ARC: Atomic/bitops/cmpxchg/barriers

This covers the UP / SMP (with no hardware assist for atomic r-m-w) as
well as ARC700 LLOCK/SCOND insns based.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This commit is contained in:
Vineet Gupta 2013-01-18 15:12:16 +05:30
parent ac4c244d4e
commit 14e968bad7
5 changed files with 967 additions and 0 deletions

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/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _ASM_ARC_ATOMIC_H
#define _ASM_ARC_ATOMIC_H
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/compiler.h>
#include <asm/cmpxchg.h>
#include <asm/barrier.h>
#include <asm/smp.h>
#define atomic_read(v) ((v)->counter)
#ifdef CONFIG_ARC_HAS_LLSC
#define atomic_set(v, i) (((v)->counter) = (i))
static inline void atomic_add(int i, atomic_t *v)
{
unsigned int temp;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" add %0, %0, %2 \n"
" scond %0, [%1] \n"
" bnz 1b \n"
: "=&r"(temp) /* Early clobber, to prevent reg reuse */
: "r"(&v->counter), "ir"(i)
: "cc");
}
static inline void atomic_sub(int i, atomic_t *v)
{
unsigned int temp;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" sub %0, %0, %2 \n"
" scond %0, [%1] \n"
" bnz 1b \n"
: "=&r"(temp)
: "r"(&v->counter), "ir"(i)
: "cc");
}
/* add and also return the new value */
static inline int atomic_add_return(int i, atomic_t *v)
{
unsigned int temp;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" add %0, %0, %2 \n"
" scond %0, [%1] \n"
" bnz 1b \n"
: "=&r"(temp)
: "r"(&v->counter), "ir"(i)
: "cc");
return temp;
}
static inline int atomic_sub_return(int i, atomic_t *v)
{
unsigned int temp;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" sub %0, %0, %2 \n"
" scond %0, [%1] \n"
" bnz 1b \n"
: "=&r"(temp)
: "r"(&v->counter), "ir"(i)
: "cc");
return temp;
}
static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
{
unsigned int temp;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" bic %0, %0, %2 \n"
" scond %0, [%1] \n"
" bnz 1b \n"
: "=&r"(temp)
: "r"(addr), "ir"(mask)
: "cc");
}
#else /* !CONFIG_ARC_HAS_LLSC */
#ifndef CONFIG_SMP
/* violating atomic_xxx API locking protocol in UP for optimization sake */
#define atomic_set(v, i) (((v)->counter) = (i))
#else
static inline void atomic_set(atomic_t *v, int i)
{
/*
* Independent of hardware support, all of the atomic_xxx() APIs need
* to follow the same locking rules to make sure that a "hardware"
* atomic insn (e.g. LD) doesn't clobber an "emulated" atomic insn
* sequence
*
* Thus atomic_set() despite being 1 insn (and seemingly atomic)
* requires the locking.
*/
unsigned long flags;
atomic_ops_lock(flags);
v->counter = i;
atomic_ops_unlock(flags);
}
#endif
/*
* Non hardware assisted Atomic-R-M-W
* Locking would change to irq-disabling only (UP) and spinlocks (SMP)
*/
static inline void atomic_add(int i, atomic_t *v)
{
unsigned long flags;
atomic_ops_lock(flags);
v->counter += i;
atomic_ops_unlock(flags);
}
static inline void atomic_sub(int i, atomic_t *v)
{
unsigned long flags;
atomic_ops_lock(flags);
v->counter -= i;
atomic_ops_unlock(flags);
}
static inline int atomic_add_return(int i, atomic_t *v)
{
unsigned long flags;
unsigned long temp;
atomic_ops_lock(flags);
temp = v->counter;
temp += i;
v->counter = temp;
atomic_ops_unlock(flags);
return temp;
}
static inline int atomic_sub_return(int i, atomic_t *v)
{
unsigned long flags;
unsigned long temp;
atomic_ops_lock(flags);
temp = v->counter;
temp -= i;
v->counter = temp;
atomic_ops_unlock(flags);
return temp;
}
static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
{
unsigned long flags;
atomic_ops_lock(flags);
*addr &= ~mask;
atomic_ops_unlock(flags);
}
#endif /* !CONFIG_ARC_HAS_LLSC */
/**
* __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
* Returns the old value of @v
*/
#define __atomic_add_unless(v, a, u) \
({ \
int c, old; \
c = atomic_read(v); \
while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c)\
c = old; \
c; \
})
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
#define atomic_inc(v) atomic_add(1, v)
#define atomic_dec(v) atomic_sub(1, v)
#define atomic_inc_and_test(v) (atomic_add_return(1, v) == 0)
#define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)
#define atomic_inc_return(v) atomic_add_return(1, (v))
#define atomic_dec_return(v) atomic_sub_return(1, (v))
#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
#define atomic_add_negative(i, v) (atomic_add_return(i, v) < 0)
#define ATOMIC_INIT(i) { (i) }
#include <asm-generic/atomic64.h>
#endif
#endif
#endif

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/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __ASM_BARRIER_H
#define __ASM_BARRIER_H
#ifndef __ASSEMBLY__
/* TODO-vineetg: Need to see what this does, don't we need sync anywhere */
#define mb() __asm__ __volatile__ ("" : : : "memory")
#define rmb() mb()
#define wmb() mb()
#define set_mb(var, value) do { var = value; mb(); } while (0)
#define set_wmb(var, value) do { var = value; wmb(); } while (0)
#define read_barrier_depends() mb()
/* TODO-vineetg verify the correctness of macros here */
#ifdef CONFIG_SMP
#define smp_mb() mb()
#define smp_rmb() rmb()
#define smp_wmb() wmb()
#else
#define smp_mb() barrier()
#define smp_rmb() barrier()
#define smp_wmb() barrier()
#endif
#define smp_mb__before_atomic_dec() barrier()
#define smp_mb__after_atomic_dec() barrier()
#define smp_mb__before_atomic_inc() barrier()
#define smp_mb__after_atomic_inc() barrier()
#define smp_read_barrier_depends() do { } while (0)
#endif
#endif

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/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _ASM_BITOPS_H
#define _ASM_BITOPS_H
#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/compiler.h>
/*
* Hardware assisted read-modify-write using ARC700 LLOCK/SCOND insns.
* The Kconfig glue ensures that in SMP, this is only set if the container
* SoC/platform has cross-core coherent LLOCK/SCOND
*/
#if defined(CONFIG_ARC_HAS_LLSC)
static inline void set_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned int temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" bset %0, %0, %2 \n"
" scond %0, [%1] \n"
" bnz 1b \n"
: "=&r"(temp)
: "r"(m), "ir"(nr)
: "cc");
}
static inline void clear_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned int temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" bclr %0, %0, %2 \n"
" scond %0, [%1] \n"
" bnz 1b \n"
: "=&r"(temp)
: "r"(m), "ir"(nr)
: "cc");
}
static inline void change_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned int temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" bxor %0, %0, %2 \n"
" scond %0, [%1] \n"
" bnz 1b \n"
: "=&r"(temp)
: "r"(m), "ir"(nr)
: "cc");
}
/*
* Semantically:
* Test the bit
* if clear
* set it and return 0 (old value)
* else
* return 1 (old value).
*
* Since ARC lacks a equivalent h/w primitive, the bit is set unconditionally
* and the old value of bit is returned
*/
static inline int test_and_set_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long old, temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
__asm__ __volatile__(
"1: llock %0, [%2] \n"
" bset %1, %0, %3 \n"
" scond %1, [%2] \n"
" bnz 1b \n"
: "=&r"(old), "=&r"(temp)
: "r"(m), "ir"(nr)
: "cc");
return (old & (1 << nr)) != 0;
}
static inline int
test_and_clear_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned int old, temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
__asm__ __volatile__(
"1: llock %0, [%2] \n"
" bclr %1, %0, %3 \n"
" scond %1, [%2] \n"
" bnz 1b \n"
: "=&r"(old), "=&r"(temp)
: "r"(m), "ir"(nr)
: "cc");
return (old & (1 << nr)) != 0;
}
static inline int
test_and_change_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned int old, temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
__asm__ __volatile__(
"1: llock %0, [%2] \n"
" bxor %1, %0, %3 \n"
" scond %1, [%2] \n"
" bnz 1b \n"
: "=&r"(old), "=&r"(temp)
: "r"(m), "ir"(nr)
: "cc");
return (old & (1 << nr)) != 0;
}
#else /* !CONFIG_ARC_HAS_LLSC */
#include <asm/smp.h>
/*
* Non hardware assisted Atomic-R-M-W
* Locking would change to irq-disabling only (UP) and spinlocks (SMP)
*
* There's "significant" micro-optimization in writing our own variants of
* bitops (over generic variants)
*
* (1) The generic APIs have "signed" @nr while we have it "unsigned"
* This avoids extra code to be generated for pointer arithmatic, since
* is "not sure" that index is NOT -ve
* (2) Utilize the fact that ARCompact bit fidding insn (BSET/BCLR/ASL) etc
* only consider bottom 5 bits of @nr, so NO need to mask them off.
* (GCC Quirk: however for constant @nr we still need to do the masking
* at compile time)
*/
static inline void set_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long temp, flags;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
bitops_lock(flags);
temp = *m;
*m = temp | (1UL << nr);
bitops_unlock(flags);
}
static inline void clear_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long temp, flags;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
bitops_lock(flags);
temp = *m;
*m = temp & ~(1UL << nr);
bitops_unlock(flags);
}
static inline void change_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long temp, flags;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
bitops_lock(flags);
temp = *m;
*m = temp ^ (1UL << nr);
bitops_unlock(flags);
}
static inline int test_and_set_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long old, flags;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
bitops_lock(flags);
old = *m;
*m = old | (1 << nr);
bitops_unlock(flags);
return (old & (1 << nr)) != 0;
}
static inline int
test_and_clear_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long old, flags;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
bitops_lock(flags);
old = *m;
*m = old & ~(1 << nr);
bitops_unlock(flags);
return (old & (1 << nr)) != 0;
}
static inline int
test_and_change_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long old, flags;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
bitops_lock(flags);
old = *m;
*m = old ^ (1 << nr);
bitops_unlock(flags);
return (old & (1 << nr)) != 0;
}
#endif /* CONFIG_ARC_HAS_LLSC */
/***************************************
* Non atomic variants
**************************************/
static inline void __set_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
temp = *m;
*m = temp | (1UL << nr);
}
static inline void __clear_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
temp = *m;
*m = temp & ~(1UL << nr);
}
static inline void __change_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long temp;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
temp = *m;
*m = temp ^ (1UL << nr);
}
static inline int
__test_and_set_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long old;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
old = *m;
*m = old | (1 << nr);
return (old & (1 << nr)) != 0;
}
static inline int
__test_and_clear_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long old;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
old = *m;
*m = old & ~(1 << nr);
return (old & (1 << nr)) != 0;
}
static inline int
__test_and_change_bit(unsigned long nr, volatile unsigned long *m)
{
unsigned long old;
m += nr >> 5;
if (__builtin_constant_p(nr))
nr &= 0x1f;
old = *m;
*m = old ^ (1 << nr);
return (old & (1 << nr)) != 0;
}
/*
* This routine doesn't need to be atomic.
*/
static inline int
__constant_test_bit(unsigned int nr, const volatile unsigned long *addr)
{
return ((1UL << (nr & 31)) &
(((const volatile unsigned int *)addr)[nr >> 5])) != 0;
}
static inline int
__test_bit(unsigned int nr, const volatile unsigned long *addr)
{
unsigned long mask;
addr += nr >> 5;
/* ARC700 only considers 5 bits in bit-fiddling insn */
mask = 1 << nr;
return ((mask & *addr) != 0);
}
#define test_bit(nr, addr) (__builtin_constant_p(nr) ? \
__constant_test_bit((nr), (addr)) : \
__test_bit((nr), (addr)))
/*
* Count the number of zeros, starting from MSB
* Helper for fls( ) friends
* This is a pure count, so (1-32) or (0-31) doesn't apply
* It could be 0 to 32, based on num of 0's in there
* clz(0x8000_0000) = 0, clz(0xFFFF_FFFF)=0, clz(0) = 32, clz(1) = 31
*/
static inline __attribute__ ((const)) int clz(unsigned int x)
{
unsigned int res;
__asm__ __volatile__(
" norm.f %0, %1 \n"
" mov.n %0, 0 \n"
" add.p %0, %0, 1 \n"
: "=r"(res)
: "r"(x)
: "cc");
return res;
}
static inline int constant_fls(int x)
{
int r = 32;
if (!x)
return 0;
if (!(x & 0xffff0000u)) {
x <<= 16;
r -= 16;
}
if (!(x & 0xff000000u)) {
x <<= 8;
r -= 8;
}
if (!(x & 0xf0000000u)) {
x <<= 4;
r -= 4;
}
if (!(x & 0xc0000000u)) {
x <<= 2;
r -= 2;
}
if (!(x & 0x80000000u)) {
x <<= 1;
r -= 1;
}
return r;
}
/*
* fls = Find Last Set in word
* @result: [1-32]
* fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0
*/
static inline __attribute__ ((const)) int fls(unsigned long x)
{
if (__builtin_constant_p(x))
return constant_fls(x);
return 32 - clz(x);
}
/*
* __fls: Similar to fls, but zero based (0-31)
*/
static inline __attribute__ ((const)) int __fls(unsigned long x)
{
if (!x)
return 0;
else
return fls(x) - 1;
}
/*
* ffs = Find First Set in word (LSB to MSB)
* @result: [1-32], 0 if all 0's
*/
#define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
/*
* __ffs: Similar to ffs, but zero based (0-31)
*/
static inline __attribute__ ((const)) int __ffs(unsigned long word)
{
if (!word)
return word;
return ffs(word) - 1;
}
/*
* ffz = Find First Zero in word.
* @return:[0-31], 32 if all 1's
*/
#define ffz(x) __ffs(~(x))
/* TODO does this affect uni-processor code */
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/sched.h>
#include <asm-generic/bitops/lock.h>
#include <asm-generic/bitops/find.h>
#include <asm-generic/bitops/le.h>
#include <asm-generic/bitops/ext2-atomic-setbit.h>
#endif /* !__ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif

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/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __ASM_ARC_CMPXCHG_H
#define __ASM_ARC_CMPXCHG_H
#include <linux/types.h>
#include <asm/smp.h>
#ifdef CONFIG_ARC_HAS_LLSC
static inline unsigned long
__cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new)
{
unsigned long prev;
__asm__ __volatile__(
"1: llock %0, [%1] \n"
" brne %0, %2, 2f \n"
" scond %3, [%1] \n"
" bnz 1b \n"
"2: \n"
: "=&r"(prev)
: "r"(ptr), "ir"(expected),
"r"(new) /* can't be "ir". scond can't take limm for "b" */
: "cc");
return prev;
}
#else
static inline unsigned long
__cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new)
{
unsigned long flags;
int prev;
volatile unsigned long *p = ptr;
atomic_ops_lock(flags);
prev = *p;
if (prev == expected)
*p = new;
atomic_ops_unlock(flags);
return prev;
}
#endif /* CONFIG_ARC_HAS_LLSC */
#define cmpxchg(ptr, o, n) ((typeof(*(ptr)))__cmpxchg((ptr), \
(unsigned long)(o), (unsigned long)(n)))
/*
* Since not supported natively, ARC cmpxchg() uses atomic_ops_lock (UP/SMP)
* just to gaurantee semantics.
* atomic_cmpxchg() needs to use the same locks as it's other atomic siblings
* which also happens to be atomic_ops_lock.
*
* Thus despite semantically being different, implementation of atomic_cmpxchg()
* is same as cmpxchg().
*/
#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
/*
* xchg (reg with memory) based on "Native atomic" EX insn
*/
static inline unsigned long __xchg(unsigned long val, volatile void *ptr,
int size)
{
extern unsigned long __xchg_bad_pointer(void);
switch (size) {
case 4:
__asm__ __volatile__(
" ex %0, [%1] \n"
: "+r"(val)
: "r"(ptr)
: "memory");
return val;
}
return __xchg_bad_pointer();
}
#define _xchg(ptr, with) ((typeof(*(ptr)))__xchg((unsigned long)(with), (ptr), \
sizeof(*(ptr))))
/*
* On ARC700, EX insn is inherently atomic, so by default "vanilla" xchg() need
* not require any locking. However there's a quirk.
* ARC lacks native CMPXCHG, thus emulated (see above), using external locking -
* incidently it "reuses" the same atomic_ops_lock used by atomic APIs.
* Now, llist code uses cmpxchg() and xchg() on same data, so xchg() needs to
* abide by same serializing rules, thus ends up using atomic_ops_lock as well.
*
* This however is only relevant if SMP and/or ARC lacks LLSC
* if (UP or LLSC)
* xchg doesn't need serialization
* else <==> !(UP or LLSC) <==> (!UP and !LLSC) <==> (SMP and !LLSC)
* xchg needs serialization
*/
#if !defined(CONFIG_ARC_HAS_LLSC) && defined(CONFIG_SMP)
#define xchg(ptr, with) \
({ \
unsigned long flags; \
typeof(*(ptr)) old_val; \
\
atomic_ops_lock(flags); \
old_val = _xchg(ptr, with); \
atomic_ops_unlock(flags); \
old_val; \
})
#else
#define xchg(ptr, with) _xchg(ptr, with)
#endif
/*
* "atomic" variant of xchg()
* REQ: It needs to follow the same serialization rules as other atomic_xxx()
* Since xchg() doesn't always do that, it would seem that following defintion
* is incorrect. But here's the rationale:
* SMP : Even xchg() takes the atomic_ops_lock, so OK.
* LLSC: atomic_ops_lock are not relevent at all (even if SMP, since LLSC
* is natively "SMP safe", no serialization required).
* UP : other atomics disable IRQ, so no way a difft ctxt atomic_xchg()
* could clobber them. atomic_xchg() itself would be 1 insn, so it
* can't be clobbered by others. Thus no serialization required when
* atomic_xchg is involved.
*/
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
#endif

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/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __ASM_ARC_SMP_H
#define __ASM_ARC_SMP_H
/*
* ARC700 doesn't support atomic Read-Modify-Write ops.
* Originally Interrupts had to be disabled around code to gaurantee atomicity.
* The LLOCK/SCOND insns allow writing interrupt-hassle-free based atomic ops
* based on retry-if-irq-in-atomic (with hardware assist).
* However despite these, we provide the IRQ disabling variant
*
* (1) These insn were introduced only in 4.10 release. So for older released
* support needed.
*/
#ifndef CONFIG_ARC_HAS_LLSC
#include <linux/irqflags.h>
#define atomic_ops_lock(flags) local_irq_save(flags)
#define atomic_ops_unlock(flags) local_irq_restore(flags)
#define bitops_lock(flags) local_irq_save(flags)
#define bitops_unlock(flags) local_irq_restore(flags)
#endif /* !CONFIG_ARC_HAS_LLSC */
#endif