From: Andrew Morton <akpm@linux-foundation.org>
To: Ken Chen <kenchen@google.com>
Cc: Ingo Molnar <mingo@elte.hu>, Li Zefan <lizf@cn.fujitsu.com>,
Paul Menage <menage@google.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [patch] export percpu cpuacct cgroup stats
Date: Sat, 6 Dec 2008 23:27:14 -0800 [thread overview]
Message-ID: <20081206232714.4b34b2fc.akpm@linux-foundation.org> (raw)
In-Reply-To: <b040c32a0812051016q7912688dw2c663a77121a8f18@mail.gmail.com>
On Fri, 5 Dec 2008 10:16:30 -0800 Ken Chen <kenchen@google.com> wrote:
> +static int cpuacct_percpu_seq_read(struct cgroup *cgroup, struct cftype *cft,
> + struct seq_file *m)
> +{
> + struct cpuacct *ca = cgroup_ca(cgroup);
> + u64 percpu;
> + int i;
> +
> + for_each_possible_cpu(i) {
> + spin_lock_irq(&cpu_rq(i)->lock);
> + percpu = *percpu_ptr(ca->cpuusage, i);
> + spin_unlock_irq(&cpu_rq(i)->lock);
> + seq_printf(m, "%llu ", (unsigned long long) percpu);
> + }
> + seq_printf(m, "\n");
> + return 0;
> +}
The locking is only needed for 32-bit, I assume?
The iteration across all possible CPUs seems a bit lame - that code
looks pretty easy to convert to hotplug goodness.
(All of which pertains to existing code, not to this patch).
next prev parent reply other threads:[~2008-12-07 7:27 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-12-04 4:48 [patch] export percpu cpuacct cgroup stats Ken Chen
2008-12-04 5:34 ` Li Zefan
2008-12-04 9:24 ` Ingo Molnar
2008-12-04 23:02 ` Paul Menage
2008-12-05 7:44 ` Ken Chen
2008-12-05 7:54 ` Li Zefan
2008-12-05 8:30 ` Ken Chen
2008-12-05 8:35 ` Li Zefan
2008-12-05 13:52 ` Ingo Molnar
2008-12-05 18:16 ` Ken Chen
2008-12-07 7:27 ` Andrew Morton [this message]
2008-12-08 14:33 ` Ingo Molnar
2008-12-05 18:10 ` Ken Chen
2008-12-08 1:25 ` Li Zefan
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=20081206232714.4b34b2fc.akpm@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=kenchen@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=lizf@cn.fujitsu.com \
--cc=menage@google.com \
--cc=mingo@elte.hu \
/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