[PATCH] NDS32: perf_event_cpu: fix 2 build errors

[Randy Dunlap]

../arch/nds32/kernel/perf_event_cpu.c: In function 'unwind_frame_kernel':
../arch/nds32/include/asm/current.h:10:13: error: '$r25' undeclared (first use in this function)
   10 | #define tsk $r25
../arch/nds32/kernel/perf_event_cpu.c:1255:50: note: in expansion of macro 'tsk'
 1255 |                                                 (tsk, &graph, frame->lp, NULL);

../arch/nds32/kernel/perf_event_cpu.c:1257:27: error: assignment to 'long unsigned int' from 'long unsigned int *' makes integer from pointer without a cast [-Werror=int-conversion]
 1257 |                 frame->sp = ((unsigned long *)frame->sp) + 1;

For $r25, use the register function for current() instead.

Fixes: c8b34461705e ("nds32: Add perf call-graph support.")
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Nickhu <nickhu@xxxxxxxxxxxxx>
Cc: Greentime Hu <green.hu@xxxxxxxxx>
Cc: Vincent Chen <deanbo422@xxxxxxxxx>
---
Please check the frame->sp cast/arithmetic.

 arch/nds32/kernel/perf_event_cpu.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- linux-next-20210917.orig/arch/nds32/kernel/perf_event_cpu.c
+++ linux-next-20210917/arch/nds32/kernel/perf_event_cpu.c
@@ -1252,9 +1252,9 @@ static int unwind_frame_kernel(struct st
 		 */
 		if (__kernel_text_address(frame->lp))
 			frame->lp = ftrace_graph_ret_addr
-						(tsk, &graph, frame->lp, NULL);
+					(current, &graph, frame->lp, NULL);
 
-		frame->sp = ((unsigned long *)frame->sp) + 1;
+		frame->sp = (unsigned long)(((unsigned long *)frame->sp)) + 1;
 
 		return 0;
 	} else {