From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: [rfc patch] drivers/block/zram: Replace bit spinlocks with
 rtmutex for -rt
Date: Fri, 1 Apr 2016 12:42:21 +0200
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Cc: Minchan Kim <minchan@kernel.org>, Nitin Gupta <ngupta@vflare.org>,
	Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
	RT <linux-rt-users@vger.kernel.org>
To: Mike Galbraith <umgwanakikbuti@gmail.com>
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* Mike Galbraith | 2016-03-31 04:08:28 [+0200]:

>(fixed the missed bit spinlock whackage you pointed out)
thanks.

>drivers/block/zram: Replace bit spinlocks with rtmutex for -rt
>
>They're nondeterministic, and lead to ___might_sleep() splats in -rt.
>OTOH, they're a lot less wasteful than an rtmutex per page.
Applied.
Although I'm disapointed about Sergey's argument against the spinlock in
general due to a few bytes used by lockdep which can be disabled. Not to
mention the usefull debug facility lockdep provides if one decides to
use.

Sebastian