From 2b98ed888614d9633296a16a677107c556c4fa94 Mon Sep 17 00:00:00 2001 From: Lucas De Marchi Date: Fri, 3 Jun 2022 14:50:47 -0700 Subject: modprobe: Add --wait Retry module removal if it fails due to EAGAIN. This allows user to pass --wait , during which `modprobe -r` will keep trying to remove the module. Signed-off-by: Lucas De Marchi --- 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 @@ + + + + + + TIMEOUT_MSEC + + + + This option causes modprobe -r 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. + + + 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 #include +#include #include #include @@ -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 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; -- cgit v1.2.1