when this function is called.
 //
 bool LogBuffer::prune(log_id_t id, unsigned long pruneRows, uid_t caller_uid) {
-    LogTimeEntry* oldest = NULL;
+    LogTimeEntry* oldest = nullptr;
     bool busy = false;
     bool clearAll = pruneRows == ULONG_MAX;
 
@@ -1076,9 +1076,11 @@
     return retval;
 }
 
-log_time LogBuffer::flushTo(
-    SocketClient* reader, const log_time& start, bool privileged, bool security,
-    int (*filter)(const LogBufferElement* element, void* arg), void* arg) {
+log_time LogBuffer::flushTo(SocketClient* reader, const log_time& start,
+                            pid_t* lastTid, bool privileged, bool security,
+                            int (*filter)(const LogBufferElement* element,
+                                          void* arg),
+                            void* arg) {
     LogBufferElementCollection::iterator it;
     uid_t uid = reader->getUid();
 
@@ -1107,9 +1109,6 @@
     }
 
     log_time max = start;
-    // Help detect if the valid message before is from the same source so
-    // we can differentiate chatty filter types.
-    pid_t lastTid[LOG_ID_MAX] = { 0 };
 
     for (; it != mLogElements.end(); ++it) {
         LogBufferElement* element = *it;
@@ -1137,14 +1136,17 @@
             }
         }
 
-        bool sameTid = lastTid[element->getLogId()] == element->getTid();
-        // Dropped (chatty) immediately following a valid log from the
-        // same source in the same log buffer indicates we have a
-        // multiple identical squash.  chatty that differs source
-        // is due to spam filter.  chatty to chatty of different
-        // source is also due to spam filter.
-        lastTid[element->getLogId()] =
-            (element->getDropped() && !sameTid) ? 0 : element->getTid();
+        bool sameTid = false;
+        if (lastTid) {
+            sameTid = lastTid[element->getLogId()] == element->getTid();
+            // Dropped (chatty) immediately following a valid log from the
+            // same source in the same log buffer indicates we have a
+            // multiple identical squash.  chatty that differs source
+            // is due to spam filter.  chatty to chatty of different
+            // source is also due to spam filter.
+            lastTid[element->getLogId()] =
+                (element->getDropped() && !sameTid) ? 0 : element->getTid();
+        }
 
         pthread_mutex_unlock(&mLogElementsLock);
 
diff --git a/logd/LogBuffer.h b/logd/LogBuffer.h
index fcf6b9a..19d11cb 100644
--- a/logd/LogBuffer.h
+++ b/logd/LogBuffer.h
@@ -115,11 +115,15 @@
 
     int log(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid,
             const char* msg, unsigned short len);
+    // lastTid is an optional context to help detect if the last previous
+    // valid message was from the same source so we can differentiate chatty
+    // filter types (identical or expired)
     log_time flushTo(SocketClient* writer, const log_time& start,
+                     pid_t* lastTid,  // &lastTid[LOG_ID_MAX] or nullptr
                      bool privileged, bool security,
                      int (*filter)(const LogBufferElement* element,
-                                   void* arg) = NULL,
-                     void* arg = NULL);
+                                   void* arg) = nullptr,
+                     void* arg = nullptr);
 
     bool clear(log_id_t id, uid_t uid = AID_ROOT);
     unsigned long getSize(log_id_t id);
diff --git a/logd/LogReader.cpp b/logd/LogReader.cpp
index 620d4d0..af19279 100644
--- a/logd/LogReader.cpp
+++ b/logd/LogReader.cpp
@@ -182,7 +182,7 @@
         } logFindStart(pid, logMask, sequence,
                        logbuf().isMonotonic() && android::isMonotonic(start));
 
-        logbuf().flushTo(cli, sequence, FlushCommand::hasReadLogs(cli),
+        logbuf().flushTo(cli, sequence, nullptr, FlushCommand::hasReadLogs(cli),
                          FlushCommand::hasSecurityLogs(cli),
                          logFindStart.callback, &logFindStart);
 
diff --git a/logd/LogTimes.cpp b/logd/LogTimes.cpp
index 04e531f..ccc550a 100644
--- a/logd/LogTimes.cpp
+++ b/logd/LogTimes.cpp
@@ -15,6 +15,7 @@
  */
 
 #include <errno.h>
+#include <string.h>
 #include <sys/prctl.h>
 
 #include <private/android_logger.h>
@@ -47,7 +48,8 @@
       mEnd(log_time(android_log_clockid())) {
     mTimeout.tv_sec = timeout / NS_PER_SEC;
     mTimeout.tv_nsec = timeout % NS_PER_SEC;
-    pthread_cond_init(&threadTriggeredCondition, NULL);
+    memset(mLastTid, 0, sizeof(mLastTid));
+    pthread_cond_init(&threadTriggeredCondition, nullptr);
     cleanSkip_Locked();
 }
 
@@ -98,7 +100,7 @@
             it++;
         }
 
-        me->mClient = NULL;
+        me->mClient = nullptr;
         reader.release(client);
     }
 
@@ -122,7 +124,7 @@
     SocketClient* client = me->mClient;
     if (!client) {
         me->error();
-        return NULL;
+        return nullptr;
     }
 
     LogBuffer& logbuf = me->mReader.logbuf();
@@ -151,12 +153,12 @@
         unlock();
 
         if (me->mTail) {
-            logbuf.flushTo(client, start, privileged, security, FilterFirstPass,
-                           me);
+            logbuf.flushTo(client, start, nullptr, privileged, security,
+                           FilterFirstPass, me);
             me->leadingDropped = true;
         }
-        start = logbuf.flushTo(client, start, privileged, security,
-                               FilterSecondPass, me);
+        start = logbuf.flushTo(client, start, me->mLastTid, privileged,
+                               security, FilterSecondPass, me);
 
         lock();
 
@@ -182,7 +184,7 @@
 
     pthread_cleanup_pop(true);
 
-    return NULL;
+    return nullptr;
 }
 
 // A first pass to count the number of elements
@@ -281,7 +283,5 @@
 }
 
 void LogTimeEntry::cleanSkip_Locked(void) {
-    for (log_id_t i = LOG_ID_MIN; i < LOG_ID_MAX; i = (log_id_t)(i + 1)) {
-        skipAhead[i] = 0;
-    }
+    memset(skipAhead, 0, sizeof(skipAhead));
 }
diff --git a/logd/LogTimes.h b/logd/LogTimes.h
index 9a3ddab..ec8252e 100644
--- a/logd/LogTimes.h
+++ b/logd/LogTimes.h
@@ -44,6 +44,7 @@
     const unsigned int mLogMask;
     const pid_t mPid;
     unsigned int skipAhead[LOG_ID_MAX];
+    pid_t mLastTid[LOG_ID_MAX];
     unsigned long mCount;
     unsigned long mTail;
     unsigned long mIndex;
diff --git a/logd/tests/logd_test.cpp b/logd/tests/logd_test.cpp
index ddff393..d0101ed 100644
--- a/logd/tests/logd_test.cpp
+++ b/logd/tests/logd_test.cpp
@@ -426,7 +426,7 @@
                     " BM_log_maximum_retry"
                     " BM_log_maximum"
                     " BM_clock_overhead"
-                    " BM_log_overhead"
+                    " BM_log_print_overhead"
                     " BM_log_latency"
                     " BM_log_delay",
                     "r")));
@@ -434,13 +434,13 @@
     char buffer[5120];
 
     static const char* benchmarks[] = {
-        "BM_log_maximum_retry ", "BM_log_maximum ", "BM_clock_overhead ",
-        "BM_log_overhead ",      "BM_log_latency ", "BM_log_delay "
+        "BM_log_maximum_retry ",  "BM_log_maximum ", "BM_clock_overhead ",
+        "BM_log_print_overhead ", "BM_log_latency ", "BM_log_delay "
     };
     static const unsigned int log_maximum_retry = 0;
     static const unsigned int log_maximum = 1;
     static const unsigned int clock_overhead = 2;
-    static const unsigned int log_overhead = 3;
+    static const unsigned int log_print_overhead = 3;
     static const unsigned int log_latency = 4;
     static const unsigned int log_delay = 5;
 
@@ -469,21 +469,23 @@
     }
 
     EXPECT_GE(200000UL, ns[log_maximum_retry]);  // 104734 user
+    EXPECT_NE(0UL, ns[log_maximum_retry]);       // failure to parse
 
     EXPECT_GE(90000UL, ns[log_maximum]);  // 46913 user
+    EXPECT_NE(0UL, ns[log_maximum]);      // failure to parse
 
     EXPECT_GE(4096UL, ns[clock_overhead]);  // 4095
+    EXPECT_NE(0UL, ns[clock_overhead]);     // failure to parse
 
-    EXPECT_GE(250000UL, ns[log_overhead]);  // 126886 user
+    EXPECT_GE(250000UL, ns[log_print_overhead]);  // 126886 user
+    EXPECT_NE(0UL, ns[log_print_overhead]);       // failure to parse
 
     EXPECT_GE(10000000UL,
               ns[log_latency]);  // 1453559 user space (background cgroup)
+    EXPECT_NE(0UL, ns[log_latency]);  // failure to parse
 
     EXPECT_GE(20000000UL, ns[log_delay]);  // 10500289 user
-
-    for (unsigned i = 0; i < arraysize(ns); ++i) {
-        EXPECT_NE(0UL, ns[i]);
-    }
+    EXPECT_NE(0UL, ns[log_delay]);         // failure to parse
 
     alloc_statistics(&buf, &len);