--- /dev/null
+From: Bernhard Walle <bwalle@suse.de>
+Subject: [PATCH] Fix performance regression on large IA64 systems
+References: bnc #469589
+
+This patch tries to address a performance regression discovered by SGI.
+
+Patch b60c1f6ffd88850079ae419aa933ab0eddbd5535 removes the call
+to note_interrupt() in __do_IRQ(). Patch d85a60d85ea5b7c597508c1510c88e657773d378
+adds it again. Because it's needed for irqpoll.
+
+That patch now introduces a new parameter 'only_fixup' for note_interrupt().
+This parameter determines two cases:
+
+ TRUE => The function should be only executed when irqfixup is set.
+ Either 'irqpoll' or 'irqfixup' directly set that.
+
+ FALSE => Just the behaviour as note_interrupt() always had.
+
+Now the patch converts all calls of note_interrupt() to only_fixup=FALSE,
+except the call that has been removed by b60c1f6ffd88850079ae419aa933ab0eddbd5535.
+So that call is always done, but the body is only executed when either
+'irqpoll' or 'irqfixup' are specified.
+
+This patch is not meant for mainline inclusion in the first run!
+
+
+Signed-off-by: Bernhard Walle <bwalle@suse.de>
+
+---
+ arch/arm/mach-ns9xxx/irq.c | 2 +-
+ arch/powerpc/platforms/cell/interrupt.c | 2 +-
+ include/linux/irq.h | 2 +-
+ kernel/irq/chip.c | 10 +++++-----
+ kernel/irq/handle.c | 4 ++--
+ kernel/irq/spurious.c | 13 ++++++++++++-
+ 6 files changed, 22 insertions(+), 11 deletions(-)
+
+--- a/arch/arm/mach-ns9xxx/irq.c
++++ b/arch/arm/mach-ns9xxx/irq.c
+@@ -86,7 +86,7 @@ static void handle_prio_irq(unsigned int
+ /* XXX: There is no direct way to access noirqdebug, so check
+ * unconditionally for spurious irqs...
+ * Maybe this function should go to kernel/irq/chip.c? */
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 0);
+
+ spin_lock(&desc->lock);
+ desc->status &= ~IRQ_INPROGRESS;
+--- a/arch/powerpc/platforms/cell/interrupt.c
++++ b/arch/powerpc/platforms/cell/interrupt.c
+@@ -270,7 +270,7 @@ static void handle_iic_irq(unsigned int
+ spin_unlock(&desc->lock);
+ action_ret = handle_IRQ_event(irq, action);
+ if (!noirqdebug)
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 0);
+ spin_lock(&desc->lock);
+
+ } while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING);
+--- a/include/linux/irq.h
++++ b/include/linux/irq.h
+@@ -296,7 +296,7 @@ static inline void generic_handle_irq(un
+
+ /* Handling of unhandled and spurious interrupts: */
+ extern void note_interrupt(unsigned int irq, struct irq_desc *desc,
+- int action_ret);
++ int action_ret, int only_fixup);
+
+ /* Resending of interrupts :*/
+ void check_irq_resend(struct irq_desc *desc, unsigned int irq);
+--- a/kernel/irq/chip.c
++++ b/kernel/irq/chip.c
+@@ -324,7 +324,7 @@ handle_simple_irq(unsigned int irq, stru
+
+ action_ret = handle_IRQ_event(irq, action);
+ if (!noirqdebug)
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 0);
+
+ spin_lock(&desc->lock);
+ desc->status &= ~IRQ_INPROGRESS;
+@@ -370,7 +370,7 @@ handle_level_irq(unsigned int irq, struc
+
+ action_ret = handle_IRQ_event(irq, action);
+ if (!noirqdebug)
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 0);
+
+ spin_lock(&desc->lock);
+ desc->status &= ~IRQ_INPROGRESS;
+@@ -423,7 +423,7 @@ handle_fasteoi_irq(unsigned int irq, str
+
+ action_ret = handle_IRQ_event(irq, action);
+ if (!noirqdebug)
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 0);
+
+ spin_lock(&desc->lock);
+ desc->status &= ~IRQ_INPROGRESS;
+@@ -503,7 +503,7 @@ handle_edge_irq(unsigned int irq, struct
+ spin_unlock(&desc->lock);
+ action_ret = handle_IRQ_event(irq, action);
+ if (!noirqdebug)
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 0);
+ spin_lock(&desc->lock);
+
+ } while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING);
+@@ -532,7 +532,7 @@ handle_percpu_irq(unsigned int irq, stru
+
+ action_ret = handle_IRQ_event(irq, desc->action);
+ if (!noirqdebug)
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 0);
+
+ if (desc->chip->eoi)
+ desc->chip->eoi(irq);
+--- a/kernel/irq/handle.c
++++ b/kernel/irq/handle.c
+@@ -187,7 +187,7 @@ unsigned int __do_IRQ(unsigned int irq)
+ if (likely(!(desc->status & IRQ_DISABLED))) {
+ action_ret = handle_IRQ_event(irq, desc->action);
+ if (!noirqdebug)
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 1);
+ }
+ desc->chip->end(irq);
+ return 1;
+@@ -241,7 +241,7 @@ unsigned int __do_IRQ(unsigned int irq)
+
+ action_ret = handle_IRQ_event(irq, action);
+ if (!noirqdebug)
+- note_interrupt(irq, desc, action_ret);
++ note_interrupt(irq, desc, action_ret, 0);
+
+ spin_lock(&desc->lock);
+ if (likely(!(desc->status & IRQ_PENDING)))
+--- a/kernel/irq/spurious.c
++++ b/kernel/irq/spurious.c
+@@ -171,8 +171,19 @@ static inline int try_misrouted_irq(unsi
+ }
+
+ void note_interrupt(unsigned int irq, struct irq_desc *desc,
+- irqreturn_t action_ret)
++ irqreturn_t action_ret, int only_fixup)
+ {
++ /*
++ * The parameter "only_fixup" means that the function should be only
++ * executed if this parameter is set to 1 and the function should
++ * not be executed if the parameter is 0.
++ *
++ * We need that because irqfixup is static to the function but
++ * this function is called from kernel/irq/handle.c.
++ */
++ if (only_fixup && irqfixup == 0)
++ return;
++
+ if (unlikely(action_ret != IRQ_HANDLED)) {
+ /*
+ * If we are seeing only the odd spurious IRQ caused by
projects / people / pmueller / ipfire-2.x.git / blobdiff