tools/perf/util/target.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Helper functions for handling target threads/cpus
   4  *
   5  * Copyright (C) 2012, LG Electronics, Namhyung Kim <namhyung.kim@lge.com>
   6  */
   7
   8 #include "target.h"
   9
  10 #include <pwd.h>
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <linux/kernel.h>
  15 #include <linux/string.h>
  16
  17 enum target_errno target__validate(struct target *target)
  18 {
  19         enum target_errno ret = TARGET_ERRNO__SUCCESS;
  20
  21         if (target->pid)
  22                 target->tid = target->pid;
  23
  24         /* CPU and PID are mutually exclusive */
  25         if (target->tid && target->cpu_list) {
  26                 target->cpu_list = NULL;
  27                 if (ret == TARGET_ERRNO__SUCCESS)
  28                         ret = TARGET_ERRNO__PID_OVERRIDE_CPU;
  29         }
  30
  31         /* UID and PID are mutually exclusive */
  32         if (target->tid && target->uid_str) {
  33                 target->uid_str = NULL;
  34                 if (ret == TARGET_ERRNO__SUCCESS)
  35                         ret = TARGET_ERRNO__PID_OVERRIDE_UID;
  36         }
  37
  38         /* UID and CPU are mutually exclusive */
  39         if (target->uid_str && target->cpu_list) {
  40                 target->cpu_list = NULL;
  41                 if (ret == TARGET_ERRNO__SUCCESS)
  42                         ret = TARGET_ERRNO__UID_OVERRIDE_CPU;
  43         }
  44
  45         /* PID and SYSTEM are mutually exclusive */
  46         if (target->tid && target->system_wide) {
  47                 target->system_wide = false;
  48                 if (ret == TARGET_ERRNO__SUCCESS)
  49                         ret = TARGET_ERRNO__PID_OVERRIDE_SYSTEM;
  50         }
  51
  52         /* UID and SYSTEM are mutually exclusive */
  53         if (target->uid_str && target->system_wide) {
  54                 target->system_wide = false;
  55                 if (ret == TARGET_ERRNO__SUCCESS)
  56                         ret = TARGET_ERRNO__UID_OVERRIDE_SYSTEM;
  57         }
  58
  59         /* BPF and CPU are mutually exclusive */
  60         if (target->bpf_str && target->cpu_list) {
  61                 target->cpu_list = NULL;
  62                 if (ret == TARGET_ERRNO__SUCCESS)
  63                         ret = TARGET_ERRNO__BPF_OVERRIDE_CPU;
  64         }
  65
  66         /* BPF and PID/TID are mutually exclusive */
  67         if (target->bpf_str && target->tid) {
  68                 target->tid = NULL;
  69                 if (ret == TARGET_ERRNO__SUCCESS)
  70                         ret = TARGET_ERRNO__BPF_OVERRIDE_PID;
  71         }
  72
  73         /* BPF and UID are mutually exclusive */
  74         if (target->bpf_str && target->uid_str) {
  75                 target->uid_str = NULL;
  76                 if (ret == TARGET_ERRNO__SUCCESS)
  77                         ret = TARGET_ERRNO__BPF_OVERRIDE_UID;
  78         }
  79
  80         /* BPF and THREADS are mutually exclusive */
  81         if (target->bpf_str && target->per_thread) {
  82                 target->per_thread = false;
  83                 if (ret == TARGET_ERRNO__SUCCESS)
  84                         ret = TARGET_ERRNO__BPF_OVERRIDE_THREAD;
  85         }
  86
  87         /* THREAD and SYSTEM/CPU are mutually exclusive */
  88         if (target->per_thread && (target->system_wide || target->cpu_list)) {
  89                 target->per_thread = false;
  90                 if (ret == TARGET_ERRNO__SUCCESS)
  91                         ret = TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD;
  92         }
  93
  94         return ret;
  95 }
  96
  97 enum target_errno target__parse_uid(struct target *target)
  98 {
  99         struct passwd pwd, *result;
 100         char buf[1024];
 101         const char *str = target->uid_str;
 102
 103         target->uid = UINT_MAX;
 104         if (str == NULL)
 105                 return TARGET_ERRNO__SUCCESS;
 106
 107         /* Try user name first */
 108         getpwnam_r(str, &pwd, buf, sizeof(buf), &result);
 109
 110         if (result == NULL) {
 111                 /*
 112                  * The user name not found. Maybe it's a UID number.
 113                  */
 114                 char *endptr;
 115                 int uid = strtol(str, &endptr, 10);
 116
 117                 if (*endptr != '\0')
 118                         return TARGET_ERRNO__INVALID_UID;
 119
 120                 getpwuid_r(uid, &pwd, buf, sizeof(buf), &result);
 121
 122                 if (result == NULL)
 123                         return TARGET_ERRNO__USER_NOT_FOUND;
 124         }
 125
 126         target->uid = result->pw_uid;
 127         return TARGET_ERRNO__SUCCESS;
 128 }
 129
 130 /*
 131  * This must have a same ordering as the enum target_errno.
 132  */
 133 static const char *target__error_str[] = {
 134         "PID/TID switch overriding CPU",
 135         "PID/TID switch overriding UID",
 136         "UID switch overriding CPU",
 137         "PID/TID switch overriding SYSTEM",
 138         "UID switch overriding SYSTEM",
 139         "SYSTEM/CPU switch overriding PER-THREAD",
 140         "BPF switch overriding CPU",
 141         "BPF switch overriding PID/TID",
 142         "BPF switch overriding UID",
 143         "BPF switch overriding THREAD",
 144         "Invalid User: %s",
 145         "Problems obtaining information for user %s",
 146 };
 147
 148 int target__strerror(struct target *target, int errnum,
 149                           char *buf, size_t buflen)
 150 {
 151         int idx;
 152         const char *msg;
 153
 154         BUG_ON(buflen == 0);
 155
 156         if (errnum >= 0) {
 157                 str_error_r(errnum, buf, buflen);
 158                 return 0;
 159         }
 160
 161         if (errnum <  __TARGET_ERRNO__START || errnum >= __TARGET_ERRNO__END)
 162                 return -1;
 163
 164         idx = errnum - __TARGET_ERRNO__START;
 165         msg = target__error_str[idx];
 166
 167         switch (errnum) {
 168         case TARGET_ERRNO__PID_OVERRIDE_CPU ...
 169              TARGET_ERRNO__BPF_OVERRIDE_THREAD:
 170                 snprintf(buf, buflen, "%s", msg);
 171                 break;
 172
 173         case TARGET_ERRNO__INVALID_UID:
 174         case TARGET_ERRNO__USER_NOT_FOUND:
 175                 snprintf(buf, buflen, msg, target->uid_str);
 176                 break;
 177
 178         default:
 179                 /* cannot reach here */
 180                 break;
 181         }
 182
 183         return 0;
 184 }