resource/vtimes.c

   1 /* Copyright (C) 1991-2023 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <stddef.h>
  19 #include <sys/resource.h>
  20 #include <shlib-compat.h>
  21
  22 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_33)
  23
  24 /* Granularity of the `vm_utime' and `vm_stime' fields of a `struct vtimes'.
  25    (This is the frequency of the machine's power supply, in Hz.)  */
  26 # define VTIMES_UNITS_PER_SECOND 60
  27
  28 struct vtimes
  29 {
  30   /* User time used in units of 1/VTIMES_UNITS_PER_SECOND seconds.  */
  31   int vm_utime;
  32   /* System time used in units of 1/VTIMES_UNITS_PER_SECOND seconds.  */
  33   int vm_stime;
  34
  35   /* Amount of data and stack memory used (kilobyte-seconds).  */
  36   unsigned int vm_idsrss;
  37   /* Amount of text memory used (kilobyte-seconds).  */
  38   unsigned int vm_ixrss;
  39   /* Maximum resident set size (text, data, and stack) (kilobytes).  */
  40   int vm_maxrss;
  41
  42   /* Number of hard page faults (i.e. those that required I/O).  */
  43   int vm_majflt;
  44   /* Number of soft page faults (i.e. those serviced by reclaiming
  45      a page from the list of pages awaiting reallocation.  */
  46   int vm_minflt;
  47
  48   /* Number of times a process was swapped out of physical memory.  */
  49   int vm_nswap;
  50
  51   /* Number of input operations via the file system.  Note: This
  52      and `ru_oublock' do not include operations with the cache.  */
  53   int vm_inblk;
  54   /* Number of output operations via the file system.  */
  55   int vm_oublk;
  56 };
  57
  58 /* Return the number of 1/VTIMES_UNITS_PER_SECOND-second
  59    units in the `struct timeval' TV.  */
  60 # define TIMEVAL_TO_VTIMES(tv) \
  61   ((tv.tv_sec * VTIMES_UNITS_PER_SECOND) \
  62    + (tv.tv_usec * VTIMES_UNITS_PER_SECOND / 1000000))
  63
  64 /* If VT is not NULL, write statistics for WHO into *VT.
  65    Return 0 for success, -1 for failure.  */
  66 static int
  67 vtimes_one (struct vtimes *vt, enum __rusage_who who)
  68 {
  69   if (vt != NULL)
  70     {
  71       struct rusage usage;
  72
  73       if (__getrusage (who, &usage) < 0)
  74         return -1;
  75
  76       vt->vm_utime = TIMEVAL_TO_VTIMES (usage.ru_utime);
  77       vt->vm_stime = TIMEVAL_TO_VTIMES (usage.ru_stime);
  78       vt->vm_idsrss = usage.ru_idrss + usage.ru_isrss;
  79       vt->vm_majflt = usage.ru_majflt;
  80       vt->vm_minflt = usage.ru_minflt;
  81       vt->vm_nswap = usage.ru_nswap;
  82       vt->vm_inblk = usage.ru_inblock;
  83       vt->vm_oublk = usage.ru_oublock;
  84     }
  85   return 0;
  86 }
  87
  88 /* If CURRENT is not NULL, write statistics for the current process into
  89    *CURRENT.  If CHILD is not NULL, write statistics for all terminated child
  90    processes into *CHILD.  Returns 0 for success, -1 for failure.  */
  91 int
  92 __vtimes (struct vtimes *current, struct vtimes *child)
  93 {
  94   if (vtimes_one (current, RUSAGE_SELF) < 0
  95       || vtimes_one (child, RUSAGE_CHILDREN) < 0)
  96     return -1;
  97   return 0;
  98 }
  99 compat_symbol (libc, __vtimes, vtimes, GLIBC_2_0);
 100
 101 #endif /* SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_33)  */