From: Tejun Heo <tj@kernel.org>
To: Shaohua Li <shaohua.li@intel.com>
Cc: lkml <linux-kernel@vger.kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
cl@linux.com
Subject: Re: [PATCH 1/4]percpu_counter: make API return consistent value
Date: Wed, 13 Apr 2011 03:49:27 +0900 [thread overview]
Message-ID: <20110412184927.GB16342@mtj.dyndns.org> (raw)
In-Reply-To: <1302595437.3981.127.camel@sli10-conroe>
Hello,
First of all, please somehow link patches of the same series. Either
write a head message and make all the patches replies to it
(preferred) or chain reply the patches (only when the number of
patches is small).
On Tue, Apr 12, 2011 at 04:03:57PM +0800, Shaohua Li wrote:
> the percpu_counter_*_positive() API SMP and !SMP aren't consistent. From
> the API name, we should return a non-negative value for them.
> Also if count < 0, returns 0 instead of 1 for *read_positive().
Ummm, on UP, the counters cannot be positive. The _positive interface
is there to make it easier to cope with deviations introduced by
unsynchronized modifications by different CPUs. On UP, such
deviations don't happen at all so _positive interface is the same as
the counterpart without the postfix.
Thanks.
--
tejun
next prev parent reply other threads:[~2011-04-12 18:49 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-12 8:03 [PATCH 1/4]percpu_counter: make API return consistent value Shaohua Li
2011-04-12 18:49 ` Tejun Heo [this message]
2011-04-13 1:24 ` Shaohua Li
2011-04-13 3:08 ` Tejun Heo
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=20110412184927.GB16342@mtj.dyndns.org \
--to=tj@kernel.org \
--cc=akpm@linux-foundation.org \
--cc=cl@linux.com \
--cc=linux-kernel@vger.kernel.org \
--cc=shaohua.li@intel.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;
as well as URLs for NNTP newsgroup(s).