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2008-02-08kernel: remove fastcall in kernel/*Harvey Harrison
[akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-14__do_IRQ does not check IRQ_DISABLED when IRQ_PER_CPU is setRuss Anderson
In __do_IRQ(), the normal case is that IRQ_DISABLED is checked and if set the handler (handle_IRQ_event()) is not called. Earlier in __do_IRQ(), if IRQ_PER_CPU is set the code does not check IRQ_DISABLED and calls the handler even though IRQ_DISABLED is set. This behavior seems unintentional. One user encountering this behavior is the CPE handler (in arch/ia64/kernel/mca.c). When the CPE handler encounters too many CPEs (such as a solid single bit error), it sets up a polling timer and disables the CPE interrupt (to avoid excessive overhead logging the stream of single bit errors). disable_irq_nosync() is called which sets IRQ_DISABLED. The IRQ_PER_CPU flag was previously set (in ia64_mca_late_init()). The net result is the CPE handler gets called even though it is marked disabled. If the behavior of not checking IRQ_DISABLED when IRQ_PER_CPU is set is intentional, it would be worthy of a comment describing the intended behavior. disable_irq_nosync() does call chip->disable() to provide a chipset specifiec interface for disabling the interrupt, which avoids this issue when used. Signed-off-by: Russ Anderson <rja@sgi.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09Fix Linuxdoc commentJeff Dike
A linuxdoc comment had fallen out of date - it refers to an argument which no longer exists. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08Add IRQF_IRQPOLL flag (common code)Bernhard Walle
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 <bwalle@suse.de> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Matthew Wilcox <willy@debian.org> Cc: Grant Grundler <grundler@google.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08Pad irq_desc to internode cacheline sizeRavikiran G Thirumalai
We noticed a drop in n/w performance due to the irq_desc being cacheline aligned rather than internode aligned. We see 50% of expected performance when two e1000 nics local to two different nodes have consecutive irq descriptors allocated, due to false sharing. Note that this patch does away with cacheline padding for the UP case, as it does not seem useful for UP configurations. Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org> Signed-off-by: Shai Fultheim <shai@scalex86.org> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.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>
2006-12-07[PATCH] lockdep: name some old style locksPeter Zijlstra
Name some of the remaning 'old_style_spin_init' locks Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-22Don't call "note_interrupt()" with irq descriptor lock heldLinus Torvalds
This reverts commit f72fa707604c015a6625e80f269506032d5430dc, and solves the problem that it tried to fix by simply making "__do_IRQ()" call the note_interrupt() function without the lock held, the way everybody else does. It should be noted that all interrupt handling code must never allow the descriptor actors to be entered "recursively" (that's why we do all the magic IRQ_PENDING stuff in the first place), so there actually is exclusion at that much higher level, even in the absense of locking. Acked-by: Vivek Goyal <vgoyal@in.ibm.com> Acked-by:Pavel Emelianov <xemul@openvz.org> Cc: Andrew Morton <akpm@osdl.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Adrian Bunk <bunk@stusta.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-05IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells
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 <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-09-26[PATCH] FRV: permit __do_IRQ() to be dispensed withDavid Howells
Permit __do_IRQ() to be dispensed with based on a configuration option. Signed-off-by: David Howells <dhowells@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01[PATCH] kerneldoc for handle_bad_irq()Henrik Kretzschmar
Adds the description of the parameters from handle_bad_irq(). Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03[PATCH] lockdep: annotate enable_in_hardirq()Ingo Molnar
Make use of local_irq_enable_in_hardirq() API to annotate places that enable hardirqs in hardirq context. Has no effect on non-lockdep kernels. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03[PATCH] lockdep: annotate genirqIngo Molnar
Teach special (recursive) locking code to the lock validator. Has no effect on non-lockdep kernels. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02[PATCH] genirq: ARM dyntick cleanupThomas Gleixner
Linus: "The hacks in kernel/irq/handle.c are really horrid. REALLY horrid." They are indeed. Move the dyntick quirks to ARM where they belong. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02Merge branch 'genirq' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'genirq' of master.kernel.org:/home/rmk/linux-2.6-arm: (24 commits) [ARM] 3683/2: ARM: Convert at91rm9200 to generic irq handling [ARM] 3682/2: ARM: Convert ixp4xx to generic irq handling [ARM] 3702/1: ARM: Convert ixp23xx to generic irq handling [ARM] 3701/1: ARM: Convert plat-omap to generic irq handling [ARM] 3700/1: ARM: Convert lh7a40x to generic irq handling [ARM] 3699/1: ARM: Convert s3c2410 to generic irq handling [ARM] 3698/1: ARM: Convert sa1100 to generic irq handling [ARM] 3697/1: ARM: Convert shark to generic irq handling [ARM] 3696/1: ARM: Convert clps711x to generic irq handling [ARM] 3694/1: ARM: Convert ecard driver to generic irq handling [ARM] 3693/1: ARM: Convert omap1 to generic irq handling [ARM] 3691/1: ARM: Convert imx to generic irq handling [ARM] 3688/1: ARM: Convert clps7500 to generic irq handling [ARM] 3687/1: ARM: Convert integrator to generic irq handling [ARM] 3685/1: ARM: Convert pxa to generic irq handling [ARM] 3684/1: ARM: Convert l7200 to generic irq handling [ARM] 3681/1: ARM: Convert ixp2000 to generic irq handling [ARM] 3680/1: ARM: Convert footbridge to generic irq handling [ARM] 3695/1: ARM drivers/pcmcia: Fixup includes [ARM] 3689/1: ARM drivers/input/touchscreen: Fixup includes ... Manual conflict resolved in kernel/irq/handle.c (butt-ugly ARM tickless code).
2006-07-02[PATCH] irq-flags: generic irq: Use the new IRQF_ constantsThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-01[ARM] 3690/1: genirq: Introduce and make use of dummy irq chipThomas Gleixner
Patch from Thomas Gleixner From: Thomas Gleixner <tglx@linutronix.de> ARM has a couple of really dumb interrupt controllers. Implement a generic one and fixup the ARM migration. ARM reused the no_irq_chip for this purpose, but this does not work out for platforms which are not converted to the new interrupt type handling model. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-07-01[ARM] 3679/1: ARM: Make ARM dyntick implementation work with genirqThomas Gleixner
Patch from Thomas Gleixner From: Thomas Gleixner <tglx@linutronix.de> Make the ARM dyntick implementation work with the generic irq code. This hopefully goes away once we consolidated the dyntick implementations. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-06-29[PATCH] genirq: more verbose debugging on unexpected IRQ vectorsIngo Molnar
One frequent sign of IRQ handling bugs is the appearance of unexpected vectors. Print out all the IRQ state in that case. We dont want this patch upstream, but it is useful during initial testing. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: cleanup: no_irq_type -> no_irq_chip renameIngo Molnar
Rename no_irq_type to no_irq_chip. 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[PATCH] genirq: add handle_bad_irq()Ingo Molnar
Handle bad IRQ vectors via the irqchip mechanism. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: coreThomas Gleixner
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[PATCH] genirq: update copyrightsIngo Molnar
Update/add copyrights in the generic IRQ code. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: add IRQ_NOAUTOEN supportThomas Gleixner
Enable platforms to disable the automatic enabling of freshly set up irqs. 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[PATCH] genirq: cleanup: no_irq_type cleanupsIngo Molnar
Clean up no_irq_type: share the NOP functions where possible, and properly name the ack_bad() function. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: doc: handle_IRQ_event() and __do_IRQ() commentsIngo Molnar
Document handle_IRQ_event() and __do_IRQ(). Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: cleanup: reduce irq_desc_t use, mark it obsoleteIngo Molnar
Cleanup: remove irq_desc_t use from the generic IRQ code, and mark it obsolete. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: cleanup: misc code cleanupsIngo Molnar
Assorted code cleanups to the generic IRQ code. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: cleanup: remove fastcallIngo Molnar
Now that i386 defaults to regparm, explicit uses of fastcall are not needed anymore. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: cleanup: merge irq_affinity[] into irq_desc[]Ingo Molnar
Consolidation: remove the irq_affinity[NR_IRQS] array and move it into the irq_desc[NR_IRQS].affinity field. [akpm@osdl.org: sparc64 build fix] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29[PATCH] genirq: rename desc->handler to desc->chipIngo Molnar
This patch-queue improves the generic IRQ layer to be truly generic, by adding various abstractions and features to it, without impacting existing functionality. While the queue can be best described as "fix and improve everything in the generic IRQ layer that we could think of", and thus it consists of many smaller features and lots of cleanups, the one feature that stands out most is the new 'irq chip' abstraction. The irq-chip abstraction is about describing and coding and IRQ controller driver by mapping its raw hardware capabilities [and quirks, if needed] in a straightforward way, without having to think about "IRQ flow" (level/edge/etc.) type of details. This stands in contrast with the current 'irq-type' model of genirq architectures, which 'mixes' raw hardware capabilities with 'flow' details. The patchset supports both types of irq controller designs at once, and converts i386 and x86_64 to the new irq-chip design. As a bonus side-effect of the irq-chip approach, chained interrupt controllers (master/slave PIC constructs, etc.) are now supported by design as well. The end result of this patchset intends to be simpler architecture-level code and more consolidation between architectures. We reused many bits of code and many concepts from Russell King's ARM IRQ layer, the merging of which was one of the motivations for this patchset. This patch: rename desc->handler to desc->chip. Originally i did not want to do this, because it's a big patch. But having both "desc->handler", "desc->handle_irq" and "action->handler" caused a large degree of confusion and made the code appear alot less clean than it truly is. I have also attempted a dual approach as well by introducing a desc->chip alias - but that just wasnt robust enough and broke frequently. So lets get over with this quickly. The conversion was done automatically via scripts and converts all the code in the kernel. This renaming patch is the first one amongst the patches, so that the remaining patches can stay flexible and can be merged and split up without having some big monolithic patch act as a merge barrier. [akpm@osdl.org: build fix] [akpm@osdl.org: another build fix] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23[PATCH] adjust handle_IRR_event() return typeJan Beulich
Correct the return type of handle_IRQ_event() (inconsistency noticed during Xen development), and remove redundant declarations. The return type adjustment required breaking out the definition of irqreturn_t into a separate header, in order to satisfy current include order dependencies. Signed-off-by: Jan Beulich <jbeulich@novell.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Hirokazu Takata <takata.hirokazu@renesas.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-28Don't call a NULL ack function in the generic IRQ code.Paul Mackerras
Some IRQ controllers don't need an ack function (e.g. OpenPIC on PPC platforms) and for them we'd rather not have the overhead of doing an indirect call to a function that does nothing. Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-09-07[PATCH] CHECK_IRQ_PER_CPU() to avoid dead code in __do_IRQ()Karsten Wiese
IRQ_PER_CPU is not used by all architectures. This patch introduces the macros ARCH_HAS_IRQ_PER_CPU and CHECK_IRQ_PER_CPU() to avoid the generation of dead code in __do_IRQ(). ARCH_HAS_IRQ_PER_CPU is defined by architectures using IRQ_PER_CPU in their include/asm_ARCH/irq.h file. Through grepping the tree I found the following architectures currently use IRQ_PER_CPU: cris, ia64, ppc, ppc64 and parisc. Signed-off-by: Karsten Wiese <annabellesgarden@yahoo.de> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28[PATCH] irqpollAlan Cox
Anyone reporting a stuck IRQ should try these options. Its effectiveness varies we've found in the Fedora case. Quite a few systems with misdescribed IRQ routing just work when you use irqpoll. It also fixes up the VIA systems although thats now fixed with the VIA quirk (which we could just make default as its what Redmond OS does but Linus didn't like it historically). A small number of systems have jammed IRQ sources or misdescribes that cause an IRQ that we have no handler registered anywhere for. In those cases it doesn't help. Signed-off-by: Alan Cox <number6@the-village.bc.nu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-28[PATCH] drop note_interrupt() for per-CPU for proper scalingJohn Hawkes
The "unhandled interrupts" catcher, note_interrupt(), increments a global desc->irq_count and grossly damages scaling of very large systems, e.g., >192p ia64 Altix, because of this highly contented cacheline, especially for timer interrupts. 384p is severely crippled, and 512p is unuseable. All calls to note_interrupt() can be disabled by booting with "noirqdebug", but this disables the useful interrupt checking for all interrupts. I propose eliminating note_interrupt() for all per-CPU interrupts. This was the behavior of linux-2.6.10 and earlier, but in 2.6.11 a code restructuring added a call to note_interrupt() for per-CPU interrupts. Besides, note_interrupt() is a bit racy for concurrent CPU calls anyway, as the desc->irq_count++ increment isn't atomic (which, if done, would make scaling even worse). Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-17[PATCH] spurious interrupt fixZhang, Yanmin
On my IA64 machine, after kernel 2.6.12-rc3 boots, an edge-triggered interrupt (IRQ 46) keeps triggered over and over again. There is no IRQ 46 interrupt action handler. It has lots of impact on performance. Kernel 2.6.10 and its prior versions have no the problem. Basically, kernel 2.6.10 will mask the spurious edge interrupt if the interrupt is triggered for the second time and its status includes IRQ_DISABLE|IRQ_PENDING. Originally, IA64 kernel has its own specific _irq_desc definitions in file arch/ia64/kernel/irq.c. The definition initiates _irq_desc[irq].status to IRQ_DISABLE. Since kernel 2.6.11, it was moved to architecture independent codes, i.e. kernel/irq/handle.c, but kernel/irq/handle.c initiates _irq_desc[irq].status to 0 instead of IRQ_DISABLE. Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!