Re: [PATCH next v2 2/5] minmax: Allow min()/max()/clamp() if the arguments have the same signedness.

From: kernel test robot
Date: Fri Jul 28 2023 - 22:01:55 EST


Hi David,

kernel test robot noticed the following build errors:

[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on linus/master crng-random/master v6.5-rc3 next-20230728]
[cannot apply to next-20230728]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/David-Laight/minmax-Add-min_unsigned-a-b-and-max_unsigned-a-b/20230728-225439
base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/r/bf92800b0c5445e2b2ca8c88e1f5e90f%40AcuMS.aculab.com
patch subject: [PATCH next v2 2/5] minmax: Allow min()/max()/clamp() if the arguments have the same signedness.
config: s390-randconfig-r044-20230728 (https://download.01.org/0day-ci/archive/20230729/202307290943.ODVeyeK6-lkp@xxxxxxxxx/config)
compiler: clang version 15.0.7 (https://github.com/llvm/llvm-project.git 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a)
reproduce: (https://download.01.org/0day-ci/archive/20230729/202307290943.ODVeyeK6-lkp@xxxxxxxxx/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202307290943.ODVeyeK6-lkp@xxxxxxxxx/

All errors (new ones prefixed by >>):

In file included from mm/percpu.c:73:
In file included from include/linux/memblock.h:13:
In file included from arch/s390/include/asm/dma.h:5:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __raw_readb(PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
#define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
#define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
^
In file included from mm/percpu.c:73:
In file included from include/linux/memblock.h:13:
In file included from arch/s390/include/asm/dma.h:5:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
#define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
#define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
^
In file included from mm/percpu.c:73:
In file included from include/linux/memblock.h:13:
In file included from arch/s390/include/asm/dma.h:5:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writeb(value, PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
>> mm/percpu.c:3102:10: error: static assertion expression is not an integral constant expression
base = min(ptr, base);
^~~~~~~~~~~~~~
include/linux/minmax.h:67:19: note: expanded from macro 'min'
#define min(x, y) __careful_cmp(min, x, y)
^~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:40:3: note: expanded from macro '__careful_cmp'
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:33:17: note: expanded from macro '__cmp_once'
static_assert(__types_ok(x, y), \
~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:23:2: note: expanded from macro '__types_ok'
(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
^
include/linux/build_bug.h:77:50: note: expanded from macro 'static_assert'
#define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr)
~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:78:56: note: expanded from macro '__static_assert'
#define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
^~~~
mm/percpu.c:3102:10: note: cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression
include/linux/minmax.h:67:19: note: expanded from macro 'min'
#define min(x, y) __careful_cmp(min, x, y)
^
include/linux/minmax.h:40:3: note: expanded from macro '__careful_cmp'
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
^
include/linux/minmax.h:33:17: note: expanded from macro '__cmp_once'
static_assert(__types_ok(x, y), \
^
include/linux/minmax.h:23:3: note: expanded from macro '__types_ok'
(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
^
include/linux/compiler.h:237:32: note: expanded from macro 'is_signed_type'
#define is_signed_type(type) (((type)(-1)) < (__force type)1)
^
12 warnings and 1 error generated.
--
In file included from mm/kmemleak.c:86:
In file included from include/linux/memblock.h:13:
In file included from arch/s390/include/asm/dma.h:5:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __raw_readb(PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
#define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
#define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
^
In file included from mm/kmemleak.c:86:
In file included from include/linux/memblock.h:13:
In file included from arch/s390/include/asm/dma.h:5:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
#define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
#define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
^
In file included from mm/kmemleak.c:86:
In file included from include/linux/memblock.h:13:
In file included from arch/s390/include/asm/dma.h:5:
In file included from include/linux/io.h:13:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writeb(value, PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
>> mm/kmemleak.c:1389:10: error: static assertion expression is not an integral constant expression
next = min(start + MAX_SCAN_SIZE, end);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:67:19: note: expanded from macro 'min'
#define min(x, y) __careful_cmp(min, x, y)
^~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:40:3: note: expanded from macro '__careful_cmp'
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:33:17: note: expanded from macro '__cmp_once'
static_assert(__types_ok(x, y), \
~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:23:2: note: expanded from macro '__types_ok'
(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
^
include/linux/build_bug.h:77:50: note: expanded from macro 'static_assert'
#define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr)
~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:78:56: note: expanded from macro '__static_assert'
#define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
^~~~
mm/kmemleak.c:1389:10: note: cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression
include/linux/minmax.h:67:19: note: expanded from macro 'min'
#define min(x, y) __careful_cmp(min, x, y)
^
include/linux/minmax.h:40:3: note: expanded from macro '__careful_cmp'
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
^
include/linux/minmax.h:33:17: note: expanded from macro '__cmp_once'
static_assert(__types_ok(x, y), \
^
include/linux/minmax.h:23:3: note: expanded from macro '__types_ok'
(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
^
include/linux/compiler.h:237:32: note: expanded from macro 'is_signed_type'
#define is_signed_type(type) (((type)(-1)) < (__force type)1)
^
mm/kmemleak.c:1429:11: error: static assertion expression is not an integral constant expression
next = min(start + MAX_SCAN_SIZE, end);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:67:19: note: expanded from macro 'min'
#define min(x, y) __careful_cmp(min, x, y)
^~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:40:3: note: expanded from macro '__careful_cmp'
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:33:17: note: expanded from macro '__cmp_once'
static_assert(__types_ok(x, y), \
~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:23:2: note: expanded from macro '__types_ok'
(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
^
include/linux/build_bug.h:77:50: note: expanded from macro 'static_assert'
#define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr)
~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:78:56: note: expanded from macro '__static_assert'
#define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
^~~~
mm/kmemleak.c:1429:11: note: cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression
include/linux/minmax.h:67:19: note: expanded from macro 'min'
#define min(x, y) __careful_cmp(min, x, y)
^
include/linux/minmax.h:40:3: note: expanded from macro '__careful_cmp'
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
^
include/linux/minmax.h:33:17: note: expanded from macro '__cmp_once'
static_assert(__types_ok(x, y), \
^
include/linux/minmax.h:23:3: note: expanded from macro '__types_ok'
(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
^
include/linux/compiler.h:237:32: note: expanded from macro 'is_signed_type'
#define is_signed_type(type) (((type)(-1)) < (__force type)1)
^
12 warnings and 2 errors generated.
--
In file included from crypto/skcipher.c:15:
In file included from include/crypto/scatterwalk.h:18:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __raw_readb(PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
#define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
#define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
^
In file included from crypto/skcipher.c:15:
In file included from include/crypto/scatterwalk.h:18:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
#define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
#define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
^
In file included from crypto/skcipher.c:15:
In file included from include/crypto/scatterwalk.h:18:
In file included from include/linux/scatterlist.h:9:
In file included from arch/s390/include/asm/io.h:78:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writeb(value, PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
readsl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesb(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesw(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
writesl(PCI_IOBASE + addr, buffer, count);
~~~~~~~~~~ ^
>> crypto/skcipher.c:80:9: error: static assertion expression is not an integral constant expression
return max(start, end_page);
^~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:74:19: note: expanded from macro 'max'
#define max(x, y) __careful_cmp(max, x, y)
^~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:40:3: note: expanded from macro '__careful_cmp'
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:33:17: note: expanded from macro '__cmp_once'
static_assert(__types_ok(x, y), \
~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:23:2: note: expanded from macro '__types_ok'
(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
^
include/linux/build_bug.h:77:50: note: expanded from macro 'static_assert'
#define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr)
~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/build_bug.h:78:56: note: expanded from macro '__static_assert'
#define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
^~~~
crypto/skcipher.c:80:9: note: cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression
include/linux/minmax.h:74:19: note: expanded from macro 'max'
#define max(x, y) __careful_cmp(max, x, y)
^
include/linux/minmax.h:40:3: note: expanded from macro '__careful_cmp'
__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
^
include/linux/minmax.h:33:17: note: expanded from macro '__cmp_once'
static_assert(__types_ok(x, y), \
^
include/linux/minmax.h:23:3: note: expanded from macro '__types_ok'
(is_signed_type(typeof(x)) == is_signed_type(typeof(y)))
^
include/linux/compiler.h:237:32: note: expanded from macro 'is_signed_type'
#define is_signed_type(type) (((type)(-1)) < (__force type)1)
^
12 warnings and 1 error generated.
..


vim +3102 mm/percpu.c

3c9a024fde58b08 Tejun Heo 2010-09-09 3022
3c9a024fde58b08 Tejun Heo 2010-09-09 3023 #if defined(BUILD_EMBED_FIRST_CHUNK)
66c3a75772247c3 Tejun Heo 2009-03-10 3024 /**
66c3a75772247c3 Tejun Heo 2009-03-10 3025 * pcpu_embed_first_chunk - embed the first percpu chunk into bootmem
66c3a75772247c3 Tejun Heo 2009-03-10 3026 * @reserved_size: the size of reserved percpu area in bytes
4ba6ce250e406b2 Tejun Heo 2010-06-27 3027 * @dyn_size: minimum free size for dynamic allocation in bytes
c8826dd538602d7 Tejun Heo 2009-08-14 3028 * @atom_size: allocation atom size
c8826dd538602d7 Tejun Heo 2009-08-14 3029 * @cpu_distance_fn: callback to determine distance between cpus, optional
1ca3fb3abd2b615 Kefeng Wang 2022-01-19 3030 * @cpu_to_nd_fn: callback to convert cpu to it's node, optional
66c3a75772247c3 Tejun Heo 2009-03-10 3031 *
66c3a75772247c3 Tejun Heo 2009-03-10 3032 * This is a helper to ease setting up embedded first percpu chunk and
66c3a75772247c3 Tejun Heo 2009-03-10 3033 * can be called where pcpu_setup_first_chunk() is expected.
66c3a75772247c3 Tejun Heo 2009-03-10 3034 *
66c3a75772247c3 Tejun Heo 2009-03-10 3035 * If this function is used to setup the first chunk, it is allocated
23f917169ef157a Kefeng Wang 2022-01-19 3036 * by calling pcpu_fc_alloc and used as-is without being mapped into
c8826dd538602d7 Tejun Heo 2009-08-14 3037 * vmalloc area. Allocations are always whole multiples of @atom_size
c8826dd538602d7 Tejun Heo 2009-08-14 3038 * aligned to @atom_size.
c8826dd538602d7 Tejun Heo 2009-08-14 3039 *
c8826dd538602d7 Tejun Heo 2009-08-14 3040 * This enables the first chunk to piggy back on the linear physical
c8826dd538602d7 Tejun Heo 2009-08-14 3041 * mapping which often uses larger page size. Please note that this
c8826dd538602d7 Tejun Heo 2009-08-14 3042 * can result in very sparse cpu->unit mapping on NUMA machines thus
c8826dd538602d7 Tejun Heo 2009-08-14 3043 * requiring large vmalloc address space. Don't use this allocator if
c8826dd538602d7 Tejun Heo 2009-08-14 3044 * vmalloc space is not orders of magnitude larger than distances
c8826dd538602d7 Tejun Heo 2009-08-14 3045 * between node memory addresses (ie. 32bit NUMA machines).
66c3a75772247c3 Tejun Heo 2009-03-10 3046 *
4ba6ce250e406b2 Tejun Heo 2010-06-27 3047 * @dyn_size specifies the minimum dynamic area size.
66c3a75772247c3 Tejun Heo 2009-03-10 3048 *
66c3a75772247c3 Tejun Heo 2009-03-10 3049 * If the needed size is smaller than the minimum or specified unit
23f917169ef157a Kefeng Wang 2022-01-19 3050 * size, the leftover is returned using pcpu_fc_free.
66c3a75772247c3 Tejun Heo 2009-03-10 3051 *
66c3a75772247c3 Tejun Heo 2009-03-10 3052 * RETURNS:
fb435d5233f8b6f Tejun Heo 2009-08-14 3053 * 0 on success, -errno on failure.
66c3a75772247c3 Tejun Heo 2009-03-10 3054 */
4ba6ce250e406b2 Tejun Heo 2010-06-27 3055 int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
c8826dd538602d7 Tejun Heo 2009-08-14 3056 size_t atom_size,
c8826dd538602d7 Tejun Heo 2009-08-14 3057 pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
23f917169ef157a Kefeng Wang 2022-01-19 3058 pcpu_fc_cpu_to_node_fn_t cpu_to_nd_fn)
66c3a75772247c3 Tejun Heo 2009-03-10 3059 {
c8826dd538602d7 Tejun Heo 2009-08-14 3060 void *base = (void *)ULONG_MAX;
c8826dd538602d7 Tejun Heo 2009-08-14 3061 void **areas = NULL;
fd1e8a1fe2b54df Tejun Heo 2009-08-14 3062 struct pcpu_alloc_info *ai;
93c76b6b2faaad7 zijun_hu 2016-10-05 3063 size_t size_sum, areas_size;
93c76b6b2faaad7 zijun_hu 2016-10-05 3064 unsigned long max_distance;
163fa23435cc9c7 Kefeng Wang 2019-07-03 3065 int group, i, highest_group, rc = 0;
66c3a75772247c3 Tejun Heo 2009-03-10 3066
c8826dd538602d7 Tejun Heo 2009-08-14 3067 ai = pcpu_build_alloc_info(reserved_size, dyn_size, atom_size,
c8826dd538602d7 Tejun Heo 2009-08-14 3068 cpu_distance_fn);
fd1e8a1fe2b54df Tejun Heo 2009-08-14 3069 if (IS_ERR(ai))
fd1e8a1fe2b54df Tejun Heo 2009-08-14 3070 return PTR_ERR(ai);
66c3a75772247c3 Tejun Heo 2009-03-10 3071
fd1e8a1fe2b54df Tejun Heo 2009-08-14 3072 size_sum = ai->static_size + ai->reserved_size + ai->dyn_size;
c8826dd538602d7 Tejun Heo 2009-08-14 3073 areas_size = PFN_ALIGN(ai->nr_groups * sizeof(void *));
fa8a7094ba1679b Tejun Heo 2009-06-22 3074
26fb3dae0a1ec78 Mike Rapoport 2019-03-11 3075 areas = memblock_alloc(areas_size, SMP_CACHE_BYTES);
c8826dd538602d7 Tejun Heo 2009-08-14 3076 if (!areas) {
fb435d5233f8b6f Tejun Heo 2009-08-14 3077 rc = -ENOMEM;
c8826dd538602d7 Tejun Heo 2009-08-14 3078 goto out_free;
fa8a7094ba1679b Tejun Heo 2009-06-22 3079 }
66c3a75772247c3 Tejun Heo 2009-03-10 3080
9b7396624a7b503 zijun_hu 2016-10-05 3081 /* allocate, copy and determine base address & max_distance */
9b7396624a7b503 zijun_hu 2016-10-05 3082 highest_group = 0;
c8826dd538602d7 Tejun Heo 2009-08-14 3083 for (group = 0; group < ai->nr_groups; group++) {
c8826dd538602d7 Tejun Heo 2009-08-14 3084 struct pcpu_group_info *gi = &ai->groups[group];
c8826dd538602d7 Tejun Heo 2009-08-14 3085 unsigned int cpu = NR_CPUS;
c8826dd538602d7 Tejun Heo 2009-08-14 3086 void *ptr;
c8826dd538602d7 Tejun Heo 2009-08-14 3087
c8826dd538602d7 Tejun Heo 2009-08-14 3088 for (i = 0; i < gi->nr_units && cpu == NR_CPUS; i++)
c8826dd538602d7 Tejun Heo 2009-08-14 3089 cpu = gi->cpu_map[i];
c8826dd538602d7 Tejun Heo 2009-08-14 3090 BUG_ON(cpu == NR_CPUS);
c8826dd538602d7 Tejun Heo 2009-08-14 3091
c8826dd538602d7 Tejun Heo 2009-08-14 3092 /* allocate space for the whole group */
23f917169ef157a Kefeng Wang 2022-01-19 3093 ptr = pcpu_fc_alloc(cpu, gi->nr_units * ai->unit_size, atom_size, cpu_to_nd_fn);
c8826dd538602d7 Tejun Heo 2009-08-14 3094 if (!ptr) {
c8826dd538602d7 Tejun Heo 2009-08-14 3095 rc = -ENOMEM;
c8826dd538602d7 Tejun Heo 2009-08-14 3096 goto out_free_areas;
c8826dd538602d7 Tejun Heo 2009-08-14 3097 }
f528f0b8e53d73b Catalin Marinas 2011-09-26 3098 /* kmemleak tracks the percpu allocations separately */
a317ebccaa36099 Patrick Wang 2022-07-05 3099 kmemleak_ignore_phys(__pa(ptr));
c8826dd538602d7 Tejun Heo 2009-08-14 3100 areas[group] = ptr;
c8826dd538602d7 Tejun Heo 2009-08-14 3101
c8826dd538602d7 Tejun Heo 2009-08-14 @3102 base = min(ptr, base);
9b7396624a7b503 zijun_hu 2016-10-05 3103 if (ptr > areas[highest_group])
9b7396624a7b503 zijun_hu 2016-10-05 3104 highest_group = group;
9b7396624a7b503 zijun_hu 2016-10-05 3105 }
9b7396624a7b503 zijun_hu 2016-10-05 3106 max_distance = areas[highest_group] - base;
9b7396624a7b503 zijun_hu 2016-10-05 3107 max_distance += ai->unit_size * ai->groups[highest_group].nr_units;
9b7396624a7b503 zijun_hu 2016-10-05 3108
9b7396624a7b503 zijun_hu 2016-10-05 3109 /* warn if maximum distance is further than 75% of vmalloc space */
9b7396624a7b503 zijun_hu 2016-10-05 3110 if (max_distance > VMALLOC_TOTAL * 3 / 4) {
9b7396624a7b503 zijun_hu 2016-10-05 3111 pr_warn("max_distance=0x%lx too large for vmalloc space 0x%lx\n",
9b7396624a7b503 zijun_hu 2016-10-05 3112 max_distance, VMALLOC_TOTAL);
9b7396624a7b503 zijun_hu 2016-10-05 3113 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
9b7396624a7b503 zijun_hu 2016-10-05 3114 /* and fail if we have fallback */
9b7396624a7b503 zijun_hu 2016-10-05 3115 rc = -EINVAL;
9b7396624a7b503 zijun_hu 2016-10-05 3116 goto out_free_areas;
9b7396624a7b503 zijun_hu 2016-10-05 3117 #endif
42b64281453249d Tejun Heo 2012-04-27 3118 }
42b64281453249d Tejun Heo 2012-04-27 3119
42b64281453249d Tejun Heo 2012-04-27 3120 /*
42b64281453249d Tejun Heo 2012-04-27 3121 * Copy data and free unused parts. This should happen after all
42b64281453249d Tejun Heo 2012-04-27 3122 * allocations are complete; otherwise, we may end up with
42b64281453249d Tejun Heo 2012-04-27 3123 * overlapping groups.
42b64281453249d Tejun Heo 2012-04-27 3124 */
42b64281453249d Tejun Heo 2012-04-27 3125 for (group = 0; group < ai->nr_groups; group++) {
42b64281453249d Tejun Heo 2012-04-27 3126 struct pcpu_group_info *gi = &ai->groups[group];
42b64281453249d Tejun Heo 2012-04-27 3127 void *ptr = areas[group];
66c3a75772247c3 Tejun Heo 2009-03-10 3128
c8826dd538602d7 Tejun Heo 2009-08-14 3129 for (i = 0; i < gi->nr_units; i++, ptr += ai->unit_size) {
c8826dd538602d7 Tejun Heo 2009-08-14 3130 if (gi->cpu_map[i] == NR_CPUS) {
c8826dd538602d7 Tejun Heo 2009-08-14 3131 /* unused unit, free whole */
23f917169ef157a Kefeng Wang 2022-01-19 3132 pcpu_fc_free(ptr, ai->unit_size);
c8826dd538602d7 Tejun Heo 2009-08-14 3133 continue;
c8826dd538602d7 Tejun Heo 2009-08-14 3134 }
c8826dd538602d7 Tejun Heo 2009-08-14 3135 /* copy and return the unused part */
fd1e8a1fe2b54df Tejun Heo 2009-08-14 3136 memcpy(ptr, __per_cpu_load, ai->static_size);
23f917169ef157a Kefeng Wang 2022-01-19 3137 pcpu_fc_free(ptr + size_sum, ai->unit_size - size_sum);
c8826dd538602d7 Tejun Heo 2009-08-14 3138 }
66c3a75772247c3 Tejun Heo 2009-03-10 3139 }
66c3a75772247c3 Tejun Heo 2009-03-10 3140
c8826dd538602d7 Tejun Heo 2009-08-14 3141 /* base address is now known, determine group base offsets */
6ea529a2037ce66 Tejun Heo 2009-09-24 3142 for (group = 0; group < ai->nr_groups; group++) {
c8826dd538602d7 Tejun Heo 2009-08-14 3143 ai->groups[group].base_offset = areas[group] - base;
6ea529a2037ce66 Tejun Heo 2009-09-24 3144 }
c8826dd538602d7 Tejun Heo 2009-08-14 3145
00206a69ee32f03 Matteo Croce 2019-03-18 3146 pr_info("Embedded %zu pages/cpu s%zu r%zu d%zu u%zu\n",
00206a69ee32f03 Matteo Croce 2019-03-18 3147 PFN_DOWN(size_sum), ai->static_size, ai->reserved_size,
fd1e8a1fe2b54df Tejun Heo 2009-08-14 3148 ai->dyn_size, ai->unit_size);
66c3a75772247c3 Tejun Heo 2009-03-10 3149
163fa23435cc9c7 Kefeng Wang 2019-07-03 3150 pcpu_setup_first_chunk(ai, base);
c8826dd538602d7 Tejun Heo 2009-08-14 3151 goto out_free;
c8826dd538602d7 Tejun Heo 2009-08-14 3152
c8826dd538602d7 Tejun Heo 2009-08-14 3153 out_free_areas:
c8826dd538602d7 Tejun Heo 2009-08-14 3154 for (group = 0; group < ai->nr_groups; group++)
f851c8d8583891a Michael Holzheu 2013-09-17 3155 if (areas[group])
23f917169ef157a Kefeng Wang 2022-01-19 3156 pcpu_fc_free(areas[group],
c8826dd538602d7 Tejun Heo 2009-08-14 3157 ai->groups[group].nr_units * ai->unit_size);
c8826dd538602d7 Tejun Heo 2009-08-14 3158 out_free:
fd1e8a1fe2b54df Tejun Heo 2009-08-14 3159 pcpu_free_alloc_info(ai);
c8826dd538602d7 Tejun Heo 2009-08-14 3160 if (areas)
4421cca0a3e4833 Mike Rapoport 2021-11-05 3161 memblock_free(areas, areas_size);
fb435d5233f8b6f Tejun Heo 2009-08-14 3162 return rc;
fa8a7094ba1679b Tejun Heo 2009-06-22 3163 }
3c9a024fde58b08 Tejun Heo 2010-09-09 3164 #endif /* BUILD_EMBED_FIRST_CHUNK */
d4b95f80399471e Tejun Heo 2009-07-04 3165

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki