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
  ...

6 files changed, 140 insertions, 98 deletions

diff --git a/arch/frv/include/asm/atomic.h b/arch/frv/include/asm/atomic.h
index 0d8a7d6..b86329d 100644
--- a/arch/frv/include/asm/atomic.h
+++ b/arch/frv/include/asm/atomic.h
@@ -16,7 +16,7 @@
 
 #include <linux/types.h>
 #include <asm/spr-regs.h>
-#include <asm/system.h>
+#include <asm/cmpxchg.h>
 
 #ifdef CONFIG_SMP
 #error not SMP safe
@@ -181,61 +181,6 @@ static inline void atomic64_dec(atomic64_t *v)
 #define atomic64_dec_and_test(v)	(atomic64_dec_return((v)) == 0)
 #define atomic64_inc_and_test(v)	(atomic64_inc_return((v)) == 0)
 
-/*****************************************************************************/
-/*
- * exchange value with memory
- */
-extern uint64_t __xchg_64(uint64_t i, volatile void *v);
-
-#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
-
-#define xchg(ptr, x)								\
-({										\
-	__typeof__(ptr) __xg_ptr = (ptr);					\
-	__typeof__(*(ptr)) __xg_orig;						\
-										\
-	switch (sizeof(__xg_orig)) {						\
-	case 4:									\
-		asm volatile(							\
-			"swap%I0 %M0,%1"					\
-			: "+m"(*__xg_ptr), "=r"(__xg_orig)			\
-			: "1"(x)						\
-			: "memory"						\
-			);							\
-		break;								\
-										\
-	default:								\
-		__xg_orig = (__typeof__(__xg_orig))0;				\
-		asm volatile("break");						\
-		break;								\
-	}									\
-										\
-	__xg_orig;								\
-})
-
-#else
-
-extern uint32_t __xchg_32(uint32_t i, volatile void *v);
-
-#define xchg(ptr, x)										\
-({												\
-	__typeof__(ptr) __xg_ptr = (ptr);							\
-	__typeof__(*(ptr)) __xg_orig;								\
-												\
-	switch (sizeof(__xg_orig)) {								\
-	case 4: __xg_orig = (__typeof__(*(ptr))) __xchg_32((uint32_t) x, __xg_ptr);	break;	\
-	default:										\
-		__xg_orig = (__typeof__(__xg_orig))0;									\
-		asm volatile("break");								\
-		break;										\
-	}											\
-	__xg_orig;										\
-})
-
-#endif
-
-#define tas(ptr) (xchg((ptr), 1))
-
 #define atomic_cmpxchg(v, old, new)	(cmpxchg(&(v)->counter, old, new))
 #define atomic_xchg(v, new)		(xchg(&(v)->counter, new))
 #define atomic64_cmpxchg(v, old, new)	(__cmpxchg_64(old, new, &(v)->counter))
diff --git a/arch/frv/include/asm/barrier.h b/arch/frv/include/asm/barrier.h
new file mode 100644
index 0000000..06776ad
--- /dev/null
+++ b/arch/frv/include/asm/barrier.h
@@ -0,0 +1,29 @@
+/* FR-V CPU memory barrier definitions
+ *
+ * Copyright (C) 2003 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_BARRIER_H
+#define _ASM_BARRIER_H
+
+#define nop()			asm volatile ("nop"::)
+
+#define mb()			asm volatile ("membar" : : :"memory")
+#define rmb()			asm volatile ("membar" : : :"memory")
+#define wmb()			asm volatile ("membar" : : :"memory")
+#define read_barrier_depends()	do { } while (0)
+
+#define smp_mb()			barrier()
+#define smp_rmb()			barrier()
+#define smp_wmb()			barrier()
+#define smp_read_barrier_depends()	do {} while(0)
+#define set_mb(var, value) \
+	do { var = (value); barrier(); } while (0)
+
+#endif /* _ASM_BARRIER_H */
diff --git a/arch/frv/include/asm/bug.h b/arch/frv/include/asm/bug.h
index 2e05450..dd01bcf 100644
--- a/arch/frv/include/asm/bug.h
+++ b/arch/frv/include/asm/bug.h
@@ -51,4 +51,6 @@ do {						\
 
 #include <asm-generic/bug.h>
 
+extern void die_if_kernel(const char *, ...) __attribute__((format(printf, 1, 2)));
+
 #endif
diff --git a/arch/frv/include/asm/system.h b/arch/frv/include/asm/cmpxchg.h
index 6c10fd2..5b04dd0 100644
--- a/arch/frv/include/asm/system.h
+++ b/arch/frv/include/asm/cmpxchg.h
@@ -1,6 +1,9 @@
-/* system.h: FR-V CPU control definitions
+/* xchg and cmpxchg operation emulation for FR-V
  *
- * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
+ * For an explanation of how atomic ops work in this arch, see:
+ *   Documentation/frv/atomic-ops.txt
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
  * Written by David Howells (dhowells@redhat.com)
  *
  * This program is free software; you can redistribute it and/or
@@ -8,54 +11,65 @@
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */
-
-#ifndef _ASM_SYSTEM_H
-#define _ASM_SYSTEM_H
+#ifndef _ASM_CMPXCHG_H
+#define _ASM_CMPXCHG_H
 
 #include <linux/types.h>
-#include <linux/linkage.h>
-#include <linux/kernel.h>
-
-struct thread_struct;
 
+/*****************************************************************************/
 /*
- * switch_to(prev, next) should switch from task `prev' to `next'
- * `prev' will never be the same as `next'.
- * The `mb' is to tell GCC not to cache `current' across this call.
+ * exchange value with memory
  */
-extern asmlinkage
-struct task_struct *__switch_to(struct thread_struct *prev_thread,
-				struct thread_struct *next_thread,
-				struct task_struct *prev);
-
-#define switch_to(prev, next, last)					\
-do {									\
-	(prev)->thread.sched_lr =					\
-		(unsigned long) __builtin_return_address(0);		\
-	(last) = __switch_to(&(prev)->thread, &(next)->thread, (prev));	\
-	mb();								\
-} while(0)
+extern uint64_t __xchg_64(uint64_t i, volatile void *v);
 
-/*
- * Force strict CPU ordering.
- */
-#define nop()			asm volatile ("nop"::)
-#define mb()			asm volatile ("membar" : : :"memory")
-#define rmb()			asm volatile ("membar" : : :"memory")
-#define wmb()			asm volatile ("membar" : : :"memory")
-#define read_barrier_depends()	do { } while (0)
+#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS
+
+#define xchg(ptr, x)								\
+({										\
+	__typeof__(ptr) __xg_ptr = (ptr);					\
+	__typeof__(*(ptr)) __xg_orig;						\
+										\
+	switch (sizeof(__xg_orig)) {						\
+	case 4:									\
+		asm volatile(							\
+			"swap%I0 %M0,%1"					\
+			: "+m"(*__xg_ptr), "=r"(__xg_orig)			\
+			: "1"(x)						\
+			: "memory"						\
+			);							\
+		break;								\
+										\
+	default:								\
+		__xg_orig = (__typeof__(__xg_orig))0;				\
+		asm volatile("break");						\
+		break;								\
+	}									\
+										\
+	__xg_orig;								\
+})
 
-#define smp_mb()			barrier()
-#define smp_rmb()			barrier()
-#define smp_wmb()			barrier()
-#define smp_read_barrier_depends()	do {} while(0)
-#define set_mb(var, value) \
-	do { var = (value); barrier(); } while (0)
+#else
 
-extern void die_if_kernel(const char *, ...) __attribute__((format(printf, 1, 2)));
-extern void free_initmem(void);
+extern uint32_t __xchg_32(uint32_t i, volatile void *v);
+
+#define xchg(ptr, x)										\
+({												\
+	__typeof__(ptr) __xg_ptr = (ptr);							\
+	__typeof__(*(ptr)) __xg_orig;								\
+												\
+	switch (sizeof(__xg_orig)) {								\
+	case 4: __xg_orig = (__typeof__(*(ptr))) __xchg_32((uint32_t) x, __xg_ptr);	break;	\
+	default:										\
+		__xg_orig = (__typeof__(__xg_orig))0;									\
+		asm volatile("break");								\
+		break;										\
+	}											\
+	__xg_orig;										\
+})
+
+#endif
 
-#define arch_align_stack(x) (x)
+#define tas(ptr) (xchg((ptr), 1))
 
 /*****************************************************************************/
 /*
@@ -155,4 +169,4 @@ static inline unsigned long __cmpxchg_local(volatile void *ptr,
 			(unsigned long)(n), sizeof(*(ptr))))
 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 
-#endif /* _ASM_SYSTEM_H */
+#endif /* _ASM_CMPXCHG_H */
diff --git a/arch/frv/include/asm/exec.h b/arch/frv/include/asm/exec.h
new file mode 100644
index 0000000..65c9130
--- /dev/null
+++ b/arch/frv/include/asm/exec.h
@@ -0,0 +1,17 @@
+/* FR-V CPU executable handling
+ *
+ * Copyright (C) 2003 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_EXEC_H
+#define _ASM_EXEC_H
+
+#define arch_align_stack(x) (x)
+
+#endif /* _ASM_EXEC_H */
diff --git a/arch/frv/include/asm/switch_to.h b/arch/frv/include/asm/switch_to.h
new file mode 100644
index 0000000..2cf0f6a
--- /dev/null
+++ b/arch/frv/include/asm/switch_to.h
@@ -0,0 +1,35 @@
+/* FR-V CPU basic task switching
+ *
+ * Copyright (C) 2003 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_SWITCH_TO_H
+#define _ASM_SWITCH_TO_H
+
+#include <linux/thread_info.h>
+
+/*
+ * switch_to(prev, next) should switch from task `prev' to `next'
+ * `prev' will never be the same as `next'.
+ * The `mb' is to tell GCC not to cache `current' across this call.
+ */
+extern asmlinkage
+struct task_struct *__switch_to(struct thread_struct *prev_thread,
+				struct thread_struct *next_thread,
+				struct task_struct *prev);
+
+#define switch_to(prev, next, last)					\
+do {									\
+	(prev)->thread.sched_lr =					\
+		(unsigned long) __builtin_return_address(0);		\
+	(last) = __switch_to(&(prev)->thread, &(next)->thread, (prev));	\
+	mb();								\
+} while(0)
+
+#endif /* _ASM_SWITCH_TO_H */