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Date:   Sun, 20 Dec 2020 01:18:35 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Vitaly Wool <vitaly.wool@konsulko.com>
Cc:     Mike Galbraith <efault@gmx.de>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>,
        Barry Song <song.bao.hua@hisilicon.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Minchan Kim <minchan@kernel.org>,
        NitinGupta <ngupta@vflare.org>
Subject: Re: [PATCH] zsmalloc: do not use bit_spin_lock
Message-ID: <20201220011835.GU15600@casper.infradead.org>
References: <18669bd607ae9efbf4e00e36532c7aa167d0fa12.camel@gmx.de>
 <20201220002228.38697-1-vitaly.wool@konsulko.com>
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On Sun, Dec 20, 2020 at 02:22:28AM +0200, Vitaly Wool wrote:
> zsmalloc takes bit spinlock in its _map() callback and releases it
> only in unmap() which is unsafe and leads to zswap complaining
> about scheduling in atomic context.
> 
> To fix that and to improve RT properties of zsmalloc, remove that
> bit spinlock completely and use a bit flag instead.

Isn't this just "I open coded bit spinlock to make the lockdep
warnings go away"?