From: Nick Garnett <nickg@cygnus.co.uk>
To: ecos-discuss@sourceware.cygnus.com
Subject: Re: [ECOS] nested interrupts
Date: Thu, 18 Jan 2001 05:00:00 -0000 [thread overview]
Message-ID: <wwgvgrd58np.fsf@balti.cambridge.redhat.com> (raw)
In-Reply-To: <001e01c08147$c1e44e80$6f2314ac@realtek.com.tw>
"Xavier Wang" <xavierwang@ms19.url.com.tw> writes:
> If there are some pending DSRs, it seems that these DSRs are executed
> in reverse order of interrupts/ISRs rather than in priority order. Does it
> cause more unpredictability for a real-time system? Can DSRs be
> prioritized? Is there a way to work around this?
>
DSRs are unprioritized. The priority supplied when creating an
interruopt is intended to prioritize the ISR in the hardware if that
is possible, or select its place in the chain when chained interrupts
are enabled.
There would be no advantage in prioritizing DSRs. All pending DSRs are
always run whenever any DSR can be run, and all DSRs are higher
priority than any threads and lower priority than any interrupts. The
order they get run in at this point is irrelevant, since the system
will not proceed until all of them have finished. Prioritized
execution should happen in threads, that's what they are there for.
--
Nick Garnett, eCos Kernel Architect
Red Hat, Cambridge, UK
next prev parent reply other threads:[~2001-01-18 5:00 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-01-17 23:51 Xavier Wang
2001-01-18 1:03 ` Jesper Skov
2001-01-18 4:15 ` Xavier Wang
2001-01-18 5:00 ` Nick Garnett [this message]
2001-01-18 4:59 ` Xavier Wang
2001-01-18 5:46 ` Nick Garnett
2001-01-18 21:52 ` Xavier Wang
2001-01-18 22:35 ` Jonathan Larmour
2001-01-18 8:26 ` Sergei Slobodov
2001-01-18 20:56 ` Xavier Wang
2001-01-18 22:37 ` Jonathan Larmour
-- strict thread matches above, loose matches on Subject: below --
2000-09-11 0:03 [ECOS] Nested Interrupts Sandeep Rikhi
2000-09-11 7:53 ` Jonathan Larmour
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=wwgvgrd58np.fsf@balti.cambridge.redhat.com \
--to=nickg@cygnus.co.uk \
--cc=ecos-discuss@sourceware.cygnus.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 read-only IMAP folder(s) and NNTP newsgroup(s).