Re: [PATCH v2] kernel/params.c: defer most of param_sysfs_init() to late_initcall time

[Luis Chamberlain]

On Wed, Oct 26, 2022 at 12:13:56AM +0200, Rasmus Villemoes wrote:
> param_sysfs_init(), and in particular param_sysfs_builtin() is rather
> time-consuming; for my board, it currently takes about 30ms.
> 
> That amounts to about 3% of the time budget I have from U-Boot hands
> over control to linux and linux must assume responsibility for keeping
> the external watchdog happy.
> 
> We must still continue to initialize module_kset at subsys_initcall
> time, since otherwise any request_module() would fail in
> mod_sysfs_init(). However, the bulk of the work in
> param_sysfs_builtin(), namely populating /sys/module/*/version and/or
> /sys/module/*/parameters/ for builtin modules, can be deferred to
> late_initcall time - there's no userspace yet anyway to observe
> contents of /sys or the lack thereof.
> 
> Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>

Thanks, queued onto modules-next.

  Luis