Update from https://crrev.com/333737

base/trace_event/process_memory_totals_dump_provider.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/trace_event/process_memory_totals_dump_provider.h"
 
 #include "base/process/process_metrics.h"
 #include "base/trace_event/process_memory_dump.h"
 #include "base/trace_event/process_memory_totals.h"
 
+#if defined(OS_LINUX) || defined(OS_ANDROID)
+#include <fcntl.h>
+
+#include "base/files/file_util.h"
+
+namespace {
+bool kernel_supports_rss_peak_reset = true;
+const char kClearPeakRssCommand[] = "5";
+}
+#endif
+
 namespace base {
 namespace trace_event {
 
 // static
 uint64 ProcessMemoryTotalsDumpProvider::rss_bytes_for_testing = 0;
 
 namespace {
 
 ProcessMetrics* CreateProcessMetricsForCurrentProcess() {
 #if !defined(OS_MACOSX) || defined(OS_IOS)
@@ skipping 19 matching lines @@
 ProcessMemoryTotalsDumpProvider::~ProcessMemoryTotalsDumpProvider() {
 }
 
 // Called at trace dump point time. Creates a snapshot the memory counters for
 // the current process.
 bool ProcessMemoryTotalsDumpProvider::OnMemoryDump(ProcessMemoryDump* pmd) {
   const uint64 rss_bytes = rss_bytes_for_testing
                                ? rss_bytes_for_testing
                                : process_metrics_->GetWorkingSetSize();
 
+  uint64 peak_rss_bytes = 0;
+
+#if !defined(OS_IOS)
+  peak_rss_bytes = process_metrics_->GetPeakWorkingSetSize();
+#if defined(OS_LINUX) || defined(OS_ANDROID)
+  if (kernel_supports_rss_peak_reset) {
+    // TODO(ssid): Fix crbug.com/461788 to write to the file from sandboxed
+    // processes.
+    int clear_refs_fd = open("/proc/self/clear_refs", O_WRONLY);
+    if (clear_refs_fd > 0 &&
+        WriteFileDescriptor(clear_refs_fd, kClearPeakRssCommand,
+                            sizeof(kClearPeakRssCommand))) {
+      pmd->process_totals()->set_is_peak_rss_resetable(true);
+    } else {
+      kernel_supports_rss_peak_reset = false;
+    }
+    close(clear_refs_fd);
+  }
+#endif  // defined(OS_LINUX) || defined(OS_ANDROID)
+#endif  // !defined(OS_IOS)
+
   if (rss_bytes > 0) {
     pmd->process_totals()->set_resident_set_bytes(rss_bytes);
+    pmd->process_totals()->set_peak_resident_set_bytes(peak_rss_bytes);
     pmd->set_has_process_totals();
     return true;
   }
 
   return false;
 }
 
 }  // namespace trace_event
 }  // namespace base