linux-toradex.git/arch/arm/include/asm/atomic.h, branch v4.2.5 Linux kernel for Apalis and Colibri modules locking,arch: Use ACCESS_ONCE() instead of cast to volatile in atomic_read() 2014-10-03T04:06:23+00:00 Pranith Kumar bobby.prani@gmail.com 2014-09-23T14:29:50+00:00 2291059c852706c6f5ffb400366042b7625066cd Use the much more reader friendly ACCESS_ONCE() instead of the cast to volatile. This is purely a stylistic change. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/1411482607-20948-1-git-send-email-bobby.prani@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> 
Use the much more reader friendly ACCESS_ONCE() instead of the cast to volatile.
This is purely a stylistic change.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/1411482607-20948-1-git-send-email-bobby.prani@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
locking,arch,arm: Fold atomic_ops 2014-08-14T10:48:04+00:00 Peter Zijlstra peterz@infradead.org 2014-03-23T15:38:18+00:00 aee9a55452f0371258e18b41649ce650ff344090 Many of the atomic op implementations are the same except for one instruction; fold the lot into a few CPP macros and reduce LoC. This also prepares for easy addition of new ops. Requires the asm_op because of eor. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Chen Gang <gang.chen@asianux.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nicolas Pitre <nico@linaro.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Albin Tonnerre <albin.tonnerre@arm.com> Cc: Victor Kamensky <victor.kamensky@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20140508135851.939725247@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org> 
Many of the atomic op implementations are the same except for one
instruction; fold the lot into a few CPP macros and reduce LoC.

This also prepares for easy addition of new ops.

Requires the asm_op because of eor.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Chen Gang <gang.chen@asianux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Albin Tonnerre <albin.tonnerre@arm.com>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20140508135851.939725247@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch,arm: Convert smp_mb__*() 2014-04-18T09:40:32+00:00 Peter Zijlstra peterz@infradead.org 2014-03-12T16:11:00+00:00 030d0178bdbd237c1f0577f03bbc1d7140a75044 ARM uses ll/sc primitives that do not imply barriers for all regular atomic ops, therefore smp_mb__{before,after} need be a full barrier. Since ARM doesn't use asm-generic/barrier.h include the required definitions in its asm/barrier.h Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-yijo7sglsl7uusbp13upcuvo@git.kernel.org Cc: Albin Tonnerre <albin.tonnerre@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Gang <gang.chen@asianux.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nicolas Pitre <nico@linaro.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Victor Kamensky <victor.kamensky@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> 
ARM uses ll/sc primitives that do not imply barriers for all regular
atomic ops, therefore smp_mb__{before,after} need be a full barrier.

Since ARM doesn't use asm-generic/barrier.h include the required
definitions in its asm/barrier.h

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-yijo7sglsl7uusbp13upcuvo@git.kernel.org
Cc: Albin Tonnerre <albin.tonnerre@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Gang <gang.chen@asianux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
ARM: 7983/1: atomics: implement a better __atomic_add_unless for v6+ 2014-02-25T11:35:08+00:00 Will Deacon will.deacon@arm.com 2014-02-21T16:01:48+00:00 db38ee874c48713d0723221d08332242e0088970 Looking at perf profiles of multi-threaded hackbench runs, a significant performance hit appears to manifest from the cmpxchg loop used to implement the 32-bit atomic_add_unless function. This can be mitigated by writing a direct implementation of __atomic_add_unless which doesn't require iteration outside of the atomic operation. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Looking at perf profiles of multi-threaded hackbench runs, a significant
performance hit appears to manifest from the cmpxchg loop used to
implement the 32-bit atomic_add_unless function. This can be mitigated
by writing a direct implementation of __atomic_add_unless which doesn't
require iteration outside of the atomic operation.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 7984/1: prefetch: add prefetchw invocations for barriered atomics 2014-02-25T11:30:20+00:00 Will Deacon will.deacon@arm.com 2014-02-21T16:01:48+00:00 c32ffce0f66e5d1d4856254516e24f5ef275cd00 After a bunch of benchmarking on the interaction between dmb and pldw, it turns out that issuing the pldw *after* the dmb instruction can give modest performance gains (~3% atomic_add_return improvement on a dual A15). This patch adds prefetchw invocations to our barriered atomic operations including cmpxchg, test_and_xxx and futexes. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
After a bunch of benchmarking on the interaction between dmb and pldw,
it turns out that issuing the pldw *after* the dmb instruction can
give modest performance gains (~3% atomic_add_return improvement on a
dual A15).

This patch adds prefetchw invocations to our barriered atomic operations
including cmpxchg, test_and_xxx and futexes.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Merge branch 'devel-stable' into for-next 2013-11-12T10:58:59+00:00 Russell King rmk+kernel@arm.linux.org.uk 2013-11-12T10:58:59+00:00 df762eccbadf87850fbee444d729e0f1b1e946f1 Conflicts: arch/arm/include/asm/atomic.h arch/arm/include/asm/hardirq.h arch/arm/kernel/smp.c 
Conflicts:
	arch/arm/include/asm/atomic.h
	arch/arm/include/asm/hardirq.h
	arch/arm/kernel/smp.c
ARM: 7868/1: arm/arm64: remove atomic_clear_mask() in "include/asm/atomic.h" 2013-11-09T00:00:13+00:00 Chen Gang gang.chen@asianux.com 2013-10-26T14:07:41+00:00 aed3a4ed7222ae37860ae33cbad3ea7a6b2eaf8e In current kernel wide source code, except other architectures, only s390 scsi drivers use atomic_clear_mask(), and arm/arm64 need not support s390 drivers. So remove atomic_clear_mask() from "arm[64]/include/asm/atomic.h". Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
In current kernel wide source code, except other architectures, only
s390 scsi drivers use atomic_clear_mask(), and arm/arm64 need not
support s390 drivers.

So remove atomic_clear_mask() from "arm[64]/include/asm/atomic.h".

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 7867/1: include: asm: use 'int' instead of 'unsigned long' for 'oldval' in atomic_cmpxchg(). 2013-11-09T00:00:12+00:00 Chen Gang gang.chen@asianux.com 2013-10-26T14:07:25+00:00 4dcc1cf7316a26e112f5c9fcca531ff98ef44700 For atomic_cmpxchg(), the type of 'oldval' need be 'int' to match the type of "*ptr" (used by 'ldrex' instruction) and 'old' (used by 'teq' instruction). Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
For atomic_cmpxchg(), the type of 'oldval' need be 'int' to match the
type of "*ptr" (used by 'ldrex' instruction) and 'old' (used by 'teq'
instruction).

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM: 7866/1: include: asm: use 'long long' instead of 'u64' within atomic.h 2013-11-09T00:00:10+00:00 Chen Gang gang.chen@asianux.com 2013-10-26T14:07:04+00:00 237f12337cfa2175474e4dd015bc07a25eb9080d atomic* value is signed value, and atomic* functions need also process signed value (parameter value, and return value), so 32-bit arm need use 'long long' instead of 'u64'. After replacement, it will also fix a bug for atomic64_add_negative(): "u64 is never less than 0". The modifications are: in vim, use "1,% s/\<u64\>/long long/g" command. remove '__aligned(8)' which is useless for 64-bit. be sure of 80 column limitation after replacement. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
atomic* value is signed value, and atomic* functions need also process
signed value (parameter value, and return value), so 32-bit arm need
use 'long long' instead of 'u64'.

After replacement, it will also fix a bug for atomic64_add_negative():
"u64 is never less than 0".

The modifications are:

  in vim, use "1,% s/\<u64\>/long long/g" command.
  remove '__aligned(8)' which is useless for 64-bit.
  be sure of 80 column limitation after replacement.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Merge branch 'baserock/bjdooks/312-rc4/be/core-v3' of git://git.baserock.org/delta/linux into devel-stable 2013-10-30T22:20:26+00:00 Russell King rmk+kernel@arm.linux.org.uk 2013-10-28T00:43:41+00:00 2098990e7c558c175b96213d41058983e00a7919 Conflicts: arch/arm/kernel/head.S This series has been well tested and it would be great to get this merged now. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> 
Conflicts:
	arch/arm/kernel/head.S

This series has been well tested and it would be great to get this
merged now.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>