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Message-ID: <084d7ef4-15a8-1d4e-6b20-5a848102ac03@suse.cz>
Date:   Fri, 16 Sep 2022 23:02:17 +0200
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Subject: Re: [PATCH V2] mm: slub: fix flush_cpu_slab()/__free_slab()
 invocations in task context.
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To:     Maurizio Lombardi <mlombard@redhat.com>
Cc:     linux-mm@kvack.org, rientjes@google.com, penberg@kernel.org,
        iamjoonsoo.kim@lge.com, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, bigeasy@linutronix.de,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>
References: <20220912161140.34281-1-mlombard@redhat.com>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <20220912161140.34281-1-mlombard@redhat.com>
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On 9/12/22 18:11, Maurizio Lombardi wrote:
> @@ -2730,7 +2735,7 @@ static void flush_all_cpus_locked(struct kmem_cache *s)
>  		INIT_WORK(&sfw->work, flush_cpu_slab);
>  		sfw->skip = false;
>  		sfw->s = s;
> -		schedule_work_on(cpu, &sfw->work);
> +		queue_work_on(cpu, flushwq, &sfw->work);
>  	}
>  
>  	for_each_online_cpu(cpu) {
> @@ -4858,6 +4863,8 @@ void __init kmem_cache_init(void)
>  
>  void __init kmem_cache_init_late(void)
>  {
> +	flushwq = create_workqueue("slub_flushwq");
> +	BUG_ON(!flushwq);

Adding new BUG_ON is essentially prohibited these days, so please use WARN_ON().
Other than that deprecation issue, looks fine to me.

>  }
>  
>  struct kmem_cache *