cregit-Linux how code gets into the kernel

Release 4.10 arch/alpha/include/asm/bitops.h

#ifndef _ALPHA_BITOPS_H

#define _ALPHA_BITOPS_H

#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif

#include <asm/compiler.h>
#include <asm/barrier.h>

/*
 * Copyright 1994, Linus Torvalds.
 */

/*
 * 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
 * was cleared before the operation and != 0 if it was not.
 *
 * To get proper branch prediction for the main line, we must branch
 * forward to code at the end of this object's .text section, then
 * branch back to restart the operation.
 *
 * bit 0 is the LSB of addr; bit 64 is the LSB of (addr+1).
 */


static inline void set_bit(unsigned long nr, volatile void * addr) { unsigned long temp; int *m = ((int *) addr) + (nr >> 5); __asm__ __volatile__( "1: ldl_l %0,%3\n" " bis %0,%2,%0\n" " stl_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (*m) :"Ir" (1UL << (nr & 31)), "m" (*m)); }

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pre-gitpre-git3995.12%480.00%
linus torvaldslinus torvalds24.88%120.00%
Total41100.00%5100.00%

/* * WARNING: non atomic version. */
static inline void __set_bit(unsigned long nr, volatile void * addr) { int *m = ((int *) addr) + (nr >> 5); *m |= 1 << (nr & 31); }

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static inline void clear_bit(unsigned long nr, volatile void * addr) { unsigned long temp; int *m = ((int *) addr) + (nr >> 5); __asm__ __volatile__( "1: ldl_l %0,%3\n" " bic %0,%2,%0\n" " stl_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (*m) :"Ir" (1UL << (nr & 31)), "m" (*m)); }

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richard hendersonrichard henderson12.44%120.00%
Total41100.00%5100.00%


static inline void clear_bit_unlock(unsigned long nr, volatile void * addr) { smp_mb(); clear_bit(nr, addr); }

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/* * WARNING: non atomic version. */
static __inline__ void __clear_bit(unsigned long nr, volatile void * addr) { int *m = ((int *) addr) + (nr >> 5); *m &= ~(1 << (nr & 31)); }

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linus torvaldslinus torvalds4389.58%150.00%
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static inline void __clear_bit_unlock(unsigned long nr, volatile void * addr) { smp_mb(); __clear_bit(nr, addr); }

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static inline void change_bit(unsigned long nr, volatile void * addr) { unsigned long temp; int *m = ((int *) addr) + (nr >> 5); __asm__ __volatile__( "1: ldl_l %0,%3\n" " xor %0,%2,%0\n" " stl_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (*m) :"Ir" (1UL << (nr & 31)), "m" (*m)); }

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pre-gitpre-git3892.68%375.00%
nick pigginnick piggin37.32%125.00%
Total41100.00%4100.00%

/* * WARNING: non atomic version. */
static __inline__ void __change_bit(unsigned long nr, volatile void * addr) { int *m = ((int *) addr) + (nr >> 5); *m ^= 1 << (nr & 31); }

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richard hendersonrichard henderson45100.00%1100.00%
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static inline int test_and_set_bit(unsigned long nr, volatile void *addr) { unsigned long oldbit; unsigned long temp; int *m = ((int *) addr) + (nr >> 5); __asm__ __volatile__( #ifdef CONFIG_SMP " mb\n" #endif "1: ldl_l %0,%4\n" " and %0,%3,%2\n" " bne %2,2f\n" " xor %0,%3,%0\n" " stl_c %0,%1\n" " beq %0,3f\n" "2:\n" #ifdef CONFIG_SMP " mb\n" #endif ".subsection 2\n" "3: br 1b\n" ".previous" :"=&r" (temp), "=m" (*m), "=&r" (oldbit) :"Ir" (1UL << (nr & 31)), "m" (*m) : "memory"); return oldbit != 0; }

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nick pigginnick piggin812.50%111.11%
linus torvaldslinus torvalds23.12%111.11%
Total64100.00%9100.00%


static inline int test_and_set_bit_lock(unsigned long nr, volatile void *addr) { unsigned long oldbit; unsigned long temp; int *m = ((int *) addr) + (nr >> 5); __asm__ __volatile__( "1: ldl_l %0,%4\n" " and %0,%3,%2\n" " bne %2,2f\n" " xor %0,%3,%0\n" " stl_c %0,%1\n" " beq %0,3f\n" "2:\n" #ifdef CONFIG_SMP " mb\n" #endif ".subsection 2\n" "3: br 1b\n" ".previous" :"=&r" (temp), "=m" (*m), "=&r" (oldbit) :"Ir" (1UL << (nr & 31)), "m" (*m) : "memory"); return oldbit != 0; }

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nick pigginnick piggin57100.00%1100.00%
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/* * WARNING: non atomic version. */
static inline int __test_and_set_bit(unsigned long nr, volatile void * addr) { unsigned long mask = 1 << (nr & 0x1f); int *m = ((int *) addr) + (nr >> 5); int old = *m; *m = old | mask; return (old & mask) != 0; }

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pre-gitpre-git6697.06%480.00%
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Total68100.00%5100.00%


static inline int test_and_clear_bit(unsigned long nr, volatile void * addr) { unsigned long oldbit; unsigned long temp; int *m = ((int *) addr) + (nr >> 5); __asm__ __volatile__( #ifdef CONFIG_SMP " mb\n" #endif "1: ldl_l %0,%4\n" " and %0,%3,%2\n" " beq %2,2f\n" " xor %0,%3,%0\n" " stl_c %0,%1\n" " beq %0,3f\n" "2:\n" #ifdef CONFIG_SMP " mb\n" #endif ".subsection 2\n" "3: br 1b\n" ".previous" :"=&r" (temp), "=m" (*m), "=&r" (oldbit) :"Ir" (1UL << (nr & 31)), "m" (*m) : "memory"); return oldbit != 0; }

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pre-gitpre-git5484.38%777.78%
nick pigginnick piggin812.50%111.11%
linus torvaldslinus torvalds23.12%111.11%
Total64100.00%9100.00%

/* * WARNING: non atomic version. */
static inline int __test_and_clear_bit(unsigned long nr, volatile void * addr) { unsigned long mask = 1 << (nr & 0x1f); int *m = ((int *) addr) + (nr >> 5); int old = *m; *m = old & ~mask; return (old & mask) != 0; }

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pre-gitpre-git6797.10%480.00%
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Total69100.00%5100.00%


static inline int test_and_change_bit(unsigned long nr, volatile void * addr) { unsigned long oldbit; unsigned long temp; int *m = ((int *) addr) + (nr >> 5); __asm__ __volatile__( #ifdef CONFIG_SMP " mb\n" #endif "1: ldl_l %0,%4\n" " and %0,%3,%2\n" " xor %0,%3,%0\n" " stl_c %0,%1\n" " beq %0,3f\n" #ifdef CONFIG_SMP " mb\n" #endif ".subsection 2\n" "3: br 1b\n" ".previous" :"=&r" (temp), "=m" (*m), "=&r" (oldbit) :"Ir" (1UL << (nr & 31)), "m" (*m) : "memory"); return oldbit != 0; }

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linus torvaldslinus torvalds3960.94%133.33%
richard hendersonrichard henderson1726.56%133.33%
nick pigginnick piggin812.50%133.33%
Total64100.00%3100.00%

/* * WARNING: non atomic version. */
static __inline__ int __test_and_change_bit(unsigned long nr, volatile void * addr) { unsigned long mask = 1 << (nr & 0x1f); int *m = ((int *) addr) + (nr >> 5); int old = *m; *m = old ^ mask; return (old & mask) != 0; }

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richard hendersonrichard henderson2942.65%114.29%
linus torvaldslinus torvalds11.47%114.29%
Total68100.00%7100.00%


static inline int test_bit(int nr, const volatile void * addr) { return (1UL & (((const int *) addr)[nr >> 5] >> (nr & 31))) != 0UL; }

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ivan kokshayskyivan kokshaysky12.22%112.50%
Total45100.00%8100.00%

/* * ffz = Find First Zero in word. Undefined if no zero exists, * so code should check against ~0UL first.. * * Do a binary search on the bits. Due to the nature of large * constants on the alpha, it is worthwhile to split the search. */
static inline unsigned long ffz_b(unsigned long x) { unsigned long sum, x1, x2, x4; x = ~x & -~x; /* set first 0 bit, clear others */ x1 = x & 0xAA; x2 = x & 0xCC; x4 = x & 0xF0; sum = x2 ? 2 : 0; sum += (x4 != 0) * 4; sum += (x1 != 0); return sum; }

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linus torvaldslinus torvalds11.27%120.00%
Total79100.00%5100.00%


static inline unsigned long ffz(unsigned long word) { #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67) /* Whee. EV67 can calculate it directly. */ return __kernel_cttz(~word); #else unsigned long bits, qofs, bofs; bits = __kernel_cmpbge(word, ~0UL); qofs = ffz_b(bits); bits = __kernel_extbl(word, qofs); bofs = ffz_b(bits); return qofs*8 + bofs; #endif }

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akinobu mitaakinobu mita22.41%110.00%
linus torvaldslinus torvalds11.20%110.00%
Total83100.00%10100.00%

/* * __ffs = Find First set bit in word. Undefined if no set bit exists. */
static inline unsigned long __ffs(unsigned long word) { #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67) /* Whee. EV67 can calculate it directly. */ return __kernel_cttz(word); #else unsigned long bits, qofs, bofs; bits = __kernel_cmpbge(0, word); qofs = ffz_b(bits); bits = __kernel_extbl(word, qofs); bofs = ffz_b(~bits); return qofs*8 + bofs; #endif }

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richard hendersonrichard henderson7895.12%360.00%
ivan kokshayskyivan kokshaysky22.44%120.00%
akinobu mitaakinobu mita22.44%120.00%
Total82100.00%5100.00%

#ifdef __KERNEL__ /* * ffs: find first bit set. This is defined the same way as * the libc and compiler builtin ffs routines, therefore * differs in spirit from the above __ffs. */
static inline int ffs(int word) { int result = __ffs(word) + 1; return word ? result : 0; }

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Total27100.00%4100.00%

/* * fls: find last bit set. */ #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
static inline int fls64(unsigned long word) { return 64 - __kernel_ctlz(word); }

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#else extern const unsigned char __flsm1_tab[256];
static inline int fls64(unsigned long x) { unsigned long t, a, r; t = __kernel_cmpbge (x, 0x0101010101010101UL); a = __flsm1_tab[t]; t = __kernel_extbl (x, a); r = a*8 + __flsm1_tab[t] + (x != 0); return r; }

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al viroal viro11.56%125.00%
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#endif
static inline unsigned long __fls(unsigned long x) { return fls64(x) - 1; }

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static inline int fls(int x) { return fls64((unsigned int) x); }

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/* * hweightN: returns the hamming weight (i.e. the number * of bits set) of a N-bit word */ #if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67) /* Whee. EV67 can calculate it directly. */
static inline unsigned long __arch_hweight64(unsigned long w) { return __kernel_ctpop(w); }

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linus torvaldslinus torvalds211.11%125.00%
peter zijlstrapeter zijlstra15.56%125.00%
Total18100.00%4100.00%


static inline unsigned int __arch_hweight32(unsigned int w) { return __arch_hweight64(w); }

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matt turnermatt turner15.56%125.00%
peter zijlstrapeter zijlstra15.56%125.00%
Total18100.00%4100.00%


static inline unsigned int __arch_hweight16(unsigned int w) { return __arch_hweight64(w & 0xffff); }

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Total20100.00%3100.00%


static inline unsigned int __arch_hweight8(unsigned int w) { return __arch_hweight64(w & 0xff); }

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Total20100.00%3100.00%

#else #include <asm-generic/bitops/arch_hweight.h> #endif #include <asm-generic/bitops/const_hweight.h> #endif /* __KERNEL__ */ #include <asm-generic/bitops/find.h> #ifdef __KERNEL__ /* * Every architecture must define this function. It's the fastest * way of searching a 100-bit bitmap. It's guaranteed that at least * one of the 100 bits is cleared. */
static inline unsigned long sched_find_first_bit(const unsigned long b[2]) { unsigned long b0, b1, ofs, tmp; b0 = b[0]; b1 = b[1]; ofs = (b0 ? 0 : 64); tmp = (b0 ? b0 : b1); return __ffs(tmp) + ofs; }

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richard hendersonrichard henderson5276.47%150.00%
matt turnermatt turner1623.53%150.00%
Total68100.00%2100.00%

#include <asm-generic/bitops/le.h> #include <asm-generic/bitops/ext2-atomic-setbit.h> #endif /* __KERNEL__ */ #endif /* _ALPHA_BITOPS_H */

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nick pigginnick piggin1369.35%25.00%
linus torvaldslinus torvalds1329.08%25.00%
ivan kokshayskyivan kokshaysky271.86%37.50%
alexander van heukelumalexander van heukelum201.38%12.50%
akinobu mitaakinobu mita191.31%410.00%
matt turnermatt turner181.24%25.00%
peter zijlstrapeter zijlstra100.69%12.50%
jiri slabyjiri slaby80.55%12.50%
al viroal viro10.07%12.50%
Total1454100.00%40100.00%
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