src/bin/lttng-sessiond/modprobe.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <dgoulet@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License, version 2 only,
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <sys/wait.h>
  22
  23 #include <common/common.h>
  24
  25 #include "modprobe.h"
  26 #include "kern-modules.h"
  27
  28 /* MUST be loaded first */
  29 const struct kern_modules_param kern_modules_control[] = {
  30         { "lttng-tracer", 1 },
  31 };
  32
  33 /* LTTng kernel tracer modules list */
  34 const struct kern_modules_param kern_modules_list[] = {
  35         { "lttng-ftrace", 0 },
  36         { "lttng-kprobes", 0 },
  37         { "lttng-kretprobes", 0 },
  38         { "lttng-lib-ring-buffer", 1 },
  39         { "lttng-ring-buffer-client-discard", 1 },
  40         { "lttng-ring-buffer-client-overwrite", 1 },
  41         { "lttng-ring-buffer-metadata-client", 1 },
  42         { "lttng-ring-buffer-client-mmap-discard", 1 },
  43         { "lttng-ring-buffer-client-mmap-overwrite", 1 },
  44         { "lttng-ring-buffer-metadata-mmap-client", 1 },
  45         { "lttng-probe-lttng", 1 },
  46         { "lttng-types", 0 },
  47         { "lttng-probe-asoc", 0 },
  48         { "lttng-probe-block", 0 },
  49         { "lttng-probe-ext3", 0 },
  50         { "lttng-probe-gpio", 0 },
  51         { "lttng-probe-irq", 0 },
  52         { "lttng-probe-jbd", 0 },
  53         { "lttng-probe-jbd2", 0 },
  54         { "lttng-probe-kmem", 0 },
  55         { "lttng-probe-kvm", 0 },
  56         { "lttng-probe-lock", 0 },
  57         { "lttng-probe-modules", 0 },
  58         { "lttng-probe-napi", 0 },
  59         { "lttng-probe-net", 0 },
  60         { "lttng-probe-power", 0 },
  61         { "lttng-probe-regulator", 0 },
  62         { "lttng-probe-sched", 0 },
  63         { "lttng-probe-scsi", 0 },
  64         { "lttng-probe-signal", 0 },
  65         { "lttng-probe-skb", 0 },
  66         { "lttng-probe-sock", 0 },
  67         { "lttng-probe-statedump", 0 },
  68         { "lttng-probe-timer", 0 },
  69         { "lttng-probe-udp", 0 },
  70         { "lttng-probe-vmscan", 0 },
  71 };
  72
  73 /*
  74  * Remove control kernel module(s) in reverse load order.
  75  */
  76 void modprobe_remove_lttng_control(void)
  77 {
  78         int ret = 0, i;
  79         char modprobe[256];
  80
  81         for (i = ARRAY_SIZE(kern_modules_control) - 1; i >= 0; i--) {
  82                 ret = snprintf(modprobe, sizeof(modprobe),
  83                                 "/sbin/modprobe -r -q %s",
  84                                 kern_modules_control[i].name);
  85                 if (ret < 0) {
  86                         PERROR("snprintf modprobe -r");
  87                         goto error;
  88                 }
  89                 modprobe[sizeof(modprobe) - 1] = '\0';
  90                 ret = system(modprobe);
  91                 if (ret == -1) {
  92                         ERR("Unable to launch modprobe -r for module %s",
  93                                         kern_modules_control[i].name);
  94                 } else if (kern_modules_control[i].required
  95                                 && WEXITSTATUS(ret) != 0) {
  96                         ERR("Unable to remove module %s",
  97                                         kern_modules_control[i].name);
  98                 } else {
  99                         DBG("Modprobe removal successful %s",
 100                                         kern_modules_control[i].name);
 101                 }
 102         }
 103
 104 error:
 105         return;
 106 }
 107
 108 /*
 109  * Remove data kernel modules in reverse load order.
 110  */
 111 void modprobe_remove_lttng_data(void)
 112 {
 113         int ret = 0, i;
 114         char modprobe[256];
 115
 116         for (i = ARRAY_SIZE(kern_modules_list) - 1; i >= 0; i--) {
 117                 ret = snprintf(modprobe, sizeof(modprobe),
 118                                 "/sbin/modprobe -r -q %s",
 119                                 kern_modules_list[i].name);
 120                 if (ret < 0) {
 121                         PERROR("snprintf modprobe -r");
 122                         goto error;
 123                 }
 124                 modprobe[sizeof(modprobe) - 1] = '\0';
 125                 ret = system(modprobe);
 126                 if (ret == -1) {
 127                         ERR("Unable to launch modprobe -r for module %s",
 128                                         kern_modules_list[i].name);
 129                 } else if (kern_modules_list[i].required
 130                                 && WEXITSTATUS(ret) != 0) {
 131                         ERR("Unable to remove module %s",
 132                                         kern_modules_list[i].name);
 133                 } else {
 134                         DBG("Modprobe removal successful %s",
 135                                         kern_modules_list[i].name);
 136                 }
 137         }
 138
 139 error:
 140         return;
 141 }
 142
 143 /*
 144  * Remove all kernel modules in reverse order.
 145  */
 146 void modprobe_remove_lttng_all(void)
 147 {
 148         modprobe_remove_lttng_data();
 149         modprobe_remove_lttng_control();
 150 }
 151
 152 /*
 153  * Load control kernel module(s).
 154  */
 155 int modprobe_lttng_control(void)
 156 {
 157         int ret = 0, i;
 158         char modprobe[256];
 159
 160         for (i = 0; i < ARRAY_SIZE(kern_modules_control); i++) {
 161                 ret = snprintf(modprobe, sizeof(modprobe),
 162                                 "/sbin/modprobe %s%s",
 163                                 kern_modules_control[i].required ? "" : "-q ",
 164                                 kern_modules_control[i].name);
 165                 if (ret < 0) {
 166                         PERROR("snprintf modprobe");
 167                         goto error;
 168                 }
 169                 modprobe[sizeof(modprobe) - 1] = '\0';
 170                 ret = system(modprobe);
 171                 if (ret == -1) {
 172                         ERR("Unable to launch modprobe for module %s",
 173                                         kern_modules_control[i].name);
 174                 } else if (kern_modules_control[i].required
 175                                 && WEXITSTATUS(ret) != 0) {
 176                         ERR("Unable to load module %s",
 177                                         kern_modules_control[i].name);
 178                 } else {
 179                         DBG("Modprobe successfully %s",
 180                                         kern_modules_control[i].name);
 181                 }
 182         }
 183
 184 error:
 185         return ret;
 186 }
 187
 188 /*
 189  * Load data kernel module(s).
 190  */
 191 int modprobe_lttng_data(void)
 192 {
 193         int ret = 0, i;
 194         char modprobe[256];
 195
 196         for (i = 0; i < ARRAY_SIZE(kern_modules_list); i++) {
 197                 ret = snprintf(modprobe, sizeof(modprobe),
 198                                 "/sbin/modprobe %s%s",
 199                                 kern_modules_list[i].required ? "" : "-q ",
 200                                 kern_modules_list[i].name);
 201                 if (ret < 0) {
 202                         PERROR("snprintf modprobe");
 203                         goto error;
 204                 }
 205                 modprobe[sizeof(modprobe) - 1] = '\0';
 206                 ret = system(modprobe);
 207                 if (ret == -1) {
 208                         ERR("Unable to launch modprobe for module %s",
 209                                         kern_modules_list[i].name);
 210                 } else if (kern_modules_list[i].required
 211                                 && WEXITSTATUS(ret) != 0) {
 212                         ERR("Unable to load module %s",
 213                                         kern_modules_list[i].name);
 214                 } else {
 215                         DBG("Modprobe successfully %s",
 216                                         kern_modules_list[i].name);
 217                 }
 218         }
 219
 220 error:
 221         return ret;
 222 }
 223
 224 /*
 225  * Load all lttng kernel modules.
 226  */
 227 int modprobe_lttng_all(void)
 228 {
 229         int ret;
 230
 231         ret = modprobe_lttng_control();
 232         if (ret < 0) {
 233                 goto error;
 234         }
 235
 236         ret = modprobe_lttng_data();
 237         if (ret < 0) {
 238                 goto error;
 239         }
 240
 241 error:
 242         return ret;
 243 }