Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1606908

Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic

From Julia Cartwright <julia@ni.com>
Newsgroups linux.kernel
Subject Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic
Date 2017-03-22 19:50 +0100
Message-ID <tnTuy-6TD-29@gated-at.bofh.it> (permalink)
References <tnQdj-4rn-9@gated-at.bofh.it> <tnSoO-63J-25@gated-at.bofh.it> <tnSRP-6Ap-11@gated-at.bofh.it> <tnTkS-6PF-21@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


[Multipart message — attachments visible in raw view] - view raw

On Wed, Mar 22, 2017 at 01:30:12PM -0500, Grygorii Strashko wrote:
> 
> On 03/22/2017 01:01 PM, Steven Rostedt wrote:
> > On Wed, 22 Mar 2017 12:37:59 -0500
> > Julia Cartwright <julia@ni.com> wrote:
> > 
> > > Which kernel were you testing on, here?  From what I can tell, this
> > > should have been fixed with Thomas's commit:
> > > 
> > >    2a1d3ab8986d ("genirq: Handle force threading of irqs with primary
> > > and thread handler")
> > 
> > Thanks Julia for looking into this. I just looked at the code, and saw
> > that it does very little with the lock held, and was fine with the
> > conversion. But if that interrupt handler should be in a thread, we
> > should see if that's the issue first.
> 
> 
> It will not be threaded because there are IRQF_ONESHOT used.
> 
> 	ret = devm_request_threaded_irq(&pdev->dev, irq,
> 					sti_mbox_irq_handler,
> 					sti_mbox_thread_handler,
> 					IRQF_ONESHOT, mdev->name, mdev);

Indeed.  I had skipped over this important detail when I was skimming
through the code.

Thanks for clarifying!

Is IRQF_ONESHOT really necessary for this device?  The primary handler
invokes sti_mbox_disable_channel() on the interrupting channel, which I
would hope would acquiesce the pending interrupt at the device-level?

Also, as written there are num_inst reads of STI_IRQ_VAL_OFFSET in the
primary handler, which seems inefficient...(unless of course reading
incurs side effects, here).

   Julia

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH RT 1/1] remoteproc: Prevent schedule while atomic Lionel Debieve <lionel.debieve@st.com> - 2017-03-22 16:20 +0100
  Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Steven Rostedt <rostedt@goodmis.org> - 2017-03-22 17:10 +0100
    Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Lionel DEBIEVE <lionel.debieve@st.com> - 2017-03-22 18:20 +0100
  Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Julia Cartwright <julia@ni.com> - 2017-03-22 18:40 +0100
    Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Steven Rostedt <rostedt@goodmis.org> - 2017-03-22 19:10 +0100
      Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Grygorii Strashko <grygorii.strashko@ti.com> - 2017-03-22 19:40 +0100
        Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Julia Cartwright <julia@ni.com> - 2017-03-22 19:50 +0100
          Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Lionel DEBIEVE <lionel.debieve@st.com> - 2017-03-23 09:30 +0100
            Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Lee Jones <lee.jones@linaro.org> - 2017-03-23 11:30 +0100
              Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Julia Cartwright <julia@ni.com> - 2017-03-23 22:00 +0100
          Re: [PATCH RT 1/1] remoteproc: Prevent schedule while atomic Thomas Gleixner <tglx@linutronix.de> - 2017-03-24 09:40 +0100

csiph-web