cvs commit: src/sys/amd64/amd64 io_apic.c local_apic.c src/sys/amd64/include apicvar.h intr_machdep.h src/sys/i386/i386 io_apic.c local_apic.c src/sys/i386/include apicvar.h intr_machdep.h

[John Baldwin]

On Wednesday 02 November 2005 03:59 pm, Scott Long wrote:
> John Baldwin wrote:
> > jhb         2005-11-02 20:11:47 UTC
> >
> >   FreeBSD src repository
> >
> >   Modified files:
> >     sys/amd64/amd64      io_apic.c local_apic.c
> >     sys/amd64/include    apicvar.h intr_machdep.h
> >     sys/i386/i386        io_apic.c local_apic.c
> >     sys/i386/include     apicvar.h intr_machdep.h
> >   Log:
> >   Change the x86 code to allocate IDT vectors on-demand when an interrupt
> >   source is first enabled similar to how intr_event's now allocate
> > ithreads on-demand.  Previously, we would map IDT vectors 1:1 to IRQs. 
> > Since we only have 191 available IDT vectors for I/O interrupts, this
> > limited us to only supporting IRQs 0-190 corresponding to the first 190
> > I/O APIC intpins.  On many machines, however, each PCI-X bus has its own
> > APIC even though it only has 1 or 2 devices, thus, we were reserving
> > between 24 and 32 IRQs just for 1 or 2 devices and thus 24 or 32 IDT
> > vectors.  With this change, a machine with 100 IRQs but only 5 in use
> > will only use up 5 IDT vectors.  Also, this change provides an API
> > (apic_alloc_vector() and apic_free_vector()) that will allow a future MSI
> > interrupt source driver to request IDT vectors for use by MSI interrupts
> > on x86 machines.
> >
> >   Tested on:      amd64, i386
> >
> >   Revision  Changes    Path
> >   1.18      +84 -68    src/sys/amd64/amd64/io_apic.c
> >   1.19      +100 -22   src/sys/amd64/amd64/local_apic.c
> >   1.14      +3 -2      src/sys/amd64/include/apicvar.h
> >   1.7       +29 -3     src/sys/amd64/include/intr_machdep.h
> >   1.23      +84 -68    src/sys/i386/i386/io_apic.c
> >   1.20      +101 -23   src/sys/i386/i386/local_apic.c
> >   1.14      +3 -2      src/sys/i386/include/apicvar.h
> >   1.9       +29 -3     src/sys/i386/include/intr_machdep.h
>
> Excellent, thanks a lot.  The other savings here is the dozens of unused
> ithread stack pages and pcbs.

That was the earlier intr_event stuff. :-P

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org