@@ -1,7 +1,7 @@
#ifndef _ARM_ARM32_BITOPS_H
#define _ARM_ARM32_BITOPS_H
-#define flsl fls
+#define arch_flsl fls
/*
* Little endian assembly bitops. nr = 0 -> byte 0 bit 0.
@@ -22,17 +22,15 @@ static /*__*/always_inline unsigned long __ffs(unsigned long word)
*/
#define ffz(x) __ffs(~(x))
-static inline int flsl(unsigned long x)
+static inline int arch_flsl(unsigned long x)
{
uint64_t ret;
- if (__builtin_constant_p(x))
- return generic_flsl(x);
-
asm("clz\t%0, %1" : "=r" (ret) : "r" (x));
return BITS_PER_LONG - ret;
}
+#define arch_flsl arch_flsl
/* Based on linux/include/asm-generic/bitops/find.h */
@@ -145,17 +145,14 @@ static inline int test_bit(int nr, const volatile void *addr)
* the clz instruction for much better code efficiency.
*/
-static inline int fls(unsigned int x)
+static inline int arch_fls(unsigned int x)
{
int ret;
- if (__builtin_constant_p(x))
- return generic_fls(x);
-
asm("clz\t%"__OP32"0, %"__OP32"1" : "=r" (ret) : "r" (x));
return 32 - ret;
}
-
+#define arch_fls arch_fls
#define arch_ffs(x) ({ unsigned int __t = (x); fls(ISOLATE_LSB(__t)); })
#define arch_ffsl(x) ({ unsigned long __t = (x); flsl(ISOLATE_LSB(__t)); })
@@ -171,9 +171,6 @@ static inline int __test_and_clear_bit(int nr, volatile void *addr)
return (old & mask) != 0;
}
-#define flsl(x) generic_flsl(x)
-#define fls(x) generic_fls(x)
-
/* Based on linux/include/asm-generic/bitops/ffz.h */
/*
* ffz - find first zero in word.
@@ -438,7 +438,7 @@ static always_inline unsigned int arch_ffsl(unsigned long x)
*
* This is defined the same way as ffs.
*/
-static inline int flsl(unsigned long x)
+static always_inline int arch_flsl(unsigned long x)
{
long r;
@@ -448,8 +448,9 @@ static inline int flsl(unsigned long x)
"1:" : "=r" (r) : "rm" (x));
return (int)r+1;
}
+#define arch_flsl arch_flsl
-static inline int fls(unsigned int x)
+static always_inline int arch_fls(unsigned int x)
{
int r;
@@ -459,6 +460,7 @@ static inline int fls(unsigned int x)
"1:" : "=r" (r) : "rm" (x));
return r + 1;
}
+#define arch_fls arch_fls
/**
* hweightN - returns the hamming weight of a N-bit word
@@ -62,9 +62,31 @@ static void test_ffs(void)
CHECK(ffs64, (uint64_t)0x8000000000000000, 64);
}
+static void test_fls(void)
+{
+ /* unsigned int ffs(unsigned int) */
+ CHECK(fls, 1, 1);
+ CHECK(fls, 3, 2);
+ CHECK(fls, 3U << 30, 32);
+
+ /* unsigned int flsl(unsigned long) */
+ CHECK(flsl, 1, 1);
+ CHECK(flsl, 1UL << (BITS_PER_LONG - 1), BITS_PER_LONG);
+#if BITS_PER_LONG > 32
+ CHECK(flsl, 3UL << 32, 34);
+#endif
+
+ /* unsigned int fls64(uint64_t) */
+ CHECK(fls64, 1, 1);
+ CHECK(fls64, 0x00000000C0000000ULL, 32);
+ CHECK(fls64, 0x0000000180000000ULL, 33);
+ CHECK(fls64, 0xC000000000000000ULL, 64);
+}
+
static int __init cf_check test_bitops(void)
{
test_ffs();
+ test_fls();
return 0;
}
@@ -69,6 +69,30 @@ static inline int generic_flsl(unsigned long x)
#include <asm/bitops.h>
+static always_inline __pure int fls(unsigned int x)
+{
+ if (__builtin_constant_p(x))
+ return generic_fls(x);
+
+#ifndef arch_fls
+#define arch_fls generic_fls
+#endif
+
+ return arch_fls(x);
+}
+
+static always_inline __pure int flsl(unsigned long x)
+{
+ if (__builtin_constant_p(x))
+ return generic_flsl(x);
+
+#ifndef arch_flsl
+#define arch_flsl generic_flsl
+#endif
+
+ return arch_flsl(x);
+}
+
/*
* Find First Set bit. Bits are labelled from 1.
*/
Return type was left 'int' because of the following compilation error: ./include/xen/kernel.h:18:21: error: comparison of distinct pointer types lacks a cast [-Werror] 18 | (void) (&_x == &_y); \ | ^~ common/page_alloc.c:1843:34: note: in expansion of macro 'min' 1843 | unsigned int inc_order = min(MAX_ORDER, flsl(e - s) - 1); generic_fls{l} was used instead of __builtin_clz{l}(x) as if x is 0, the result in undefined. Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com> --- Changes in V6: - new patch for the patch series. --- xen/arch/arm/include/asm/arm32/bitops.h | 2 +- xen/arch/arm/include/asm/arm64/bitops.h | 6 ++---- xen/arch/arm/include/asm/bitops.h | 7 ++----- xen/arch/ppc/include/asm/bitops.h | 3 --- xen/arch/x86/include/asm/bitops.h | 6 ++++-- xen/common/bitops.c | 22 ++++++++++++++++++++++ xen/include/xen/bitops.h | 24 ++++++++++++++++++++++++ 7 files changed, 55 insertions(+), 15 deletions(-)