linux-stable/tools/include/linux/bits.h
Arnaldo Carvalho de Melo e3698b23ec tools headers: Synchronize linux/bits.h with the kernel sources
To pick up the changes in these csets:

  295bcca849 ("linux/bits.h: add compile time sanity check of GENMASK inputs")
  3945ff37d2 ("linux/bits.h: Extract common header for vDSO")

To address this tools/perf build warning:

  Warning: Kernel ABI header at 'tools/include/linux/bits.h' differs from latest version at 'include/linux/bits.h'
  diff -u tools/include/linux/bits.h include/linux/bits.h

This clashes with usage of userspace's static_assert(), that, at least
on glibc, is guarded by a ifnded/endif pair, do the same to our copy of
build_bug.h and avoid that diff in check_headers.sh so that we continue
checking for drifts with the kernel sources master copy.

This will all be tested with the set of build containers that includes
uCLibc, musl libc, lots of glibc versions in lots of distros and cross
build environments.

The tools/objtool, tools/bpf, etc were tested as well.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-14 11:40:05 -03:00

47 lines
1.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_BITS_H
#define __LINUX_BITS_H
#include <linux/const.h>
#include <vdso/bits.h>
#include <asm/bitsperlong.h>
#define BIT_ULL(nr) (ULL(1) << (nr))
#define BIT_MASK(nr) (UL(1) << ((nr) % BITS_PER_LONG))
#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
#define BIT_ULL_MASK(nr) (ULL(1) << ((nr) % BITS_PER_LONG_LONG))
#define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
#define BITS_PER_BYTE 8
/*
* Create a contiguous bitmask starting at bit position @l and ending at
* position @h. For example
* GENMASK_ULL(39, 21) gives us the 64bit vector 0x000000ffffe00000.
*/
#if !defined(__ASSEMBLY__) && \
(!defined(CONFIG_CC_IS_GCC) || CONFIG_GCC_VERSION >= 49000)
#include <linux/build_bug.h>
#define GENMASK_INPUT_CHECK(h, l) \
(BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
__builtin_constant_p((l) > (h)), (l) > (h), 0)))
#else
/*
* BUILD_BUG_ON_ZERO is not available in h files included from asm files,
* disable the input check if that is the case.
*/
#define GENMASK_INPUT_CHECK(h, l) 0
#endif
#define __GENMASK(h, l) \
(((~UL(0)) - (UL(1) << (l)) + 1) & \
(~UL(0) >> (BITS_PER_LONG - 1 - (h))))
#define GENMASK(h, l) \
(GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
#define __GENMASK_ULL(h, l) \
(((~ULL(0)) - (ULL(1) << (l)) + 1) & \
(~ULL(0) >> (BITS_PER_LONG_LONG - 1 - (h))))
#define GENMASK_ULL(h, l) \
(GENMASK_INPUT_CHECK(h, l) + __GENMASK_ULL(h, l))
#endif /* __LINUX_BITS_H */