RE: [PATCH] 2.6.1-mm2: Get irq_vector size right for generic subarch UP installer kernels

[Nakajima, Jun]

assign_irq_vector() is okay, and it simply returns vectors
(FIRST_DEVICE_VECTOR <= vector < FIRST_SYSTEM_VECTOR). That means those
IRQs will eventually share the same vector(s). Look at the code.

Jun

> -----Original Message-----
> From: linux-kernel-owner@xxxxxxxxxxxxxxx [mailto:linux-kernel-
> owner@xxxxxxxxxxxxxxx] On Behalf Of Zwane Mwaikambo
> Sent: Tuesday, January 13, 2004 5:00 PM
> To: James Cleverdon
> Cc: Andrew Morton; linux-kernel@xxxxxxxxxxxxxxx; Linus Torvalds; Chris
> McDermott; Martin J. Bligh
> Subject: Re: [PATCH] 2.6.1-mm2: Get irq_vector size right for generic
> subarch UP installer kernels
> 
> On Tue, 13 Jan 2004, James Cleverdon wrote:
> 
> > Problem:  Earlier I didn't consider the case of the generic sub-arch
and
> > uni-proc installer kernels used by a number of distros.  It
currently is
> > scaled by NR_CPUS.  The correct values should be big for summit and
> generic,
> > and can stay the same for all others.
> 
> This all looks strange, especially in assign_irq_vector() does this
> mean that you'll try and allocate up to 1024 vectors?
> 
> > diff -pru 2.6.1-mm2/include/asm-i386/mach-default/irq_vectors.h
> > t1mm2/include/asm-i386/mach-default/irq_vectors.h
> > --- 2.6.1-mm2/include/asm-i386/mach-default/irq_vectors.h
2004-01-08
> > 22:59:19.000000000 -0800
> > +++ t1mm2/include/asm-i386/mach-default/irq_vectors.h
2004-01-13
> > 13:43:56.000000000 -0800
> > @@ -90,8 +90,12 @@
> >  #else
> >  #ifdef CONFIG_X86_IO_APIC
> >  #define NR_IRQS 224
> > -# if (224 >= 32 * NR_CPUS)
> > -# define NR_IRQ_VECTORS NR_IRQS
> > +/*
> > + * For Summit or generic (i.e. installer) kernels, we have lots of
I/O
> APICs,
> > + * even with uni-proc kernels, so use a big array.
> > + */
> > +# if defined(CONFIG_X86_SUMMIT) || defined(CONFIG_X86_GENERICARCH)
> > +# define NR_IRQ_VECTORS 1024
> >  # else
> >  # define NR_IRQ_VECTORS (32 * NR_CPUS)
> >  # endif
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/