kernel/arch/arm/include/asm/atomic.h, branch linux-4.15.y

locking/atomic: Remove linux/atomic.h:atomic_fetch_or()

2016-06-16T08:48:32Z

Since all architectures have this implemented now natively, remove this dead code. Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

locking/atomic, arch/arm: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()

2016-06-16T08:48:20Z

Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) Acked-by: Will Deacon Cc: Andrew Morton Cc: Davidlohr Bueso Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Russell King Cc: Thomas Gleixner Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

ARM, locking/atomics: Implement _relaxed variants of atomic[64]_{inc,dec}

2015-10-20T08:17:23Z

Now that the core code supports acquire/release/relaxed versions of the atomic_inc family, implement only the _relaxed flavours in the ARM backend so that we get all of the others for free. Signed-off-by: Will Deacon Signed-off-by: Peter Zijlstra (Intel) Acked-by: Davidlohr Bueso Cc: Andrew Morton Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1444227038-12533-1-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar

atomic, arch: Audit atomic_{read,set}()

2015-09-23T07:54:28Z

This patch makes sure that atomic_{read,set}() are at least {READ,WRITE}_ONCE(). We already had the 'requirement' that atomic_read() should use ACCESS_ONCE(), and most archs had this, but a few were lacking. All are now converted to use READ_ONCE(). And, by a symmetry and general paranoia argument, upgrade atomic_set() to use WRITE_ONCE(). Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Dmitry Vyukov Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: james.hogan@imgtec.com Cc: linux-kernel@vger.kernel.org Cc: oleg@redhat.com Cc: will.deacon@arm.com Signed-off-by: Ingo Molnar

locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations

2015-08-12T09:59:10Z

By defining our SMP atomics in terms of relaxed operations, we gain a small reduction in code size and have acquire/release/fence variants generated automatically by the core code. Signed-off-by: Will Deacon Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Waiman.Long@hp.com Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1438880084-18856-9-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar

atomic: Provide atomic_{or,xor,and}

2015-07-27T12:06:24Z

Implement atomic logic ops -- atomic_{or,xor,and}. These will replace the atomic_{set,clear}_mask functions that are available on some archs. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner

arm: Provide atomic_{or,xor,and}

2015-07-27T12:06:21Z

locking,arch: Use ACCESS_ONCE() instead of cast to volatile in atomic_read()

2014-10-03T04:06:23Z

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 Acked-by: Jesper Nilsson Acked-by: Hans-Christian Egtvedt Acked-by: Max Filippov Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds 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

locking,arch,arm: Fold atomic_ops

2014-08-14T10:48:04Z

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 Acked-by: Will Deacon Cc: Chen Gang Cc: Linus Torvalds Cc: Nicolas Pitre Cc: Paul E. McKenney Cc: Russell King Cc: Albin Tonnerre Cc: Victor Kamensky Cc: Catalin Marinas Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20140508135851.939725247@infradead.org Signed-off-by: Ingo Molnar

arch,arm: Convert smp_mb__*()

2014-04-18T09:40:32Z

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 Acked-by: Paul E. McKenney Link: http://lkml.kernel.org/n/tip-yijo7sglsl7uusbp13upcuvo@git.kernel.org Cc: Albin Tonnerre Cc: Catalin Marinas Cc: Chen Gang Cc: Linus Torvalds Cc: Nicolas Pitre Cc: Russell King Cc: Victor Kamensky Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar