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| author | Luis R. Rodriguez <mcgrof@suse.com> | 2015-03-30 16:20:05 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-05-20 00:25:24 -0700 |
| commit | f2411da746985e60d4d087f3a43e271c61785927 (patch) | |
| tree | 09b6c3b2abd4774f63e4a0d467e3c70daa52663e /kernel/module.c | |
| parent | 765230b5f084863183aa8adb3405ab3f32c0b16e (diff) | |
| download | lwn-f2411da746985e60d4d087f3a43e271c61785927.tar.gz lwn-f2411da746985e60d4d087f3a43e271c61785927.zip | |
driver-core: add driver module asynchronous probe support
Some init systems may wish to express the desire to have device drivers
run their probe() code asynchronously. This implements support for this
and allows userspace to request async probe as a preference through a
generic shared device driver module parameter, async_probe.
Implementation for async probe is supported through a module parameter
given that since synchronous probe has been prevalent for years some
userspace might exist which relies on the fact that the device driver
will probe synchronously and the assumption that devices it provides
will be immediately available after this.
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/module.c')
| -rw-r--r-- | kernel/module.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/kernel/module.c b/kernel/module.c index 24d1f31d02f2..ea941bc327d5 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3107,7 +3107,7 @@ static noinline int do_init_module(struct module *mod) * * http://thread.gmane.org/gmane.linux.kernel/1420814 */ - if (current->flags & PF_USED_ASYNC) + if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC)) async_synchronize_full(); mutex_lock(&module_mutex); @@ -3240,8 +3240,16 @@ out: static int unknown_module_param_cb(char *param, char *val, const char *modname, void *arg) { + struct module *mod = arg; + int ret; + + if (strcmp(param, "async_probe") == 0) { + mod->async_probe_requested = true; + return 0; + } + /* Check for magic 'dyndbg' arg */ - int ret = ddebug_dyndbg_module_param_cb(param, val, modname); + ret = ddebug_dyndbg_module_param_cb(param, val, modname); if (ret != 0) pr_warn("%s: unknown parameter '%s' ignored\n", modname, param); return 0; |