[NOT TO COMMIT YET] Using proc/pid/status file contents to get process metrics in linux.

base/process/process_metrics.h

Index: base/process/process_metrics.h
diff --git a/base/process/process_metrics.h b/base/process/process_metrics.h
index 54b10aaacfa2f5cfb0ab3ffc702fbc226435c325..fdf2389ce6efb1a1e044763a2484eb53e015b38f 100644
--- a/base/process/process_metrics.h
+++ b/base/process/process_metrics.h
@@ -307,6 +307,14 @@ BASE_EXPORT bool GetSystemMemoryInfo(SystemMemoryInfoKB* meminfo);
 // Exposed for testing.
 BASE_EXPORT int ParseProcStatCPU(const std::string& input);
 
+// Parses the /proc/<pid>/status file contents passed and sets |value| to the
+// size in bytes corresponding to the |field|. Only works for fields in the form
+// of "Field: value kB". Returns true on success.
+BASE_EXPORT bool ParseProcStatusAndGetField(

[Lei Zhang, 2015/10/07 16:10:54]

Why not #if defined(OS_LINUX) // and possible defined(OS_ANDROID) if needed
there?

[ssid, 2015/10/07 17:11:34]

It is expected that it will be needed in future since the seccomp-bpf will be
enabled on android and this work around will be needed.

[Lei Zhang, 2015/10/08 06:31:30]

It turned out I didn't sleep enough last night and I had trouble matching #ifs
to #endifs all day.

+    const std::string& proc_status_contents,

[Lei Zhang, 2015/10/07 16:10:54]

Why not StringPiece?

[ssid, 2015/10/07 17:11:34]

Hm yes, changed.

+    const std::string& field,
+    size_t* value);
+
 // Get the number of threads of |process| as available in /proc/<pid>/stat.
 // This should be used with care as no synchronization with running threads is
 // done. This is mostly useful to guarantee being single-threaded.