diff mbox

[RFC,trollpatch,1/1] genirq: Remove the fits all and nothing __do_IRQ() code

Message ID 20100908152036.643594727@linutronix.de (mailing list archive)
State Not Applicable
Headers show

Commit Message

Thomas Gleixner Sept. 8, 2010, 6:14 p.m. UTC
None
diff mbox

Patch

Index: linux-2.6/Documentation/DocBook/genericirq.tmpl
===================================================================
--- linux-2.6.orig/Documentation/DocBook/genericirq.tmpl
+++ linux-2.6/Documentation/DocBook/genericirq.tmpl
@@ -147,13 +147,6 @@ 
 	use a generic irq-flow implementation for 'level type' interrupts
 	and add a (sub)architecture specific 'edge type' implementation.
 	</para>
-	<para>
-	To make the transition to the new model easier and prevent the
-	breakage of existing implementations, the __do_IRQ() super-handler
-	is still available. This leads to a kind of duality for the time
-	being. Over time the new model should be used in more and more
-	architectures, as it enables smaller and cleaner IRQ subsystems.
-	</para>
   </chapter>
   <chapter id="bugs">
     <title>Known Bugs And Assumptions</title>
@@ -402,28 +395,6 @@  desc->chip->end();
     </sect1>
   </chapter>
 
-  <chapter id="doirq">
-     <title>__do_IRQ entry point</title>
-     <para>
- 	The original implementation __do_IRQ() is an alternative entry
-	point for all types of interrupts.
-     </para>
-     <para>
-	This handler turned out to be not suitable for all
-	interrupt hardware and was therefore reimplemented with split
-	functionality for egde/level/simple/percpu interrupts. This is not
-	only a functional optimization. It also shortens code paths for
-	interrupts.
-      </para>
-      <para>
-	To make use of the split implementation, replace the call to
-	__do_IRQ by a call to desc->handle_irq() and associate
-        the appropriate handler function to desc->handle_irq().
-	In most cases the generic handler implementations should
-	be sufficient.
-     </para>
-  </chapter>
-
   <chapter id="locking">
      <title>Locking on SMP</title>
      <para>
Index: linux-2.6/Documentation/feature-removal-schedule.txt
===================================================================
--- linux-2.6.orig/Documentation/feature-removal-schedule.txt
+++ linux-2.6/Documentation/feature-removal-schedule.txt
@@ -315,14 +315,6 @@  Who:	Dave Jones <davej@redhat.com>, Matt
 
 -----------------------------
 
-What:	__do_IRQ all in one fits nothing interrupt handler
-When:	2.6.32
-Why:	__do_IRQ was kept for easy migration to the type flow handlers.
-	More than two years of migration time is enough.
-Who:	Thomas Gleixner <tglx@linutronix.de>
-
------------------------------
-
 What:	fakephp and associated sysfs files in /sys/bus/pci/slots/
 When:	2011
 Why:	In 2.6.27, the semantics of /sys/bus/pci/slots was redefined to
Index: linux-2.6/include/linux/irq.h
===================================================================
--- linux-2.6.orig/include/linux/irq.h
+++ linux-2.6/include/linux/irq.h
@@ -150,7 +150,7 @@  struct irq_2_iommu;
  * @timer_rand_state:	pointer to timer rand state struct
  * @kstat_irqs:		irq stats per cpu
  * @irq_2_iommu:	iommu with this irq
- * @handle_irq:		highlevel irq-events handler [if NULL, __do_IRQ()]
+ * @handle_irq:		highlevel irq-events handler
  * @chip:		low level interrupt hardware access
  * @msi_desc:		MSI descriptor
  * @handler_data:	per-IRQ data for the irq_chip methods
@@ -294,28 +294,12 @@  extern void handle_bad_irq(unsigned int 
 extern void handle_nested_irq(unsigned int irq);
 
 /*
- * Monolithic do_IRQ implementation.
- */
-#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
-extern unsigned int __do_IRQ(unsigned int irq);
-#endif
-
-/*
  * Architectures call this to let the generic IRQ layer
- * handle an interrupt. If the descriptor is attached to an
- * irqchip-style controller then we call the ->handle_irq() handler,
- * and it calls __do_IRQ() if it's attached to an irqtype-style controller.
+ * handle an interrupt.
  */
 static inline void generic_handle_irq_desc(unsigned int irq, struct irq_desc *desc)
 {
-#ifdef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
 	desc->handle_irq(irq, desc);
-#else
-	if (likely(desc->handle_irq))
-		desc->handle_irq(irq, desc);
-	else
-		__do_IRQ(irq);
-#endif
 }
 
 static inline void generic_handle_irq(unsigned int irq)
Index: linux-2.6/kernel/irq/handle.c
===================================================================
--- linux-2.6.orig/kernel/irq/handle.c
+++ linux-2.6/kernel/irq/handle.c
@@ -426,117 +426,6 @@  irqreturn_t handle_IRQ_event(unsigned in
 	return retval;
 }
 
-#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
-
-#ifdef CONFIG_ENABLE_WARN_DEPRECATED
-# warning __do_IRQ is deprecated. Please convert to proper flow handlers
-#endif
-
-/**
- * __do_IRQ - original all in one highlevel IRQ handler
- * @irq:	the interrupt number
- *
- * __do_IRQ handles all normal device IRQ's (the special
- * SMP cross-CPU interrupts have their own specific
- * handlers).
- *
- * This is the original x86 implementation which is used for every
- * interrupt type.
- */
-unsigned int __do_IRQ(unsigned int irq)
-{
-	struct irq_desc *desc = irq_to_desc(irq);
-	struct irqaction *action;
-	unsigned int status;
-
-	kstat_incr_irqs_this_cpu(irq, desc);
-
-	if (CHECK_IRQ_PER_CPU(desc->status)) {
-		irqreturn_t action_ret;
-
-		/*
-		 * No locking required for CPU-local interrupts:
-		 */
-		if (desc->chip->ack)
-			desc->chip->ack(irq);
-		if (likely(!(desc->status & IRQ_DISABLED))) {
-			action_ret = handle_IRQ_event(irq, desc->action);
-			if (!noirqdebug)
-				note_interrupt(irq, desc, action_ret);
-		}
-		desc->chip->end(irq);
-		return 1;
-	}
-
-	raw_spin_lock(&desc->lock);
-	if (desc->chip->ack)
-		desc->chip->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;
-
-	/*
-	 * 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;
-
-	/*
-	 * 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 (;;) {
-		irqreturn_t action_ret;
-
-		raw_spin_unlock(&desc->lock);
-
-		action_ret = handle_IRQ_event(irq, action);
-		if (!noirqdebug)
-			note_interrupt(irq, desc, action_ret);
-
-		raw_spin_lock(&desc->lock);
-		if (likely(!(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->chip->end(irq);
-	raw_spin_unlock(&desc->lock);
-
-	return 1;
-}
-#endif
-
 void early_init_irq_lock_class(void)
 {
 	struct irq_desc *desc;