From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4A0B0E18.9090606@domain.hid> Date: Wed, 13 May 2009 20:14:48 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <4A0AC1C8.4050006@domain.hid> <4A0AC3F9.9090103@domain.hid> <4A0AC8A6.1000701@domain.hid> <1242220962.26544.955.camel@domain.hid> <4A0AE726.5090107@domain.hid> In-Reply-To: <4A0AE726.5090107@domain.hid> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-core] [PATCH] Fix host IRQ propagation List-Id: Xenomai life and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: xenomai-core Jan Kiszka wrote: > Philippe Gerum wrote: >> On Wed, 2009-05-13 at 15:18 +0200, Jan Kiszka wrote: >>> Gilles Chanteperdrix wrote: >>>> Jan Kiszka wrote: >>>>> Hi Gilles, >>>>> >>>>> I'm currently facing a nasty effect with switchtest over latest git head >>>>> (only tested this so far): running it inside my test VM (ie. with >>>>> frequent excessive latencies) I get a stalled Linux timer IRQ quite >>>>> quickly. System is otherwise still responsive, Xenomai timers are still >>>>> being delivered, other Linux IRQs too. switchtest complained about >>>>> >>>>> "Warning: Linux is compiled to use FPU in kernel-space." >>>>> >>>>> when it was started. Kernels are 2.6.28.9/ipipe-x86-2.2-07 and >>>>> 2.6.29.3/ipipe-x86-2.3-01 (LTTng patched in, but unused), both show the >>>>> same effect. >>>>> >>>>> Seen this before? >>>> The warning about Linux being compiled to use FPU in kernel-space means >>>> that you enabled soft RAID or compiled for K7, Geode, or any other >>> RAID is on (ordinary server config). >>> >>>> configuration using 3DNow for such simple operations as memcpy. It is >>>> harmless, it simply means that switchtest can not use fpu in kernel-space. >>>> >>>> The bug you have is probably the same as the one described here, which I >>>> am able to reproduce on my atom: >>>> https://mail.gna.org/public/xenomai-help/2009-04/msg00200.html >>>> >>>> Unfortunately, I for one am working on ARM issues and am not available >>>> to debug x86 issues. I think Philippe is busy too... >>> OK, looks like I got the same flu here. >>> >>> Philippe, did you find out any more details in the meantime? Then I'm >>> afraid I have to pick this up. >> No, I did not resume this task yet. Working from the powerpc side of the >> universe here. > > Hoho, don't think this rain here over x86 would have never made it down > to ARM or PPC land! ;) > > Martin, could you check if this helps you, too? > > Jan > > (as usual, ready to be pulled from 'for-upstream') > > ---------> > > Host IRQs may not only be triggered from non-root domains. But > rthal_propagate_irq's implemenation in I-pipe assumes so, which broke > host tick propagation under certain load scenarios. Besides that, > rthal_schedule_irq_root is the more efficient service for this purpose > anyway. > > Signed-off-by: Jan Kiszka > --- > > include/asm-generic/hal.h | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/include/asm-generic/hal.h b/include/asm-generic/hal.h > index b37e476..8137856 100644 > --- a/include/asm-generic/hal.h > +++ b/include/asm-generic/hal.h > @@ -437,7 +437,7 @@ int rthal_irq_host_release(unsigned irq, > > static inline void rthal_irq_host_pend(unsigned irq) > { > - rthal_propagate_irq(irq); > + rthal_schedule_irq_root(irq); > } > > int rthal_apc_alloc(const char *name, > Well, I would assume this could fix head, with the newly delayed root tick irq propagation. But the user reports this bug with 2.4 too... -- Gilles.