From: Lee Revell <rlrevell@joe-job.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Softirq preemption
Date: Thu, 01 Dec 2005 14:08:50 -0500 [thread overview]
Message-ID: <1133464131.7898.30.camel@mindpipe> (raw)
[-- Attachment #1: Type: text/plain, Size: 653 bytes --]
Ingo,
Is there any chance that the softirq preemption feature from the -rt
kernel can be pushed upstream?
Currently I am testing 2.6.14-rt21 with PREEMPT_DESKTOP and hard/softirq
preemption disabled in order to simulate the behavior of 2.6.14
mainline. The network TX softirq is the longest non-preemptible code
path, it can run for 5-6ms. However I can see that the preempt_count
drops to zero on many occasions, which IIRC means that no locks are held
and we could easily preempt at that point.
Without softirq preemption I don't see how we have any chance of meeting
the 1ms goal for desktop responsiveness that was decided on at OLS 2004.
Lee
[-- Attachment #2: softirq-tx.trace.gz --]
[-- Type: application/x-gzip, Size: 36670 bytes --]
next reply other threads:[~2005-12-01 19:09 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-12-01 19:08 Lee Revell [this message]
2005-12-07 1:31 ` Softirq preemption Lee Revell
2005-12-07 9:02 ` Ingo Molnar
-- strict thread matches above, loose matches on Subject: below --
2009-09-16 19:27 SoftIRQ preemption Meha Mehta
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=1133464131.7898.30.camel@mindpipe \
--to=rlrevell@joe-job.com \
--cc=linux-kernel@vger.kernel.org \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.