[PATCH v2 28/33] locking/atomic: riscv: move to ARCH_ATOMIC

From: Mark Rutland
Date: Tue May 25 2021 - 10:07:43 EST


We'd like all architectures to convert to ARCH_ATOMIC, as once all
architectures are converted it will be possible to make significant
cleanups to the atomics headers, and this will make it much easier to
generically enable atomic functionality (e.g. debug logic in the
instrumented wrappers).

As a step towards that, this patch migrates riscv to ARCH_ATOMIC. The
arch code provides arch_{atomic,atomic64,xchg,cmpxchg}*(), and common
code wraps these with optional instrumentation to provide the regular
functions.

Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
Acked-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
Cc: Boqun Feng <boqun.feng@xxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
---
arch/riscv/Kconfig | 1 +
arch/riscv/include/asm/atomic.h | 128 +++++++++++++++++++--------------------
arch/riscv/include/asm/cmpxchg.h | 34 +++++------
3 files changed, 82 insertions(+), 81 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index a8ad8eb76120..c59b9f4a9d62 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -12,6 +12,7 @@ config 32BIT

config RISCV
def_bool y
+ select ARCH_ATOMIC
select ARCH_CLOCKSOURCE_INIT
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_DEBUG_PAGEALLOC if MMU
diff --git a/arch/riscv/include/asm/atomic.h b/arch/riscv/include/asm/atomic.h
index 400a8c8b6de7..ac9bdf4fc404 100644
--- a/arch/riscv/include/asm/atomic.h
+++ b/arch/riscv/include/asm/atomic.h
@@ -25,22 +25,22 @@
#define __atomic_release_fence() \
__asm__ __volatile__(RISCV_RELEASE_BARRIER "" ::: "memory");

-static __always_inline int atomic_read(const atomic_t *v)
+static __always_inline int arch_atomic_read(const atomic_t *v)
{
return READ_ONCE(v->counter);
}
-static __always_inline void atomic_set(atomic_t *v, int i)
+static __always_inline void arch_atomic_set(atomic_t *v, int i)
{
WRITE_ONCE(v->counter, i);
}

#ifndef CONFIG_GENERIC_ATOMIC64
#define ATOMIC64_INIT(i) { (i) }
-static __always_inline s64 atomic64_read(const atomic64_t *v)
+static __always_inline s64 arch_atomic64_read(const atomic64_t *v)
{
return READ_ONCE(v->counter);
}
-static __always_inline void atomic64_set(atomic64_t *v, s64 i)
+static __always_inline void arch_atomic64_set(atomic64_t *v, s64 i)
{
WRITE_ONCE(v->counter, i);
}
@@ -53,7 +53,7 @@ static __always_inline void atomic64_set(atomic64_t *v, s64 i)
*/
#define ATOMIC_OP(op, asm_op, I, asm_type, c_type, prefix) \
static __always_inline \
-void atomic##prefix##_##op(c_type i, atomic##prefix##_t *v) \
+void arch_atomic##prefix##_##op(c_type i, atomic##prefix##_t *v) \
{ \
__asm__ __volatile__ ( \
" amo" #asm_op "." #asm_type " zero, %1, %0" \
@@ -87,7 +87,7 @@ ATOMIC_OPS(xor, xor, i)
*/
#define ATOMIC_FETCH_OP(op, asm_op, I, asm_type, c_type, prefix) \
static __always_inline \
-c_type atomic##prefix##_fetch_##op##_relaxed(c_type i, \
+c_type arch_atomic##prefix##_fetch_##op##_relaxed(c_type i, \
atomic##prefix##_t *v) \
{ \
register c_type ret; \
@@ -99,7 +99,7 @@ c_type atomic##prefix##_fetch_##op##_relaxed(c_type i, \
return ret; \
} \
static __always_inline \
-c_type atomic##prefix##_fetch_##op(c_type i, atomic##prefix##_t *v) \
+c_type arch_atomic##prefix##_fetch_##op(c_type i, atomic##prefix##_t *v) \
{ \
register c_type ret; \
__asm__ __volatile__ ( \
@@ -112,15 +112,15 @@ c_type atomic##prefix##_fetch_##op(c_type i, atomic##prefix##_t *v) \

#define ATOMIC_OP_RETURN(op, asm_op, c_op, I, asm_type, c_type, prefix) \
static __always_inline \
-c_type atomic##prefix##_##op##_return_relaxed(c_type i, \
+c_type arch_atomic##prefix##_##op##_return_relaxed(c_type i, \
atomic##prefix##_t *v) \
{ \
- return atomic##prefix##_fetch_##op##_relaxed(i, v) c_op I; \
+ return arch_atomic##prefix##_fetch_##op##_relaxed(i, v) c_op I; \
} \
static __always_inline \
-c_type atomic##prefix##_##op##_return(c_type i, atomic##prefix##_t *v) \
+c_type arch_atomic##prefix##_##op##_return(c_type i, atomic##prefix##_t *v) \
{ \
- return atomic##prefix##_fetch_##op(i, v) c_op I; \
+ return arch_atomic##prefix##_fetch_##op(i, v) c_op I; \
}

#ifdef CONFIG_GENERIC_ATOMIC64
@@ -138,26 +138,26 @@ c_type atomic##prefix##_##op##_return(c_type i, atomic##prefix##_t *v) \
ATOMIC_OPS(add, add, +, i)
ATOMIC_OPS(sub, add, +, -i)

-#define atomic_add_return_relaxed atomic_add_return_relaxed
-#define atomic_sub_return_relaxed atomic_sub_return_relaxed
-#define atomic_add_return atomic_add_return
-#define atomic_sub_return atomic_sub_return
+#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_add_return arch_atomic_add_return
+#define arch_atomic_sub_return arch_atomic_sub_return

-#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed
-#define atomic_fetch_sub_relaxed atomic_fetch_sub_relaxed
-#define atomic_fetch_add atomic_fetch_add
-#define atomic_fetch_sub atomic_fetch_sub
+#define arch_atomic_fetch_add_relaxed arch_atomic_fetch_add_relaxed
+#define arch_atomic_fetch_sub_relaxed arch_atomic_fetch_sub_relaxed
+#define arch_atomic_fetch_add arch_atomic_fetch_add
+#define arch_atomic_fetch_sub arch_atomic_fetch_sub

#ifndef CONFIG_GENERIC_ATOMIC64
-#define atomic64_add_return_relaxed atomic64_add_return_relaxed
-#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed
-#define atomic64_add_return atomic64_add_return
-#define atomic64_sub_return atomic64_sub_return
-
-#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed
-#define atomic64_fetch_sub_relaxed atomic64_fetch_sub_relaxed
-#define atomic64_fetch_add atomic64_fetch_add
-#define atomic64_fetch_sub atomic64_fetch_sub
+#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_add_return arch_atomic64_add_return
+#define arch_atomic64_sub_return arch_atomic64_sub_return
+
+#define arch_atomic64_fetch_add_relaxed arch_atomic64_fetch_add_relaxed
+#define arch_atomic64_fetch_sub_relaxed arch_atomic64_fetch_sub_relaxed
+#define arch_atomic64_fetch_add arch_atomic64_fetch_add
+#define arch_atomic64_fetch_sub arch_atomic64_fetch_sub
#endif

#undef ATOMIC_OPS
@@ -175,20 +175,20 @@ ATOMIC_OPS(and, and, i)
ATOMIC_OPS( or, or, i)
ATOMIC_OPS(xor, xor, i)

-#define atomic_fetch_and_relaxed atomic_fetch_and_relaxed
-#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed
-#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed
-#define atomic_fetch_and atomic_fetch_and
-#define atomic_fetch_or atomic_fetch_or
-#define atomic_fetch_xor atomic_fetch_xor
+#define arch_atomic_fetch_and_relaxed arch_atomic_fetch_and_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_atomic_fetch_and arch_atomic_fetch_and
+#define arch_atomic_fetch_or arch_atomic_fetch_or
+#define arch_atomic_fetch_xor arch_atomic_fetch_xor

#ifndef CONFIG_GENERIC_ATOMIC64
-#define atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed
-#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed
-#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed
-#define atomic64_fetch_and atomic64_fetch_and
-#define atomic64_fetch_or atomic64_fetch_or
-#define atomic64_fetch_xor atomic64_fetch_xor
+#define arch_atomic64_fetch_and_relaxed arch_atomic64_fetch_and_relaxed
+#define arch_atomic64_fetch_or_relaxed arch_atomic64_fetch_or_relaxed
+#define arch_atomic64_fetch_xor_relaxed arch_atomic64_fetch_xor_relaxed
+#define arch_atomic64_fetch_and arch_atomic64_fetch_and
+#define arch_atomic64_fetch_or arch_atomic64_fetch_or
+#define arch_atomic64_fetch_xor arch_atomic64_fetch_xor
#endif

#undef ATOMIC_OPS
@@ -197,7 +197,7 @@ ATOMIC_OPS(xor, xor, i)
#undef ATOMIC_OP_RETURN

/* This is required to provide a full barrier on success. */
-static __always_inline int atomic_fetch_add_unless(atomic_t *v, int a, int u)
+static __always_inline int arch_atomic_fetch_add_unless(atomic_t *v, int a, int u)
{
int prev, rc;

@@ -214,10 +214,10 @@ static __always_inline int atomic_fetch_add_unless(atomic_t *v, int a, int u)
: "memory");
return prev;
}
-#define atomic_fetch_add_unless atomic_fetch_add_unless
+#define arch_atomic_fetch_add_unless arch_atomic_fetch_add_unless

#ifndef CONFIG_GENERIC_ATOMIC64
-static __always_inline s64 atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
+static __always_inline s64 arch_atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
{
s64 prev;
long rc;
@@ -235,7 +235,7 @@ static __always_inline s64 atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u
: "memory");
return prev;
}
-#define atomic64_fetch_add_unless atomic64_fetch_add_unless
+#define arch_atomic64_fetch_add_unless arch_atomic64_fetch_add_unless
#endif

/*
@@ -244,45 +244,45 @@ static __always_inline s64 atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u
*/
#define ATOMIC_OP(c_t, prefix, size) \
static __always_inline \
-c_t atomic##prefix##_xchg_relaxed(atomic##prefix##_t *v, c_t n) \
+c_t arch_atomic##prefix##_xchg_relaxed(atomic##prefix##_t *v, c_t n) \
{ \
return __xchg_relaxed(&(v->counter), n, size); \
} \
static __always_inline \
-c_t atomic##prefix##_xchg_acquire(atomic##prefix##_t *v, c_t n) \
+c_t arch_atomic##prefix##_xchg_acquire(atomic##prefix##_t *v, c_t n) \
{ \
return __xchg_acquire(&(v->counter), n, size); \
} \
static __always_inline \
-c_t atomic##prefix##_xchg_release(atomic##prefix##_t *v, c_t n) \
+c_t arch_atomic##prefix##_xchg_release(atomic##prefix##_t *v, c_t n) \
{ \
return __xchg_release(&(v->counter), n, size); \
} \
static __always_inline \
-c_t atomic##prefix##_xchg(atomic##prefix##_t *v, c_t n) \
+c_t arch_atomic##prefix##_xchg(atomic##prefix##_t *v, c_t n) \
{ \
return __xchg(&(v->counter), n, size); \
} \
static __always_inline \
-c_t atomic##prefix##_cmpxchg_relaxed(atomic##prefix##_t *v, \
+c_t arch_atomic##prefix##_cmpxchg_relaxed(atomic##prefix##_t *v, \
c_t o, c_t n) \
{ \
return __cmpxchg_relaxed(&(v->counter), o, n, size); \
} \
static __always_inline \
-c_t atomic##prefix##_cmpxchg_acquire(atomic##prefix##_t *v, \
+c_t arch_atomic##prefix##_cmpxchg_acquire(atomic##prefix##_t *v, \
c_t o, c_t n) \
{ \
return __cmpxchg_acquire(&(v->counter), o, n, size); \
} \
static __always_inline \
-c_t atomic##prefix##_cmpxchg_release(atomic##prefix##_t *v, \
+c_t arch_atomic##prefix##_cmpxchg_release(atomic##prefix##_t *v, \
c_t o, c_t n) \
{ \
return __cmpxchg_release(&(v->counter), o, n, size); \
} \
static __always_inline \
-c_t atomic##prefix##_cmpxchg(atomic##prefix##_t *v, c_t o, c_t n) \
+c_t arch_atomic##prefix##_cmpxchg(atomic##prefix##_t *v, c_t o, c_t n) \
{ \
return __cmpxchg(&(v->counter), o, n, size); \
}
@@ -298,19 +298,19 @@ c_t atomic##prefix##_cmpxchg(atomic##prefix##_t *v, c_t o, c_t n) \

ATOMIC_OPS()

-#define atomic_xchg_relaxed atomic_xchg_relaxed
-#define atomic_xchg_acquire atomic_xchg_acquire
-#define atomic_xchg_release atomic_xchg_release
-#define atomic_xchg atomic_xchg
-#define atomic_cmpxchg_relaxed atomic_cmpxchg_relaxed
-#define atomic_cmpxchg_acquire atomic_cmpxchg_acquire
-#define atomic_cmpxchg_release atomic_cmpxchg_release
-#define atomic_cmpxchg atomic_cmpxchg
+#define arch_atomic_xchg_relaxed arch_atomic_xchg_relaxed
+#define arch_atomic_xchg_acquire arch_atomic_xchg_acquire
+#define arch_atomic_xchg_release arch_atomic_xchg_release
+#define arch_atomic_xchg arch_atomic_xchg
+#define arch_atomic_cmpxchg_relaxed arch_atomic_cmpxchg_relaxed
+#define arch_atomic_cmpxchg_acquire arch_atomic_cmpxchg_acquire
+#define arch_atomic_cmpxchg_release arch_atomic_cmpxchg_release
+#define arch_atomic_cmpxchg arch_atomic_cmpxchg

#undef ATOMIC_OPS
#undef ATOMIC_OP

-static __always_inline int atomic_sub_if_positive(atomic_t *v, int offset)
+static __always_inline int arch_atomic_sub_if_positive(atomic_t *v, int offset)
{
int prev, rc;

@@ -328,10 +328,10 @@ static __always_inline int atomic_sub_if_positive(atomic_t *v, int offset)
return prev - offset;
}

-#define atomic_dec_if_positive(v) atomic_sub_if_positive(v, 1)
+#define arch_atomic_dec_if_positive(v) arch_atomic_sub_if_positive(v, 1)

#ifndef CONFIG_GENERIC_ATOMIC64
-static __always_inline s64 atomic64_sub_if_positive(atomic64_t *v, s64 offset)
+static __always_inline s64 arch_atomic64_sub_if_positive(atomic64_t *v, s64 offset)
{
s64 prev;
long rc;
@@ -350,7 +350,7 @@ static __always_inline s64 atomic64_sub_if_positive(atomic64_t *v, s64 offset)
return prev - offset;
}

-#define atomic64_dec_if_positive(v) atomic64_sub_if_positive(v, 1)
+#define arch_atomic64_dec_if_positive(v) arch_atomic64_sub_if_positive(v, 1)
#endif

#endif /* _ASM_RISCV_ATOMIC_H */
diff --git a/arch/riscv/include/asm/cmpxchg.h b/arch/riscv/include/asm/cmpxchg.h
index 262e5bbb2776..36dc962f6343 100644
--- a/arch/riscv/include/asm/cmpxchg.h
+++ b/arch/riscv/include/asm/cmpxchg.h
@@ -37,7 +37,7 @@
__ret; \
})

-#define xchg_relaxed(ptr, x) \
+#define arch_xchg_relaxed(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg_relaxed((ptr), \
@@ -72,7 +72,7 @@
__ret; \
})

-#define xchg_acquire(ptr, x) \
+#define arch_xchg_acquire(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg_acquire((ptr), \
@@ -107,7 +107,7 @@
__ret; \
})

-#define xchg_release(ptr, x) \
+#define arch_xchg_release(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg_release((ptr), \
@@ -140,7 +140,7 @@
__ret; \
})

-#define xchg(ptr, x) \
+#define arch_xchg(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg((ptr), _x_, sizeof(*(ptr))); \
@@ -149,13 +149,13 @@
#define xchg32(ptr, x) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 4); \
- xchg((ptr), (x)); \
+ arch_xchg((ptr), (x)); \
})

#define xchg64(ptr, x) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
- xchg((ptr), (x)); \
+ arch_xchg((ptr), (x)); \
})

/*
@@ -199,7 +199,7 @@
__ret; \
})

-#define cmpxchg_relaxed(ptr, o, n) \
+#define arch_cmpxchg_relaxed(ptr, o, n) \
({ \
__typeof__(*(ptr)) _o_ = (o); \
__typeof__(*(ptr)) _n_ = (n); \
@@ -245,7 +245,7 @@
__ret; \
})

-#define cmpxchg_acquire(ptr, o, n) \
+#define arch_cmpxchg_acquire(ptr, o, n) \
({ \
__typeof__(*(ptr)) _o_ = (o); \
__typeof__(*(ptr)) _n_ = (n); \
@@ -291,7 +291,7 @@
__ret; \
})

-#define cmpxchg_release(ptr, o, n) \
+#define arch_cmpxchg_release(ptr, o, n) \
({ \
__typeof__(*(ptr)) _o_ = (o); \
__typeof__(*(ptr)) _n_ = (n); \
@@ -337,7 +337,7 @@
__ret; \
})

-#define cmpxchg(ptr, o, n) \
+#define arch_cmpxchg(ptr, o, n) \
({ \
__typeof__(*(ptr)) _o_ = (o); \
__typeof__(*(ptr)) _n_ = (n); \
@@ -345,31 +345,31 @@
_o_, _n_, sizeof(*(ptr))); \
})

-#define cmpxchg_local(ptr, o, n) \
+#define arch_cmpxchg_local(ptr, o, n) \
(__cmpxchg_relaxed((ptr), (o), (n), sizeof(*(ptr))))

#define cmpxchg32(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 4); \
- cmpxchg((ptr), (o), (n)); \
+ arch_cmpxchg((ptr), (o), (n)); \
})

#define cmpxchg32_local(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 4); \
- cmpxchg_relaxed((ptr), (o), (n)) \
+ arch_cmpxchg_relaxed((ptr), (o), (n)) \
})

-#define cmpxchg64(ptr, o, n) \
+#define arch_cmpxchg64(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
- cmpxchg((ptr), (o), (n)); \
+ arch_cmpxchg((ptr), (o), (n)); \
})

-#define cmpxchg64_local(ptr, o, n) \
+#define arch_cmpxchg64_local(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
- cmpxchg_relaxed((ptr), (o), (n)); \
+ arch_cmpxchg_relaxed((ptr), (o), (n)); \
})

#endif /* _ASM_RISCV_CMPXCHG_H */
--
2.11.0