generic hardirq handling for uml

generic hardirq handling for uml

[Martin Waitz]

[-- Attachment #1: Type: text/plain, Size: 19080 bytes --]

hoi :)

I just ported arch/um to generic hardirq handling.
It works for me on a 2.6.9-rc4-mm1 kernel.

Without this patch, ARCH=um does not build as it tries
to use arch/hardirq.h which is already ported to generic
hardirq on i386.

Signed-off-by: Martin Waitz <tali@admignilde.org>

Index: linux-2.6/arch/um/Kconfig
===================================================================
--- linux-2.6.orig/arch/um/Kconfig	2004-10-17 18:36:05.000000000 +0200
+++ linux-2.6/arch/um/Kconfig	2004-10-17 18:36:19.000000000 +0200
@@ -7,6 +7,13 @@
 	bool
 	default y
 
+#
+# Use the generic interrupt handling code in kernel/irq/:
+#
+config GENERIC_HARDIRQS
+	bool
+	default y
+
 mainmenu "Linux/Usermode Kernel Configuration"
 
 config ISA
Index: linux-2.6/arch/um/kernel/irq.c
===================================================================
--- linux-2.6.orig/arch/um/kernel/irq.c	2004-10-17 18:35:12.000000000 +0200
+++ linux-2.6/arch/um/kernel/irq.c	2004-10-20 00:36:08.000000000 +0200
@@ -5,89 +5,64 @@
  *	Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
  */
 
-#include "linux/config.h"
 #include "linux/kernel.h"
 #include "linux/module.h"
 #include "linux/smp.h"
 #include "linux/irq.h"
 #include "linux/kernel_stat.h"
 #include "linux/interrupt.h"
-#include "linux/random.h"
-#include "linux/slab.h"
 #include "linux/file.h"
-#include "linux/proc_fs.h"
 #include "linux/init.h"
 #include "linux/seq_file.h"
 #include "linux/profile.h"
 #include "linux/hardirq.h"
-#include "asm/irq.h"
-#include "asm/hw_irq.h"
-#include "asm/atomic.h"
-#include "asm/signal.h"
-#include "asm/system.h"
-#include "asm/errno.h"
-#include "asm/uaccess.h"
 #include "user_util.h"
 #include "kern_util.h"
 #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
-	}
-};
+void ack_bad_irq(unsigned int irq)
+{
+	printk("unexpected IQ trap at vector %02x\n", irq);
+}
 
 /*
- * Generic no controller code
+ * do_IRQ handles all normal device IRQ's (the special
+ * SMP cross-CPU interrupts have their own specific
+ * handlers).
  */
+unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
+{
+	irq_enter();
+
+	__do_IRQ(irq, (struct pt_regs *) regs);
+
+	irq_exit();
+
+	return 1;
+}
+
 
-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)
+int um_request_irq(unsigned int irq, int fd, int type,
+		   irqreturn_t (*handler)(int, void *, struct pt_regs *),
+		   unsigned long irqflags, const char * devname,
+		   void *dev_id)
 {
-/*
- * '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
+	int err;
+
+	err = request_irq(irq, handler, irqflags, devname, dev_id);
+	if(err)
+		return(err);
+
+	if(fd != -1)
+		err = activate_fd(irq, fd, type, dev_id);
+	return(err);
 }
+EXPORT_SYMBOL(um_request_irq);
+EXPORT_SYMBOL(reactivate_fd);
 
-/* 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:
- */
 
 int show_interrupts(struct seq_file *p, void *v)
 {
@@ -136,530 +111,6 @@
 	return 0;
 }
 
-/*
- * 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
- * SMP cross-CPU interrupts have their own specific
- * handlers).
- */
-unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
-{	
-	/* 
-	 * 0 return value means that this irq is already being
-	 * handled by some other CPU. (or is disabled)
-	 */
-	irq_desc_t *desc = irq_desc + irq;
-	struct irqaction * action;
-	unsigned int status;
-
-	irq_enter();
-	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 (!(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;
-
-	/*
-	 * 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 (!action)
-		goto out;
-
-	/*
-	 * 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.
-	 */
-	for (;;) {
-		spin_unlock(&desc->lock);
-		handle_IRQ_event(irq, (struct pt_regs *) regs, action);
-		spin_lock(&desc->lock);
-		
-		if (!(desc->status & IRQ_PENDING))
-			break;
-		desc->status &= ~IRQ_PENDING;
-	}
-	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);
-
-	irq_exit();
-
-	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 *),
-		   unsigned long irqflags, const char * devname,
-		   void *dev_id)
-{
-	int err;
-
-	err = request_irq(irq, handler, irqflags, devname, dev_id);
-	if(err)
-		return(err);
-
-	if(fd != -1)
-		err = activate_fd(irq, fd, type, dev_id);
-	return(err);
-}
-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)
@@ -675,20 +126,6 @@
 	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)
 {
 	return(0);

-- 
Martin Waitz

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Re: generic hardirq handling for uml

[Chris Wedgwood]

On Wed, Oct 20, 2004 at 02:11:24AM +0200, Martin Waitz wrote:

> I just ported arch/um to generic hardirq handling.

heh, i posted something similat too

> -void free_irq(unsigned int irq, void *dev_id)
[...]
> -			free_irq_by_irq_and_dev(irq, dev_id);

that is actually needed and missing from the generic code, if you run
w/o this you will get funnies won't you?

Re: generic hardirq handling for uml

[Martin Waitz]

[-- Attachment #1: Type: text/plain, Size: 469 bytes --]

hoi :)

On Tue, Oct 19, 2004 at 08:18:26PM -0700, Chris Wedgwood wrote:
> > -void free_irq(unsigned int irq, void *dev_id)
> [...]
> > -			free_irq_by_irq_and_dev(irq, dev_id);

> that is actually needed and missing from the generic code, if you run
> w/o this you will get funnies won't you?

ups, I must have missed that.
Well the system booted but I haven't done stress tests yet.

I guess I'll use your patch for further tests :)

-- 
Martin Waitz

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Re: generic hardirq handling for uml

[Chris Wedgwood]

On Wed, Oct 20, 2004 at 11:46:38AM +0200, Martin Waitz wrote:

> I guess I'll use your patch for further tests :)

it's as clean as it could be yet --- i wanted to make the smallest
diff possible until more of the UML gets merged then i'll do another
pass trimming lots of cruft out

Re: generic hardirq handling for uml

[Andrew Morton]

Martin Waitz <tali@admingilde.org> wrote:
>
> I just ported arch/um to generic hardirq handling.

OK, I'll add this to 2.6.9-mm1 (which appears to be a few days off yet).  If
nobody complains, it goes in.  Thanks.

Re: generic hardirq handling for uml

[Jeff Dike]

tali@admingilde.org said:
> I just ported arch/um to generic hardirq handling. It works for me on
> a 2.6.9-rc4-mm1 kernel. 

Thanks.  I already had most of this in my tree, but you caught a few things
I missed, especially the #include cleanup.  However, the removal of config.h
was a bit much since there are still references to CONFIG_SMP.

				Jeff

Re: generic hardirq handling for uml

[Jeff Dike]

akpm@osdl.org said:
> OK, I'll add this to 2.6.9-mm1 (which appears to be a few days off
> yet).  If nobody complains, it goes in.  Thanks. 

It's pretty good.  I've got it in my tree with a few changes which I'll 
send you when I start dealing with -mm again.

				Jeff

[PATCH] (another!) generic irq handling for UML

[Chris Wedgwood]

On Thu, Oct 21, 2004 at 11:19:50PM -0400, Jeff Dike wrote:

> It's pretty good.  I've got it in my tree with a few changes which
> I'll send you when I start dealing with -mm again.


I ended with the following patch as a compromise for now.  As has been
discussed this entire area needs rewriting at some point but for now I
think this should suffice.


===== arch/um/Kconfig 1.18 vs edited =====
--- 1.18/arch/um/Kconfig	2004-10-13 21:08:32 -07:00
+++ edited/arch/um/Kconfig	2004-10-20 17:47:51 -07:00
@@ -1,3 +1,8 @@
+# UML uses the generic IRQ sugsystem
+config GENERIC_HARDIRQS
+	bool
+	default y
+
 config USERMODE
 	bool
 	default y
===== arch/um/drivers/line.c 1.23 vs edited =====
--- 1.23/arch/um/drivers/line.c	2004-10-21 10:03:21 -07:00
+++ edited/arch/um/drivers/line.c	2004-10-22 13:00:52 -07:00
@@ -110,7 +110,6 @@ static int flush_buffer(struct line *lin
 int line_write(struct line *lines, struct tty_struct *tty, const char *buf, int len)
 {
 	struct line *line;
-	char *new;
 	unsigned long flags;
 	int n, err, i, ret = 0;
 
@@ -143,7 +142,6 @@ int line_write(struct line *lines, struc
 	}
  out_up:
 	up(&line->sem);
- out_free:
 	return(ret);
 }
 
@@ -203,13 +201,17 @@ void line_disable(struct line *line, int
 
 	if(line->driver->read_irq == current_irq)
 		free_irq_later(line->driver->read_irq, line);
-	else
+	else {
+		free_irq_by_irq_and_dev(line->driver->read_irq, line);
 		free_irq(line->driver->read_irq, line);
+	}
 
 	if(line->driver->write_irq == current_irq)
 		free_irq_later(line->driver->write_irq, line);
-	else
+	else {
+		free_irq_by_irq_and_dev(line->driver->write_irq, line);
 		free_irq(line->driver->write_irq, line);
+	}
 
 	line->have_irq = 0;
 }
===== arch/um/drivers/net_kern.c 1.19 vs edited =====
--- 1.19/arch/um/drivers/net_kern.c	2004-09-17 00:07:05 -07:00
+++ edited/arch/um/drivers/net_kern.c	2004-10-22 12:58:05 -07:00
@@ -148,6 +148,7 @@ static int uml_net_close(struct net_devi
 	netif_stop_queue(dev);
 	spin_lock(&lp->lock);
 
+	free_irq_by_irq_and_dev(dev->irq, dev);
 	free_irq(dev->irq, dev);
 	if(lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
 	lp->fd = -1;
===== arch/um/drivers/port_kern.c 1.16 vs edited =====
--- 1.16/arch/um/drivers/port_kern.c	2004-08-24 02:08:18 -07:00
+++ edited/arch/um/drivers/port_kern.c	2004-10-22 12:58:05 -07:00
@@ -242,6 +242,7 @@ int port_wait(void *data)
 		 * connection.  Then we loop here throwing out failed 
 		 * connections until a good one is found.
 		 */
+		free_irq_by_irq_and_dev(TELNETD_IRQ, conn);
 		free_irq(TELNETD_IRQ, conn);
 
 		if(conn->fd >= 0) break;
===== arch/um/drivers/xterm_kern.c 1.5 vs edited =====
--- 1.5/arch/um/drivers/xterm_kern.c	2004-08-24 02:08:18 -07:00
+++ edited/arch/um/drivers/xterm_kern.c	2004-10-22 12:58:05 -07:00
@@ -63,6 +63,7 @@ int xterm_fd(int socket, int *pid_out)
 	}
 	down(&data->sem);
 
+	free_irq_by_irq_and_dev(XTERM_IRQ, data);
 	free_irq(XTERM_IRQ, data);
 
 	ret = data->new_fd;
===== arch/um/include/irq_user.h 1.4 vs edited =====
--- 1.4/arch/um/include/irq_user.h	2004-09-13 17:23:23 -07:00
+++ edited/arch/um/include/irq_user.h	2004-10-20 19:00:29 -07:00
@@ -10,7 +10,7 @@ enum { IRQ_READ, IRQ_WRITE };
 
 extern void sigio_handler(int sig, union uml_pt_regs *regs);
 extern int activate_fd(int irq, int fd, int type, void *dev_id);
-extern void free_irq_by_irq_and_dev(int irq, void *dev_id);
+extern void free_irq_by_irq_and_dev(unsigned int irq, void *dev_id);
 extern void free_irq_by_fd(int fd);
 extern void reactivate_fd(int fd, int irqnum);
 extern void deactivate_fd(int fd, int irqnum);
===== arch/um/kernel/irq.c 1.21 vs edited =====
--- 1.21/arch/um/kernel/irq.c	2004-10-13 21:08:30 -07:00
+++ edited/arch/um/kernel/irq.c	2004-10-22 12:51:49 -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 @@ int show_interrupts(struct seq_file *p, 
 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');
 	}
 
@@ -137,295 +81,18 @@ skip:
 }
 
 /*
- * 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
  * SMP cross-CPU interrupts have their own specific
  * handlers).
  */
 unsigned int do_IRQ(int irq, union uml_pt_regs *regs)
-{	
-	/* 
-	 * 0 return value means that this irq is already being
-	 * handled by some other CPU. (or is disabled)
-	 */
-	irq_desc_t *desc = irq_desc + irq;
-	struct irqaction * action;
-	unsigned int status;
-
-	irq_enter();
-	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 (!(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;
-
-	/*
-	 * 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 (!action)
-		goto out;
-
-	/*
-	 * 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.
-	 */
-	for (;;) {
-		spin_unlock(&desc->lock);
-		handle_IRQ_event(irq, (struct pt_regs *) regs, action);
-		spin_lock(&desc->lock);
-		
-		if (!(desc->status & IRQ_PENDING))
-			break;
-		desc->status &= ~IRQ_PENDING;
-	}
-	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);
-
-	irq_exit();
-
-	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;
+       irq_enter();
+       __do_IRQ(irq, (struct pt_regs *) regs);
+       irq_exit();
+       return 1;
 }
 
-EXPORT_SYMBOL(request_irq);
-
 int um_request_irq(unsigned int irq, int fd, int type,
 		   irqreturn_t (*handler)(int, void *, struct pt_regs *),
 		   unsigned long irqflags, const char * devname,
@@ -444,222 +111,6 @@ int um_request_irq(unsigned int irq, int
 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)
@@ -675,90 +126,27 @@ void irq_unlock(unsigned long flags)
 	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)
-{
-	return(0);
-}
-
-static void shutdown_SIGIO_irq(unsigned int irq)
-{
-}
-
-static void enable_SIGIO_irq(unsigned int irq)
-{
-}
-
-static void disable_SIGIO_irq(unsigned int irq)
-{
-}
-
-static void mask_and_ack_SIGIO(unsigned int irq)
-{
-}
-
-static void end_SIGIO_irq(unsigned int irq)
-{
-}
-
-static unsigned int startup_SIGVTALRM_irq(unsigned int irq)
-{
-	return(0);
-}
-
-static void shutdown_SIGVTALRM_irq(unsigned int irq)
-{
-}
-
-static void enable_SIGVTALRM_irq(unsigned int irq)
-{
-}
-
-static void disable_SIGVTALRM_irq(unsigned int irq)
-{
-}
-
-static void mask_and_ack_SIGVTALRM(unsigned int irq)
-{
-}
-
-static void end_SIGVTALRM_irq(unsigned int irq)
+/*  presently hw_interrupt_type must define (startup || enable) &&
+ *  disable && end */
+static void dummy(unsigned int irq)
 {
 }
 
 static struct hw_interrupt_type SIGIO_irq_type = {
-	"SIGIO",
-	startup_SIGIO_irq,
-	shutdown_SIGIO_irq,
-	enable_SIGIO_irq,
-	disable_SIGIO_irq,
-	mask_and_ack_SIGIO,
-	end_SIGIO_irq,
-	NULL
+	.typename = "SIGIO",
+	.disable = dummy,
+	.enable = dummy,
+	.ack = dummy,
+	.end = dummy
 };
 
 static struct hw_interrupt_type SIGVTALRM_irq_type = {
-	"SIGVTALRM",
-	startup_SIGVTALRM_irq,
-	shutdown_SIGVTALRM_irq,
-	enable_SIGVTALRM_irq,
-	disable_SIGVTALRM_irq,
-	mask_and_ack_SIGVTALRM,
-	end_SIGVTALRM_irq,
-	NULL
+	.typename = "SIGVTALRM",
+	.shutdown = dummy, /* never called */
+	.disable = dummy,
+	.enable = dummy,
+	.ack = dummy,
+	.end = dummy
 };
 
 void __init init_IRQ(void)
===== arch/um/kernel/irq_user.c 1.11 vs edited =====
--- 1.11/arch/um/kernel/irq_user.c	2004-09-13 17:23:23 -07:00
+++ edited/arch/um/kernel/irq_user.c	2004-10-20 19:01:06 -07:00
@@ -263,7 +263,7 @@ static int same_irq_and_dev(struct irq_f
 	return((irq->irq == data->irq) && (irq->id == data->dev));
 }
 
-void free_irq_by_irq_and_dev(int irq, void *dev)
+void free_irq_by_irq_and_dev(unsigned int irq, void *dev)
 {
 	struct irq_and_dev data = ((struct irq_and_dev) { .irq  = irq,
 							  .dev  = dev });
===== arch/um/kernel/process_kern.c 1.23 vs edited =====
--- 1.23/arch/um/kernel/process_kern.c	2004-09-13 17:23:22 -07:00
+++ edited/arch/um/kernel/process_kern.c	2004-10-20 17:47:51 -07:00
@@ -206,7 +206,6 @@ void default_idle(void)
 		 * 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();
 		
===== include/asm-um/hardirq.h 1.1 vs edited =====
--- 1.1/include/asm-um/hardirq.h	2002-09-06 10:29:29 -07:00
+++ edited/include/asm-um/hardirq.h	2004-10-20 17:47:51 -07:00
@@ -1,6 +1,26 @@
-#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 <linux/config.h>
+#include <linux/threads.h>
+#include <linux/irq.h>
+
+/* 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 <linux/irq_cpustat.h>
+
+/* 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();
+}
+
+#endif /* __ASM_UM_HARDIRQ_H */