linux-kernel - Re: [PATCH] [RFC] Add support for uevents on block device idle changes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <200911182310.31935.bzolnier@gmail.com>
Date:	Wed, 18 Nov 2009 23:10:31 +0100
From:	Bartlomiej Zolnierkiewicz <bzolnier@...il.com>
To:	Matthew Garrett <mjg@...hat.com>
Cc:	linux-kernel@...r.kernel.org, axboe@...nel.dk,
	linux-hotplug@...r.kernel.org
Subject: Re: [PATCH] [RFC] Add support for uevents on block device idle changes

On Tuesday 17 November 2009 15:37:39 Matthew Garrett wrote:

> @@ -1452,6 +1452,15 @@ static inline void __generic_make_request(struct bio *bio)
>  		if (should_fail_request(bio))
>  			goto end_io;
>  
> +		if (bio->bi_bdev->bd_disk->hysteresis_time &&
> +		    bio_has_data(bio) &&
> +		    !mod_timer(&bio->bi_bdev->bd_disk->hysteresis_timer,
> +			       jiffies+msecs_to_jiffies
> +			       (bio->bi_bdev->bd_disk->hysteresis_time))) {
> +			bio->bi_bdev->bd_disk->idle = 0;
> +			schedule_work(&bio->bi_bdev->bd_disk->idle_notify);
> +		}
> +

Wouldn't it be more reliable to hook into places where block requests are
issued/completed instead of queued?  This way you will not miss special
requests (some of them are quite common in practice and may take a relatively
long time to execute, i.e. FLUSH CACHE).

-- 
Bartlomiej Zolnierkiewicz
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/