Clean up base/process/process_metrics_linux.cc.

base/process/process_metrics.h

 // 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.
 
 // This file contains routines for gathering resource statistics for processes
 // running on the system.
 
 #ifndef BASE_PROCESS_PROCESS_METRICS_H_
 #define BASE_PROCESS_PROCESS_METRICS_H_
 
@@ skipping 374 matching lines @@
 // Exposed for memory debugging widget.
 BASE_EXPORT bool GetSystemMemoryInfo(SystemMemoryInfoKB* meminfo);
 
 #endif  // defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX) ||
         // defined(OS_ANDROID)
 
 #if defined(OS_LINUX) || defined(OS_ANDROID) || defined(OS_AIX)
 // Parse the data found in /proc/<pid>/stat and return the sum of the
 // CPU-related ticks.  Returns -1 on parse error.
 // Exposed for testing.
-BASE_EXPORT int ParseProcStatCPU(const std::string& input);
+BASE_EXPORT int ParseProcStatCPU(StringPiece input);
 
 // 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.
 // Returns 0 on failure.
 BASE_EXPORT int GetNumberOfThreads(ProcessHandle process);
 
 // /proc/self/exe refers to the current executable.
 BASE_EXPORT extern const char kProcSelfExe[];
 
 // Parses a string containing the contents of /proc/meminfo
 // returns true on success or false for a parsing error
-BASE_EXPORT bool ParseProcMeminfo(const std::string& input,
+// Exposed for testing.
+BASE_EXPORT bool ParseProcMeminfo(StringPiece input,
                                   SystemMemoryInfoKB* meminfo);
 
 // Parses a string containing the contents of /proc/vmstat
 // returns true on success or false for a parsing error
-BASE_EXPORT bool ParseProcVmstat(const std::string& input,
+// Exposed for testing.
+BASE_EXPORT bool ParseProcVmstat(StringPiece input,
                                  SystemMemoryInfoKB* meminfo);
 
 // Data from /proc/diskstats about system-wide disk I/O.
 struct BASE_EXPORT SystemDiskInfo {
   SystemDiskInfo();
   SystemDiskInfo(const SystemDiskInfo& other);
 
   // Serializes the platform specific fields to value.
   std::unique_ptr<Value> ToValue() const;
 
   uint64_t reads;
   uint64_t reads_merged;
   uint64_t sectors_read;
   uint64_t read_time;
   uint64_t writes;
   uint64_t writes_merged;
   uint64_t sectors_written;
   uint64_t write_time;
   uint64_t io;
   uint64_t io_time;
   uint64_t weighted_io_time;
 };
 
 // Checks whether the candidate string is a valid disk name, [hsv]d[a-z]+
 // for a generic disk or mmcblk[0-9]+ for the MMC case.
 // Names of disk partitions (e.g. sda1) are not valid.
-BASE_EXPORT bool IsValidDiskName(const std::string& candidate);
+BASE_EXPORT bool IsValidDiskName(StringPiece candidate);
 
 // Retrieves data from /proc/diskstats about system-wide disk I/O.
 // Fills in the provided |diskinfo| structure. Returns true on success.
 BASE_EXPORT bool GetSystemDiskInfo(SystemDiskInfo* diskinfo);
 
 // Returns the amount of time spent in user space since boot across all CPUs.
 BASE_EXPORT TimeDelta GetUserCpuTimeSinceBoot();
 #endif  // defined(OS_LINUX) || defined(OS_ANDROID)
 
 #if defined(OS_CHROMEOS)
@@ skipping 79 matching lines @@
 // |size| and |info| are output parameters, only valid on Success.
 BASE_EXPORT MachVMRegionResult GetBasicInfo(mach_port_t task,
                                             mach_vm_size_t* size,
                                             mach_vm_address_t* address,
                                             vm_region_basic_info_64* info);
 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 
 }  // namespace base
 
 #endif  // BASE_PROCESS_PROCESS_METRICS_H_