• Peter Zijlstra's avatar
    locking/atomic, arch/powerpc: Implement... · a28cc7bb
    Peter Zijlstra authored
    locking/atomic, arch/powerpc: Implement atomic{,64}_fetch_{add,sub,and,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).
    Tested-by: default avatarBoqun Feng <boqun.feng@gmail.com>
    Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Michael Ellerman <mpe@ellerman.id.au>
    Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
    Cc: Paul Mackerras <paulus@samba.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: linux-arch@vger.kernel.org
    Cc: linux-kernel@vger.kernel.org
    Cc: linuxppc-dev@lists.ozlabs.org
    Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
    a28cc7bb
atomic.h 13.5 KB