Add a local processor version of cmpxchg for ppc.

Implements __cmpxchg_u32_local and uses it for 32 bits cmpxchg_local.
It uses the non NMI safe cmpxchg_local_generic for 1, 2 and 8 bytes
cmpxchg_local.

Signed-off-by: Gunnar Larisch <gl@denx.de>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 4f9a58d75bfe82ab2b8ba5b8506dfb190a267834 ("increase
AT_VECTOR_SIZE to terminate saved_auxv properly") changes the size of
AT_VECTOR_SIZE from hard coded '44' to a calculation based on the value
of AT_VECTOR_SIZE_ARCH and AT_VECTOR_SIZE_BASE.

The change works for arch/powerpc, but it breaks arch/ppc because the
needed AT_VECTOR_SIZE_ARCH is not present in include/asm-ppc/system.h
and a default value of 0 is used instead.  This results in
AT_VECTOR_SIZE being too small and it causes a kernel crash on loading
init.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The recent signal rework broke ARCH=ppc builds with the following
error:

CC      arch/powerpc/kernel/signal.o
arch/powerpc/kernel/signal.c: In function ‘do_signal’:
arch/powerpc/kernel/signal.c:142: error: implicit declaration of
function ‘set_dabr’
make[1]: *** [arch/powerpc/kernel/signal.o] Error 1

This fixes it by including a function prototype in asm-ppc/system.h.

Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

Since Ingo's recent scheduler rewrite which was merged as commit
0437e109e1841607f2988891eaa36c531c6aa6ac sched_cacheflush is unused.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tas() has no users, so get rid of it.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: <linux-arch@vger.kernel.org>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

atomic_add_unless as inline. Remove system.h atomic.h circular dependency.
I agree (with Andi Kleen) this typeof is not needed and more error
prone. All the original atomic.h code that uses cmpxchg (which includes
the atomic_add_unless) uses defines instead of inline functions,
probably to circumvent a circular dependency between system.h and
atomic.h on powerpc (which my patch addresses). Therefore, it makes
sense to use inline functions that will provide type checking.

atomic_add_unless as inline. Remove system.h atomic.h circular dependency.
Digging into the FRV architecture shows me that it is also affected by
such a circular dependency. Here is the diff applying this against the
rest of my atomic.h patches.

It applies over the atomic.h standardization patches.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

set_wmb should not be used in the kernel because it just confuses the
code more and has no benefit.  Since it is not currently used in the
kernel this patch removes it so that new code does not include it.

All archs define set_wmb(var, value) to do { var = value; wmb(); }
while(0) except ia64 and sparc which use a mb() instead.  But this is
still moot since it is not used anyway.

Hasn't been tested on any archs but x86 and x86_64 (and only compiled
tested)

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Fix up delete/modify conflict of arch/ppc/kernel/process.c by hand (it's
gone, gone, gone).

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Add per-arch sched_cacheflush() which is a write-back cacheflush used by
the migration-cost calibration code at bootup time.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Commit 5388fb1025443ec223ba556b10efc4c5f83f8682 made signal_32.c
use discard_lazy_cpu_state, which broke ARCH=ppc because that
uses the common signal_32.c but has its own process.c.  Make ARCH=ppc
use the common process.c to fix this and to reduce the amount
of duplicated code.

Signed-off-by: Paul Mackerras <paulus@samba.org>