From 60e684f0d66369add7aa49fc39785d2f26fe9169 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Sun, 26 Oct 2014 16:06:28 +0000 Subject: [PATCH] x86/irq: Fix XT-PIC-XT-PIC in /proc/interrupts Fix duplicate XT-PIC seen in /proc/interrupts on x86 systems that make use of 8259A Programmable Interrupt Controllers. Specifically convert output like this: CPU0 0: 76573 XT-PIC-XT-PIC timer 1: 11 XT-PIC-XT-PIC i8042 2: 0 XT-PIC-XT-PIC cascade 4: 8 XT-PIC-XT-PIC serial 6: 3 XT-PIC-XT-PIC floppy 7: 0 XT-PIC-XT-PIC parport0 8: 1 XT-PIC-XT-PIC rtc0 10: 448 XT-PIC-XT-PIC fddi0 12: 23 XT-PIC-XT-PIC eth0 14: 2464 XT-PIC-XT-PIC ide0 NMI: 0 Non-maskable interrupts ERR: 0 to one like this: CPU0 0: 122033 XT-PIC timer 1: 11 XT-PIC i8042 2: 0 XT-PIC cascade 4: 8 XT-PIC serial 6: 3 XT-PIC floppy 7: 0 XT-PIC parport0 8: 1 XT-PIC rtc0 10: 145 XT-PIC fddi0 12: 31 XT-PIC eth0 14: 2245 XT-PIC ide0 NMI: 0 Non-maskable interrupts ERR: 0 that is one like we used to have from ~2.2 till it was changed sometime. The rationale is there is no value in this duplicate information, it merely clutters output and looks ugly. We only have one handler for 8259A interrupts so there is no need to give it a name separate from the name already given to irq_chip. We could define meaningful names for handlers based on bits in the ELCR register on systems that have it or the value of the LTIM bit we use in ICW1 otherwise (hardcoded to 0 though with MCA support gone), to tell edge-triggered and level-triggered inputs apart. While that information does not affect 8259A interrupt handlers it could help people determine which lines are shareable and which are not. That is material for a separate change though. Any tools that parse /proc/interrupts are supposed not to be affected since it was many years we used the format this change converts back to. Signed-off-by: Maciej W. Rozycki Cc: Linus Torvalds Link: http://lkml.kernel.org/r/alpine.LFD.2.11.1410260147190.21390@eddie.linux-mips.org Signed-off-by: Ingo Molnar --- arch/x86/kernel/i8259.c | 3 +-- arch/x86/kernel/irqinit.c | 3 +-- 2 files changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/i8259.c b/arch/x86/kernel/i8259.c index 8af817105e29..e7cc5370cd2f 100644 --- a/arch/x86/kernel/i8259.c +++ b/arch/x86/kernel/i8259.c @@ -111,8 +111,7 @@ static void make_8259A_irq(unsigned int irq) { disable_irq_nosync(irq); io_apic_irqs &= ~(1<chip; - const char *name = chip->name; int i; #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC) @@ -79,7 +78,7 @@ void __init init_ISA_irqs(void) legacy_pic->init(0); for (i = 0; i < nr_legacy_irqs(); i++) - irq_set_chip_and_handler_name(i, chip, handle_level_irq, name); + irq_set_chip_and_handler(i, chip, handle_level_irq); } void __init init_IRQ(void) -- 2.20.1