From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- arch/alpha/include/asm/atomic.h | 306 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 306 insertions(+) create mode 100644 arch/alpha/include/asm/atomic.h (limited to 'arch/alpha/include/asm/atomic.h') diff --git a/arch/alpha/include/asm/atomic.h b/arch/alpha/include/asm/atomic.h new file mode 100644 index 000000000..f2861a43a --- /dev/null +++ b/arch/alpha/include/asm/atomic.h @@ -0,0 +1,306 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ALPHA_ATOMIC_H +#define _ALPHA_ATOMIC_H + +#include +#include +#include + +/* + * Atomic operations that C can't guarantee us. Useful for + * resource counting etc... + * + * But use these as seldom as possible since they are much slower + * than regular operations. + */ + +/* + * To ensure dependency ordering is preserved for the _relaxed and + * _release atomics, an smp_mb() is unconditionally inserted into the + * _relaxed variants, which are used to build the barriered versions. + * Avoid redundant back-to-back fences in the _acquire and _fence + * versions. + */ +#define __atomic_acquire_fence() +#define __atomic_post_full_fence() + +#define ATOMIC64_INIT(i) { (i) } + +#define arch_atomic_read(v) READ_ONCE((v)->counter) +#define arch_atomic64_read(v) READ_ONCE((v)->counter) + +#define arch_atomic_set(v,i) WRITE_ONCE((v)->counter, (i)) +#define arch_atomic64_set(v,i) WRITE_ONCE((v)->counter, (i)) + +/* + * 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. + */ + +#define ATOMIC_OP(op, asm_op) \ +static __inline__ void arch_atomic_##op(int i, atomic_t * v) \ +{ \ + unsigned long temp; \ + __asm__ __volatile__( \ + "1: ldl_l %0,%1\n" \ + " " #asm_op " %0,%2,%0\n" \ + " stl_c %0,%1\n" \ + " beq %0,2f\n" \ + ".subsection 2\n" \ + "2: br 1b\n" \ + ".previous" \ + :"=&r" (temp), "=m" (v->counter) \ + :"Ir" (i), "m" (v->counter)); \ +} \ + +#define ATOMIC_OP_RETURN(op, asm_op) \ +static inline int arch_atomic_##op##_return_relaxed(int i, atomic_t *v) \ +{ \ + long temp, result; \ + __asm__ __volatile__( \ + "1: ldl_l %0,%1\n" \ + " " #asm_op " %0,%3,%2\n" \ + " " #asm_op " %0,%3,%0\n" \ + " stl_c %0,%1\n" \ + " beq %0,2f\n" \ + ".subsection 2\n" \ + "2: br 1b\n" \ + ".previous" \ + :"=&r" (temp), "=m" (v->counter), "=&r" (result) \ + :"Ir" (i), "m" (v->counter) : "memory"); \ + smp_mb(); \ + return result; \ +} + +#define ATOMIC_FETCH_OP(op, asm_op) \ +static inline int arch_atomic_fetch_##op##_relaxed(int i, atomic_t *v) \ +{ \ + long temp, result; \ + __asm__ __volatile__( \ + "1: ldl_l %2,%1\n" \ + " " #asm_op " %2,%3,%0\n" \ + " stl_c %0,%1\n" \ + " beq %0,2f\n" \ + ".subsection 2\n" \ + "2: br 1b\n" \ + ".previous" \ + :"=&r" (temp), "=m" (v->counter), "=&r" (result) \ + :"Ir" (i), "m" (v->counter) : "memory"); \ + smp_mb(); \ + return result; \ +} + +#define ATOMIC64_OP(op, asm_op) \ +static __inline__ void arch_atomic64_##op(s64 i, atomic64_t * v) \ +{ \ + s64 temp; \ + __asm__ __volatile__( \ + "1: ldq_l %0,%1\n" \ + " " #asm_op " %0,%2,%0\n" \ + " stq_c %0,%1\n" \ + " beq %0,2f\n" \ + ".subsection 2\n" \ + "2: br 1b\n" \ + ".previous" \ + :"=&r" (temp), "=m" (v->counter) \ + :"Ir" (i), "m" (v->counter)); \ +} \ + +#define ATOMIC64_OP_RETURN(op, asm_op) \ +static __inline__ s64 \ +arch_atomic64_##op##_return_relaxed(s64 i, atomic64_t * v) \ +{ \ + s64 temp, result; \ + __asm__ __volatile__( \ + "1: ldq_l %0,%1\n" \ + " " #asm_op " %0,%3,%2\n" \ + " " #asm_op " %0,%3,%0\n" \ + " stq_c %0,%1\n" \ + " beq %0,2f\n" \ + ".subsection 2\n" \ + "2: br 1b\n" \ + ".previous" \ + :"=&r" (temp), "=m" (v->counter), "=&r" (result) \ + :"Ir" (i), "m" (v->counter) : "memory"); \ + smp_mb(); \ + return result; \ +} + +#define ATOMIC64_FETCH_OP(op, asm_op) \ +static __inline__ s64 \ +arch_atomic64_fetch_##op##_relaxed(s64 i, atomic64_t * v) \ +{ \ + s64 temp, result; \ + __asm__ __volatile__( \ + "1: ldq_l %2,%1\n" \ + " " #asm_op " %2,%3,%0\n" \ + " stq_c %0,%1\n" \ + " beq %0,2f\n" \ + ".subsection 2\n" \ + "2: br 1b\n" \ + ".previous" \ + :"=&r" (temp), "=m" (v->counter), "=&r" (result) \ + :"Ir" (i), "m" (v->counter) : "memory"); \ + smp_mb(); \ + return result; \ +} + +#define ATOMIC_OPS(op) \ + ATOMIC_OP(op, op##l) \ + ATOMIC_OP_RETURN(op, op##l) \ + ATOMIC_FETCH_OP(op, op##l) \ + ATOMIC64_OP(op, op##q) \ + ATOMIC64_OP_RETURN(op, op##q) \ + ATOMIC64_FETCH_OP(op, op##q) + +ATOMIC_OPS(add) +ATOMIC_OPS(sub) + +#define arch_atomic_add_return_relaxed arch_atomic_add_return_relaxed +#define arch_atomic_sub_return_relaxed arch_atomic_sub_return_relaxed +#define arch_atomic_fetch_add_relaxed arch_atomic_fetch_add_relaxed +#define arch_atomic_fetch_sub_relaxed arch_atomic_fetch_sub_relaxed + +#define arch_atomic64_add_return_relaxed arch_atomic64_add_return_relaxed +#define arch_atomic64_sub_return_relaxed arch_atomic64_sub_return_relaxed +#define arch_atomic64_fetch_add_relaxed arch_atomic64_fetch_add_relaxed +#define arch_atomic64_fetch_sub_relaxed arch_atomic64_fetch_sub_relaxed + +#define arch_atomic_andnot arch_atomic_andnot +#define arch_atomic64_andnot arch_atomic64_andnot + +#undef ATOMIC_OPS +#define ATOMIC_OPS(op, asm) \ + ATOMIC_OP(op, asm) \ + ATOMIC_FETCH_OP(op, asm) \ + ATOMIC64_OP(op, asm) \ + ATOMIC64_FETCH_OP(op, asm) + +ATOMIC_OPS(and, and) +ATOMIC_OPS(andnot, bic) +ATOMIC_OPS(or, bis) +ATOMIC_OPS(xor, xor) + +#define arch_atomic_fetch_and_relaxed arch_atomic_fetch_and_relaxed +#define arch_atomic_fetch_andnot_relaxed arch_atomic_fetch_andnot_relaxed +#define arch_atomic_fetch_or_relaxed arch_atomic_fetch_or_relaxed +#define arch_atomic_fetch_xor_relaxed arch_atomic_fetch_xor_relaxed + +#define arch_atomic64_fetch_and_relaxed arch_atomic64_fetch_and_relaxed +#define arch_atomic64_fetch_andnot_relaxed arch_atomic64_fetch_andnot_relaxed +#define arch_atomic64_fetch_or_relaxed arch_atomic64_fetch_or_relaxed +#define arch_atomic64_fetch_xor_relaxed arch_atomic64_fetch_xor_relaxed + +#undef ATOMIC_OPS +#undef ATOMIC64_FETCH_OP +#undef ATOMIC64_OP_RETURN +#undef ATOMIC64_OP +#undef ATOMIC_FETCH_OP +#undef ATOMIC_OP_RETURN +#undef ATOMIC_OP + +#define arch_atomic64_cmpxchg(v, old, new) \ + (arch_cmpxchg(&((v)->counter), old, new)) +#define arch_atomic64_xchg(v, new) \ + (arch_xchg(&((v)->counter), new)) + +#define arch_atomic_cmpxchg(v, old, new) \ + (arch_cmpxchg(&((v)->counter), old, new)) +#define arch_atomic_xchg(v, new) \ + (arch_xchg(&((v)->counter), new)) + +/** + * arch_atomic_fetch_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. + */ +static __inline__ int arch_atomic_fetch_add_unless(atomic_t *v, int a, int u) +{ + int c, new, old; + smp_mb(); + __asm__ __volatile__( + "1: ldl_l %[old],%[mem]\n" + " cmpeq %[old],%[u],%[c]\n" + " addl %[old],%[a],%[new]\n" + " bne %[c],2f\n" + " stl_c %[new],%[mem]\n" + " beq %[new],3f\n" + "2:\n" + ".subsection 2\n" + "3: br 1b\n" + ".previous" + : [old] "=&r"(old), [new] "=&r"(new), [c] "=&r"(c) + : [mem] "m"(*v), [a] "rI"(a), [u] "rI"((long)u) + : "memory"); + smp_mb(); + return old; +} +#define arch_atomic_fetch_add_unless arch_atomic_fetch_add_unless + +/** + * arch_atomic64_fetch_add_unless - add unless the number is a given value + * @v: pointer of type atomic64_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. + */ +static __inline__ s64 arch_atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u) +{ + s64 c, new, old; + smp_mb(); + __asm__ __volatile__( + "1: ldq_l %[old],%[mem]\n" + " cmpeq %[old],%[u],%[c]\n" + " addq %[old],%[a],%[new]\n" + " bne %[c],2f\n" + " stq_c %[new],%[mem]\n" + " beq %[new],3f\n" + "2:\n" + ".subsection 2\n" + "3: br 1b\n" + ".previous" + : [old] "=&r"(old), [new] "=&r"(new), [c] "=&r"(c) + : [mem] "m"(*v), [a] "rI"(a), [u] "rI"(u) + : "memory"); + smp_mb(); + return old; +} +#define arch_atomic64_fetch_add_unless arch_atomic64_fetch_add_unless + +/* + * arch_atomic64_dec_if_positive - decrement by 1 if old value positive + * @v: pointer of type atomic_t + * + * The function returns the old value of *v minus 1, even if + * the atomic variable, v, was not decremented. + */ +static inline s64 arch_atomic64_dec_if_positive(atomic64_t *v) +{ + s64 old, tmp; + smp_mb(); + __asm__ __volatile__( + "1: ldq_l %[old],%[mem]\n" + " subq %[old],1,%[tmp]\n" + " ble %[old],2f\n" + " stq_c %[tmp],%[mem]\n" + " beq %[tmp],3f\n" + "2:\n" + ".subsection 2\n" + "3: br 1b\n" + ".previous" + : [old] "=&r"(old), [tmp] "=&r"(tmp) + : [mem] "m"(*v) + : "memory"); + smp_mb(); + return old - 1; +} +#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive + +#endif /* _ALPHA_ATOMIC_H */ -- cgit v1.2.3