• Kees Cook's avatar
    locking/refcount: Create unchecked atomic_t implementation · fd25d19f
    Kees Cook authored
    Many subsystems will not use refcount_t unless there is a way to build the
    kernel so that there is no regression in speed compared to atomic_t. This
    adds CONFIG_REFCOUNT_FULL to enable the full refcount_t implementation
    which has the validation but is slightly slower. When not enabled,
    refcount_t uses the basic unchecked atomic_t routines, which results in
    no code changes compared to just using atomic_t directly.
    Signed-off-by: default avatarKees Cook <keescook@chromium.org>
    Acked-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    Cc: Alexey Dobriyan <adobriyan@gmail.com>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Arnd Bergmann <arnd@arndb.de>
    Cc: Christoph Hellwig <hch@infradead.org>
    Cc: David S. Miller <davem@davemloft.net>
    Cc: David Windsor <dwindsor@gmail.com>
    Cc: Davidlohr Bueso <dave@stgolabs.net>
    Cc: Elena Reshetova <elena.reshetova@intel.com>
    Cc: Eric Biggers <ebiggers3@gmail.com>
    Cc: Eric W. Biederman <ebiederm@xmission.com>
    Cc: Hans Liljestrand <ishkamiel@gmail.com>
    Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
    Cc: Jann Horn <jannh@google.com>
    Cc: Josh Poimboeuf <jpoimboe@redhat.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Manfred Spraul <manfred@colorfullife.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Rik van Riel <riel@redhat.com>
    Cc: Serge E. Hallyn <serge@hallyn.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: arozansk@redhat.com
    Cc: axboe@kernel.dk
    Cc: linux-arch <linux-arch@vger.kernel.org>
    Link: http://lkml.kernel.org/r/20170621200026.GA115679@beastSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
    fd25d19f
refcount.c 10.2 KB