alloc_percpu: Use __get_cpu_ptr in block/

Impact: slight efficiency improvement on some archs.

Let's use __get_cpu_ptr and get_cpu_ptr now, rather than
per_cpu_ptr(..., smp_processor_id()).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
---
 block/blktrace.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/blktrace.c b/block/blktrace.c
--- a/block/blktrace.c
+++ b/block/blktrace.c
@@ -91,7 +91,7 @@ void __trace_note_message(struct blk_tra
 	char *buf;
 
 	local_irq_save(flags);
-	buf = per_cpu_ptr(bt->msg_data, smp_processor_id());
+	buf = __get_cpu_ptr(bt->msg_data);
 	va_start(args, fmt);
 	n = vscnprintf(buf, BLK_TN_MAX_MSG, fmt, args);
 	va_end(args);