Re: [PATCH v2] kernel/module: Reschedule while waiting for modules to finish loading

From: Prarit Bhargava
Date: Tue Apr 30 2019 - 18:20:31 EST




On 4/30/19 6:18 PM, Prarit Bhargava wrote:
> On a s390 z14 LAR with 2 cpus about stalls about 3% of the time while
> loading the s390_trng.ko module.
>
> Add a reschedule point to the loop that waits for modules to complete
> loading.
>

Sorry, sent in error.

P.

> v2: cleanup Fixes line.
>
> Reported-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
> Fixes: commit f9a75c1d717f ("modules: Only return -EEXIST for modules that have finished loading")
> Signed-off-by: Prarit Bhargava <prarit@xxxxxxxxxx>
> Cc: Jessica Yu <jeyu@xxxxxxxxxx>
> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
> ---
> kernel/module.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/kernel/module.c b/kernel/module.c
> index 410eeb7e4f1d..48748cfec991 100644
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@ -3585,6 +3585,7 @@ static int add_unformed_module(struct module *mod)
> finished_loading(mod->name));
> if (err)
> goto out_unlocked;
> + cond_resched();
> goto again;
> }
> err = -EEXIST;
>