From: "Xavier Wang" <xavierwang@ms19.url.com.tw>
To: "Jesper Skov" <jskov@redhat.com>
Cc: <ecos-discuss@sources.redhat.com>
Subject: Re: [ECOS] nested interrupts
Date: Thu, 18 Jan 2001 04:15:00 -0000 [thread overview]
Message-ID: <001e01c08147$c1e44e80$6f2314ac@realtek.com.tw> (raw)
In-Reply-To: <otitnd9qr0.fsf@thinktwice.zoftcorp.dk>
Thanks, Jesper.
> >>>>> "Xavier" == Xavier Wang <xavierwang@ms19.url.com.tw> writes:
>
> Xavier> I got confused about nested interrupts. In
> Xavier> http://sources.redhat.com/ecos/docs-latest/porting/hal-interrupts.html
> Xavier> it seems that interrupts are disabled in ISRs, but enabled in
> Xavier> DSRs.
>
> Xavier> But Hugo's description in the same page said that
> Xavier> higher priority interrupts are enabled before calling
> Xavier> ISR. Which is true for nested interrupts?
>
> Both are true, but depending on configuration. There is an option that
> allows nested interrupts - when disabled, the former is valid, when
> enabled, the latter is valid.
>
> Xavier> If it's the former, should I rewrite the 'hal_cpu_int_enable'
> Xavier> macro used in hal_interrupt_stack_call_pending_DSRs (in
> Xavier> vector.S) to enable only higher priority interrupts? If it's
>
> No. All interrupts are allowed when executing DSRs. DSRs are only
> executin when no interrupts are pending.
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?
Thanks.
next prev parent reply other threads:[~2001-01-18 4:15 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 [this message]
2001-01-18 5:00 ` Nick Garnett
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='001e01c08147$c1e44e80$6f2314ac@realtek.com.tw' \
--to=xavierwang@ms19.url.com.tw \
--cc=ecos-discuss@sources.redhat.com \
--cc=jskov@redhat.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).