Re: [PATCH v8 1/4] bitops: Introduce the for_each_set_clump macro

From: kernel test robot
Date: Mon Jun 15 2020 - 12:48:53 EST

Hi Syed,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on 444fc5cde64330661bf59944c43844e7d4c2ccd8]

url: https://github.com/0day-ci/linux/commits/Syed-Nayyar-Waris/Introduce-the-for_each_set_clump-macro/20200615-205729
base: 444fc5cde64330661bf59944c43844e7d4c2ccd8
config: ia64-randconfig-r003-20200615 (attached as .config)
compiler: ia64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=ia64

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>, old ones prefixed by <<):

scripts/Makefile.build:59: 'arch/ia64/kernel/palinfo.ko' 'arch/ia64/kernel/mca_recovery.ko' 'arch/ia64/kernel/err_inject.ko' will not be built even though obj-m is specified.
scripts/Makefile.build:60: You cannot use subdir-y/m to visit a module Makefile. Use obj-y/m instead.
In file included from include/linux/bits.h:23,
from include/linux/bitops.h:5,
from include/linux/kernel.h:12,
from include/linux/list.h:9,
from include/linux/rculist.h:10,
from include/linux/sched/signal.h:5,
from arch/ia64/kernel/asm-offsets.c:10:
include/linux/bitmap.h: In function 'bitmap_get_value':
include/linux/bits.h:26:28: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
| ^
include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
| ^
include/linux/bits.h:39:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
39 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
| ^~~~~~~~~~~~~~~~~~~
>> include/linux/bitmap.h:590:35: note: in expansion of macro 'GENMASK'
590 | return (map[index] >> offset) & GENMASK(nbits - 1, 0);
| ^~~~~~~
include/linux/bits.h:26:40: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
| ^
include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
| ^
include/linux/bits.h:39:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
39 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
| ^~~~~~~~~~~~~~~~~~~
>> include/linux/bitmap.h:590:35: note: in expansion of macro 'GENMASK'
590 | return (map[index] >> offset) & GENMASK(nbits - 1, 0);
| ^~~~~~~
include/linux/bitmap.h: In function 'bitmap_set_value':
include/linux/bits.h:26:28: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
| ^
include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
| ^
include/linux/bits.h:39:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
39 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
| ^~~~~~~~~~~~~~~~~~~
include/linux/bitmap.h:630:11: note: in expansion of macro 'GENMASK'
630 | value &= GENMASK(nbits - 1, 0);
| ^~~~~~~
include/linux/bits.h:26:40: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
26 | __builtin_constant_p((l) > (h)), (l) > (h), 0)))
| ^
include/linux/build_bug.h:16:62: note: in definition of macro 'BUILD_BUG_ON_ZERO'
16 | #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
| ^
include/linux/bits.h:39:3: note: in expansion of macro 'GENMASK_INPUT_CHECK'
39 | (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
| ^~~~~~~~~~~~~~~~~~~
include/linux/bitmap.h:630:11: note: in expansion of macro 'GENMASK'
630 | value &= GENMASK(nbits - 1, 0);
| ^~~~~~~
In file included from arch/ia64/include/asm/pgtable.h:154,
from arch/ia64/include/asm/uaccess.h:40,
from include/linux/uaccess.h:11,
from include/linux/sched/task.h:11,
from include/linux/sched/signal.h:9,
from arch/ia64/kernel/asm-offsets.c:10:
arch/ia64/include/asm/mmu_context.h: In function 'reload_context':
arch/ia64/include/asm/mmu_context.h:137:41: warning: variable 'old_rr4' set but not used [-Wunused-but-set-variable]
137 | unsigned long rr0, rr1, rr2, rr3, rr4, old_rr4;
| ^~~~~~~
arch/ia64/kernel/asm-offsets.c: At top level:
arch/ia64/kernel/asm-offsets.c:23:6: warning: no previous prototype for 'foo' [-Wmissing-prototypes]
23 | void foo(void)
| ^~~
<stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp]

vim +/GENMASK +590 include/linux/bitmap.h

569
570 /**
571 * bitmap_get_value - get a value of n-bits from the memory region
572 * @map: address to the bitmap memory region
573 * @start: bit offset of the n-bit value
574 * @nbits: size of value in bits
575 *
576 * Returns value of nbits located at the @start bit offset within the @map
577 * memory region.
578 */
579 static inline unsigned long bitmap_get_value(const unsigned long *map,
580 unsigned long start,
581 unsigned long nbits)
582 {
583 const size_t index = BIT_WORD(start);
584 const unsigned long offset = start % BITS_PER_LONG;
585 const unsigned long ceiling = roundup(start + 1, BITS_PER_LONG);
586 const unsigned long space = ceiling - start;
587 unsigned long value_low, value_high;
588
589 if (space >= nbits)
> 590 return (map[index] >> offset) & GENMASK(nbits - 1, 0);
591 else {
592 value_low = map[index] & BITMAP_FIRST_WORD_MASK(start);
593 value_high = map[index + 1] & BITMAP_LAST_WORD_MASK(start + nbits);
594 return (value_low >> offset) | (value_high << space);
595 }
596 }
597

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
Description: application/gzip