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Date: Tue, 27 Mar 2018 17:10:15 +0900
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Minchan Kim <minchan@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Greg KH <gregkh@linuxfoundation.org>
Subject: Re: [PATCH v2 4/4] zram: introduce zram memory tracking
Message-ID: <20180327081015.GA3307@jagdpanzerIV>
References: <20180327065033.181819-1-minchan@kernel.org>
 <20180327065033.181819-5-minchan@kernel.org>
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On (03/27/18 15:50), Minchan Kim wrote:
[..]
>
> +	char flags[__NR_ZRAM_PAGEFLAGS - ZRAM_FLAG_SHIFT];
>

Technically, you don't need this buffer...

> +		snprintf(flags, sizeof(flags), "%c%c%c",
> +			zram_test_flag(zram, index, ZRAM_SAME) ? 's' : '.',
> +			zram_test_flag(zram, index, ZRAM_WB) ? 'w' : '.',
> +			zram_test_flag(zram, index, ZRAM_HUGE) ? 'h' : '.');
> +
> +		last_access = get_seconds() - zram->table[index].ac_time;
> +		copied = snprintf(kbuf + written, count, "%12lu %6s %12lu\n",
> +						index, flags, last_access);

... if you'll do flags decoding in place. But if you prefer it this way
then OK.

	-ss