Sender: Tejun Heo <htejun@gmail.com>
Date:   Fri, 3 Feb 2023 09:29:46 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Petr Mladek <pmladek@suse.com>
Cc:     Lai Jiangshan <jiangshanlai@gmail.com>,
        Michal Koutny <mkoutny@suse.com>, linux-kernel@vger.kernel.org
Subject: Re: [RFC 2/5] workqueue: Warn when a new worker could not be created
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On Fri, Feb 03, 2023 at 03:10:28PM +0100, Petr Mladek wrote:
> A solution would be to use a custom printk_ratelimited_wq() that would
> allow printing one message per 2 * wq_watchdog_thresh.
> Something like:
> 
> #define printk_ratelimited_wq(fmt, ...)					\
> ({									\
> 	static DEFINE_RATELIMIT_STATE(_rs, 60 * HZ, 1);			\
> 									\
> 	if (__ratelimit(&_rs))						\
> 		printk(fmt, ##__VA_ARGS__);				\
> })
> 
> I admit that it is much easier than __print_create_worker_failure().
> 
> The only problem might be that wq_watchdog_thresh might be modified
> at runtime. But it can be solved by sharing the same
> struct ratelimit_state rs in all printk_ratelimited_wq() calls
> and updating it together with wq_watchdog_thresh.
> 
> Would you prefer the custom printk_ratelimited_wq(), please?

Yeah, I think so.

Thanks.

-- 
tejun