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From:   Aleksey Romanov <AVRomanov@sberdevices.ru>
To:     Sergey Senozhatsky <senozhatsky@chromium.org>,
        "minchan@kernel.org" <minchan@kernel.org>
CC:     "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
        "ngupta@vflare.org" <ngupta@vflare.org>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "axboe@chromium.org" <axboe@chromium.org>,
        kernel <kernel@sberdevices.ru>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "mnitenko@gmail.com" <mnitenko@gmail.com>,
        Dmitry Rokosov <DDRokosov@sberdevices.ru>
Subject: Re: [PATCH v5] zram: remove double compression logic
Thread-Topic: [PATCH v5] zram: remove double compression logic
Thread-Index: AQHYYGSpGpTThyrzfUuEhSUG0yum7a2m55QAgAAG+YA=
Date:   Tue, 9 Aug 2022 13:06:19 +0000
Message-ID: <20220809130543.4dnh5aa3kdxbmzje@cab-wsm-0029881.sigma.sbrf.ru>
References: <20220505094443.11728-1-avromanov@sberdevices.ru>
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Hi Sergey,

On Tue, Aug 09, 2022 at 09:41:22PM +0900, Sergey Senozhatsky wrote:
> On (22/05/05 12:44), Alexey Romanov wrote:
> > @@ -1975,7 +1954,6 @@ static int zram_add(void)
> >  	if (ZRAM_LOGICAL_BLOCK_SIZE =3D=3D PAGE_SIZE)
> >  		blk_queue_max_write_zeroes_sectors(zram->disk->queue, UINT_MAX);
> > =20
> > -	blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, zram->disk->queue);
>=20
> By the way, why did it remove QUEUE_FLAG_STABLE_WRITES bit?

Minchan asked me to add this change and this description:

"Since b09ab054b69b, zram has used QUEUE_FLAG_STABLE_WRITES to prevent
buffer change between 1st and 2nd memory allocations. Since we remove
second trial memory allocation logic, we could remove the STABLE_WRITES
flag because there is no change buffer to be modified under us"

This seems to be logical.

--=20
Thank you,
Alexey=