IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

49 files changed, 165 insertions, 122 deletions

diff --git a/include/asm-frv/dma.h b/include/asm-frv/dma.h
index 18d6bb8f84f..683c47d48a5 100644
--- a/include/asm-frv/dma.h
+++ b/include/asm-frv/dma.h
@@ -24,10 +24,7 @@
 /*
  * FRV DMA controller management
  */
-struct pt_regs;
-
-typedef irqreturn_t (*dma_irq_handler_t)(int dmachan, unsigned long cstr, void *data,
-					 struct pt_regs *regs);
+typedef irqreturn_t (*dma_irq_handler_t)(int dmachan, unsigned long cstr, void *data);
 
 extern void frv_dma_init(void);
 
diff --git a/include/asm-frv/irq_regs.h b/include/asm-frv/irq_regs.h
new file mode 100644
index 00000000000..d22e83289ad
--- /dev/null
+++ b/include/asm-frv/irq_regs.h
@@ -0,0 +1,27 @@
+/* FRV per-CPU frame pointer holder
+ *
+ * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _ASM_IRQ_REGS_H
+#define _ASM_IRQ_REGS_H
+
+/*
+ * Per-cpu current frame pointer - the location of the last exception frame on
+ * the stack
+ * - on FRV, GR28 is dedicated to keeping a pointer to the current exception
+ *   frame
+ */
+#define ARCH_HAS_OWN_IRQ_REGS
+
+#ifndef __ASSEMBLY__
+#define get_irq_regs() (__frame)
+#endif
+
+#endif /* _ASM_IRQ_REGS_H */
diff --git a/include/asm-frv/ptrace.h b/include/asm-frv/ptrace.h
index 7ff525162a7..9a2241b8eb1 100644
--- a/include/asm-frv/ptrace.h
+++ b/include/asm-frv/ptrace.h
@@ -12,6 +12,7 @@
 #define _ASM_PTRACE_H
 
 #include <asm/registers.h>
+#include <asm/irq_regs.h>
 
 #define in_syscall(regs) (((regs)->tbr & TBR_TT) == TBR_TT_TRAP0)
 
diff --git a/include/asm-generic/irq_regs.h b/include/asm-generic/irq_regs.h
new file mode 100644
index 00000000000..5ae1d07d4a1
--- /dev/null
+++ b/include/asm-generic/irq_regs.h
@@ -0,0 +1,37 @@
+/* Fallback per-CPU frame pointer holder
+ *
+ * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _ASM_GENERIC_IRQ_REGS_H
+#define _ASM_GENERIC_IRQ_REGS_H
+
+#include <linux/percpu.h>
+
+/*
+ * Per-cpu current frame pointer - the location of the last exception frame on
+ * the stack
+ */
+DECLARE_PER_CPU(struct pt_regs *, __irq_regs);
+
+static inline struct pt_regs *get_irq_regs(void)
+{
+	return __get_cpu_var(__irq_regs);
+}
+
+static inline struct pt_regs *set_irq_regs(struct pt_regs *new_regs)
+{
+	struct pt_regs *old_regs, **pp_regs = &__get_cpu_var(__irq_regs);
+
+	old_regs = *pp_regs;
+	*pp_regs = new_regs;
+	return old_regs;
+}
+
+#endif /* _ASM_GENERIC_IRQ_REGS_H */
diff --git a/include/asm-i386/apic.h b/include/asm-i386/apic.h
index 3a42b7d6fc9..b9529578fc3 100644
--- a/include/asm-i386/apic.h
+++ b/include/asm-i386/apic.h
@@ -98,7 +98,7 @@ extern void sync_Arb_IDs (void);
 extern void init_bsp_APIC (void);
 extern void setup_local_APIC (void);
 extern void init_apic_mappings (void);
-extern void smp_local_timer_interrupt (struct pt_regs * regs);
+extern void smp_local_timer_interrupt (void);
 extern void setup_boot_APIC_clock (void);
 extern void setup_secondary_APIC_clock (void);
 extern int APIC_init_uniprocessor (void);
@@ -107,7 +107,7 @@ extern void enable_APIC_timer(void);
 
 extern void enable_NMI_through_LVT0 (void * dummy);
 
-void smp_send_timer_broadcast_ipi(struct pt_regs *regs);
+void smp_send_timer_broadcast_ipi(void);
 void switch_APIC_timer_to_ipi(void *cpumask);
 void switch_ipi_to_APIC_timer(void *cpumask);
 #define ARCH_APICTIMER_STOPS_ON_C3	1
diff --git a/include/asm-i386/arch_hooks.h b/include/asm-i386/arch_hooks.h
index 238cf4275b9..a8c1fca9726 100644
--- a/include/asm-i386/arch_hooks.h
+++ b/include/asm-i386/arch_hooks.h
@@ -14,7 +14,7 @@
 extern void init_ISA_irqs(void);
 extern void apic_intr_init(void);
 extern void smp_intr_init(void);
-extern irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+extern irqreturn_t timer_interrupt(int irq, void *dev_id);
 
 /* these are the defined hooks */
 extern void intr_init_hook(void);
diff --git a/include/asm-i386/floppy.h b/include/asm-i386/floppy.h
index 359ead60b71..44ef2f55a8e 100644
--- a/include/asm-i386/floppy.h
+++ b/include/asm-i386/floppy.h
@@ -51,7 +51,7 @@ static char *virtual_dma_addr;
 static int virtual_dma_mode;
 static int doing_pdma;
 
-static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
+static irqreturn_t floppy_hardint(int irq, void *dev_id)
 {
 	register unsigned char st;
 
@@ -63,7 +63,7 @@ static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
 	static int dma_wait=0;
 #endif
 	if (!doing_pdma)
-		return floppy_interrupt(irq, dev_id, regs);
+		return floppy_interrupt(irq, dev_id);
 
 #ifdef TRACE_FLPY_INT
 	if(!calls)
@@ -106,7 +106,7 @@ static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
 		dma_wait=0;
 #endif
 		doing_pdma = 0;
-		floppy_interrupt(irq, dev_id, regs);
+		floppy_interrupt(irq, dev_id);
 		return IRQ_HANDLED;
 	}
 #ifdef TRACE_FLPY_INT
diff --git a/include/asm-i386/hpet.h b/include/asm-i386/hpet.h
index af5d435519d..e47be9a56cc 100644
--- a/include/asm-i386/hpet.h
+++ b/include/asm-i386/hpet.h
@@ -108,7 +108,7 @@ extern int hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned ch
 extern int hpet_set_periodic_freq(unsigned long freq);
 extern int hpet_rtc_dropped_irq(void);
 extern int hpet_rtc_timer_init(void);
-extern irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+extern irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id);
 #endif /* CONFIG_HPET_EMULATE_RTC */
 #endif /* CONFIG_HPET_TIMER */
 #endif /* _I386_HPET_H */
diff --git a/include/asm-i386/hw_irq.h b/include/asm-i386/hw_irq.h
index 88f02a07356..8806c7e002a 100644
--- a/include/asm-i386/hw_irq.h
+++ b/include/asm-i386/hw_irq.h
@@ -41,7 +41,7 @@ fastcall void call_function_interrupt(void);
 fastcall void apic_timer_interrupt(void);
 fastcall void error_interrupt(void);
 fastcall void spurious_interrupt(void);
-fastcall void thermal_interrupt(struct pt_regs *);
+fastcall void thermal_interrupt(void);
 #define platform_legacy_irq(irq)	((irq) < 16)
 #endif
 
diff --git a/include/asm-i386/irq_regs.h b/include/asm-i386/irq_regs.h
new file mode 100644
index 00000000000..3dd9c0b7027
--- /dev/null
+++ b/include/asm-i386/irq_regs.h
@@ -0,0 +1 @@
+#include <asm-generic/irq_regs.h>
diff --git a/include/asm-i386/mach-default/do_timer.h b/include/asm-i386/mach-default/do_timer.h
index 4182c347ef8..7d606e3364a 100644
--- a/include/asm-i386/mach-default/do_timer.h
+++ b/include/asm-i386/mach-default/do_timer.h
@@ -14,11 +14,11 @@
  *	timer interrupt as a means of triggering reschedules etc.
  **/
 
-static inline void do_timer_interrupt_hook(struct pt_regs *regs)
+static inline void do_timer_interrupt_hook(void)
 {
 	do_timer(1);
 #ifndef CONFIG_SMP
-	update_process_times(user_mode_vm(regs));
+	update_process_times(user_mode_vm(get_irq_regs()));
 #endif
 /*
  * In the SMP case we use the local APIC timer interrupt to do the
@@ -26,10 +26,10 @@ static inline void do_timer_interrupt_hook(struct pt_regs *regs)
  * system, in that case we have to call the local interrupt handler.
  */
 #ifndef CONFIG_X86_LOCAL_APIC
-	profile_tick(CPU_PROFILING, regs);
+	profile_tick(CPU_PROFILING);
 #else
 	if (!using_apic_timer)
-		smp_local_timer_interrupt(regs);
+		smp_local_timer_interrupt();
 #endif
 }
 
diff --git a/include/asm-i386/mach-visws/do_timer.h b/include/asm-i386/mach-visws/do_timer.h
index 8db618c5a72..21cd696d4d0 100644
--- a/include/asm-i386/mach-visws/do_timer.h
+++ b/include/asm-i386/mach-visws/do_timer.h
@@ -4,14 +4,14 @@
 #include <asm/i8259.h>
 #include "cobalt.h"
 
-static inline void do_timer_interrupt_hook(struct pt_regs *regs)
+static inline void do_timer_interrupt_hook(void)
 {
 	/* Clear the interrupt */
 	co_cpu_write(CO_CPU_STAT,co_cpu_read(CO_CPU_STAT) & ~CO_STAT_TIMEINTR);
 
 	do_timer(1);
 #ifndef CONFIG_SMP
-	update_process_times(user_mode_vm(regs));
+	update_process_times(user_mode_vm(irq_regs));
 #endif
 /*
  * In the SMP case we use the local APIC timer interrupt to do the
@@ -19,10 +19,10 @@ static inline void do_timer_interrupt_hook(struct pt_regs *regs)
  * system, in that case we have to call the local interrupt handler.
  */
 #ifndef CONFIG_X86_LOCAL_APIC
-	profile_tick(CPU_PROFILING, regs);
+	profile_tick(CPU_PROFILING);
 #else
 	if (!using_apic_timer)
-		smp_local_timer_interrupt(regs);
+		smp_local_timer_interrupt();
 #endif
 }
 
diff --git a/include/asm-i386/mach-voyager/do_timer.h b/include/asm-i386/mach-voyager/do_timer.h
index 099fe9f5c1b..04e69c104a7 100644
--- a/include/asm-i386/mach-voyager/do_timer.h
+++ b/include/asm-i386/mach-voyager/do_timer.h
@@ -1,14 +1,14 @@
 /* defines for inline arch setup functions */
 #include <asm/voyager.h>
 
-static inline void do_timer_interrupt_hook(struct pt_regs *regs)
+static inline void do_timer_interrupt_hook(void)
 {
 	do_timer(1);
 #ifndef CONFIG_SMP
-	update_process_times(user_mode_vm(regs));
+	update_process_times(user_mode_vm(irq_regs));
 #endif
 
-	voyager_timer_interrupt(regs);
+	voyager_timer_interrupt();
 }
 
 static inline int do_timer_overflow(int count)
diff --git a/include/asm-i386/voyager.h b/include/asm-i386/voyager.h
index aaf432dd767..e74c54aa757 100644
--- a/include/asm-i386/voyager.h
+++ b/include/asm-i386/voyager.h
@@ -505,8 +505,8 @@ extern int voyager_memory_detect(int region, __u32 *addr, __u32 *length);
 extern void voyager_smp_intr_init(void);
 extern __u8 voyager_extended_cmos_read(__u16 cmos_address);
 extern void voyager_smp_dump(void);
-extern void voyager_timer_interrupt(struct pt_regs *regs);
-extern void smp_local_timer_interrupt(struct pt_regs * regs);
+extern void voyager_timer_interrupt(void);
+extern void smp_local_timer_interrupt(void);
 extern void voyager_power_off(void);
 extern void smp_voyager_power_off(void *dummy);
 extern void voyager_restart(void);
diff --git a/include/asm-ia64/irq_regs.h b/include/asm-ia64/irq_regs.h
new file mode 100644
index 00000000000..3dd9c0b7027
--- /dev/null
+++ b/include/asm-ia64/irq_regs.h
@@ -0,0 +1 @@
+#include <asm-generic/irq_regs.h>
diff --git a/include/asm-ia64/machvec.h b/include/asm-ia64/machvec.h
index 90cba967df3..7ffbddf5306 100644
--- a/include/asm-ia64/machvec.h
+++ b/include/asm-ia64/machvec.h
@@ -26,7 +26,7 @@ typedef void ia64_mv_setup_t (char **);
 typedef void ia64_mv_cpu_init_t (void);
 typedef void ia64_mv_irq_init_t (void);
 typedef void ia64_mv_send_ipi_t (int, int, int, int);
-typedef void ia64_mv_timer_interrupt_t (int, void *, struct pt_regs *);
+typedef void ia64_mv_timer_interrupt_t (int, void *);
 typedef void ia64_mv_global_tlb_purge_t (struct mm_struct *, unsigned long, unsigned long, unsigned long);
 typedef void ia64_mv_tlb_migrate_finish_t (struct mm_struct *);
 typedef unsigned int ia64_mv_local_vector_to_irq (u8);
@@ -96,7 +96,7 @@ machvec_noop_task (struct task_struct *task)
 }
 
 extern void machvec_setup (char **);
-extern void machvec_timer_interrupt (int, void *, struct pt_regs *);
+extern void machvec_timer_interrupt (int, void *);
 extern void machvec_dma_sync_single (struct device *, dma_addr_t, size_t, int);
 extern void machvec_dma_sync_sg (struct device *, struct scatterlist *, int, int);
 extern void machvec_tlb_migrate_finish (struct mm_struct *);
diff --git a/include/asm-mips/irq_regs.h b/include/asm-mips/irq_regs.h
new file mode 100644
index 00000000000..3dd9c0b7027
--- /dev/null
+++ b/include/asm-mips/irq_regs.h
@@ -0,0 +1 @@
+#include <asm-generic/irq_regs.h>
diff --git a/include/asm-mips/time.h b/include/asm-mips/time.h
index 2d543735668..30f21df3925 100644
--- a/include/asm-mips/time.h
+++ b/include/asm-mips/time.h
@@ -67,7 +67,7 @@ extern unsigned long (*do_gettimeoffset)(void);
 /*
  * high-level timer interrupt routines.
  */
-extern irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+extern irqreturn_t timer_interrupt(int irq, void *dev_id);
 
 /*
  * the corresponding low-level timer interrupt routine.
@@ -77,7 +77,7 @@ extern asmlinkage void ll_timer_interrupt(int irq, struct pt_regs *regs);
 /*
  * profiling and process accouting is done separately in local_timer_interrupt
  */
-extern void local_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+extern void local_timer_interrupt(int irq, void *dev_id);
 extern asmlinkage void ll_local_timer_interrupt(int irq, struct pt_regs *regs);
 
 /*
diff --git a/include/asm-powerpc/irq.h b/include/asm-powerpc/irq.h
index 89ed545b446..f960f5346f4 100644
--- a/include/asm-powerpc/irq.h
+++ b/include/asm-powerpc/irq.h
@@ -825,7 +825,7 @@ extern struct thread_info *softirq_ctx[NR_CPUS];
 
 extern void irq_ctx_init(void);
 extern void call_do_softirq(struct thread_info *tp);
-extern int call_handle_irq(int irq, void *p1, void *p2,
+extern int call_handle_irq(int irq, void *p1,
 			   struct thread_info *tp, void *func);
 #else
 #define irq_ctx_init()
diff --git a/include/asm-powerpc/irq_regs.h b/include/asm-powerpc/irq_regs.h
new file mode 100644
index 00000000000..ba94b51a0a7
--- /dev/null
+++ b/include/asm-powerpc/irq_regs.h
@@ -0,0 +1,2 @@
+#include <asm-generic/irq_regs.h>
+
diff --git a/include/asm-powerpc/smp.h b/include/asm-powerpc/smp.h
index 068f119aa29..20ea7c70bc3 100644
--- a/include/asm-powerpc/smp.h
+++ b/include/asm-powerpc/smp.h
@@ -34,8 +34,7 @@ extern void cpu_die(void);
 #ifdef CONFIG_SMP
 
 extern void smp_send_debugger_break(int cpu);
-struct pt_regs;
-extern void smp_message_recv(int, struct pt_regs *);
+extern void smp_message_recv(int);
 
 #ifdef CONFIG_HOTPLUG_CPU
 extern void fixup_irqs(cpumask_t map);
diff --git a/include/asm-x86_64/apic.h b/include/asm-x86_64/apic.h
index 9e66d32330c..e81d0f289f0 100644
--- a/include/asm-x86_64/apic.h
+++ b/include/asm-x86_64/apic.h
@@ -77,7 +77,7 @@ extern void sync_Arb_IDs (void);
 extern void init_bsp_APIC (void);
 extern void setup_local_APIC (void);
 extern void init_apic_mappings (void);
-extern void smp_local_timer_interrupt (struct pt_regs * regs);
+extern void smp_local_timer_interrupt (void);
 extern void setup_boot_APIC_clock (void);
 extern void setup_secondary_APIC_clock (void);
 extern int APIC_init_uniprocessor (void);
diff --git a/include/asm-x86_64/floppy.h b/include/asm-x86_64/floppy.h
index 32ff5d13271..6ea13c3806f 100644
--- a/include/asm-x86_64/floppy.h
+++ b/include/asm-x86_64/floppy.h
@@ -51,7 +51,7 @@ static char *virtual_dma_addr;
 static int virtual_dma_mode;
 static int doing_pdma;
 
-static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
+static irqreturn_t floppy_hardint(int irq, void *dev_id)
 {
 	register unsigned char st;
 
@@ -63,7 +63,7 @@ static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
 	static int dma_wait=0;
 #endif
 	if (!doing_pdma)
-		return floppy_interrupt(irq, dev_id, regs);
+		return floppy_interrupt(irq, dev_id);
 
 #ifdef TRACE_FLPY_INT
 	if(!calls)
@@ -106,7 +106,7 @@ static irqreturn_t floppy_hardint(int irq, void *dev_id, struct pt_regs * regs)
 		dma_wait=0;
 #endif
 		doing_pdma = 0;
-		floppy_interrupt(irq, dev_id, regs);
+		floppy_interrupt(irq, dev_id);
 		return IRQ_HANDLED;
 	}
 #ifdef TRACE_FLPY_INT
diff --git a/include/asm-x86_64/irq_regs.h b/include/asm-x86_64/irq_regs.h
new file mode 100644
index 00000000000..3dd9c0b7027
--- /dev/null
+++ b/include/asm-x86_64/irq_regs.h
@@ -0,0 +1 @@
+#include <asm-generic/irq_regs.h>
diff --git a/include/asm-x86_64/proto.h b/include/asm-x86_64/proto.h
index c28fc2db217..c181fef786e 100644
--- a/include/asm-x86_64/proto.h
+++ b/include/asm-x86_64/proto.h
@@ -66,7 +66,7 @@ extern void free_bootmem_generic(unsigned long phys, unsigned len);
 extern void load_gs_index(unsigned gs);
 
 extern void stop_timer_interrupt(void);
-extern void main_timer_handler(struct pt_regs *regs);
+extern void main_timer_handler(void);
 
 extern unsigned long end_pfn_map; 
 
@@ -124,7 +124,7 @@ extern int notsc_setup(char *);
 
 extern int gsi_irq_sharing(int gsi);
 
-extern void smp_local_timer_interrupt(struct pt_regs * regs);
+extern void smp_local_timer_interrupt(void);
 
 long do_arch_prctl(struct task_struct *task, int code, unsigned long addr);
 
diff --git a/include/linux/adb.h b/include/linux/adb.h
index b7305b17827..64d8878e144 100644
--- a/include/linux/adb.h
+++ b/include/linux/adb.h
@@ -90,10 +90,10 @@ extern struct blocking_notifier_head adb_client_list;
 int adb_request(struct adb_request *req, void (*done)(struct adb_request *),
 		int flags, int nbytes, ...);
 int adb_register(int default_id,int handler_id,struct adb_ids *ids,
-		 void (*handler)(unsigned char *, int, struct pt_regs *, int));
+		 void (*handler)(unsigned char *, int, int));
 int adb_unregister(int index);
 void adb_poll(void);
-void adb_input(unsigned char *, int, struct pt_regs *, int);
+void adb_input(unsigned char *, int, int);
 int adb_reset_bus(void);
 
 int adb_try_handler_change(int address, int new_id);
diff --git a/include/linux/arcdevice.h b/include/linux/arcdevice.h
index 231ba090ae3..2f85049cfb3 100644
--- a/include/linux/arcdevice.h
+++ b/include/linux/arcdevice.h
@@ -334,7 +334,7 @@ void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc);
 #endif
 
 void arcnet_unregister_proto(struct ArcProto *proto);
-irqreturn_t arcnet_interrupt(int irq, void *dev_id, struct pt_regs *regs);
+irqreturn_t arcnet_interrupt(int irq, void *dev_id);
 struct net_device *alloc_arcdev(char *name);
 
 #endif				/* __KERNEL__ */
diff --git a/include/linux/hiddev.h b/include/linux/hiddev.h
index 945ba1ad14a..acbdae6d7ae 100644
--- a/include/linux/hiddev.h
+++ b/include/linux/hiddev.h
@@ -222,7 +222,7 @@ struct hid_report;
 int hiddev_connect(struct hid_device *);
 void hiddev_disconnect(struct hid_device *);
 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
-		      struct hid_usage *usage, __s32 value, struct pt_regs *regs);
+		      struct hid_usage *usage, __s32 value);
 void hiddev_report_event(struct hid_device *hid, struct hid_report *report);
 int __init hiddev_init(void);
 void hiddev_exit(void);
@@ -230,7 +230,7 @@ void hiddev_exit(void);
 static inline int hiddev_connect(struct hid_device *hid) { return -1; }
 static inline void hiddev_disconnect(struct hid_device *hid) { }
 static inline void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
-		      struct hid_usage *usage, __s32 value, struct pt_regs *regs) { }
+		      struct hid_usage *usage, __s32 value) { }
 static inline void hiddev_report_event(struct hid_device *hid, struct hid_report *report) { }
 static inline int hiddev_init(void) { return 0; }
 static inline void hiddev_exit(void) { }
diff --git a/include/linux/ide.h b/include/linux/ide.h
index 07d8d725541..9c2050293f1 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -1185,7 +1185,7 @@ extern void ide_stall_queue(ide_drive_t *drive, unsigned long timeout);
 
 extern int ide_spin_wait_hwgroup(ide_drive_t *);
 extern void ide_timer_expiry(unsigned long);
-extern irqreturn_t ide_intr(int irq, void *dev_id, struct pt_regs *regs);
+extern irqreturn_t ide_intr(int irq, void *dev_id);
 extern void do_ide_request(request_queue_t *);
 
 void ide_init_disk(struct gendisk *, ide_drive_t *);
diff --git a/include/linux/input.h b/include/linux/input.h
index 5770105471d..c38507ba38b 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -953,7 +953,6 @@ struct input_dev {
 	unsigned int repeat_key;
 	struct timer_list timer;
 
-	struct pt_regs *regs;
 	int state;
 
 	int sync;
@@ -1149,15 +1148,