powerpc/signal: Remove get_clean_sp()

get_clean_sp() is only used once in kernel/signal.c .

GCC is smart enough to see that x & 0xffffffff is a nop
calculation on PPC32, no need of a special PPC32 trivial version.

Include the logic from the PPC64 version of get_clean_sp() directly
in get_sigframe().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/13ef6510ce30a4867e043157b93af5bb8c67fb3b.1597770847.git.christophe.leroy@csgroup.eu

arch/powerpc/include/asm/processor.h

@@ -391,20 +391,6 @@ static inline void prefetchw(const void *x)
 
 #define HAVE_ARCH_PICK_MMAP_LAYOUT
 
-#ifdef CONFIG_PPC64
-static inline unsigned long get_clean_sp(unsigned long sp, int is_32)
-{
-	if (is_32)
-		return sp & 0x0ffffffffUL;
-	return sp;
-}
-#else
-static inline unsigned long get_clean_sp(unsigned long sp, int is_32)
-{
-	return sp;
-}
-#endif
-
 /* asm stubs */
 extern unsigned long isa300_idle_stop_noloss(unsigned long psscr_val);
 extern unsigned long isa300_idle_stop_mayloss(unsigned long psscr_val);

arch/powerpc/kernel/signal.c

@@ -150,7 +150,10 @@ void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
         unsigned long oldsp, newsp;
 
         /* Default to using normal stack */
-        oldsp = get_clean_sp(sp, is_32);
+	if (is_32)
+		oldsp = sp & 0x0ffffffffUL;
+	else
+		oldsp = sp;
 	oldsp = sigsp(oldsp, ksig);
 	newsp = (oldsp - frame_size) & ~0xFUL;