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Diffstat (limited to 'arch/riscv/include/asm/atomic.h')
-rw-r--r--arch/riscv/include/asm/atomic.h102
1 files changed, 92 insertions, 10 deletions
diff --git a/arch/riscv/include/asm/atomic.h b/arch/riscv/include/asm/atomic.h
index ac9bdf4fc404..0dfe9d857a76 100644
--- a/arch/riscv/include/asm/atomic.h
+++ b/arch/riscv/include/asm/atomic.h
@@ -310,47 +310,129 @@ ATOMIC_OPS()
#undef ATOMIC_OPS
#undef ATOMIC_OP
-static __always_inline int arch_atomic_sub_if_positive(atomic_t *v, int offset)
+static __always_inline bool arch_atomic_inc_unless_negative(atomic_t *v)
+{
+ int prev, rc;
+
+ __asm__ __volatile__ (
+ "0: lr.w %[p], %[c]\n"
+ " bltz %[p], 1f\n"
+ " addi %[rc], %[p], 1\n"
+ " sc.w.rl %[rc], %[rc], %[c]\n"
+ " bnez %[rc], 0b\n"
+ " fence rw, rw\n"
+ "1:\n"
+ : [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
+ :
+ : "memory");
+ return !(prev < 0);
+}
+
+#define arch_atomic_inc_unless_negative arch_atomic_inc_unless_negative
+
+static __always_inline bool arch_atomic_dec_unless_positive(atomic_t *v)
+{
+ int prev, rc;
+
+ __asm__ __volatile__ (
+ "0: lr.w %[p], %[c]\n"
+ " bgtz %[p], 1f\n"
+ " addi %[rc], %[p], -1\n"
+ " sc.w.rl %[rc], %[rc], %[c]\n"
+ " bnez %[rc], 0b\n"
+ " fence rw, rw\n"
+ "1:\n"
+ : [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
+ :
+ : "memory");
+ return !(prev > 0);
+}
+
+#define arch_atomic_dec_unless_positive arch_atomic_dec_unless_positive
+
+static __always_inline int arch_atomic_dec_if_positive(atomic_t *v)
{
int prev, rc;
__asm__ __volatile__ (
"0: lr.w %[p], %[c]\n"
- " sub %[rc], %[p], %[o]\n"
+ " addi %[rc], %[p], -1\n"
" bltz %[rc], 1f\n"
" sc.w.rl %[rc], %[rc], %[c]\n"
" bnez %[rc], 0b\n"
" fence rw, rw\n"
"1:\n"
: [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
- : [o]"r" (offset)
+ :
: "memory");
- return prev - offset;
+ return prev - 1;
}
-#define arch_atomic_dec_if_positive(v) arch_atomic_sub_if_positive(v, 1)
+#define arch_atomic_dec_if_positive arch_atomic_dec_if_positive
#ifndef CONFIG_GENERIC_ATOMIC64
-static __always_inline s64 arch_atomic64_sub_if_positive(atomic64_t *v, s64 offset)
+static __always_inline bool arch_atomic64_inc_unless_negative(atomic64_t *v)
+{
+ s64 prev;
+ long rc;
+
+ __asm__ __volatile__ (
+ "0: lr.d %[p], %[c]\n"
+ " bltz %[p], 1f\n"
+ " addi %[rc], %[p], 1\n"
+ " sc.d.rl %[rc], %[rc], %[c]\n"
+ " bnez %[rc], 0b\n"
+ " fence rw, rw\n"
+ "1:\n"
+ : [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
+ :
+ : "memory");
+ return !(prev < 0);
+}
+
+#define arch_atomic64_inc_unless_negative arch_atomic64_inc_unless_negative
+
+static __always_inline bool arch_atomic64_dec_unless_positive(atomic64_t *v)
+{
+ s64 prev;
+ long rc;
+
+ __asm__ __volatile__ (
+ "0: lr.d %[p], %[c]\n"
+ " bgtz %[p], 1f\n"
+ " addi %[rc], %[p], -1\n"
+ " sc.d.rl %[rc], %[rc], %[c]\n"
+ " bnez %[rc], 0b\n"
+ " fence rw, rw\n"
+ "1:\n"
+ : [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
+ :
+ : "memory");
+ return !(prev > 0);
+}
+
+#define arch_atomic64_dec_unless_positive arch_atomic64_dec_unless_positive
+
+static __always_inline s64 arch_atomic64_dec_if_positive(atomic64_t *v)
{
s64 prev;
long rc;
__asm__ __volatile__ (
"0: lr.d %[p], %[c]\n"
- " sub %[rc], %[p], %[o]\n"
+ " addi %[rc], %[p], -1\n"
" bltz %[rc], 1f\n"
" sc.d.rl %[rc], %[rc], %[c]\n"
" bnez %[rc], 0b\n"
" fence rw, rw\n"
"1:\n"
: [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
- : [o]"r" (offset)
+ :
: "memory");
- return prev - offset;
+ return prev - 1;
}
-#define arch_atomic64_dec_if_positive(v) arch_atomic64_sub_if_positive(v, 1)
+#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
#endif
#endif /* _ASM_RISCV_ATOMIC_H */