chrome/browser/process_info_snapshot.h

   1 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_PROCESS_INFO_SNAPSHOT_H_
   6 #define CHROME_BROWSER_PROCESS_INFO_SNAPSHOT_H_
   7
   8 #include <sys/types.h>
   9
  10 #include <map>
  11 #include <string>
  12 #include <vector>
  13
  14 #include "base/process_util.h"
  15
  16 // A class which captures process information at a given point in time when its
  17 // |Sample()| method is called. This information can then be probed by PID.
  18 // |Sample()| may take a while to complete, so if calling from the browser
  19 // process, only do so from the file thread.
  20 // TODO(viettrungluu): This is currently only implemented and used on Mac, so
  21 // things are very Mac-specific. If this is ever implemented for other
  22 // platforms, we should subclass and add opaqueness (probably |ProcInfoEntry|
  23 // should be considered opaque).
  24 class ProcessInfoSnapshot {
  25  public:
  26   ProcessInfoSnapshot();
  27   ~ProcessInfoSnapshot();
  28
  29   // Maximum size of lists of PIDs which this class will accept; used in
  30   // |Sample()| below.
  31   static const size_t kMaxPidListSize;
  32
  33   // Capture a snapshot of process memory information for the
  34   // given list of PIDs. Call only from the file thread.
  35   //   |pid_list| - list of |ProcessId|s on which to capture information; must
  36   //     have no more than |kMaxPidListSize| (above) entries,
  37   //   returns - |true| if okay, |false| on error.
  38   bool Sample(std::vector<base::ProcessId> pid_list);
  39
  40   // Reset all statistics (deallocating any memory allocated).
  41   void Reset();
  42
  43   // Our basic structure for storing information about a process (the names are
  44   // mostly self-explanatory). Note that |command| may not actually reflect the
  45   // actual executable name; never trust it absolutely, and only take it
  46   // half-seriously when it begins with '/'.
  47   struct ProcInfoEntry {
  48     base::ProcessId pid;
  49     base::ProcessId ppid;
  50     uid_t uid;
  51     uid_t euid;
  52     // Explicitly use uint64_t instead of size_t in case this code is running
  53     // in a 32 bit process and the target process is 64 bit.
  54     uint64_t rss;
  55     uint64_t rshrd;
  56     uint64_t rprvt;
  57     uint64_t vsize;
  58     std::string command;
  59
  60     ProcInfoEntry();
  61   };
  62
  63   // Get process information for a given PID.
  64   //   |pid| - self-explanatory.
  65   //   |proc_info| - place to put the process information.
  66   //   returns - |true| if okay, |false| on error (including PID not found).
  67   bool GetProcInfo(int pid,
  68                    ProcInfoEntry* proc_info) const;
  69
  70   // Fills a |CommittedKBytes| with both resident and paged memory usage, as per
  71   // its definition (or as close as we can manage). In the current (Mac)
  72   // implementation, we map:
  73   //                              vsize --> comm_priv,
  74   //                                  0 --> comm_mapped,
  75   //                                  0 --> comm_image;
  76   //   in about:memory: virtual:private  =  comm_priv,
  77   //                     virtual:mapped  =  comm_mapped.
  78   // TODO(viettrungluu): Doing such a mapping is kind of ugly.
  79   //   |pid| - self-explanatory.
  80   //   |usage| - pointer to |CommittedBytes| to fill; zero-ed on error.
  81   //   returns - |true| on success, |false| on error (including PID not found).
  82   bool GetCommittedKBytesOfPID(int pid,
  83                                base::CommittedKBytes* usage) const;
  84
  85   // Fills a |WorkingSetKBytes| containing resident private and shared memory,
  86   // as per its definition (or as close as we can manage). In the current (Mac)
  87   // implementation, we map:
  88   //                          rprvt --> ws_priv,
  89   //                            rss --> ws_shareable,
  90   //                          rshrd --> ws_shared;
  91   //   in about:memory: res:private  =  ws_priv + ws_shareable - ws_shared,
  92   //                     res:shared  =  ws_shared / num_procs,
  93   //                      res:total  =  res:private + res:shared.
  94   // TODO(viettrungluu): Doing such a mapping is kind of ugly.
  95   //   |pid| - self-explanatory.
  96   //   |ws_usage| - pointer to |WorkingSetKBytes| to fill; zero-ed on error.
  97   //   returns - |true| on success, |false| on error (including PID not found).
  98   bool GetWorkingSetKBytesOfPID(int pid,
  99                                 base::WorkingSetKBytes* ws_usage) const;
 100
 101   // TODO(viettrungluu): Maybe we should also have the following (again, for
 102   // "compatibility"):
 103   //    size_t GetWorkingSetSizeOfPID(int pid) const;
 104   //    size_t GetPeakWorkingSetSizeOfPID(int pid) const;
 105   //    size_t GetPrivateBytesOfPID(int pid) const;
 106
 107  private:
 108   // map from |int| (PID) to |ProcInfoEntry|
 109   std::map<int,ProcInfoEntry> proc_info_entries_;
 110 };
 111
 112 #endif  // CHROME_BROWSER_PROCESS_INFO_SNAPSHOT_H_