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Subject: Re: [PATCH 1/2] zram: Less checks in zram_bvec_write() after error
 detection
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
References: <566ABCD9.1060404@users.sourceforge.net>
 <566B13C1.50907@users.sourceforge.net>
 <566B14DA.1080709@users.sourceforge.net> <20151214002702.GA718@swordfish>
 <566E6895.5050603@users.sourceforge.net> <20151214100323.GA16372@swordfish>
Cc: LKML <linux-kernel@vger.kernel.org>, Minchan Kim <minchan@kernel.org>,
        Nitin Gupta <ngupta@vflare.org>, kernel-janitors@vger.kernel.org,
        Julia Lawall <julia.lawall@lip6.fr>,
        Andrew Morton <akpm@linux-foundation.org>
From: SF Markus Elfring <elfring@users.sourceforge.net>
Message-ID: <566ECC45.3050201@users.sourceforge.net>
Date: Mon, 14 Dec 2015 15:03:49 +0100
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>> I suggest to make the affected exception handling a bit more efficient.
>> Such source code fine-tuning has got a few special consequences.
> 
> by 'more efficient' you mean saving cpu cycles on 'bvec->bv_len != PAGE_SIZE'
> comparison in exception/error path?

Yes …


> ...
> check_strm:
> 	if (zstrm)
> 		zcomp_strm_release(zram->comp, zstrm);
> 	if (is_partial_io(bvec)) {
> free_uncmem:
> 		kfree(uncmem);
> 	}
> ...

I propose to jump over two sanity checks.


> no.

Thanks for your feedback.

Regards,
Markus