linux-kernel - Re: [PATCH 0/6] v4 block refcount conversion patches

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]

Date:   Fri, 20 Oct 2017 10:43:03 +0200
From:   Johannes Thumshirn <jthumshirn@...e.de>
To:     Elena Reshetova <elena.reshetova@...el.com>
Cc:     axboe@...nel.dk, james.bottomley@...senpartnership.com,
        linux-kernel@...r.kernel.org, linux-block@...r.kernel.org,
        linux-scsi@...r.kernel.org, linux-btrfs@...r.kernel.org,
        peterz@...radead.org, gregkh@...uxfoundation.org,
        fujita.tomonori@....ntt.co.jp, mingo@...hat.com, clm@...com,
        jbacik@...com, dsterba@...e.com, keescook@...omium.org
Subject: Re: [PATCH 0/6] v4 block refcount conversion patches

Elena Reshetova <elena.reshetova@...el.com> writes:
> Elena Reshetova (6):
>   block: convert bio.__bi_cnt from atomic_t to refcount_t
>   block: convert blk_queue_tag.refcnt from atomic_t to refcount_t
>   block: convert blkcg_gq.refcnt from atomic_t to refcount_t
>   block: convert io_context.active_ref from atomic_t to refcount_t
>   block: convert bsg_device.ref_count from atomic_t to refcount_t
>   drivers, block: convert xen_blkif.refcnt from atomic_t to refcount_t

Hi Elena,

While the bsg ref_count is cheap, do you have any numbers how the other
conversions compare in performance (throughput and latency) vs atomics?

It should be quite easy to measure against a null_blk device.

Thanks a lot,
       Johannes

-- 
Johannes Thumshirn                                          Storage
jthumshirn@...e.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: Felix Imendörffer, Jane Smithard, Graham Norton
HRB 21284 (AG Nürnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850