Some of the atomics return the result of a test applied after the atomic
operation, and almost all architectures implement these as trivial
wrappers around the underlying atomic. Specifically:
* <atomic>_inc_and_test(v) is (<atomic>_inc_return(v) == 0)
* <atomic>_dec_and_test(v) is (<atomic>_dec_return(v) == 0)
* <atomic>_sub_and_test(i, v) is (<atomic>_sub_return(i, v) == 0)
* <atomic>_add_negative(i, v) is (<atomic>_add_return(i, v) < 0)
Rather than have these definitions duplicated in all architectures, with
minor inconsistencies in formatting and documentation, let's make these
operations optional, with default fallbacks as above. Implementations
must now provide a preprocessor symbol.
The instrumented atomics are updated accordingly.
Both x86 and m68k have custom implementations, which are left as-is,
given preprocessor symbols to avoid being overridden.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutl...@arm.com>
Acked-by: Geert Uytterhoeven <ge...@linux-m68k.org>
Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org>
Cc: Boqun Feng <boqun.f...@gmail.com>
Cc: Will Deacon <will.dea...@arm.com>
---
arch/alpha/include/asm/atomic.h | 12 ---
arch/arc/include/asm/atomic.h | 10 ---
arch/arm/include/asm/atomic.h | 9 ---
arch/arm64/include/asm/atomic.h | 8 --
arch/h8300/include/asm/atomic.h | 5 --
arch/hexagon/include/asm/atomic.h | 5 --
arch/ia64/include/asm/atomic.h | 23 ------
arch/m68k/include/asm/atomic.h | 4 +
arch/mips/include/asm/atomic.h | 84 --------------------
arch/parisc/include/asm/atomic.h | 22 ------
arch/powerpc/include/asm/atomic.h | 30 --------
arch/riscv/include/asm/atomic.h | 46 -----------
arch/s390/include/asm/atomic.h | 8 --
arch/sh/include/asm/atomic.h | 4 -
arch/sparc/include/asm/atomic_32.h | 15 ----
arch/sparc/include/asm/atomic_64.h | 20 -----
arch/x86/include/asm/atomic.h | 4 +
arch/x86/include/asm/atomic64_32.h | 54 -------------
arch/x86/include/asm/atomic64_64.h | 4 +
arch/xtensa/include/asm/atomic.h | 42 ----------
include/asm-generic/atomic-instrumented.h | 24 ++++++
include/asm-generic/atomic.h | 9 ---
include/asm-generic/atomic64.h | 4 -
include/linux/atomic.h | 124 ++++++++++++++++++++++++++++++
24 files changed, 160 insertions(+), 410 deletions(-)
[...]
diff --git a/arch/riscv/include/asm/atomic.h b/arch/riscv/include/asm/atomic.h
index d959bbaaad41..68eef0a805ca 100644
--- a/arch/riscv/include/asm/atomic.h
+++ b/arch/riscv/include/asm/atomic.h
@@ -209,36 +209,6 @@ ATOMIC_OPS(xor, xor, i)
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
-/*
- * The extra atomic operations that are constructed from one of the core
- * AMO-based operations above (aside from sub, which is easier to fit above).
- * These are required to perform a full barrier, but they're OK this way
- * because atomic_*_return is also required to perform a full barrier.
- *
- */
-#define ATOMIC_OP(op, func_op, comp_op, I, c_type, prefix) \
-static __always_inline \
-bool atomic##prefix##_##op(c_type i, atomic##prefix##_t *v) \
-{ \
- return atomic##prefix##_##func_op##_return(i, v) comp_op I; \
-}
-
-#ifdef CONFIG_GENERIC_ATOMIC64
-#define ATOMIC_OPS(op, func_op, comp_op, I) \
- ATOMIC_OP(op, func_op, comp_op, I, int, )
-#else
-#define ATOMIC_OPS(op, func_op, comp_op, I) \
- ATOMIC_OP(op, func_op, comp_op, I, int, ) \
- ATOMIC_OP(op, func_op, comp_op, I, long, 64)
-#endif
-
-ATOMIC_OPS(add_and_test, add, ==, 0)
-ATOMIC_OPS(sub_and_test, sub, ==, 0)
-ATOMIC_OPS(add_negative, add, <, 0)
-
-#undef ATOMIC_OP
-#undef ATOMIC_OPS
-
#define ATOMIC_OP(op, func_op, I, c_type, prefix) \
static __always_inline \
void atomic##prefix##_##op(atomic##prefix##_t *v) \
@@ -315,22 +285,6 @@ ATOMIC_OPS(dec, add, +, -1)
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
-#define ATOMIC_OP(op, func_op, comp_op, I, prefix) \
-static __always_inline \
-bool atomic##prefix##_##op(atomic##prefix##_t *v) \
-{ \
- return atomic##prefix##_##func_op##_return(v) comp_op I; \
-}
-
-ATOMIC_OP(inc_and_test, inc, ==, 0, )
-ATOMIC_OP(dec_and_test, dec, ==, 0, )
-#ifndef CONFIG_GENERIC_ATOMIC64
-ATOMIC_OP(inc_and_test, inc, ==, 0, 64)
-ATOMIC_OP(dec_and_test, dec, ==, 0, 64)
-#endif
-
-#undef ATOMIC_OP
-
/* 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)
{
