Re: [PATCH 06/12] tools: sync small_const_nbits() macro with the kernel
From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Date: 2021-03-22 08:35:52
Also in:
linux-m68k, linux-sh, lkml
On 21/03/2021 22.54, Yury Norov wrote:
Move the macro from tools/include/asm-generic/bitsperlong.h to tools/include/linux/bitmap.h
The patch does it the other way around :)
quoted hunk ↗ jump to hunk
Signed-off-by: Yury Norov <yury.norov@gmail.com> --- tools/include/asm-generic/bitsperlong.h | 3 +++ tools/include/linux/bitmap.h | 3 --- 2 files changed, 3 insertions(+), 3 deletions(-)diff --git a/tools/include/asm-generic/bitsperlong.h b/tools/include/asm-generic/bitsperlong.h index 8f2283052333..f530da2506cc 100644 --- a/tools/include/asm-generic/bitsperlong.h +++ b/tools/include/asm-generic/bitsperlong.h@@ -18,4 +18,7 @@ #define BITS_PER_LONG_LONG 64 #endif +#define small_const_nbits(nbits) \ + (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG) +
Well, the movement is consistent with the kernel, but shouldn't the
definition also be updated to exclude constant-zero-size? It's not that
they exist or ever have, in tools/ or kernel proper, but just if some
day some oddball CONFIG_ combination ends up creating such a beast, I'd
rather not have code like
+ if (small_const_nbits(size)) {
+ unsigned long val = *addr & GENMASK(size - 1, 0);
blow up at run-time.
Other than that (and the above commit log typo), consider the series
Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>