kernel.git/kernel/irq/spurious.c, branch linux-2.6.24.y

Improve behaviour of spurious IRQ detect

2007-07-16T16:05:46Z

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 Cc: Ingo Molnar Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Fix crash with irqpoll due to the IRQF_IRQPOLL flag testing

2007-05-24T15:37:14Z

With irqpoll enabled, trying to test the IRQF_IRQPOLL flag in the actions would cause a NULL pointer dereference if no action was installed (for example, the driver might have been unloaded with interrupts still pending). So be a bit more careful about testing the flag by making sure to test for that case. (The actual _change_ is trivial, the patch is more than a one-liner because I rewrote the testing to also be much more readable. Original (discarded) bugfix by Bernhard Walle. Cc: Bernhard Walle Tested-by: Vivek Goyal Signed-off-by: Linus Torvalds

Add IRQF_IRQPOLL flag (common code)

2007-05-08T18:15:22Z

irqpoll is broken on some architectures that don't use the IRQ 0 for the timer interrupt like IA64. This patch adds a IRQF_IRQPOLL flag. Each architecture is handled in a separate pach. As I left the irq == 0 as condition, this should not break existing architectures that use timer_irq == 0 and that I did't address with that patch (because I don't know). This patch: This patch adds a IRQF_IRQPOLL flag that the interrupt registration code could use for the interrupt it wants to use for IRQ polling. Because this must not be the timer interrupt, an additional flag was added instead of re-using the IRQF_TIMER constant. Until all architectures will have an IRQF_IRQPOLL interrupt, irq == 0 will stay as alternative as it should not break anything. Also, note_interrupt() is called on CPU-specific interrupts to be used as interrupt source for IRQ polling. Signed-off-by: Bernhard Walle Cc: Russell King Cc: Kyle McMartin Cc: Matthew Wilcox Cc: Grant Grundler Cc: Paul Mundt Cc: "Luck, Tony" Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] x86-64: Make noirqdebug_setup function non init to fix modpost warning

2007-01-11T00:52:44Z

o noirqdebug_setup() is __init but it is being called by quirk_intel_irqbalance() which if of type __devinit. If CONFIG_HOTPLUG=y, quirk_intel_irqbalance() is put into text section and it is wrong to call a function in __init section. o MODPOST flags this on i386 if CONFIG_RELOCATABLE=y WARNING: vmlinux - Section mismatch: reference to .init.text:noirqdebug_setup from .text between 'quirk_intel_irqbalance' (at offset 0xc010969e) and 'i8237A_suspend' o Make noirqdebug_setup() non-init. Signed-off-by: Vivek Goyal Signed-off-by: Andi Kleen

IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

2006-10-05T14:10:12Z

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

[PATCH] irq-flags: generic irq: Use the new IRQF_ constants

2006-07-02T20:58:49Z

Signed-off-by: Thomas Gleixner Cc: Ingo Molnar Cc: "David S. Miller" Cc: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] genirq: add irq-chip support

2006-06-29T17:26:24Z

Enable platforms to use the irq-chip and irq-flow abstractions: allow setting of the chip, the type and provide highlevel handlers for common irq-flows. [rostedt@goodmis.org: misroute-irq: Don't call desc->chip->end because of edge interrupts] Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Cc: Benjamin Herrenschmidt Signed-off-by: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] genirq: core

2006-06-29T17:26:24Z

Core genirq support: add the irq-chip and irq-flow abstractions. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] genirq: cleanup: reduce irq_desc_t use, mark it obsolete

2006-06-29T17:26:22Z

Cleanup: remove irq_desc_t use from the generic IRQ code, and mark it obsolete. Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] genirq: cleanup: misc code cleanups

2006-06-29T17:26:22Z

Assorted code cleanups to the generic IRQ code. Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds