On Sat, Jan 30, 2021 at 11:17:15AM -0800, Yury Norov wrote:
BITMAP_{LAST,FIRST}_WORD_MASK() in linux/bitmap.h duplicates the
functionality of GENMASK(). The scope of there macros is wider than just
bitmap. This patch defines 4 new macros: BITS_FIRST(), BITS_LAST(),
BITS_FIRST_MASK() and BITS_LAST_MASK() in linux/bits.h on top of GENMASK()
and replaces BITMAP_{LAST,FIRST}_WORD_MASK() to avoid duplication and
increases scope of the macros.
...
include/linux/bitmap.h | 27 ++++++++++++---------------
include/linux/bits.h | 6 ++++++
include/linux/cpumask.h | 8 ++++----
include/linux/netdev_features.h | 2 +-
include/linux/nodemask.h | 2 +-
lib/bitmap.c | 26 +++++++++++++-------------
lib/find_bit.c | 4 ++--
lib/genalloc.c | 8 ++++----
Answering to your reply. I meant to split the below to a separate patch.
tools/include/linux/bitmap.h | 20 ++++++--------------
tools/include/linux/bits.h | 6 ++++++
tools/lib/bitmap.c | 6 +++---
tools/lib/find_bit.c | 2 +-
tools/testing/radix-tree/bitmap.c | 4 ++--
...
+#define BITS_FIRST(nr) GENMASK((nr), 0)
+#define BITS_LAST(nr) GENMASK(BITS_PER_LONG - 1, (nr))
+
+#define BITS_FIRST_MASK(nr) BITS_FIRST((nr) % BITS_PER_LONG)
+#define BITS_LAST_MASK(nr) BITS_LAST((nr) % BITS_PER_LONG)
Any pointers to the difference in generated code for popular architectures
(x86. x86_64, arm, aarch64, ppc, ppc64)?
--
With Best Regards,
Andy Shevchenko
