Retry module removal if it fails due to EAGAIN. This allows user to pass
--wait <timeout>, during which `modprobe -r` will keep trying to remove
the module.
Signed-off-by: Lucas De Marchi <lucas.de.marchi@xxxxxxxxx>
---
man/modprobe.xml | 17 ++++++++++++
tools/modprobe.c | 70 +++++++++++++++++++++++++++++++++++++++++-------
2 files changed, 78 insertions(+), 9 deletions(-)
diff --git a/man/modprobe.xml b/man/modprobe.xml
index 0372b6b..db39c7a 100644
--- a/man/modprobe.xml
+++ b/man/modprobe.xml
@@ -388,6 +388,23 @@
</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term>
+ <option>-w</option>
+ </term>
+ <term>
+ <option>--wait=</option>TIMEOUT_MSEC
+ </term>
+ <listitem>
+ <para>
+ This option causes <command>modprobe -r</command> to continue trying to
+ remove a module if it fails due to the module being busy, i.e. its refcount
+ is not 0 at the time the call is made. Modprobe tries to remove the module
+ with an incremental sleep time between each tentative up until the maximum
+ wait time in milliseconds passed in this option.
+ </para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term>
<option>-S</option>
diff --git a/tools/modprobe.c b/tools/modprobe.c
index caaf87f..2a2ae21 100644
--- a/tools/modprobe.c
+++ b/tools/modprobe.c
@@ -32,6 +32,7 @@
#include <sys/wait.h>
#include <shared/array.h>
+#include <shared/util.h>
#include <shared/macro.h>
#include <libkmod/libkmod.h>
@@ -55,14 +56,18 @@ static int force = 0;
static int strip_modversion = 0;
static int strip_vermagic = 0;
static int remove_holders = 0;
+static unsigned long long wait_msec = 0;
static int quiet_inuse = 0;
-static const char cmdopts_s[] = "arRibfDcnC:d:S:sqvVh";
+static const char cmdopts_s[] = "arw:RibfDcnC:d:S:sqvVh";
static const struct option cmdopts[] = {
{"all", no_argument, 0, 'a'},
+
{"remove", no_argument, 0, 'r'},
{"remove-dependencies", no_argument, 0, 5},
{"remove-holders", no_argument, 0, 5},
+ {"wait", required_argument, 0, 'w'},
+
{"resolve-alias", no_argument, 0, 'R'},
{"first-time", no_argument, 0, 3},
{"ignore-install", no_argument, 0, 'i'},
@@ -110,6 +115,9 @@ static void help(void)
"\t-r, --remove Remove modules instead of inserting\n"
"\t --remove-dependencies Deprecated: use --remove-holders\n"
"\t --remove-holders Also remove module holders (use together with -r)\n"
+ "\t-w, --wait <MSEC> When removing a module, wait up to MSEC for\n"
+ "\t module's refcount to become 0 so it can be\n"
+ "\t removed (use together with -r)\n"
"\t --first-time Fail if module already inserted or removed\n"
"\t-i, --ignore-install Ignore install commands\n"
"\t-i, --ignore-remove Ignore remove commands\n"
@@ -322,6 +330,8 @@ end:
static int rmmod_do_remove_module(struct kmod_module *mod)
{
const char *modname = kmod_module_get_name(mod);
+ unsigned long long interval_msec = 0, t0_msec = 0,
+ tend_msec = 0;
int flags = 0, err;
SHOW("rmmod %s\n", modname);
@@ -332,13 +342,45 @@ static int rmmod_do_remove_module(struct kmod_module *mod)
if (force)
flags |= KMOD_REMOVE_FORCE;
- err = kmod_module_remove_module(mod, flags);
- if (err == -EEXIST) {
- if (!first_time)
- err = 0;
- else
- LOG("Module %s is not in kernel.\n", modname);
- }
+ if (wait_msec)
+ flags |= KMOD_REMOVE_NOLOG;
+
+ do {
+ err = kmod_module_remove_module(mod, flags);
+ if (err == -EEXIST) {
+ if (!first_time)
+ err = 0;
+ else
+ LOG("Module %s is not in kernel.\n", modname);
+ break;
+ } else if (err == -EAGAIN && wait_msec) {
+ unsigned long long until_msec;
+
+ if (!t0_msec) {
+ t0_msec = now_msec();
+ tend_msec = t0_msec + wait_msec;
+ interval_msec = 1;
+ }
+
+ until_msec = get_backoff_delta_msec(t0_msec, tend_msec,
+ &interval_msec);
+ err = sleep_until_msec(until_msec);
+
+ if (!t0_msec)
+ err = -ENOTSUP;
+
+ if (err < 0) {
+ ERR("Failed to sleep: %s\n", strerror(-err));
+ err = -EAGAIN;
+ break;
+ }
+ } else {
+ break;
+ }
+ } while (interval_msec);
+
+ if (err < 0 && wait_msec)
+ ERR("could not remove '%s': %s\n", modname, strerror(-err));
return err;
}
@@ -418,7 +460,7 @@ static int rmmod_do_module(struct kmod_module *mod, int flags)
}
/* 3. @mod itself, but check for refcnt first */
- if (!cmd && !ignore_loaded) {
+ if (!cmd && !ignore_loaded && !wait_msec) {
int usage = kmod_module_get_refcnt(mod);
if (usage > 0) {
@@ -800,6 +842,16 @@ static int do_modprobe(int argc, char **orig_argv)
case 5:
remove_holders = 1;
break;
+ case 'w': {
+ char *endptr = NULL;
+ wait_msec = strtoul(optarg, &endptr, 0);
+ if (!*optarg || *endptr) {
+ ERR("unexpected wait value '%s'.\n", optarg);
+ err = -1;
+ goto done;
+ }
+ break;
+ }
case 3:
first_time = 1;
break;
--
2.36.1
