Re: [PATCH 6/6] kmod: use simplified rate limit printk

Dmitry Torokhov
2017-05-19T22:23:34Z

On Thu, May 18, 2017 at 08:24:44PM -0700, Luis R. Rodriguez wrote:
> Just use the simplified rate limit printk when the max modprobe
> limit is reached, while at it throw out a bone should the error
> be triggered.
>
> Reviewed-by: Petr Mladek <pmladek@suse.com>
> Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
> ---
> kernel/kmod.c | 10 ++--------
> 1 file changed, 2 insertions(+), 8 deletions(-)
>
> diff --git a/kernel/kmod.c b/kernel/kmod.c
> index 7ea11dbc7564..56cd2a16e7ac 100644
> --- a/kernel/kmod.c
> +++ b/kernel/kmod.c
> @@ -166,7 +166,6 @@ int __request_module(bool wait, const char *fmt, ...)
> va_list args;
> char module_name[MODULE_NAME_LEN];
> int ret;
> - static int kmod_loop_msg;
>
> /*
> * We don't allow synchronous module loading from async. Module
> @@ -191,13 +190,8 @@ int __request_module(bool wait, const char *fmt, ...)
>
> ret = kmod_umh_threads_get();
> if (ret) {
> - /* We may be blaming an innocent here, but unlikely */
> - if (kmod_loop_msg < 5) {
> - printk(KERN_ERR
> - "request_module: runaway loop modprobe %s\n",
> - module_name);
> - kmod_loop_msg++;
> - }
> + pr_err_ratelimited("%s: module \"%s\" reached limit (%u) of concurrent modprobe calls\n",
> + __func__, module_name, max_modprobes);

This is completely different behavior, isn't it? Instead of reporting
first 5 occurrences we now reporting every once in a while. Why is this
new behavior better?

--
Dmitry