Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270417AbUJTDPu (ORCPT ); Tue, 19 Oct 2004 23:15:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270385AbUJTDPJ (ORCPT ); Tue, 19 Oct 2004 23:15:09 -0400 Received: from pimout1-ext.prodigy.net ([207.115.63.77]:57548 "EHLO pimout1-ext.prodigy.net") by vger.kernel.org with ESMTP id S270342AbUJTCkD (ORCPT ); Tue, 19 Oct 2004 22:40:03 -0400 Date: Tue, 19 Oct 2004 19:39:44 -0700 To: LKML Cc: Jeff Dike Subject: [PATCH] UML: use the generic irq code Message-ID: <20041020023944.GH8597@taniwha.stupidest.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline From: cw@f00f.org (Chris Wedgwood) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 16344 Lines: 620 UML should use the generic irq code and not the IRQ cruft on the underlying architecture. Strictly speaking to work correctly this requires a previous patch I posted adding the platform_free_irq_notify hook wart. Signed-off-by: cw@f00f.org arch/um/Kconfig | 5 arch/um/kernel/irq.c | 488 ------------------------------------------ arch/um/kernel/process_kern.c | 1 include/asm-um/hardirq.h | 32 ++ 4 files changed, 33 insertions(+), 493 deletions(-) diff -Nru a/arch/um/Kconfig b/arch/um/Kconfig --- a/arch/um/Kconfig 2004-10-19 17:47:47 -07:00 +++ b/arch/um/Kconfig 2004-10-19 17:47:47 -07:00 @@ -1,3 +1,8 @@ +# UML uses the generic IRQ sugsystem +config GENERIC_HARDIRQS + bool + default y + config USERMODE bool default y diff -Nru a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c --- a/arch/um/kernel/irq.c 2004-10-19 17:47:47 -07:00 +++ b/arch/um/kernel/irq.c 2004-10-19 17:47:47 -07:00 @@ -32,58 +32,6 @@ #include "irq_user.h" #include "irq_kern.h" -static void register_irq_proc (unsigned int irq); - -irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned = { - [0 ... NR_IRQS-1] = { - .handler = &no_irq_type, - .lock = SPIN_LOCK_UNLOCKED - } -}; - -/* - * Generic no controller code - */ - -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(KERN_ERR "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 -}; /* * Generic, controller-independent functions: @@ -126,10 +74,6 @@ 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'); } @@ -137,134 +81,11 @@ } /* - * 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. - */ -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; -} - -/* * 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 of an interrupt - * stack. 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); -} - -#ifdef CONFIG_SMP -inline void synchronize_irq(unsigned int irq) -{ - /* is there anything to synchronize with? */ - if (!irq_desc[irq].action) - return; - - while (irq_desc[irq].status & IRQ_INPROGRESS) - cpu_relax(); -} -#endif - -/** - * disable_irq - disable an irq and wait for completion - * @irq: Interrupt to disable - * - * Disable the selected interrupt line. Disables of an interrupt - * stack. That is for two disables you need two enables. 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) -{ - disable_irq_nosync(irq); - synchronize_irq(irq); -} - -/** - * enable_irq - enable interrupt handling on an irq - * @irq: Interrupt to enable - * - * Re-enables the processing of interrupts on this IRQ line - * providing no disable_irq calls are now in effect. - * - * 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(KERN_ERR "enable_irq() unbalanced from %p\n", - __builtin_return_address(0)); - } - spin_unlock_irqrestore(&desc->lock, flags); -} /* * do_IRQ handles all normal device IRQ's (the special @@ -346,85 +167,6 @@ return 1; } -/** - * 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(KERN_ERR "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_KERNEL); - 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); int um_request_irq(unsigned int irq, int fd, int type, irqreturn_t (*handler)(int, void *, struct pt_regs *), @@ -444,222 +186,6 @@ EXPORT_SYMBOL(um_request_irq); EXPORT_SYMBOL(reactivate_fd); -/* 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; - - /* - * 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; - old = *p; - if (old != 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; - desc->handler->startup(irq); - } - spin_unlock_irqrestore(&desc->lock,flags); - - register_irq_proc(irq); - return 0; -} - -/** - * 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 may be called from interrupt context. - * - * Bugs: Attempting to free an irq in a handler for the same irq hangs - * the machine. - */ - -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); - } - free_irq_by_irq_and_dev(irq, dev_id); - 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(KERN_ERR "Trying to free free IRQ%d\n",irq); - spin_unlock_irqrestore(&desc->lock,flags); - return; - } -} - -EXPORT_SYMBOL(free_irq); - -/* These are initialized by sysctl_init, which is called from init/main.c */ -static struct proc_dir_entry * root_irq_dir; -static struct proc_dir_entry * irq_dir [NR_IRQS]; -static struct proc_dir_entry * smp_affinity_entry [NR_IRQS]; - -/* These are read and written as longs, so a read won't see a partial write - * even during a race. - */ -static 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 *buffer, - unsigned long count, void *data) -{ - int irq = (long) data, full_count = count, err; - cpumask_t new_value; - - if (!irq_desc[irq].handler->set_affinity) - return -EIO; - - err = cpumask_parse(buffer, count, new_value); - if(err) - return(err); - -#ifdef CONFIG_SMP - /* - * 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. - */ - { cpumask_t tmp; - cpus_and(tmp, new_value, cpu_online_map); - if (cpus_empty(tmp)) - return -EINVAL; - } -#endif - - irq_affinity[irq] = new_value; - irq_desc[irq].handler->set_affinity(irq, new_value); - - return full_count; -} - -#define MAX_NAMELEN 10 - -static void register_irq_proc (unsigned int irq) -{ - struct proc_dir_entry *entry; - 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); - - /* create /proc/irq/1234/smp_affinity */ - entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]); - - 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; -} - -void __init init_irq_proc (void) -{ - int i; - - /* create /proc/irq */ - root_irq_dir = proc_mkdir("irq", 0); - - /* create /proc/irq/prof_cpu_mask */ - create_prof_cpu_mask(root_irq_dir); - - /* - * Create entries for all existing IRQs. - */ - for (i = 0; i < NR_IRQS; i++) - register_irq_proc(i); -} - static spinlock_t irq_spinlock = SPIN_LOCK_UNLOCKED; unsigned long irq_lock(void) @@ -674,20 +200,6 @@ { spin_unlock_irqrestore(&irq_spinlock, flags); } - -unsigned long probe_irq_on(void) -{ - return(0); -} - -EXPORT_SYMBOL(probe_irq_on); - -int probe_irq_off(unsigned long val) -{ - return(0); -} - -EXPORT_SYMBOL(probe_irq_off); static unsigned int startup_SIGIO_irq(unsigned int irq) { diff -Nru a/arch/um/kernel/process_kern.c b/arch/um/kernel/process_kern.c --- a/arch/um/kernel/process_kern.c 2004-10-19 17:47:47 -07:00 +++ b/arch/um/kernel/process_kern.c 2004-10-19 17:47:47 -07:00 @@ -206,7 +206,6 @@ * although we are an idle CPU, we do not want to * get into the scheduler unnecessarily. */ - irq_stat[smp_processor_id()].idle_timestamp = jiffies; if(need_resched()) schedule(); diff -Nru a/include/asm-um/hardirq.h b/include/asm-um/hardirq.h --- a/include/asm-um/hardirq.h 2004-10-19 17:47:47 -07:00 +++ b/include/asm-um/hardirq.h 2004-10-19 17:47:47 -07:00 @@ -1,6 +1,30 @@ -#ifndef __UM_HARDIRQ_H -#define __UM_HARDIRQ_H +/* (c) 2004 cw@f00f.org, GPLv2 blah blah */ -#include "asm/arch/hardirq.h" +#ifndef __ASM_UM_HARDIRQ_H +#define __ASM_UM_HARDIRQ_H -#endif +#include +#include +#include + +/* NOTE: When SMP works again we might want to make this + * ____cacheline_aligned or maybe use per_cpu state? --cw */ +typedef struct { + unsigned int __softirq_pending; +} irq_cpustat_t; + +#include + +/* As this would be very strange for UML to get we BUG() after the + * printk. */ +static inline void ack_bad_irq(unsigned int irq) +{ + printk(KERN_ERR "unexpected IRQ %02x\n", irq); + BUG(); +} + +void free_irq_by_irq_and_dev(int, void *); + +#define platform_free_irq_notify(i, d) free_irq_by_irq_and_dev(i, d) + +#endif /* __ASM_UM_HARDIRQ_H */ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/