src/basic/cpu-set-util.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2010-2015 Lennart Poettering
   6   Copyright 2015 Filipe Brandenburger
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <errno.h>
  23 #include <stddef.h>
  24 #include <syslog.h>
  25
  26 #include "alloc-util.h"
  27 #include "cpu-set-util.h"
  28 #include "extract-word.h"
  29 #include "log.h"
  30 #include "macro.h"
  31 #include "parse-util.h"
  32 #include "string-util.h"
  33
  34 cpu_set_t* cpu_set_malloc(unsigned *ncpus) {
  35         cpu_set_t *c;
  36         unsigned n = 1024;
  37
  38         /* Allocates the cpuset in the right size */
  39
  40         for (;;) {
  41                 c = CPU_ALLOC(n);
  42                 if (!c)
  43                         return NULL;
  44
  45                 if (sched_getaffinity(0, CPU_ALLOC_SIZE(n), c) >= 0) {
  46                         CPU_ZERO_S(CPU_ALLOC_SIZE(n), c);
  47
  48                         if (ncpus)
  49                                 *ncpus = n;
  50
  51                         return c;
  52                 }
  53
  54                 CPU_FREE(c);
  55
  56                 if (errno != EINVAL)
  57                         return NULL;
  58
  59                 n *= 2;
  60         }
  61 }
  62
  63 int parse_cpu_set_and_warn(
  64                 const char *rvalue,
  65                 cpu_set_t **cpu_set,
  66                 const char *unit,
  67                 const char *filename,
  68                 unsigned line,
  69                 const char *lvalue) {
  70
  71         const char *whole_rvalue = rvalue;
  72         _cleanup_cpu_free_ cpu_set_t *c = NULL;
  73         unsigned ncpus = 0;
  74
  75         assert(lvalue);
  76         assert(rvalue);
  77
  78         for (;;) {
  79                 _cleanup_free_ char *word = NULL;
  80                 unsigned cpu, cpu_lower, cpu_upper;
  81                 int r;
  82
  83                 r = extract_first_word(&rvalue, &word, WHITESPACE ",", EXTRACT_QUOTES);
  84                 if (r < 0)
  85                         return log_syntax(unit, LOG_ERR, filename, line, r, "Invalid value for %s: %s", lvalue, whole_rvalue);
  86                 if (r == 0)
  87                         break;
  88
  89                 if (!c) {
  90                         c = cpu_set_malloc(&ncpus);
  91                         if (!c)
  92                                 return log_oom();
  93                 }
  94
  95                 r = parse_range(word, &cpu_lower, &cpu_upper);
  96                 if (r < 0)
  97                         return log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse CPU affinity '%s'", word);
  98                 if (cpu_lower >= ncpus || cpu_upper >= ncpus)
  99                         return log_syntax(unit, LOG_ERR, filename, line, EINVAL, "CPU out of range '%s' ncpus is %u", word, ncpus);
 100
 101                 if (cpu_lower > cpu_upper)
 102                         log_syntax(unit, LOG_WARNING, filename, line, 0, "Range '%s' is invalid, %u > %u", word, cpu_lower, cpu_upper);
 103                 else
 104                         for (cpu = cpu_lower; cpu <= cpu_upper; cpu++)
 105                                 CPU_SET_S(cpu, CPU_ALLOC_SIZE(ncpus), c);
 106         }
 107
 108         /* On success, sets *cpu_set and returns ncpus for the system. */
 109         if (c) {
 110                 *cpu_set = c;
 111                 c = NULL;
 112         }
 113
 114         return (int) ncpus;
 115 }
 116
 117 int parse_cpu_set(
 118                 const char *rvalue,
 119                 cpu_set_t **cpu_set) {
 120
 121         _cleanup_cpu_free_ cpu_set_t *c = NULL;
 122         unsigned ncpus = 0;
 123
 124         assert(rvalue);
 125
 126         for (;;) {
 127                 _cleanup_free_ char *word = NULL;
 128                 unsigned cpu, cpu_lower, cpu_upper;
 129                 int r;
 130
 131                 r = extract_first_word(&rvalue, &word, WHITESPACE ",", EXTRACT_QUOTES);
 132                 if (r == -ENOMEM)
 133                         return r;
 134                 if (r <= 0)
 135                         break;
 136
 137                 if (!c) {
 138                         c = cpu_set_malloc(&ncpus);
 139                         if (!c)
 140                                 return -ENOMEM;
 141                 }
 142
 143                 r = parse_range(word, &cpu_lower, &cpu_upper);
 144                 if (r < 0)
 145                         return r;
 146                 if (cpu_lower >= ncpus || cpu_upper >= ncpus)
 147                         return -EINVAL;
 148
 149                 if (cpu_lower <= cpu_upper)
 150                         for (cpu = cpu_lower; cpu <= cpu_upper; cpu++)
 151                                 CPU_SET_S(cpu, CPU_ALLOC_SIZE(ncpus), c);
 152         }
 153
 154         /* On success, sets *cpu_set and returns ncpus for the system. */
 155         if (c) {
 156                 *cpu_set = c;
 157                 c = NULL;
 158         }
 159
 160         return (int) ncpus;
 161 }