Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system

Pull "Disintegrate and delete asm/system.h" from David Howells:
 "Here are a bunch of patches to disintegrate asm/system.h into a set of
  separate bits to relieve the problem of circular inclusion
  dependencies.

  I've built all the working defconfigs from all the arches that I can
  and made sure that they don't break.

  The reason for these patches is that I recently encountered a circular
  dependency problem that came about when I produced some patches to
  optimise get_order() by rewriting it to use ilog2().

  This uses bitops - and on the SH arch asm/bitops.h drags in
  asm-generic/get_order.h by a circuituous route involving asm/system.h.

  The main difficulty seems to be asm/system.h.  It holds a number of
  low level bits with no/few dependencies that are commonly used (eg.
  memory barriers) and a number of bits with more dependencies that
  aren't used in many places (eg.  switch_to()).

  These patches break asm/system.h up into the following core pieces:

    (1) asm/barrier.h

        Move memory barriers here.  This already done for MIPS and Alpha.

    (2) asm/switch_to.h

        Move switch_to() and related stuff here.

    (3) asm/exec.h

        Move arch_align_stack() here.  Other process execution related bits
        could perhaps go here from asm/processor.h.

    (4) asm/cmpxchg.h

        Move xchg() and cmpxchg() here as they're full word atomic ops and
        frequently used by atomic_xchg() and atomic_cmpxchg().

    (5) asm/bug.h

        Move die() and related bits.

    (6) asm/auxvec.h

        Move AT_VECTOR_SIZE_ARCH here.

  Other arch headers are created as needed on a per-arch basis."

Fixed up some conflicts from other header file cleanups and moving code
around that has happened in the meantime, so David's testing is somewhat
weakened by that.  We'll find out anything that got broken and fix it..

* tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits)
  Delete all instances of asm/system.h
  Remove all #inclusions of asm/system.h
  Add #includes needed to permit the removal of asm/system.h
  Move all declarations of free_initmem() to linux/mm.h
  Disintegrate asm/system.h for OpenRISC
  Split arch_align_stack() out from asm-generic/system.h
  Split the switch_to() wrapper out of asm-generic/system.h
  Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
  Create asm-generic/barrier.h
  Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h
  Disintegrate asm/system.h for Xtensa
  Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]
  Disintegrate asm/system.h for Tile
  Disintegrate asm/system.h for Sparc
  Disintegrate asm/system.h for SH
  Disintegrate asm/system.h for Score
  Disintegrate asm/system.h for S390
  Disintegrate asm/system.h for PowerPC
  Disintegrate asm/system.h for PA-RISC
  Disintegrate asm/system.h for MN10300
  ...

8 files changed, 114 insertions, 72 deletions

diff --git a/arch/avr32/include/asm/atomic.h b/arch/avr32/include/asm/atomic.h
index e0ac2631c87..61407279208 100644
--- a/arch/avr32/include/asm/atomic.h
+++ b/arch/avr32/include/asm/atomic.h
@@ -15,7 +15,7 @@
 #define __ASM_AVR32_ATOMIC_H
 
 #include <linux/types.h>
-#include <asm/system.h>
+#include <asm/cmpxchg.h>
 
 #define ATOMIC_INIT(i)  { (i) }
 
diff --git a/arch/avr32/include/asm/barrier.h b/arch/avr32/include/asm/barrier.h
new file mode 100644
index 00000000000..808001c9cf8
--- /dev/null
+++ b/arch/avr32/include/asm/barrier.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_AVR32_BARRIER_H
+#define __ASM_AVR32_BARRIER_H
+
+#define mb()                    asm volatile("" : : : "memory")
+#define rmb()                   mb()
+#define wmb()                   asm volatile("sync 0" : : : "memory")
+#define read_barrier_depends()  do { } while(0)
+#define set_mb(var, value)      do { var = value; mb(); } while(0)
+
+#ifdef CONFIG_SMP
+# error "The AVR32 port does not support SMP"
+#else
+# define smp_mb()               barrier()
+# define smp_rmb()              barrier()
+# define smp_wmb()              barrier()
+# define smp_read_barrier_depends() do { } while(0)
+#endif
+
+
+#endif /* __ASM_AVR32_BARRIER_H */
diff --git a/arch/avr32/include/asm/bitops.h b/arch/avr32/include/asm/bitops.h
index b70c19bab63..ebe7ad3f490 100644
--- a/arch/avr32/include/asm/bitops.h
+++ b/arch/avr32/include/asm/bitops.h
@@ -13,7 +13,6 @@
 #endif
 
 #include <asm/byteorder.h>
-#include <asm/system.h>
 
 /*
  * clear_bit() doesn't provide any barrier for the compiler
diff --git a/arch/avr32/include/asm/bug.h b/arch/avr32/include/asm/bug.h
index 2aa373cc61b..85a92d099ad 100644
--- a/arch/avr32/include/asm/bug.h
+++ b/arch/avr32/include/asm/bug.h
@@ -70,4 +70,9 @@
 
 #include <asm-generic/bug.h>
 
+struct pt_regs;
+void die(const char *str, struct pt_regs *regs, long err);
+void _exception(long signr, struct pt_regs *regs, int code,
+                unsigned long addr);
+
 #endif /* __ASM_AVR32_BUG_H */
diff --git a/arch/avr32/include/asm/system.h b/arch/avr32/include/asm/cmpxchg.h
index 62d9ded0163..962a6aeab78 100644
--- a/arch/avr32/include/asm/system.h
+++ b/arch/avr32/include/asm/cmpxchg.h
@@ -1,76 +1,22 @@
 /*
+ * Atomic operations that C can't guarantee us.  Useful for
+ * resource counting etc.
+ *
+ * But use these as seldom as possible since they are slower than
+ * regular operations.
+ *
  * Copyright (C) 2004-2006 Atmel Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
-#ifndef __ASM_AVR32_SYSTEM_H
-#define __ASM_AVR32_SYSTEM_H
-
-#include <linux/compiler.h>
-#include <linux/linkage.h>
-#include <linux/types.h>
-
-#include <asm/ptrace.h>
-#include <asm/sysreg.h>
+#ifndef __ASM_AVR32_CMPXCHG_H
+#define __ASM_AVR32_CMPXCHG_H
 
 #define xchg(ptr,x) \
         ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
 
-#define nop() asm volatile("nop")
-
-#define mb()                    asm volatile("" : : : "memory")
-#define rmb()                   mb()
-#define wmb()                   asm volatile("sync 0" : : : "memory")
-#define read_barrier_depends()  do { } while(0)
-#define set_mb(var, value)      do { var = value; mb(); } while(0)
-
-/*
- * Help PathFinder and other Nexus-compliant debuggers keep track of
- * the current PID by emitting an Ownership Trace Message each time we
- * switch task.
- */
-#ifdef CONFIG_OWNERSHIP_TRACE
-#include <asm/ocd.h>
-#define finish_arch_switch(prev)                        \
-        do {                                            \
-                ocd_write(PID, prev->pid);              \
-                ocd_write(PID, current->pid);           \
-        } while(0)
-#endif
-
-/*
- * switch_to(prev, next, last) should switch from task `prev' to task
- * `next'. `prev' will never be the same as `next'.
- *
- * We just delegate everything to the __switch_to assembly function,
- * which is implemented in arch/avr32/kernel/switch_to.S
- *
- * mb() tells GCC not to cache `current' across this call.
- */
-struct cpu_context;
-struct task_struct;
-extern struct task_struct *__switch_to(struct task_struct *,
-                                       struct cpu_context *,
-                                       struct cpu_context *);
-#define switch_to(prev, next, last)                                     \
-        do {                                                            \
-                last = __switch_to(prev, &prev->thread.cpu_context + 1, \
-                                   &next->thread.cpu_context);          \
-        } while (0)
-
-#ifdef CONFIG_SMP
-# error "The AVR32 port does not support SMP"
-#else
-# define smp_mb()               barrier()
-# define smp_rmb()              barrier()
-# define smp_wmb()              barrier()
-# define smp_read_barrier_depends() do { } while(0)
-#endif
-
-#include <linux/irqflags.h>
-
 extern void __xchg_called_with_bad_pointer(void);
 
 static inline unsigned long xchg_u32(u32 val, volatile u32 *m)
@@ -168,11 +114,4 @@ static inline unsigned long __cmpxchg_local(volatile void *ptr,
 
 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 
-struct pt_regs;
-void die(const char *str, struct pt_regs *regs, long err);
-void _exception(long signr, struct pt_regs *regs, int code,
-                unsigned long addr);
-
-#define arch_align_stack(x)     (x)
-
-#endif /* __ASM_AVR32_SYSTEM_H */
+#endif /* __ASM_AVR32_CMPXCHG_H */
diff --git a/arch/avr32/include/asm/exec.h b/arch/avr32/include/asm/exec.h
new file mode 100644
index 00000000000..f467be8bf82
--- /dev/null
+++ b/arch/avr32/include/asm/exec.h
@@ -0,0 +1,13 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_AVR32_EXEC_H
+#define __ASM_AVR32_EXEC_H
+
+#define arch_align_stack(x)     (x)
+
+#endif /* __ASM_AVR32_EXEC_H */
diff --git a/arch/avr32/include/asm/special_insns.h b/arch/avr32/include/asm/special_insns.h
new file mode 100644
index 00000000000..f922218dfaa
--- /dev/null
+++ b/arch/avr32/include/asm/special_insns.h
@@ -0,0 +1,13 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_AVR32_SPECIAL_INSNS_H
+#define __ASM_AVR32_SPECIAL_INSNS_H
+
+#define nop() asm volatile("nop")
+
+#endif /* __ASM_AVR32_SPECIAL_INSNS_H */
diff --git a/arch/avr32/include/asm/switch_to.h b/arch/avr32/include/asm/switch_to.h
new file mode 100644
index 00000000000..9a8e9d5208d
--- /dev/null
+++ b/arch/avr32/include/asm/switch_to.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_AVR32_SWITCH_TO_H
+#define __ASM_AVR32_SWITCH_TO_H
+
+/*
+ * Help PathFinder and other Nexus-compliant debuggers keep track of
+ * the current PID by emitting an Ownership Trace Message each time we
+ * switch task.
+ */
+#ifdef CONFIG_OWNERSHIP_TRACE
+#include <asm/ocd.h>
+#define finish_arch_switch(prev)                        \
+        do {                                            \
+                ocd_write(PID, prev->pid);              \
+                ocd_write(PID, current->pid);           \
+        } while(0)
+#endif
+
+/*
+ * switch_to(prev, next, last) should switch from task `prev' to task
+ * `next'. `prev' will never be the same as `next'.
+ *
+ * We just delegate everything to the __switch_to assembly function,
+ * which is implemented in arch/avr32/kernel/switch_to.S
+ *
+ * mb() tells GCC not to cache `current' across this call.
+ */
+struct cpu_context;
+struct task_struct;
+extern struct task_struct *__switch_to(struct task_struct *,
+                                       struct cpu_context *,
+                                       struct cpu_context *);
+#define switch_to(prev, next, last)                                     \
+        do {                                                            \
+                last = __switch_to(prev, &prev->thread.cpu_context + 1, \
+                                   &next->thread.cpu_context);          \
+        } while (0)
+
+
+#endif /* __ASM_AVR32_SWITCH_TO_H */