LXR linux/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
  17enum 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
  97enum 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 */
 133static 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
 148int 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}
 185