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Subject: Re: [PATCH v2] Increase page and bit waitqueue hash size
To:     Nicholas Piggin <npiggin@gmail.com>, linux-kernel@vger.kernel.org
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-mm@kvack.org, Anton Blanchard <anton@ozlabs.org>,
        Ingo Molnar <mingo@kernel.org>
References: <20210317075427.587806-1-npiggin@gmail.com>
From:   Rasmus Villemoes <linux@rasmusvillemoes.dk>
Message-ID: <89cb49c0-2736-dd4c-f401-4b88c22cc11f@rasmusvillemoes.dk>
Date:   Wed, 17 Mar 2021 11:12:44 +0100
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On 17/03/2021 08.54, Nicholas Piggin wrote:

> +#if CONFIG_BASE_SMALL
> +static const unsigned int page_wait_table_bits = 4;
>  static wait_queue_head_t page_wait_table[PAGE_WAIT_TABLE_SIZE] __cacheline_aligned;

>  
> +	if (!CONFIG_BASE_SMALL) {
> +		page_wait_table = alloc_large_system_hash("page waitqueue hash",
> +							sizeof(wait_queue_head_t),
> +							0,

So, how does the compiler not scream at you for assigning to an array,
even if it's inside an if (0)?

Rasmus