From: Ingo Molnar x86 port of generic hardirq handling. Signed-off-by: Ingo Molnar Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton --- 25-akpm/arch/i386/Kconfig | 7 25-akpm/arch/i386/kernel/i386_ksyms.c | 4 25-akpm/arch/i386/kernel/io_apic.c | 2 25-akpm/arch/i386/kernel/irq.c | 1146 +++------------------------------- 25-akpm/arch/i386/kernel/process.c | 2 25-akpm/arch/i386/kernel/vm86.c | 2 25-akpm/include/asm-i386/hardirq.h | 58 - 25-akpm/include/asm-i386/hw_irq.h | 2 25-akpm/include/asm-i386/irq.h | 31 9 files changed, 151 insertions(+), 1103 deletions(-) diff -puN arch/i386/Kconfig~generic-irq-subsystem-x86-port arch/i386/Kconfig --- 25/arch/i386/Kconfig~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/arch/i386/Kconfig Fri Oct 1 14:25:52 2004 @@ -1194,6 +1194,13 @@ source "crypto/Kconfig" source "lib/Kconfig" +# +# Use the generic interrupt handling code in kernel/hardirq.c: +# +config GENERIC_HARDIRQS + bool + default y + config X86_SMP bool depends on SMP && !X86_VOYAGER diff -puN arch/i386/kernel/i386_ksyms.c~generic-irq-subsystem-x86-port arch/i386/kernel/i386_ksyms.c --- 25/arch/i386/kernel/i386_ksyms.c~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/arch/i386/kernel/i386_ksyms.c Fri Oct 1 14:25:52 2004 @@ -76,9 +76,6 @@ EXPORT_SYMBOL_GPL(kernel_fpu_begin); EXPORT_SYMBOL(__ioremap); EXPORT_SYMBOL(ioremap_nocache); EXPORT_SYMBOL(iounmap); -EXPORT_SYMBOL(enable_irq); -EXPORT_SYMBOL(disable_irq); -EXPORT_SYMBOL(disable_irq_nosync); EXPORT_SYMBOL(probe_irq_mask); EXPORT_SYMBOL(kernel_thread); EXPORT_SYMBOL(pm_idle); @@ -146,7 +143,6 @@ EXPORT_SYMBOL(__write_lock_failed); EXPORT_SYMBOL(__read_lock_failed); /* Global SMP stuff */ -EXPORT_SYMBOL(synchronize_irq); EXPORT_SYMBOL(smp_call_function); /* TLB flushing */ diff -puN arch/i386/kernel/io_apic.c~generic-irq-subsystem-x86-port arch/i386/kernel/io_apic.c --- 25/arch/i386/kernel/io_apic.c~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/arch/i386/kernel/io_apic.c Fri Oct 1 14:25:52 2004 @@ -255,8 +255,6 @@ static void set_ioapic_affinity_irq(unsi # define Dprintk(x...) # endif -extern cpumask_t irq_affinity[NR_IRQS]; - cpumask_t __cacheline_aligned pending_irq_balance_cpumask[NR_IRQS]; #define IRQBALANCE_CHECK_ARCH -999 diff -puN arch/i386/kernel/irq.c~generic-irq-subsystem-x86-port arch/i386/kernel/irq.c --- 25/arch/i386/kernel/irq.c~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/arch/i386/kernel/irq.c Fri Oct 1 14:25:52 2004 @@ -3,437 +3,47 @@ * * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar * - * This file contains the code used by various IRQ handling routines: - * asking for different IRQ's should be done through these routines - * instead of just grabbing them. Thus setups with different IRQ numbers - * shouldn't result in any weird surprises, and installing new handlers - * should be easier. + * This file contains the lowest level x86-specific interrupt + * entry, irq-stacks and irq statistics code. All the remaining + * irq logic is done by the generic kernel/irq/ code and + * by the x86-specific irq controller code. (e.g. i8259.c and + * io_apic.c.) */ -/* - * (mostly architecture independent, will move to kernel/irq.c in 2.5.) - * - * IRQs are in fact implemented a bit like signal handlers for the kernel. - * Naturally it's not a 1:1 relation, but there are similarities. - */ - -#include -#include +#include #include -#include -#include -#include +#include #include -#include -#include -#include -#include -#include #include -#include -#include -#include -#include - -#include -#include -#include -#include -#include -#include -#include -#include -#include - -/* - * Linux has a controller-independent x86 interrupt architecture. - * every controller has a 'controller-template', that is used - * by the main code to do the right thing. Each driver-visible - * interrupt source is transparently wired to the apropriate - * controller. Thus drivers need not be aware of the - * interrupt-controller. - * - * Various interrupt controllers we handle: 8259 PIC, SMP IO-APIC, - * PIIX4's internal 8259 PIC and SGI's Visual Workstation Cobalt (IO-)APIC. - * (IO-APICs assumed to be messaging to Pentium local-APICs) - * - * the code is designed to be easily extended with new/different - * interrupt controllers, without having to do assembly magic. - */ -/* - * Controller mappings for all interrupt sources: - */ -irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned = { - [0 ... NR_IRQS-1] = { - .handler = &no_irq_type, - .lock = SPIN_LOCK_UNLOCKED - } -}; - -static void register_irq_proc (unsigned int irq); - -/* - * per-CPU IRQ handling stacks - */ #ifdef CONFIG_4KSTACKS -union irq_ctx *hardirq_ctx[NR_CPUS]; -union irq_ctx *softirq_ctx[NR_CPUS]; -#endif - -/* - * Special irq handlers. - */ - -irqreturn_t no_action(int cpl, void *dev_id, struct pt_regs *regs) -{ return IRQ_NONE; } - /* - * Generic no controller code + * per-CPU IRQ handling contexts (thread information and stack) */ - -static void enable_none(unsigned int irq) { } -static unsigned int startup_none(unsigned int irq) { return 0; } -static void disable_none(unsigned int irq) { } -static void ack_none(unsigned int irq) -{ -/* - * 'what should we do if we get a hw irq event on an illegal vector'. - * each architecture has to answer this themselves, it doesn't deserve - * a generic callback i think. - */ -#ifdef CONFIG_X86 - printk("unexpected IRQ trap at vector %02x\n", irq); -#ifdef CONFIG_X86_LOCAL_APIC - /* - * Currently unexpected vectors happen only on SMP and APIC. - * We _must_ ack these because every local APIC has only N - * irq slots per priority level, and a 'hanging, unacked' IRQ - * holds up an irq slot - in excessive cases (when multiple - * unexpected vectors occur) that might lock up the APIC - * completely. - */ - ack_APIC_irq(); -#endif -#endif -} - -/* startup is the same as "enable", shutdown is same as "disable" */ -#define shutdown_none disable_none -#define end_none enable_none - -struct hw_interrupt_type no_irq_type = { - "none", - startup_none, - shutdown_none, - enable_none, - disable_none, - ack_none, - end_none +union irq_ctx { + struct thread_info tinfo; + u32 stack[THREAD_SIZE/sizeof(u32)]; }; -atomic_t irq_err_count; -#if defined(CONFIG_X86_IO_APIC) && defined(APIC_MISMATCH_DEBUG) -atomic_t irq_mis_count; -#endif - -/* - * Generic, controller-independent functions: - */ - -int show_interrupts(struct seq_file *p, void *v) -{ - int i = *(loff_t *) v, j; - struct irqaction * action; - unsigned long flags; - - if (i == 0) { - seq_printf(p, " "); - for (j=0; jtypename); - seq_printf(p, " %s", action->name); - - for (action=action->next; action; action = action->next) - seq_printf(p, ", %s", action->name); - - seq_putc(p, '\n'); -skip: - spin_unlock_irqrestore(&irq_desc[i].lock, flags); - } else if (i == NR_IRQS) { - seq_printf(p, "NMI: "); - for (j = 0; j < NR_CPUS; j++) - if (cpu_online(j)) - seq_printf(p, "%10u ", nmi_count(j)); - seq_putc(p, '\n'); -#ifdef CONFIG_X86_LOCAL_APIC - seq_printf(p, "LOC: "); - for (j = 0; j < NR_CPUS; j++) - if (cpu_online(j)) - seq_printf(p, "%10u ", irq_stat[j].apic_timer_irqs); - seq_putc(p, '\n'); -#endif - seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); -#if defined(CONFIG_X86_IO_APIC) && defined(APIC_MISMATCH_DEBUG) - seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count)); -#endif - } - return 0; -} - - - - -#ifdef CONFIG_SMP -inline void synchronize_irq(unsigned int irq) -{ - while (irq_desc[irq].status & IRQ_INPROGRESS) - cpu_relax(); -} +static union irq_ctx *hardirq_ctx[NR_CPUS]; +static union irq_ctx *softirq_ctx[NR_CPUS]; #endif /* - * This should really return information about whether - * we should do bottom half handling etc. Right now we - * end up _always_ checking the bottom half, which is a - * waste of time and is not what some drivers would - * prefer. - */ -asmlinkage int handle_IRQ_event(unsigned int irq, - struct pt_regs *regs, struct irqaction *action) -{ - int status = 1; /* Force the "do bottom halves" bit */ - int ret, retval = 0; - - if (!(action->flags & SA_INTERRUPT)) - local_irq_enable(); - - do { - ret = action->handler(irq, action->dev_id, regs); - if (ret == IRQ_HANDLED) - status |= action->flags; - retval |= ret; - action = action->next; - } while (action); - if (status & SA_SAMPLE_RANDOM) - add_interrupt_randomness(irq); - local_irq_disable(); - return retval; -} - -static void __report_bad_irq(int irq, irq_desc_t *desc, irqreturn_t action_ret) -{ - struct irqaction *action; - - if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) { - printk(KERN_ERR "irq event %d: bogus return value %x\n", - irq, action_ret); - } else { - printk(KERN_ERR "irq %d: nobody cared!\n", irq); - } - dump_stack(); - printk(KERN_ERR "handlers:\n"); - action = desc->action; - do { - printk(KERN_ERR "[<%p>]", action->handler); - print_symbol(" (%s)", - (unsigned long)action->handler); - printk("\n"); - action = action->next; - } while (action); -} - -static void report_bad_irq(int irq, irq_desc_t *desc, irqreturn_t action_ret) -{ - static int count = 100; - - if (count) { - count--; - __report_bad_irq(irq, desc, action_ret); - } -} - -static int noirqdebug; - -static int __init noirqdebug_setup(char *str) -{ - noirqdebug = 1; - printk("IRQ lockup detection disabled\n"); - return 1; -} - -__setup("noirqdebug", noirqdebug_setup); - -/* - * If 99,900 of the previous 100,000 interrupts have not been handled then - * assume that the IRQ is stuck in some manner. Drop a diagnostic and try to - * turn the IRQ off. - * - * (The other 100-of-100,000 interrupts may have been a correctly-functioning - * device sharing an IRQ with the failing one) - * - * Called under desc->lock - */ -static void note_interrupt(int irq, irq_desc_t *desc, irqreturn_t action_ret) -{ - if (action_ret != IRQ_HANDLED) { - desc->irqs_unhandled++; - if (action_ret != IRQ_NONE) - report_bad_irq(irq, desc, action_ret); - } - - desc->irq_count++; - if (desc->irq_count < 100000) - return; - - desc->irq_count = 0; - if (desc->irqs_unhandled > 99900) { - /* - * The interrupt is stuck - */ - __report_bad_irq(irq, desc, action_ret); - /* - * Now kill the IRQ - */ - printk(KERN_EMERG "Disabling IRQ #%d\n", irq); - desc->status |= IRQ_DISABLED; - desc->handler->disable(irq); - } - desc->irqs_unhandled = 0; -} - -/* - * Generic enable/disable code: this just calls - * down into the PIC-specific version for the actual - * hardware disable after having gotten the irq - * controller lock. - */ - -/** - * disable_irq_nosync - disable an irq without waiting - * @irq: Interrupt to disable - * - * Disable the selected interrupt line. Disables and Enables are - * nested. - * Unlike disable_irq(), this function does not ensure existing - * instances of the IRQ handler have completed before returning. - * - * This function may be called from IRQ context. - */ - -inline void disable_irq_nosync(unsigned int irq) -{ - irq_desc_t *desc = irq_desc + irq; - unsigned long flags; - - spin_lock_irqsave(&desc->lock, flags); - if (!desc->depth++) { - desc->status |= IRQ_DISABLED; - desc->handler->disable(irq); - } - spin_unlock_irqrestore(&desc->lock, flags); -} - -/** - * disable_irq - disable an irq and wait for completion - * @irq: Interrupt to disable - * - * Disable the selected interrupt line. Enables and Disables are - * nested. - * This function waits for any pending IRQ handlers for this interrupt - * to complete before returning. If you use this function while - * holding a resource the IRQ handler may need you will deadlock. - * - * This function may be called - with care - from IRQ context. - */ - -void disable_irq(unsigned int irq) -{ - irq_desc_t *desc = irq_desc + irq; - disable_irq_nosync(irq); - if (desc->action) - synchronize_irq(irq); -} - -/** - * enable_irq - enable handling of an irq - * @irq: Interrupt to enable - * - * Undoes the effect of one call to disable_irq(). If this - * matches the last disable, processing of interrupts on this - * IRQ line is re-enabled. - * - * This function may be called from IRQ context. - */ - -void enable_irq(unsigned int irq) -{ - irq_desc_t *desc = irq_desc + irq; - unsigned long flags; - - spin_lock_irqsave(&desc->lock, flags); - switch (desc->depth) { - case 1: { - unsigned int status = desc->status & ~IRQ_DISABLED; - desc->status = status; - if ((status & (IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) { - desc->status = status | IRQ_REPLAY; - hw_resend_irq(desc->handler,irq); - } - desc->handler->enable(irq); - /* fall-through */ - } - default: - desc->depth--; - break; - case 0: - printk("enable_irq(%u) unbalanced from %p\n", irq, - __builtin_return_address(0)); - } - spin_unlock_irqrestore(&desc->lock, flags); -} - -/* * do_IRQ handles all normal device IRQ's (the special * SMP cross-CPU interrupts have their own specific * handlers). */ asmlinkage unsigned int do_IRQ(struct pt_regs regs) { - /* - * We ack quickly, we don't want the irq controller - * thinking we're snobs just because some other CPU has - * disabled global interrupts (we have already done the - * INT_ACK cycles, it's too late to try to pretend to the - * controller that we aren't taking the interrupt). - * - * 0 return value means that this irq is already being - * handled by some other CPU. (or is disabled) - */ - int irq = regs.orig_eax & 0xff; /* high bits used in ret_from_ code */ - irq_desc_t *desc = irq_desc + irq; - struct irqaction * action; - unsigned int status; + /* high bits used in ret_from_ code */ + int irq = regs.orig_eax & 0xff; +#ifdef CONFIG_4KSTACKS + union irq_ctx *curctx, *irqctx; + u32 *isp; +#endif irq_enter(); - #ifdef CONFIG_DEBUG_STACKOVERFLOW /* Debugging check for stack overflow: is there less than 1KB free? */ { @@ -448,642 +58,54 @@ asmlinkage unsigned int do_IRQ(struct pt } } #endif - kstat_this_cpu.irqs[irq]++; - spin_lock(&desc->lock); - desc->handler->ack(irq); - /* - REPLAY is when Linux resends an IRQ that was dropped earlier - WAITING is used by probe to mark irqs that are being tested - */ - status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING); - status |= IRQ_PENDING; /* we _want_ to handle it */ - /* - * If the IRQ is disabled for whatever reason, we cannot - * use the action we have. - */ - action = NULL; - if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) { - action = desc->action; - status &= ~IRQ_PENDING; /* we commit to handling */ - status |= IRQ_INPROGRESS; /* we are handling it */ - } - desc->status = status; +#ifdef CONFIG_4KSTACKS - /* - * If there is no IRQ handler or it was disabled, exit early. - Since we set PENDING, if another processor is handling - a different instance of this same irq, the other processor - will take care of it. - */ - if (unlikely(!action)) - goto out; + curctx = (union irq_ctx *) current_thread_info(); + irqctx = hardirq_ctx[smp_processor_id()]; /* - * Edge triggered interrupts need to remember - * pending events. - * This applies to any hw interrupts that allow a second - * instance of the same irq to arrive while we are in do_IRQ - * or in the handler. But the code here only handles the _second_ - * instance of the irq, not the third or fourth. So it is mostly - * useful for irq hardware that does not mask cleanly in an - * SMP environment. + * this is where we switch to the IRQ stack. However, if we are + * already using the IRQ stack (because we interrupted a hardirq + * handler) we can't do that and just have to keep using the + * current stack (which is the irq stack already after all) */ -#ifdef CONFIG_4KSTACKS - - for (;;) { - irqreturn_t action_ret; - u32 *isp; - union irq_ctx * curctx; - union irq_ctx * irqctx; - - curctx = (union irq_ctx *) current_thread_info(); - irqctx = hardirq_ctx[smp_processor_id()]; - - spin_unlock(&desc->lock); - - /* - * this is where we switch to the IRQ stack. However, if we are already using - * the IRQ stack (because we interrupted a hardirq handler) we can't do that - * and just have to keep using the current stack (which is the irq stack already - * after all) - */ - - if (curctx == irqctx) - action_ret = handle_IRQ_event(irq, ®s, action); - else { - /* build the stack frame on the IRQ stack */ - isp = (u32*) ((char*)irqctx + sizeof(*irqctx)); - irqctx->tinfo.task = curctx->tinfo.task; - irqctx->tinfo.previous_esp = current_stack_pointer(); - - *--isp = (u32) action; - *--isp = (u32) ®s; - *--isp = (u32) irq; - - asm volatile( - " xchgl %%ebx,%%esp \n" - " call handle_IRQ_event \n" - " xchgl %%ebx,%%esp \n" - : "=a"(action_ret) - : "b"(isp) - : "memory", "cc", "edx", "ecx" - ); - - - } - spin_lock(&desc->lock); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); - if (curctx != irqctx) - irqctx->tinfo.task = NULL; - if (likely(!(desc->status & IRQ_PENDING))) - break; - desc->status &= ~IRQ_PENDING; - } - -#else - - for (;;) { - irqreturn_t action_ret; - - spin_unlock(&desc->lock); + if (curctx != irqctx) { + /* build the stack frame on the IRQ stack */ + isp = (u32*) ((char*)irqctx + sizeof(*irqctx)); + irqctx->tinfo.task = curctx->tinfo.task; + irqctx->tinfo.previous_esp = current_stack_pointer(); - action_ret = handle_IRQ_event(irq, ®s, action); + *--isp = (u32) ®s; + *--isp = (u32) irq; - spin_lock(&desc->lock); - if (!noirqdebug) - note_interrupt(irq, desc, action_ret); - if (likely(!(desc->status & IRQ_PENDING))) - break; - desc->status &= ~IRQ_PENDING; - } + asm volatile( + " xchgl %%ebx,%%esp \n" + " call __do_IRQ \n" + " xchgl %%ebx,%%esp \n" + : : "b"(isp) + : "memory", "cc", "eax", "edx", "ecx" + ); + } else #endif - desc->status &= ~IRQ_INPROGRESS; - -out: - /* - * The ->end() handler has to deal with interrupts which got - * disabled while the handler was running. - */ - desc->handler->end(irq); - spin_unlock(&desc->lock); + __do_IRQ(irq, ®s); irq_exit(); return 1; } -int can_request_irq(unsigned int irq, unsigned long irqflags) -{ - struct irqaction *action; - - if (irq >= NR_IRQS) - return 0; - action = irq_desc[irq].action; - if (action) { - if (irqflags & action->flags & SA_SHIRQ) - action = NULL; - } - return !action; -} - -/** - * request_irq - allocate an interrupt line - * @irq: Interrupt line to allocate - * @handler: Function to be called when the IRQ occurs - * @irqflags: Interrupt type flags - * @devname: An ascii name for the claiming device - * @dev_id: A cookie passed back to the handler function - * - * This call allocates interrupt resources and enables the - * interrupt line and IRQ handling. From the point this - * call is made your handler function may be invoked. Since - * your handler function must clear any interrupt the board - * raises, you must take care both to initialise your hardware - * and to set up the interrupt handler in the right order. - * - * Dev_id must be globally unique. Normally the address of the - * device data structure is used as the cookie. Since the handler - * receives this value it makes sense to use it. - * - * If your interrupt is shared you must pass a non NULL dev_id - * as this is required when freeing the interrupt. - * - * Flags: - * - * SA_SHIRQ Interrupt is shared - * - * SA_INTERRUPT Disable local interrupts while processing - * - * SA_SAMPLE_RANDOM The interrupt can be used for entropy - * - */ - -int request_irq(unsigned int irq, - irqreturn_t (*handler)(int, void *, struct pt_regs *), - unsigned long irqflags, - const char * devname, - void *dev_id) -{ - int retval; - struct irqaction * action; - -#if 1 - /* - * Sanity-check: shared interrupts should REALLY pass in - * a real dev-ID, otherwise we'll have trouble later trying - * to figure out which interrupt is which (messes up the - * interrupt freeing logic etc). - */ - if (irqflags & SA_SHIRQ) { - if (!dev_id) - printk("Bad boy: %s (at 0x%x) called us without a dev_id!\n", devname, (&irq)[-1]); - } -#endif - - if (irq >= NR_IRQS) - return -EINVAL; - if (!handler) - return -EINVAL; - - action = (struct irqaction *) - kmalloc(sizeof(struct irqaction), GFP_ATOMIC); - if (!action) - return -ENOMEM; - - action->handler = handler; - action->flags = irqflags; - cpus_clear(action->mask); - action->name = devname; - action->next = NULL; - action->dev_id = dev_id; - - retval = setup_irq(irq, action); - if (retval) - kfree(action); - return retval; -} - -EXPORT_SYMBOL(request_irq); - -/** - * free_irq - free an interrupt - * @irq: Interrupt line to free - * @dev_id: Device identity to free - * - * Remove an interrupt handler. The handler is removed and if the - * interrupt line is no longer in use by any driver it is disabled. - * On a shared IRQ the caller must ensure the interrupt is disabled - * on the card it drives before calling this function. The function - * does not return until any executing interrupts for this IRQ - * have completed. - * - * This function must not be called from interrupt context. - */ - -void free_irq(unsigned int irq, void *dev_id) -{ - irq_desc_t *desc; - struct irqaction **p; - unsigned long flags; - - if (irq >= NR_IRQS) - return; - - desc = irq_desc + irq; - spin_lock_irqsave(&desc->lock,flags); - p = &desc->action; - for (;;) { - struct irqaction * action = *p; - if (action) { - struct irqaction **pp = p; - p = &action->next; - if (action->dev_id != dev_id) - continue; - - /* Found it - now remove it from the list of entries */ - *pp = action->next; - if (!desc->action) { - desc->status |= IRQ_DISABLED; - desc->handler->shutdown(irq); - } - spin_unlock_irqrestore(&desc->lock,flags); - - /* Wait to make sure it's not being used on another CPU */ - synchronize_irq(irq); - kfree(action); - return; - } - printk("Trying to free free IRQ%d\n",irq); - spin_unlock_irqrestore(&desc->lock,flags); - return; - } -} - -EXPORT_SYMBOL(free_irq); - -/* - * IRQ autodetection code.. - * - * This depends on the fact that any interrupt that - * comes in on to an unassigned handler will get stuck - * with "IRQ_WAITING" cleared and the interrupt - * disabled. - */ - -static DECLARE_MUTEX(probe_sem); - -/** - * probe_irq_on - begin an interrupt autodetect - * - * Commence probing for an interrupt. The interrupts are scanned - * and a mask of potential interrupt lines is returned. - * - */ - -unsigned long probe_irq_on(void) -{ - unsigned int i; - irq_desc_t *desc; - unsigned long val; - unsigned long delay; - - down(&probe_sem); - /* - * something may have generated an irq long ago and we want to - * flush such a longstanding irq before considering it as spurious. - */ - for (i = NR_IRQS-1; i > 0; i--) { - desc = irq_desc + i; - - spin_lock_irq(&desc->lock); - if (!irq_desc[i].action) - irq_desc[i].handler->startup(i); - spin_unlock_irq(&desc->lock); - } - - /* Wait for longstanding interrupts to trigger. */ - for (delay = jiffies + HZ/50; time_after(delay, jiffies); ) - /* about 20ms delay */ barrier(); - - /* - * enable any unassigned irqs - * (we must startup again here because if a longstanding irq - * happened in the previous stage, it may have masked itself) - */ - for (i = NR_IRQS-1; i > 0; i--) { - desc = irq_desc + i; - - spin_lock_irq(&desc->lock); - if (!desc->action) { - desc->status |= IRQ_AUTODETECT | IRQ_WAITING; - if (desc->handler->startup(i)) - desc->status |= IRQ_PENDING; - } - spin_unlock_irq(&desc->lock); - } - - /* - * Wait for spurious interrupts to trigger - */ - for (delay = jiffies + HZ/10; time_after(delay, jiffies); ) - /* about 100ms delay */ barrier(); - - /* - * Now filter out any obviously spurious interrupts - */ - val = 0; - for (i = 0; i < NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - /* It triggered already - consider it spurious. */ - if (!(status & IRQ_WAITING)) { - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } else - if (i < 32) - val |= 1 << i; - } - spin_unlock_irq(&desc->lock); - } - - return val; -} - -EXPORT_SYMBOL(probe_irq_on); - -/* - * Return a mask of triggered interrupts (this - * can handle only legacy ISA interrupts). - */ - -/** - * probe_irq_mask - scan a bitmap of interrupt lines - * @val: mask of interrupts to consider - * - * Scan the ISA bus interrupt lines and return a bitmap of - * active interrupts. The interrupt probe logic state is then - * returned to its previous value. - * - * Note: we need to scan all the irq's even though we will - * only return ISA irq numbers - just so that we reset them - * all to a known state. - */ -unsigned int probe_irq_mask(unsigned long val) -{ - int i; - unsigned int mask; - - mask = 0; - for (i = 0; i < NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - if (i < 16 && !(status & IRQ_WAITING)) - mask |= 1 << i; - - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } - spin_unlock_irq(&desc->lock); - } - up(&probe_sem); - - return mask & val; -} - -/* - * Return the one interrupt that triggered (this can - * handle any interrupt source). - */ - -/** - * probe_irq_off - end an interrupt autodetect - * @val: mask of potential interrupts (unused) - * - * Scans the unused interrupt lines and returns the line which - * appears to have triggered the interrupt. If no interrupt was - * found then zero is returned. If more than one interrupt is - * found then minus the first candidate is returned to indicate - * their is doubt. - * - * The interrupt probe logic state is returned to its previous - * value. - * - * BUGS: When used in a module (which arguably shouldnt happen) - * nothing prevents two IRQ probe callers from overlapping. The - * results of this are non-optimal. - */ - -int probe_irq_off(unsigned long val) -{ - int i, irq_found, nr_irqs; - - nr_irqs = 0; - irq_found = 0; - for (i = 0; i < NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - if (!(status & IRQ_WAITING)) { - if (!nr_irqs) - irq_found = i; - nr_irqs++; - } - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } - spin_unlock_irq(&desc->lock); - } - up(&probe_sem); - - if (nr_irqs > 1) - irq_found = -irq_found; - return irq_found; -} - -EXPORT_SYMBOL(probe_irq_off); - -/* this was setup_x86_irq but it seems pretty generic */ -int setup_irq(unsigned int irq, struct irqaction * new) -{ - int shared = 0; - unsigned long flags; - struct irqaction *old, **p; - irq_desc_t *desc = irq_desc + irq; - - if (desc->handler == &no_irq_type) - return -ENOSYS; - /* - * Some drivers like serial.c use request_irq() heavily, - * so we have to be careful not to interfere with a - * running system. - */ - if (new->flags & SA_SAMPLE_RANDOM) { - /* - * This function might sleep, we want to call it first, - * outside of the atomic block. - * Yes, this might clear the entropy pool if the wrong - * driver is attempted to be loaded, without actually - * installing a new handler, but is this really a problem, - * only the sysadmin is able to do this. - */ - rand_initialize_irq(irq); - } - - /* - * The following block of code has to be executed atomically - */ - spin_lock_irqsave(&desc->lock,flags); - p = &desc->action; - if ((old = *p) != NULL) { - /* Can't share interrupts unless both agree to */ - if (!(old->flags & new->flags & SA_SHIRQ)) { - spin_unlock_irqrestore(&desc->lock,flags); - return -EBUSY; - } - - /* add new interrupt at end of irq queue */ - do { - p = &old->next; - old = *p; - } while (old); - shared = 1; - } - - *p = new; - - if (!shared) { - desc->depth = 0; - desc->status &= ~(IRQ_DISABLED | IRQ_AUTODETECT | IRQ_WAITING | IRQ_INPROGRESS); - desc->handler->startup(irq); - } - spin_unlock_irqrestore(&desc->lock,flags); - - register_irq_proc(irq); - return 0; -} - -static struct proc_dir_entry * root_irq_dir; -static struct proc_dir_entry * irq_dir [NR_IRQS]; - -#ifdef CONFIG_SMP - -static struct proc_dir_entry *smp_affinity_entry[NR_IRQS]; - -cpumask_t irq_affinity[NR_IRQS] = { [0 ... NR_IRQS-1] = CPU_MASK_ALL }; - -static int irq_affinity_read_proc(char *page, char **start, off_t off, - int count, int *eof, void *data) -{ - int len = cpumask_scnprintf(page, count, irq_affinity[(long)data]); - if (count - len < 2) - return -EINVAL; - len += sprintf(page + len, "\n"); - return len; -} - -static int irq_affinity_write_proc(struct file *file, const char __user *buffer, - unsigned long count, void *data) -{ - int irq = (long)data, full_count = count, err; - cpumask_t new_value, tmp; - - if (!irq_desc[irq].handler->set_affinity) - return -EIO; - - err = cpumask_parse(buffer, count, new_value); - if (err) - return err; - - /* - * Do not allow disabling IRQs completely - it's a too easy - * way to make the system unusable accidentally :-) At least - * one online CPU still has to be targeted. - */ - cpus_and(tmp, new_value, cpu_online_map); - if (cpus_empty(tmp)) - return -EINVAL; - - irq_affinity[irq] = new_value; - irq_desc[irq].handler->set_affinity(irq, - cpumask_of_cpu(first_cpu(new_value))); - - return full_count; -} - -#endif -#define MAX_NAMELEN 10 - -static void register_irq_proc (unsigned int irq) -{ - char name [MAX_NAMELEN]; - - if (!root_irq_dir || (irq_desc[irq].handler == &no_irq_type) || - irq_dir[irq]) - return; - - memset(name, 0, MAX_NAMELEN); - sprintf(name, "%d", irq); - - /* create /proc/irq/1234 */ - irq_dir[irq] = proc_mkdir(name, root_irq_dir); - -#ifdef CONFIG_SMP - { - struct proc_dir_entry *entry; - - /* create /proc/irq/1234/smp_affinity */ - entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]); - - if (entry) { - entry->nlink = 1; - entry->data = (void *)(long)irq; - entry->read_proc = irq_affinity_read_proc; - entry->write_proc = irq_affinity_write_proc; - } - - smp_affinity_entry[irq] = entry; - } -#endif -} - -void init_irq_proc (void) -{ - int i; - - /* create /proc/irq */ - root_irq_dir = proc_mkdir("irq", NULL); - create_prof_cpu_mask(root_irq_dir); - /* - * Create entries for all existing IRQs. - */ - for (i = 0; i < NR_IRQS; i++) - register_irq_proc(i); -} - - #ifdef CONFIG_4KSTACKS + /* * These should really be __section__(".bss.page_aligned") as well, but * gcc's 3.0 and earlier don't handle that correctly. */ -static char softirq_stack[NR_CPUS * THREAD_SIZE] __attribute__((__aligned__(THREAD_SIZE))); -static char hardirq_stack[NR_CPUS * THREAD_SIZE] __attribute__((__aligned__(THREAD_SIZE))); +static char softirq_stack[NR_CPUS * THREAD_SIZE] + __attribute__((__aligned__(THREAD_SIZE))); + +static char hardirq_stack[NR_CPUS * THREAD_SIZE] + __attribute__((__aligned__(THREAD_SIZE))); /* * allocate per-cpu stacks for hardirq and for softirq processing @@ -1140,7 +162,6 @@ asmlinkage void do_softirq(void) /* build the stack frame on the softirq stack */ isp = (u32*) ((char*)irqctx + sizeof(*irqctx)); - asm volatile( " xchgl %%ebx,%%esp \n" " call __do_softirq \n" @@ -1156,3 +177,74 @@ asmlinkage void do_softirq(void) EXPORT_SYMBOL(do_softirq); #endif + +/* + * Interrupt statistics: + */ + +atomic_t irq_err_count; +#if defined(CONFIG_X86_IO_APIC) && defined(APIC_MISMATCH_DEBUG) +atomic_t irq_mis_count; +#endif + +/* + * /proc/interrupts printing: + */ + +int show_interrupts(struct seq_file *p, void *v) +{ + int i = *(loff_t *) v, j; + struct irqaction * action; + unsigned long flags; + + if (i == 0) { + seq_printf(p, " "); + for (j=0; jtypename); + seq_printf(p, " %s", action->name); + + for (action=action->next; action; action = action->next) + seq_printf(p, ", %s", action->name); + + seq_putc(p, '\n'); +skip: + spin_unlock_irqrestore(&irq_desc[i].lock, flags); + } else if (i == NR_IRQS) { + seq_printf(p, "NMI: "); + for (j = 0; j < NR_CPUS; j++) + if (cpu_online(j)) + seq_printf(p, "%10u ", nmi_count(j)); + seq_putc(p, '\n'); +#ifdef CONFIG_X86_LOCAL_APIC + seq_printf(p, "LOC: "); + for (j = 0; j < NR_CPUS; j++) + if (cpu_online(j)) + seq_printf(p, "%10u ", + irq_stat[j].apic_timer_irqs); + seq_putc(p, '\n'); +#endif + seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); +#if defined(CONFIG_X86_IO_APIC) && defined(APIC_MISMATCH_DEBUG) + seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count)); +#endif + } + return 0; +} diff -puN arch/i386/kernel/process.c~generic-irq-subsystem-x86-port arch/i386/kernel/process.c --- 25/arch/i386/kernel/process.c~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/arch/i386/kernel/process.c Fri Oct 1 14:25:52 2004 @@ -344,7 +344,7 @@ void release_thread(struct task_struct * } } - release_x86_irqs(dead_task); + release_vm86_irqs(dead_task); } /* diff -puN arch/i386/kernel/vm86.c~generic-irq-subsystem-x86-port arch/i386/kernel/vm86.c --- 25/arch/i386/kernel/vm86.c~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/arch/i386/kernel/vm86.c Fri Oct 1 14:25:52 2004 @@ -741,7 +741,7 @@ static inline void free_vm86_irq(int irq spin_unlock_irqrestore(&irqbits_lock, flags); } -void release_x86_irqs(struct task_struct *task) +void release_vm86_irqs(struct task_struct *task) { int i; for (i = FIRST_VM86_IRQ ; i <= LAST_VM86_IRQ; i++) diff -puN include/asm-i386/hardirq.h~generic-irq-subsystem-x86-port include/asm-i386/hardirq.h --- 25/include/asm-i386/hardirq.h~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/include/asm-i386/hardirq.h Fri Oct 1 14:25:52 2004 @@ -15,47 +15,25 @@ typedef struct { #include /* Standard mappings for irq_cpustat_t above */ /* - * We put the hardirq and softirq counter into the preemption - * counter. The bitmask has the following meaning: - * - * - bits 0-7 are the preemption count (max preemption depth: 256) - * - bits 8-15 are the softirq count (max # of softirqs: 256) - * - bits 16-23 are the hardirq count (max # of hardirqs: 256) - * - * - ( bit 26 is the PREEMPT_ACTIVE flag. ) - * - * PREEMPT_MASK: 0x000000ff - * SOFTIRQ_MASK: 0x0000ff00 - * HARDIRQ_MASK: 0x00ff0000 + * 'what should we do if we get a hw irq event on an illegal vector'. + * each architecture has to answer this themselves. */ - -#define PREEMPT_BITS 8 -#define SOFTIRQ_BITS 8 -#define HARDIRQ_BITS 8 - -#define PREEMPT_SHIFT 0 -#define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS) -#define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS) - -/* - * The hardirq mask has to be large enough to have - * space for potentially all IRQ sources in the system - * nesting on a single CPU: - */ -#if (1 << HARDIRQ_BITS) < NR_IRQS -# error HARDIRQ_BITS is too low! +static inline void ack_bad_irq(unsigned int irq) +{ +#ifdef CONFIG_X86 + printk("unexpected IRQ trap at vector %02x\n", irq); +#ifdef CONFIG_X86_LOCAL_APIC + /* + * Currently unexpected vectors happen only on SMP and APIC. + * We _must_ ack these because every local APIC has only N + * irq slots per priority level, and a 'hanging, unacked' IRQ + * holds up an irq slot - in excessive cases (when multiple + * unexpected vectors occur) that might lock up the APIC + * completely. + */ + ack_APIC_irq(); #endif - -#define nmi_enter() (irq_enter()) -#define nmi_exit() (preempt_count() -= HARDIRQ_OFFSET) - -#define irq_enter() (preempt_count() += HARDIRQ_OFFSET) -#define irq_exit() \ -do { \ - preempt_count() -= IRQ_EXIT_OFFSET; \ - if (!in_interrupt() && softirq_pending(smp_processor_id())) \ - do_softirq(); \ - preempt_enable_no_resched(); \ -} while (0) +#endif +} #endif /* __ASM_HARDIRQ_H */ diff -puN include/asm-i386/hw_irq.h~generic-irq-subsystem-x86-port include/asm-i386/hw_irq.h --- 25/include/asm-i386/hw_irq.h~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/include/asm-i386/hw_irq.h Fri Oct 1 14:25:52 2004 @@ -45,8 +45,6 @@ asmlinkage void thermal_interrupt(struct #define platform_legacy_irq(irq) ((irq) < 16) #endif -void mask_irq(unsigned int irq); -void unmask_irq(unsigned int irq); void disable_8259A_irq(unsigned int irq); void enable_8259A_irq(unsigned int irq); int i8259A_irq_pending(unsigned int irq); diff -puN include/asm-i386/irq.h~generic-irq-subsystem-x86-port include/asm-i386/irq.h --- 25/include/asm-i386/irq.h~generic-irq-subsystem-x86-port Fri Oct 1 14:25:52 2004 +++ 25-akpm/include/asm-i386/irq.h Fri Oct 1 14:25:52 2004 @@ -21,38 +21,17 @@ static __inline__ int irq_canonicalize(i return ((irq == 2) ? 9 : irq); } -extern void disable_irq(unsigned int); -extern void disable_irq_nosync(unsigned int); -extern void enable_irq(unsigned int); -extern void release_x86_irqs(struct task_struct *); -extern int can_request_irq(unsigned int, unsigned long flags); +extern void release_vm86_irqs(struct task_struct *); #ifdef CONFIG_X86_LOCAL_APIC -#define ARCH_HAS_NMI_WATCHDOG /* See include/linux/nmi.h */ +# define ARCH_HAS_NMI_WATCHDOG /* See include/linux/nmi.h */ #endif #ifdef CONFIG_4KSTACKS -/* - * per-CPU IRQ handling contexts (thread information and stack) - */ -union irq_ctx { - struct thread_info tinfo; - u32 stack[THREAD_SIZE/sizeof(u32)]; -}; - -extern union irq_ctx *hardirq_ctx[NR_CPUS]; -extern union irq_ctx *softirq_ctx[NR_CPUS]; - -extern void irq_ctx_init(int cpu); - -#define __ARCH_HAS_DO_SOFTIRQ + extern void irq_ctx_init(int cpu); +# define __ARCH_HAS_DO_SOFTIRQ #else -#define irq_ctx_init(cpu) do { ; } while (0) +# define irq_ctx_init(cpu) do { } while (0) #endif -struct irqaction; -struct pt_regs; -asmlinkage int handle_IRQ_event(unsigned int, struct pt_regs *, - struct irqaction *); - #endif /* _ASM_IRQ_H */ _