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-rw-r--r--arch/riscv/include/asm/atomic.h103
-rw-r--r--arch/riscv/include/asm/barrier.h23
-rw-r--r--arch/riscv/include/asm/bitops.h2
-rw-r--r--arch/riscv/include/asm/spinlock.h11
-rw-r--r--arch/riscv/include/asm/tlbflush.h5
5 files changed, 60 insertions, 84 deletions
diff --git a/arch/riscv/include/asm/atomic.h b/arch/riscv/include/asm/atomic.h
index e2e37c57cbeb..e65d1cd89e28 100644
--- a/arch/riscv/include/asm/atomic.h
+++ b/arch/riscv/include/asm/atomic.h
@@ -50,30 +50,30 @@ static __always_inline void atomic64_set(atomic64_t *v, long i)
* have the AQ or RL bits set. These don't return anything, so there's only
* one version to worry about.
*/
-#define ATOMIC_OP(op, asm_op, c_op, I, asm_type, c_type, prefix) \
-static __always_inline void atomic##prefix##_##op(c_type i, atomic##prefix##_t *v) \
-{ \
- __asm__ __volatile__ ( \
- "amo" #asm_op "." #asm_type " zero, %1, %0" \
- : "+A" (v->counter) \
- : "r" (I) \
- : "memory"); \
+#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) \
+{ \
+ __asm__ __volatile__ ( \
+ "amo" #asm_op "." #asm_type " zero, %1, %0" \
+ : "+A" (v->counter) \
+ : "r" (I) \
+ : "memory"); \
}
#ifdef CONFIG_GENERIC_ATOMIC64
-#define ATOMIC_OPS(op, asm_op, c_op, I) \
- ATOMIC_OP (op, asm_op, c_op, I, w, int, )
+#define ATOMIC_OPS(op, asm_op, I) \
+ ATOMIC_OP (op, asm_op, I, w, int, )
#else
-#define ATOMIC_OPS(op, asm_op, c_op, I) \
- ATOMIC_OP (op, asm_op, c_op, I, w, int, ) \
- ATOMIC_OP (op, asm_op, c_op, I, d, long, 64)
+#define ATOMIC_OPS(op, asm_op, I) \
+ ATOMIC_OP (op, asm_op, I, w, int, ) \
+ ATOMIC_OP (op, asm_op, I, d, long, 64)
#endif
-ATOMIC_OPS(add, add, +, i)
-ATOMIC_OPS(sub, add, +, -i)
-ATOMIC_OPS(and, and, &, i)
-ATOMIC_OPS( or, or, |, i)
-ATOMIC_OPS(xor, xor, ^, i)
+ATOMIC_OPS(add, add, i)
+ATOMIC_OPS(sub, add, -i)
+ATOMIC_OPS(and, and, i)
+ATOMIC_OPS( or, or, i)
+ATOMIC_OPS(xor, xor, i)
#undef ATOMIC_OP
#undef ATOMIC_OPS
@@ -83,7 +83,7 @@ ATOMIC_OPS(xor, xor, ^, i)
* There's two flavors of these: the arithmatic ops have both fetch and return
* versions, while the logical ops only have fetch versions.
*/
-#define ATOMIC_FETCH_OP(op, asm_op, c_op, I, asm_or, c_or, asm_type, c_type, prefix) \
+#define ATOMIC_FETCH_OP(op, asm_op, I, asm_or, c_or, asm_type, c_type, prefix) \
static __always_inline c_type atomic##prefix##_fetch_##op##c_or(c_type i, atomic##prefix##_t *v) \
{ \
register c_type ret; \
@@ -103,13 +103,13 @@ static __always_inline c_type atomic##prefix##_##op##_return##c_or(c_type i, ato
#ifdef CONFIG_GENERIC_ATOMIC64
#define ATOMIC_OPS(op, asm_op, c_op, I, asm_or, c_or) \
- ATOMIC_FETCH_OP (op, asm_op, c_op, I, asm_or, c_or, w, int, ) \
+ ATOMIC_FETCH_OP (op, asm_op, I, asm_or, c_or, w, int, ) \
ATOMIC_OP_RETURN(op, asm_op, c_op, I, asm_or, c_or, w, int, )
#else
#define ATOMIC_OPS(op, asm_op, c_op, I, asm_or, c_or) \
- ATOMIC_FETCH_OP (op, asm_op, c_op, I, asm_or, c_or, w, int, ) \
+ ATOMIC_FETCH_OP (op, asm_op, I, asm_or, c_or, w, int, ) \
ATOMIC_OP_RETURN(op, asm_op, c_op, I, asm_or, c_or, w, int, ) \
- ATOMIC_FETCH_OP (op, asm_op, c_op, I, asm_or, c_or, d, long, 64) \
+ ATOMIC_FETCH_OP (op, asm_op, I, asm_or, c_or, d, long, 64) \
ATOMIC_OP_RETURN(op, asm_op, c_op, I, asm_or, c_or, d, long, 64)
#endif
@@ -126,28 +126,28 @@ ATOMIC_OPS(sub, add, +, -i, .aqrl, )
#undef ATOMIC_OPS
#ifdef CONFIG_GENERIC_ATOMIC64
-#define ATOMIC_OPS(op, asm_op, c_op, I, asm_or, c_or) \
- ATOMIC_FETCH_OP(op, asm_op, c_op, I, asm_or, c_or, w, int, )
+#define ATOMIC_OPS(op, asm_op, I, asm_or, c_or) \
+ ATOMIC_FETCH_OP(op, asm_op, I, asm_or, c_or, w, int, )
#else
-#define ATOMIC_OPS(op, asm_op, c_op, I, asm_or, c_or) \
- ATOMIC_FETCH_OP(op, asm_op, c_op, I, asm_or, c_or, w, int, ) \
- ATOMIC_FETCH_OP(op, asm_op, c_op, I, asm_or, c_or, d, long, 64)
+#define ATOMIC_OPS(op, asm_op, I, asm_or, c_or) \
+ ATOMIC_FETCH_OP(op, asm_op, I, asm_or, c_or, w, int, ) \
+ ATOMIC_FETCH_OP(op, asm_op, I, asm_or, c_or, d, long, 64)
#endif
-ATOMIC_OPS(and, and, &, i, , _relaxed)
-ATOMIC_OPS(and, and, &, i, .aq , _acquire)
-ATOMIC_OPS(and, and, &, i, .rl , _release)
-ATOMIC_OPS(and, and, &, i, .aqrl, )
+ATOMIC_OPS(and, and, i, , _relaxed)
+ATOMIC_OPS(and, and, i, .aq , _acquire)
+ATOMIC_OPS(and, and, i, .rl , _release)
+ATOMIC_OPS(and, and, i, .aqrl, )
-ATOMIC_OPS( or, or, |, i, , _relaxed)
-ATOMIC_OPS( or, or, |, i, .aq , _acquire)
-ATOMIC_OPS( or, or, |, i, .rl , _release)
-ATOMIC_OPS( or, or, |, i, .aqrl, )
+ATOMIC_OPS( or, or, i, , _relaxed)
+ATOMIC_OPS( or, or, i, .aq , _acquire)
+ATOMIC_OPS( or, or, i, .rl , _release)
+ATOMIC_OPS( or, or, i, .aqrl, )
-ATOMIC_OPS(xor, xor, ^, i, , _relaxed)
-ATOMIC_OPS(xor, xor, ^, i, .aq , _acquire)
-ATOMIC_OPS(xor, xor, ^, i, .rl , _release)
-ATOMIC_OPS(xor, xor, ^, i, .aqrl, )
+ATOMIC_OPS(xor, xor, i, , _relaxed)
+ATOMIC_OPS(xor, xor, i, .aq , _acquire)
+ATOMIC_OPS(xor, xor, i, .rl , _release)
+ATOMIC_OPS(xor, xor, i, .aqrl, )
#undef ATOMIC_OPS
@@ -182,13 +182,13 @@ ATOMIC_OPS(add_negative, add, <, 0)
#undef ATOMIC_OP
#undef ATOMIC_OPS
-#define ATOMIC_OP(op, func_op, c_op, I, c_type, prefix) \
+#define ATOMIC_OP(op, func_op, I, c_type, prefix) \
static __always_inline void atomic##prefix##_##op(atomic##prefix##_t *v) \
{ \
atomic##prefix##_##func_op(I, v); \
}
-#define ATOMIC_FETCH_OP(op, func_op, c_op, I, c_type, prefix) \
+#define ATOMIC_FETCH_OP(op, func_op, I, c_type, prefix) \
static __always_inline c_type atomic##prefix##_fetch_##op(atomic##prefix##_t *v) \
{ \
return atomic##prefix##_fetch_##func_op(I, v); \
@@ -202,16 +202,16 @@ static __always_inline c_type atomic##prefix##_##op##_return(atomic##prefix##_t
#ifdef CONFIG_GENERIC_ATOMIC64
#define ATOMIC_OPS(op, asm_op, c_op, I) \
- ATOMIC_OP (op, asm_op, c_op, I, int, ) \
- ATOMIC_FETCH_OP (op, asm_op, c_op, I, int, ) \
+ ATOMIC_OP (op, asm_op, I, int, ) \
+ ATOMIC_FETCH_OP (op, asm_op, I, int, ) \
ATOMIC_OP_RETURN(op, asm_op, c_op, I, int, )
#else
#define ATOMIC_OPS(op, asm_op, c_op, I) \
- ATOMIC_OP (op, asm_op, c_op, I, int, ) \
- ATOMIC_FETCH_OP (op, asm_op, c_op, I, int, ) \
+ ATOMIC_OP (op, asm_op, I, int, ) \
+ ATOMIC_FETCH_OP (op, asm_op, I, int, ) \
ATOMIC_OP_RETURN(op, asm_op, c_op, I, int, ) \
- ATOMIC_OP (op, asm_op, c_op, I, long, 64) \
- ATOMIC_FETCH_OP (op, asm_op, c_op, I, long, 64) \
+ ATOMIC_OP (op, asm_op, I, long, 64) \
+ ATOMIC_FETCH_OP (op, asm_op, I, long, 64) \
ATOMIC_OP_RETURN(op, asm_op, c_op, I, long, 64)
#endif
@@ -300,8 +300,13 @@ static __always_inline long atomic64_inc_not_zero(atomic64_t *v)
/*
* atomic_{cmp,}xchg is required to have exactly the same ordering semantics as
- * {cmp,}xchg and the operations that return, so they need a barrier. We just
- * use the other implementations directly.
+ * {cmp,}xchg and the operations that return, so they need a barrier.
+ */
+/*
+ * FIXME: atomic_cmpxchg_{acquire,release,relaxed} are all implemented by
+ * assigning the same barrier to both the LR and SC operations, but that might
+ * not make any sense. We're waiting on a memory model specification to
+ * determine exactly what the right thing to do is here.
*/
#define ATOMIC_OP(c_t, prefix, c_or, size, asm_or) \
static __always_inline c_t atomic##prefix##_cmpxchg##c_or(atomic##prefix##_t *v, c_t o, c_t n) \
diff --git a/arch/riscv/include/asm/barrier.h b/arch/riscv/include/asm/barrier.h
index 183534b7c39b..773c4e039cd7 100644
--- a/arch/riscv/include/asm/barrier.h
+++ b/arch/riscv/include/asm/barrier.h
@@ -38,29 +38,6 @@
#define smp_rmb() RISCV_FENCE(r,r)
#define smp_wmb() RISCV_FENCE(w,w)
-/*
- * These fences exist to enforce ordering around the relaxed AMOs. The
- * documentation defines that
- * "
- * atomic_fetch_add();
- * is equivalent to:
- * smp_mb__before_atomic();
- * atomic_fetch_add_relaxed();
- * smp_mb__after_atomic();
- * "
- * So we emit full fences on both sides.
- */
-#define __smb_mb__before_atomic() smp_mb()
-#define __smb_mb__after_atomic() smp_mb()
-
-/*
- * These barriers prevent accesses performed outside a spinlock from being moved
- * inside a spinlock. Since RISC-V sets the aq/rl bits on our spinlock only
- * enforce release consistency, we need full fences here.
- */
-#define smb_mb__before_spinlock() smp_mb()
-#define smb_mb__after_spinlock() smp_mb()
-
#include <asm-generic/barrier.h>
#endif /* __ASSEMBLY__ */
diff --git a/arch/riscv/include/asm/bitops.h b/arch/riscv/include/asm/bitops.h
index 7c281ef1d583..f30daf26f08f 100644
--- a/arch/riscv/include/asm/bitops.h
+++ b/arch/riscv/include/asm/bitops.h
@@ -67,7 +67,7 @@
: "memory");
#define __test_and_op_bit(op, mod, nr, addr) \
- __test_and_op_bit_ord(op, mod, nr, addr, )
+ __test_and_op_bit_ord(op, mod, nr, addr, .aqrl)
#define __op_bit(op, mod, nr, addr) \
__op_bit_ord(op, mod, nr, addr, )
diff --git a/arch/riscv/include/asm/spinlock.h b/arch/riscv/include/asm/spinlock.h
index 04c71d938afd..2fd27e8ef1fd 100644
--- a/arch/riscv/include/asm/spinlock.h
+++ b/arch/riscv/include/asm/spinlock.h
@@ -24,7 +24,7 @@
/* FIXME: Replace this with a ticket lock, like MIPS. */
-#define arch_spin_is_locked(x) ((x)->lock != 0)
+#define arch_spin_is_locked(x) (READ_ONCE((x)->lock) != 0)
static inline void arch_spin_unlock(arch_spinlock_t *lock)
{
@@ -58,15 +58,6 @@ static inline void arch_spin_lock(arch_spinlock_t *lock)
}
}
-static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
-{
- smp_rmb();
- do {
- cpu_relax();
- } while (arch_spin_is_locked(lock));
- smp_acquire__after_ctrl_dep();
-}
-
/***********************************************************/
static inline void arch_read_lock(arch_rwlock_t *lock)
diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h
index 5ee4ae370b5e..c79fab3d377d 100644
--- a/arch/riscv/include/asm/tlbflush.h
+++ b/arch/riscv/include/asm/tlbflush.h
@@ -17,7 +17,10 @@
#ifdef CONFIG_MMU
-/* Flush entire local TLB */
+/*
+ * Flush entire local TLB. 'sfence.vma' implicitly fences with the instruction
+ * cache as well, so a 'fence.i' is not necessary.
+ */
static inline void local_flush_tlb_all(void)
{
__asm__ __volatile__ ("sfence.vma" : : : "memory");