• Peter Zijlstra's avatar
    locking/atomic, arch/arm64: Implement... · e490f9b1
    Peter Zijlstra authored
    locking/atomic, arch/arm64: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
    
    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).
    
    [wildea01: compile fixes for ll/sc]
    Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Catalin Marinas <catalin.marinas@arm.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
    Cc: Mark Rutland <mark.rutland@arm.com>
    Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Steve Capper <steve.capper@arm.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Will Deacon <will.deacon@arm.com>
    Cc: linux-arch@vger.kernel.org
    Cc: linux-arm-kernel@lists.infradead.org
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
    e490f9b1
atomic.h 8.39 KB