| 15,6 → 15,8 |
|---|
| #include <linux/compiler.h> |
| #include <asm/alternative.h> |
| |
| #define BIT_64(n) (U64_C(1) << (n)) |
| |
| /* |
| * These have to be done with inline assembly: that way the bit-setting |
| * is guaranteed to be atomic. All bit operations return 0 if the bit |
| 262,6 → 264,13 |
|---|
| * This operation is non-atomic and can be reordered. |
| * If two examples of this operation race, one can appear to succeed |
| * but actually fail. You must protect multiple accesses with a lock. |
| * |
| * Note: the operation is performed atomically with respect to |
| * the local CPU, but not other CPUs. Portable code should not |
| * rely on this behaviour. |
| * KVM relies on this behaviour on x86 for modifying memory that is also |
| * accessed from a hypervisor on the same CPU if running in a VM: don't change |
| * this without also updating arch/x86/kernel/kvm.c |
| */ |
| static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr) |
| { |
| 309,7 → 318,7 |
|---|
| static __always_inline int constant_test_bit(unsigned int nr, const volatile unsigned long *addr) |
| { |
| return ((1UL << (nr % BITS_PER_LONG)) & |
| (((unsigned long *)addr)[nr / BITS_PER_LONG])) != 0; |
| (addr[nr / BITS_PER_LONG])) != 0; |
| } |
| |
| static inline int variable_test_bit(int nr, volatile const unsigned long *addr) |
| 346,7 → 355,7 |
|---|
| */ |
| static inline unsigned long __ffs(unsigned long word) |
| { |
| asm("bsf %1,%0" |
| asm("rep; bsf %1,%0" |
| : "=r" (word) |
| : "rm" (word)); |
| return word; |
| 360,7 → 369,7 |
|---|
| */ |
| static inline unsigned long ffz(unsigned long word) |
| { |
| asm("bsf %1,%0" |
| asm("rep; bsf %1,%0" |
| : "=r" (word) |
| : "r" (~word)); |
| return word; |
| 380,6 → 389,8 |
|---|
| return word; |
| } |
| |
| #undef ADDR |
| |
| #ifdef __KERNEL__ |
| /** |
| * ffs - find first set bit in word |
| 398,7 → 409,7 |
|---|
| #ifdef CONFIG_X86_CMOV |
| asm("bsfl %1,%0\n\t" |
| "cmovzl %2,%0" |
| : "=r" (r) : "rm" (x), "r" (-1)); |
| : "=&r" (r) : "rm" (x), "r" (-1)); |
| #else |
| asm("bsfl %1,%0\n\t" |
| "jnz 1f\n\t" |