[PATCH net-next v2 02/15] xtensa: remove the get_order() implementation

From: Yunsheng Lin
Date: Mon Apr 15 2024 - 09:30:41 EST


As the get_order() implemented by xtensa supporting 'nsau'
instruction seems be the same as the generic implementation
in include/asm-generic/getorder.h when size is not a constant
value as the generic implementation calling the fls*() is also
utilizing the 'nsau' instruction for xtensa.

So remove the get_order() implemented by xtensa, as using the
generic implementation may enable the compiler to do the
computing when size is a constant value instead of runtime
computing and enable the using of get_order() in BUILD_BUG_ON()
macro.

Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
---
arch/xtensa/include/asm/page.h | 18 ------------------
1 file changed, 18 deletions(-)

diff --git a/arch/xtensa/include/asm/page.h b/arch/xtensa/include/asm/page.h
index 4db56ef052d2..8665d57991dd 100644
--- a/arch/xtensa/include/asm/page.h
+++ b/arch/xtensa/include/asm/page.h
@@ -109,26 +109,8 @@ typedef struct page *pgtable_t;
#define __pgd(x) ((pgd_t) { (x) } )
#define __pgprot(x) ((pgprot_t) { (x) } )

-/*
- * Pure 2^n version of get_order
- * Use 'nsau' instructions if supported by the processor or the generic version.
- */
-
-#if XCHAL_HAVE_NSA
-
-static inline __attribute_const__ int get_order(unsigned long size)
-{
- int lz;
- asm ("nsau %0, %1" : "=r" (lz) : "r" ((size - 1) >> PAGE_SHIFT));
- return 32 - lz;
-}
-
-#else
-
# include <asm-generic/getorder.h>

-#endif
-
struct page;
struct vm_area_struct;
extern void clear_page(void *page);
--
2.33.0