Hi Andrew,

After merging the akpm tree, today's linux-next build (powerpc
ppc64_defconfig) failed like this:

fs/aio.c: In function 'put_ioctx':
fs/aio.c:386:6: error: void value not ignored as it ought to be
  if (percpu_ref_put(&ctx->users))
      ^
fs/aio.c: In function 'ioctx_alloc':
fs/aio.c:427:2: error: too few arguments to function 'percpu_ref_init'
  percpu_ref_init(&ctx->users);
  ^
In file included from fs/aio.c:40:0:
include/linux/percpu-refcount.h:69:5: note: declared here
 int percpu_ref_init(struct percpu_ref *, percpu_ref_release *);
     ^
fs/aio.c: In function 'kill_ioctx':
fs/aio.c:510:6: error: void value not ignored as it ought to be
  if (percpu_ref_kill(&ctx->users)) {
      ^
fs/aio.c: In function 'exit_aio':
fs/aio.c:577:8: error: void value not ignored as it ought to be
    if (percpu_ref_kill(&ctx[i]->users)) {
        ^
fs/aio.c: In function 'aio_read_events':
fs/aio.c:978:2: error: implicit declaration of function 'percpu_ref_dead' [-Werror=implicit-function-declaration]
  if (unlikely(percpu_ref_dead(&ctx->users)))
  ^
cc1: some warnings being treated as errors

Caused by commit 215e262f2aeb ("percpu: implement generic percpu
refcounting") from the percpu tree interacting with commit 4a375d552122
("aio: percpu ioctx refcount") from the akpm tree.

I removed the following patches from the akpm tree:

aio: reqs_active -> reqs_available
aio: percpu reqs_available
aio: percpu ioctx refcount
aio: use xchg() instead of completion_lock
block: prep work for batch completion
block-prep-work-for-batch-completion-fix-2
block-prep-work-for-batch-completion-fix-3
block-prep-work-for-batch-completion-fix-3-fix
block-prep-work-for-batch-completion-fix-99
block-prep-work-for-batch-completion-fix-4
block-prep-work-for-batch-completion-fix-101
block, aio: batch completion for bios/kiocbs
aio: fix kioctx not being freed after cancellation at exit time
block-aio-batch-completion-for-bios-kiocbs-fix
virtio-blk: convert to batch completion
mtip32xx: convert to batch completion
aio: convert the ioctx list to radix tree

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au