linux-stable/kernel/irq
Alan Cox 4f27c00bf8 Improve behaviour of spurious IRQ detect
Currently we handle spurious IRQ activity based upon seeing a lot of
invalid interrupts, and we clear things back on the base of lots of valid
interrupts.

Unfortunately in some cases you get legitimate invalid interrupts caused by
timing asynchronicity between the PCI bus and the APIC bus when disabling
interrupts and pulling other tricks.  In this case although the spurious
IRQs are not a problem our unhandled counters didn't clear and they act as
a slow running timebomb.  (This is effectively what the serial port/tty
problem that was fixed by clearing counters when registering a handler
showed up)

It's easy enough to add a second parameter - time.  This means that if we
see a regular stream of harmless spurious interrupts which are not harming
processing we don't go off and do something stupid like disable the IRQ
after a month of running.  OTOH lockups and performance killers show up a
lot more than 10/second

[akpm@linux-foundation.org: cleanup]
Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:46 -07:00
..
autoprobe.c [PATCH] genirq: add handle_bad_irq() 2006-06-29 10:26:24 -07:00
chip.c MSI: arch must connect the irq and the msi_desc 2007-05-02 19:02:38 -07:00
devres.c [PATCH] irq-devres: fix failure path of devm_request_irq() 2007-04-07 10:05:21 -07:00
handle.c Fix Linuxdoc comment 2007-05-09 12:30:48 -07:00
internals.h [PATCH] genirq: more verbose debugging on unexpected IRQ vectors 2006-06-29 10:26:25 -07:00
Makefile [PATCH] sort the devres mess out 2007-02-11 11:18:07 -08:00
manage.c IRQ: check for PERCPU flag only when adding first irqaction 2007-05-08 11:15:06 -07:00
migration.c [PATCH] genirq: Mask irqs when migrating them. 2007-02-26 10:34:08 -08:00
proc.c [IA64] SN: validate smp_affinity mask on intr redirect 2007-05-11 09:35:38 -07:00
resend.c [PATCH] ixp4xxdefconfig arm fixes 2006-10-06 12:11:08 -07:00
spurious.c Improve behaviour of spurious IRQ detect 2007-07-16 09:05:46 -07:00