From: Takashi Iwai <tiwai@suse.de>
To: "Matt Fleming" <mjf@gentoo.org>
Cc: "Will Newton" <will.newton@gmail.com>,
linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@elte.hu,
venkatesh.pallipadi@intel.com
Subject: Re: [PATCH 2/3] HPET: Enter hpet_interrupt_handler with interrupts disabled
Date: Mon, 10 Nov 2008 17:53:58 +0100 [thread overview]
Message-ID: <s5htzafr07t.wl%tiwai@suse.de> (raw)
In-Reply-To: <5ff4a1e50811021423l795dd059v3d1667fb4bc9539c@mail.gmail.com>
At Sun, 2 Nov 2008 22:23:13 +0000,
Matt Fleming wrote:
>
> 2008/11/2 Will Newton <will.newton@gmail.com>:
> >
> > Combining IRQF_DISABLED and IRQF_SHARED does not reliably disable
> > interrupts in the handler. Perhaps IRQF_SHARED should be removed at
> > the same time?
> >
>
> I didn't know that. Under what conditions is it unreliable?
The kernel checks IRQF_DISABLED bit of only the first handler
even if multiple handlers are assigned to a single IRQ line.
Thus, if another handler without IRQF_DISABLED has been already
registered before yours, your IRQF_DISABLED is ignored.
See kernel/irq/handle.c.
Takashi
prev parent reply other threads:[~2008-11-10 16:54 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-02 16:04 [PATCH 1/3] HPET: Convert WARN_ON to WARN_ON_ONCE Matt Fleming
2008-11-02 16:04 ` [PATCH 2/3] HPET: Enter hpet_interrupt_handler with interrupts disabled Matt Fleming
2008-11-02 16:04 ` [PATCH 3/3] HPET: Read from HPET_Tn_CMP() not HPET_T0_CMP Matt Fleming
2008-11-09 10:33 ` Matt Fleming
2008-11-10 16:40 ` Thomas Gleixner
2008-11-02 21:35 ` [PATCH 2/3] HPET: Enter hpet_interrupt_handler with interrupts disabled Will Newton
2008-11-02 22:23 ` Matt Fleming
2008-11-10 16:53 ` Takashi Iwai [this message]
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=s5htzafr07t.wl%tiwai@suse.de \
--to=tiwai@suse.de \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=mjf@gentoo.org \
--cc=tglx@linutronix.de \
--cc=venkatesh.pallipadi@intel.com \
--cc=will.newton@gmail.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
all inboxes | Powered by JetHome®