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Date:   Sat, 15 Apr 2023 03:51:54 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     SeongJae Park <sj@kernel.org>
Cc:     akpm@linux-foundation.org, vbabka@suse.cz, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] mm/slab: break up RCU readers on
 SLAB_TYPESAFE_BY_RCU example code
Message-ID: <ZDoRSlHiyIvAz+pR@casper.infradead.org>
References: <20230415003754.1852-1-sj@kernel.org>
 <20230415003754.1852-3-sj@kernel.org>
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On Sat, Apr 15, 2023 at 12:37:53AM +0000, SeongJae Park wrote:
>   *
> + * begin:
>   *  rcu_read_lock();
> - * again:
>   *  obj = lockless_lookup(key);
>   *  if (obj) {
>   *    if (!try_get_ref(obj)) // might fail for free objects
> - *      goto again;
> + *      goto begin;
>   *
>   *    if (obj->key != key) { // not the object we expected
>   *      put_ref(obj);
> + *      rcu_read_unlock();
>   *      goto again;

- *      goto again;
+ *      goto begin;