From da39ba5e1d65e997a98f6eb93ba6e6eb505f6e3c Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Tue, 22 Jul 2008 19:24:25 -0500 Subject: [PATCH] module: don't use stop_machine for waiting rmmod rmmod has a little-used "-w" option, meaning that instead of failing if the module is in use, it should block until the module becomes unused. In this case, we don't need to use stop_machine: Max Krasnyansky indicated that would be useful for SystemTap which loads/unloads new modules frequently. Cc: Max Krasnyansky Signed-off-by: Rusty Russell --- kernel/module.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index 5f80478b746d..705e1d5d516c 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -639,8 +639,8 @@ static int __try_stop_module(void *_sref) { struct stopref *sref = _sref; - /* If it's not unused, quit unless we are told to block. */ - if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) { + /* If it's not unused, quit unless we're forcing. */ + if (module_refcount(sref->mod) != 0) { if (!(*sref->forced = try_force_unload(sref->flags))) return -EWOULDBLOCK; } @@ -652,9 +652,16 @@ static int __try_stop_module(void *_sref) static int try_stop_module(struct module *mod, int flags, int *forced) { - struct stopref sref = { mod, flags, forced }; + if (flags & O_NONBLOCK) { + struct stopref sref = { mod, flags, forced }; - return stop_machine_run(__try_stop_module, &sref, NR_CPUS); + return stop_machine_run(__try_stop_module, &sref, NR_CPUS); + } else { + /* We don't need to stop the machine for this. */ + mod->state = MODULE_STATE_GOING; + synchronize_sched(); + return 0; + } } unsigned int module_refcount(struct module *mod) -- 2.20.1