Commit Graph

10 Commits

Author SHA1 Message Date
Bartlomiej Zolnierkiewicz c36ba80ea0 irq: Remove superfluous NULL pointer check in check_irq_resend()
This takes care of the following entry from Dan's list:

kernel/irq/resend.c +73 check_irq_resend(17) warning: variable derefenced before check 'desc->chip'

Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Eugene Teo <eteo@redhat.com>
Cc: Julia Lawall <julia@diku.dk>
LKML-Reference: <200908062146.03638.bzolnier@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:44:29 +02:00
Yinghai Lu 08678b0841 generic: sparse irqs: use irq_desc() together with dyn_array, instead of irq_desc[]
add CONFIG_HAVE_SPARSE_IRQ to for use condensed array.
Get rid of irq_desc[] array assumptions.

Preallocate 32 irq_desc, and irq_desc() will try to get more.

( No change in functionality is expected anywhere, except the odd build
  failure where we missed a code site or where a crossing commit itroduces
  new irq_desc[] usage. )

v2: according to Eric, change get_irq_desc() to irq_desc()

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:52:29 +02:00
Yinghai Lu 85c0f90978 irq: introduce nr_irqs
at this point nr_irqs is equal NR_IRQS

convert a few easy users from NR_IRQS to dynamic nr_irqs.

v2: according to Eric, we need to take care of arch without generic_hardirqs

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:52:05 +02:00
Thomas Gleixner 2464286ace genirq: suppress resend of level interrupts
Level type interrupts are resent by the interrupt hardware when they are
still active at irq_enable().

Suppress the resend mechanism for interrupts marked as level.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-12 11:05:45 -07:00
Linus Torvalds 88ffc35059 Revert "genirq: temporary fix for level-triggered IRQ resend"
This reverts commit 0fc4969b86.  It was
always meant to be temporary, but it's generating more useless noise
than anything else, and we probably should never have done it in the
generic kernel (only had the people involved test it on their own).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-09 08:10:16 -07:00
Thomas Gleixner 0fc4969b86 genirq: temporary fix for level-triggered IRQ resend
Marcin Slusarz reported a ne2k-pci "hung network interface" regression.

delayed disable relies on the ability to re-trigger the interrupt in the
case that a real interrupt happens after the software disable was set.
In this case we actually disable the interrupt on the hardware level
_after_ it occurred.

On enable_irq, we need to re-trigger the interrupt. On i386 this relies
on a hardware resend mechanism (send_IPI_self()).

Actually we only need the resend for edge type interrupts. Level type
interrupts come back once enable_irq() re-enables the interrupt line.

I assume that the interrupt in question is level triggered because it is
shared and above the legacy irqs 0-15:

	17:         12   IO-APIC-fasteoi   eth1, eth0

Looking into the IO_APIC code, the resend via send_IPI_self() happens
unconditionally. So the resend is done for level and edge interrupts.
This makes the problem more mysterious.

The code in question lib8390.c does

	disable_irq();
	fiddle_with_the_network_card_hardware()
	enable_irq();

The fiddle_with_the_network_card_hardware() might cause interrupts,
which are cleared in the same code path again,

Marcin found that when he disables the irq line on the hardware level
(removing the delayed disable) the card is kept alive.

So the difference is that we can get a resend on enable_irq, when an
interrupt happens during the time, where we are in the disabled region.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-01 20:46:22 -07:00
Frederik Deweerdt e317c8ccaa [PATCH] ixp4xxdefconfig arm fixes
With the following patch, the ixp4xxdefconfig builds correctly.  I'll
test some more configs if I get some time.

Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-06 12:11:08 -07:00
Imre Deak e1ed7ac77b [PATCH] genirq: fix typo in IRQ resend
Fix a bug where the IRQ_PENDING flag is never cleared and the ISR is called
endlessly without an actual interrupt.

Signed-off-by: Imre Deak <imre.deak@solidboot.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-16 12:54:30 -07:00
Thomas Gleixner 6a6de9ef58 [PATCH] genirq: core
Core genirq support: add the irq-chip and irq-flow abstractions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Thomas Gleixner a4633adcdb [PATCH] genirq: add genirq sw IRQ-retrigger
Enable platforms that do not have a hardware-assisted hardirq-resend mechanism
to resend them via a softirq-driven IRQ emulation mechanism.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:23 -07:00