drm/nouveau: replace ffsll with __ffs64

The ffsll function is a lot slower than the __ffs64 built-in which
compiles to a single instruction on 64-bit. It's also nice to avoid
custom versions of standard functions. Note that __ffs == ffs - 1.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_abi16.c b/drivers/gpu/drm/nouveau/nouveau_abi16.c
index 900fae01793e..b70111711be3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_abi16.c
+++ b/drivers/gpu/drm/nouveau/nouveau_abi16.c
@@ -270,8 +270,8 @@ nouveau_abi16_ioctl_channel_alloc(ABI16_IOCTL_ARGS)
                 return nouveau_abi16_put(abi16, -EINVAL);
 
         /* allocate "abi16 channel" data and make up a handle for it */
-        init->channel = ffsll(~abi16->handles);
-        if (!init->channel--)
+        init->channel = __ffs64(~abi16->handles);
+        if (~abi16->handles == 0)
                 return nouveau_abi16_put(abi16, -ENOSPC);
 
         chan = kzalloc(sizeof(*chan), GFP_KERNEL);