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-types", 0 },
  46         { "lttng-probe-asoc", 0 },
  47         { "lttng-probe-block", 0 },
  48         { "lttng-probe-btrfs", 0 },
  49         { "lttng-probe-compaction", 0 },
  50         { "lttng-probe-ext3", 0 },
  51         { "lttng-probe-ext4", 0 },
  52         { "lttng-probe-gpio", 0 },
  53         { "lttng-probe-irq", 0 },
  54         { "lttng-probe-jbd", 0 },
  55         { "lttng-probe-jbd2", 0 },
  56         { "lttng-probe-kmem", 0 },
  57         { "lttng-probe-kvm", 0 },
  58         { "lttng-probe-kvm-x86", 0 },
  59         { "lttng-probe-kvm-x86-mmu", 0 },
  60         { "lttng-probe-lock", 0 },
  61         { "lttng-probe-module", 0 },
  62         { "lttng-probe-napi", 0 },
  63         { "lttng-probe-net", 0 },
  64         { "lttng-probe-power", 0 },
  65         { "lttng-probe-printk", 0 },
  66         { "lttng-probe-random", 0 },
  67         { "lttng-probe-rcu", 0 },
  68         { "lttng-probe-regmap", 0 },
  69         { "lttng-probe-regulator", 0 },
  70         { "lttng-probe-rpm", 0 },
  71         { "lttng-probe-sched", 0 },
  72         { "lttng-probe-scsi", 0 },
  73         { "lttng-probe-signal", 0 },
  74         { "lttng-probe-skb", 0 },
  75         { "lttng-probe-sock", 0 },
  76         { "lttng-probe-statedump", 0 },
  77         { "lttng-probe-sunrpc", 0 },
  78         { "lttng-probe-timer", 0 },
  79         { "lttng-probe-udp", 0 },
  80         { "lttng-probe-vmscan", 0 },
  81         { "lttng-probe-v4l2", 0 },
  82         { "lttng-probe-workqueue", 0 },
  83         { "lttng-probe-writeback", 0 },
  84 };
  85
  86 void modprobe_remove_lttng(const struct kern_modules_param *modules,
  87                            int entries)
  88 {
  89         int ret = 0, i;
  90         char modprobe[256];
  91
  92         for (i = entries - 1; i >= 0; i--) {
  93                 ret = snprintf(modprobe, sizeof(modprobe),
  94                                 "/sbin/modprobe -r -q %s",
  95                                 modules[i].name);
  96                 if (ret < 0) {
  97                         PERROR("snprintf modprobe -r");
  98                         goto error;
  99                 }
 100                 modprobe[sizeof(modprobe) - 1] = '\0';
 101                 ret = system(modprobe);
 102                 if (ret == -1) {
 103                         ERR("Unable to launch modprobe -r for module %s",
 104                                         kern_modules_control[i].name);
 105                 } else if (kern_modules_control[i].required
 106                                 && WEXITSTATUS(ret) != 0) {
 107                         ERR("Unable to remove module %s",
 108                                         kern_modules_control[i].name);
 109                 } else {
 110                         DBG("Modprobe removal successful %s",
 111                                         kern_modules_control[i].name);
 112                 }
 113         }
 114
 115 error:
 116         return;
 117
 118 }
 119
 120 /*
 121  * Remove control kernel module(s) in reverse load order.
 122  */
 123 void modprobe_remove_lttng_control(void)
 124 {
 125         return modprobe_remove_lttng(kern_modules_control,
 126                                      ARRAY_SIZE(kern_modules_control));
 127 }
 128
 129 /*
 130  * Remove data kernel modules in reverse load order.
 131  */
 132 void modprobe_remove_lttng_data(void)
 133 {
 134         return modprobe_remove_lttng(kern_modules_list,
 135                                      ARRAY_SIZE(kern_modules_list));
 136 }
 137
 138 /*
 139  * Remove all kernel modules in reverse order.
 140  */
 141 void modprobe_remove_lttng_all(void)
 142 {
 143         modprobe_remove_lttng_data();
 144         modprobe_remove_lttng_control();
 145 }
 146
 147 static int modprobe_lttng(const struct kern_modules_param *modules, int entries)
 148 {
 149         int ret = 0, i;
 150         char modprobe[256];
 151
 152         for (i = 0; i < entries; i++) {
 153                 ret = snprintf(modprobe, sizeof(modprobe),
 154                                 "/sbin/modprobe %s%s",
 155                                 modules[i].required ? "" : "-q ",
 156                                 modules[i].name);
 157                 if (ret < 0) {
 158                         PERROR("snprintf modprobe");
 159                         goto error;
 160                 }
 161                 modprobe[sizeof(modprobe) - 1] = '\0';
 162                 ret = system(modprobe);
 163                 if (ret == -1) {
 164                         ERR("Unable to launch modprobe for module %s",
 165                                         modules[i].name);
 166                 } else if (modules[i].required && WEXITSTATUS(ret) != 0) {
 167                         ERR("Unable to load module %s",
 168                                         modules[i].name);
 169                 } else {
 170                         DBG("Modprobe successfully %s",
 171                                         modules[i].name);
 172                 }
 173         }
 174
 175 error:
 176         return ret;
 177 }
 178
 179 /*
 180  * Load control kernel module(s).
 181  */
 182 int modprobe_lttng_control(void)
 183 {
 184         return modprobe_lttng(kern_modules_control,
 185                               ARRAY_SIZE(kern_modules_control));
 186 }
 187 /*
 188  * Load data kernel module(s).
 189  */
 190 int modprobe_lttng_data(void)
 191 {
 192         return modprobe_lttng(kern_modules_list,
 193                               ARRAY_SIZE(kern_modules_list));
 194 }