From: Jens Axboe <axboe@suse.de>
To: Andrew Morton <akpm@digeo.com>
Cc: "David S. Miller" <davem@redhat.com>,
rusty@rustcorp.com.au, dipankar@in.ibm.com,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] kmalloc_percpu
Date: Tue, 6 May 2003 09:25:00 +0200 [thread overview]
Message-ID: <20030506072500.GS812@suse.de> (raw)
In-Reply-To: <20030505235758.25f769fc.akpm@digeo.com>
On Mon, May 05 2003, Andrew Morton wrote:
> "David S. Miller" <davem@redhat.com> wrote:
> >
> > From: Andrew Morton <akpm@digeo.com>
> > Date: Mon, 5 May 2003 23:42:48 -0700
> >
> > Can't think of anything very clever there, except to go and un-percpuify the
> > disk stats. I think that's best, really - disk requests only come in at 100
> > to 200 per second - atomic_t's or int-plus-per-disk-spinlock will be fine.
> >
> > Use some spinlock we already have to be holding during the
> > counter bumps.
>
> Last time we looked at that, q->lock was already held in almost all the right
> places so yes, that'd work.
As far as I can see, queue lock _is_ held in all the right spot. At
least where it matters, adding new samples.
> > Frankly, these things don't need to be %100 accurate. Using
> > a new spinlock or an atomic_t for this seems rediculious.
>
> The disk_stats structure has an "in flight" member. If we don't have proper
> locking around that, disks will appear to have -3 requests in flight for all
> time, which would look a tad odd.
So check for < 0 in flight? I totally agree with davem here.
--
Jens Axboe
next prev parent reply other threads:[~2003-05-06 7:12 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-05-05 8:08 [PATCH] kmalloc_percpu Rusty Russell
2003-05-05 8:47 ` Andrew Morton
2003-05-06 0:47 ` Rusty Russell
2003-05-06 1:52 ` Andrew Morton
2003-05-06 2:11 ` David S. Miller
2003-05-06 4:08 ` Rusty Russell
2003-05-06 3:40 ` David S. Miller
2003-05-06 5:02 ` Andrew Morton
2003-05-06 4:16 ` David S. Miller
2003-05-06 5:48 ` Andrew Morton
2003-05-06 5:35 ` David S. Miller
2003-05-06 6:55 ` Andrew Morton
2003-05-06 5:57 ` David S. Miller
2003-05-06 7:22 ` Andrew Morton
2003-05-06 6:15 ` David S. Miller
2003-05-06 7:34 ` Andrew Morton
2003-05-06 8:42 ` William Lee Irwin III
2003-05-06 14:38 ` Martin J. Bligh
2003-05-06 7:20 ` Dipankar Sarma
2003-05-06 8:28 ` Rusty Russell
2003-05-06 8:47 ` Andrew Morton
2003-05-07 1:57 ` Rusty Russell
2003-05-07 2:41 ` William Lee Irwin III
2003-05-07 4:03 ` Paul Mackerras
2003-05-07 4:22 ` William Lee Irwin III
2003-05-07 4:56 ` Paul Mackerras
2003-05-07 5:19 ` William Lee Irwin III
2003-05-07 4:10 ` Martin J. Bligh
2003-05-07 12:13 ` William Lee Irwin III
2003-05-07 4:15 ` Rusty Russell
2003-05-07 5:37 ` Andrew Morton
2003-05-08 0:53 ` Rusty Russell
2003-05-06 14:41 ` Martin J. Bligh
2003-05-06 6:42 ` Andrew Morton
2003-05-06 5:39 ` David S. Miller
2003-05-06 6:57 ` Andrew Morton
2003-05-06 7:25 ` Jens Axboe [this message]
2003-05-06 10:41 ` Ingo Oeser
2003-05-06 16:05 ` Bryan O'Sullivan
2003-05-06 8:06 ` Rusty Russell
2003-05-06 5:03 ` Dipankar Sarma
2003-05-06 4:28 ` Andrew Morton
2003-05-06 3:37 ` David S. Miller
2003-05-06 4:11 ` Rusty Russell
2003-05-06 5:07 ` Ravikiran G Thirumalai
2003-05-06 8:03 ` Rusty Russell
2003-05-06 9:23 ` David S. Miller
2003-05-06 9:34 ` Ravikiran G Thirumalai
2003-05-06 9:38 ` Dipankar Sarma
2003-05-07 2:14 ` Rusty Russell
2003-05-07 5:51 ` Ravikiran G Thirumalai
2003-05-07 6:16 ` Rusty Russell
2003-05-08 7:42 ` Ravikiran G Thirumalai
2003-05-08 7:47 ` Rusty Russell
-- strict thread matches above, loose matches on Subject: below --
2002-10-31 16:06 [patch] kmalloc_percpu Ravikiran G Thirumalai
2002-11-01 8:33 ` Rusty Russell
2002-11-05 16:00 ` Dipankar Sarma
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=20030506072500.GS812@suse.de \
--to=axboe@suse.de \
--cc=akpm@digeo.com \
--cc=davem@redhat.com \
--cc=dipankar@in.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=rusty@rustcorp.com.au \
/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).