From: Jens Axboe <axboe@fb.com>
To: Dan Qing Zhang <dqzhang@linux.vnet.ibm.com>
Cc: fio@vger.kernel.org, zhong@linux.vnet.ibm.com
Subject: Re: [FIO][PATCH v1] powerpc: fix cpus_online() to get correct max CPU number for powerpc64
Date: Mon, 25 Jan 2016 08:30:25 -0700 [thread overview]
Message-ID: <56A63F91.6090102@fb.com> (raw)
In-Reply-To: <1453727058-45619-1-git-send-email-dqzhang@linux.vnet.ibm.com>
On 01/25/2016 06:04 AM, Dan Qing Zhang wrote:
> This patch tries to fix cpus_online() for powerpc64 when running fio
> by using parameter "cpus_allowed", in order to obtain correct max CPU
> number on powerpc64 architecture.
>
> When changing SMT settings on powerpc architecture, the way of cpu
> numbering is changing as well. For example, when SMT=off, CPUs are
> numbered like 0,8,16,..., while when SMT=2, CPUs are numbered like
> 0,1,8,9,.... Therefore, sysconf(_SC_NPROCESSORS_ONLN) is not applied
> to get exact max CPU number on powerpc. And the max_cpu value can be
> correctly ontained by using sysconf(_SC_NPROCESSORS_CONF).
Thanks, applied. I have a general dislike for discontiguous CPU
numbering, be it in the kernel or in user space :-)
--
Jens Axboe
prev parent reply other threads:[~2016-01-25 15:30 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-25 13:04 [FIO][PATCH v1] powerpc: fix cpus_online() to get correct max CPU number for powerpc64 Dan Qing Zhang
2016-01-25 15:30 ` Jens Axboe [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=56A63F91.6090102@fb.com \
--to=axboe@fb.com \
--cc=dqzhang@linux.vnet.ibm.com \
--cc=fio@vger.kernel.org \
--cc=zhong@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox