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Date: Sat, 13 Jan 2024 01:31:08 -0800
From: Andi Kleen <ak@linux.intel.com>
To: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>,
	Oscar Salvador <osalvador@suse.de>, andrey.konovalov@linux.dev,
	Andrew Morton <akpm@linux-foundation.org>,
	Alexander Potapenko <glider@google.com>,
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	Evgenii Stepanov <eugenis@google.com>, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org,
	Andrey Konovalov <andreyknvl@google.com>
Subject: Re: [PATCH v4 12/22] lib/stackdepot: use read/write lock
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In-Reply-To: <CANpmjNOz7tBMK-HoyZNVR2KcgxEBY1Qym=DRa9gHLFkaNHLmVw@mail.gmail.com>

> This function is only refilling the freelist. Readers don't see it yet
> because it's in none of the hash table buckets. The freelist is only
> ever accessed under the lock.
> 
> Once an entry is allocated from the freelist, its size is overwritten
> with something non-zero (since it then contains a stack trace). Those
> updates are released into the right hash table bucket with
> list_add_rcu() (which implies a release).
> 
> Am I missing something else?

It's probably ok semantically here, but at least I would be consistent with
using the macro for a specific field.

-Andi