Added cgroup-awareness to Chromium (second draft)

base/process/process_metrics_linux.cc

 // Copyright (c) 2013 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/process/process_metrics.h"
 
 #include <dirent.h>
 #include <fcntl.h>
 #include <stddef.h>
 #include <stdint.h>
@@ skipping 684 matching lines @@
       meminfo->pswpin = val;
     } else if (tokens[0] == "pswpout") {
       meminfo->pswpout = val;
     } else if (tokens[0] == "pgmajfault") {
       meminfo->pgmajfault = val;
     }
   }
 
   return true;
 }
+const std::string GetCgroupMemoryPathString() {
+  std::string cgroup_memory_path = "";
+  std::string mount_info;
+  FilePath mount_file("/proc/mounts");
+  if (!ReadFileToString(mount_file, &mount_info)) {
+    DLOG(WARNING) << "Failed to open " << mount_file.value();
+    return "";
+  }
+  else{
+  for (const StringPiece& line : SplitStringPiece(
+           mount_info, "\n", KEEP_WHITESPACE, SPLIT_WANT_NONEMPTY)) {
+    std::vector<StringPiece> tokens = SplitStringPiece(
+        line, kWhitespaceASCII, TRIM_WHITESPACE, SPLIT_WANT_NONEMPTY);
+    if (tokens.size() <= 1) {
+      DLOG(WARNING) << "mount: tokens: " << tokens.size()
+                    << " malformed line: " << line.as_string();
+      continue;
+    }
+    if (tokens[0] == "cgroup"){
+       if(tokens[3].find("memory") != std::string::npos) {
+          cgroup_memory_path = tokens[1].data();
+      }
+    }
+  }
+  }
+  return cgroup_memory_path;
+}
+
+long IfOnCgroup(std::string cgroup_memory_path_string){
+  bool on_cgroup = false;
+  std::string cgroup_limits_in_bytes = "";
+  // First, cheking if we're on a cgroup
+  if (cgroup_memory_path_string == ""){
+    on_cgroup = false;}
+  else{
+    FilePath cgroup_memory_file((cgroup_memory_path_string+"memory.limit_in_bytes").c_str());
+    std::string cgroup_memory_file_info;
+    if (!ReadFileToString(cgroup_memory_file, &cgroup_memory_file_info)) {
+      on_cgroup =false;}
+    else{
+      cgroup_limits_in_bytes = cgroup_memory_file_info;
+      //file.close();
+      // TODO: is 9223372036854771712 a const?
+      if (cgroup_limits_in_bytes != "9223372036854771712"){
+        on_cgroup = true;}
+      else{
+        on_cgroup = false;}
+    }
+  }
+  if (!on_cgroup){
+    return 0;}
+  else{
+  return (atol(cgroup_limits_in_bytes.c_str()) / 1024);}
+}
 
 bool GetSystemMemoryInfo(SystemMemoryInfoKB* meminfo) {
   // Synchronously reading files in /proc and /sys are safe.
   ThreadRestrictions::ScopedAllowIO allow_io;
 
   // Used memory is: total - free - buffers - caches
   FilePath meminfo_file("/proc/meminfo");
   std::string meminfo_data;
   if (!ReadFileToString(meminfo_file, &meminfo_data)) {
     DLOG(WARNING) << "Failed to open " << meminfo_file.value();
     return false;
   }
 
   if (!ParseProcMeminfo(meminfo_data, meminfo)) {
     DLOG(WARNING) << "Failed to parse " << meminfo_file.value();
     return false;
   }
-
+  else{
+   std::string cgroup_memory_path_string = GetCgroupMemoryPathString();
+   long total_memory_kb = IfOnCgroup(cgroup_memory_path_string);
+    if (total_memory_kb > 0)
+    {
+      meminfo->total =  total_memory_kb;
+    }
+  }
 #if defined(OS_CHROMEOS)
   // Report on Chrome OS GEM object graphics memory. /run/debugfs_gpu is a
   // bind mount into /sys/kernel/debug and synchronously reading the in-memory
   // files in /sys is fast.
 #if defined(ARCH_CPU_ARM_FAMILY)
   FilePath geminfo_file("/run/debugfs_gpu/exynos_gem_objects");
 #else
   FilePath geminfo_file("/run/debugfs_gpu/i915_gem_objects");
 #endif
   std::string geminfo_data;
@@ skipping 233 matching lines @@
 #if defined(OS_LINUX)
 int ProcessMetrics::GetIdleWakeupsPerSecond() {
   uint64_t wake_ups;
   const char kWakeupStat[] = "se.statistics.nr_wakeups";
   return ReadProcSchedAndGetFieldAsUint64(process_, kWakeupStat, &wake_ups) ?
       CalculateIdleWakeupsPerSecond(wake_ups) : 0;
 }
 #endif  // defined(OS_LINUX)
 
 }  // namespace base