On Sat, May 1, 2021 at 12:04 AM Mark Rutland [off-list ref] wrote:

Hi Guo,

I had a look at completing the treewide conversion to ARCH_ATOMIC, and
I've pushed the results to my atomics/arch-atomic branch on kernel.org:

  https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/log/?h=atomics/arch-atomic
  git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git atomics/arch-atomic

Once v5.13-rc1 is out I intend to rebase and post the series to LKML.
The Kbuild test robot has been attacked the series for the last few
days, and I think it's fairly robust now, but if you wanted to take an
early look at the riscv or csky bits that'd be much appreciated.

riscv is ok, but csky:

  UPD     include/generated/timeconst.h
In file included from ./include/asm-generic/atomic.h:12:0,
                 from ./arch/csky/include/generated/asm/atomic.h:1,
                 from ./include/linux/atomic.h:7,
                 from ./include/asm-generic/bitops/lock.h:5,
                 from ./arch/csky/include/asm/bitops.h:70,
                 from ./include/linux/bitops.h:32,
                 from ./include/linux/kernel.h:11,
                 from ./include/asm-generic/bug.h:20,
                 from ./arch/csky/include/asm/bug.h:18,
                 from ./include/linux/bug.h:5,
                 from ./include/linux/page-flags.h:10,
                 from kernel/bounds.c:10:
./include/asm-generic/atomic.h: In function ‘generic_atomic_add_return’:
./arch/csky/include/asm/cmpxchg.h:71:10: error: implicit declaration
of function ‘cmpxchg_relaxed’ [-Werror=implicit-function-declaration]
  __ret = cmpxchg_relaxed(ptr, o, n);   \
          ^
./include/asm-generic/atomic.h:35:16: note: in expansion of macro ‘arch_cmpxchg’
  while ((old = arch_cmpxchg(&v->counter, c, c c_op i)) != c) \
                ^~~~~~~~~~~~
./include/asm-generic/atomic.h:96:1: note: in expansion of macro
‘ATOMIC_OP_RETURN’
 ATOMIC_OP_RETURN(add, +)
 ^~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
scripts/Makefile.build:116: recipe for target 'kernel/bounds.s' failed
make[1]: *** [kernel/bounds.s] Error 1
Makefile:1234: recipe for target 'prepare0' failed
make: *** [prepare0] Error 2

you can fixup with:

diff --git a/arch/csky/include/asm/cmpxchg.h b/arch/csky/include/asm/cmpxchg.h
index 9097854b8bed..af2f0660d351 100644
--- a/arch/csky/include/asm/cmpxchg.h
+++ b/arch/csky/include/asm/cmpxchg.h

@@ -64,15 +64,6 @@ extern void __bad_xchg(void);
 #define arch_cmpxchg_relaxed(ptr, o, n) \
        (__cmpxchg_relaxed((ptr), (o), (n), sizeof(*(ptr))))

-#define arch_cmpxchg(ptr, o, n)                                \
-({                                                             \
-       __typeof__(*(ptr)) __ret;                               \
-       __smp_release_fence();                                  \
-       __ret = cmpxchg_relaxed(ptr, o, n);                     \
-       __smp_acquire_fence();                                  \
-       __ret;                                                  \
-})
-
 #else
 #include <asm-generic/cmpxchg.h>
 #endif

diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
index 04b8be9f1a77..a6bc15b551ea 100644
--- a/include/asm-generic/atomic.h
+++ b/include/asm-generic/atomic.h

@@ -14,6 +14,17 @@

 #ifdef CONFIG_SMP

+#ifndef arch_cmpxchg
+#define arch_cmpxchg(ptr, o, n)                                \
+({                                                             \
+       __typeof__(*(ptr)) __ret;                               \
+       __smp_release_fence();                                  \
+       __ret = arch_cmpxchg_relaxed(ptr, o, n);                \
+       __smp_acquire_fence();                                  \
+       __ret;                                                  \
+})
+#endif
+
 /* we can build all atomic primitives from cmpxchg */

 #define ATOMIC_OP(op, c_op)                                            \

I think we could optimize asm-generic/atomic.h with acquire | release
| full_fence for the arch which only supports "cas" or "lrsc" (no
atomic instructions) could use "asm-generic/atomic.h" as the default
implementation.

I've omitted the structural changes and optimizations you had prepared
for riscv, but I think those can be applied atop (or applied as a
preparatory step for the ARCH_ATOMIC conversion). I'd like to keep the
two steps separate to make bisection easier.

Thanks,
Mark.

On Wed, Apr 21, 2021 at 12:53:45PM +0000, guoren@kernel.org wrote:

quoted

From: Guo Ren <redacted>

Current GENERIC_ATOMIC64 in atomic-arch-fallback.h is broken. When a 32-bit
arch use atomic-arch-fallback.h will cause compile error.

In file included from include/linux/atomic.h:81,
                    from include/linux/rcupdate.h:25,
                    from include/linux/rculist.h:11,
                    from include/linux/pid.h:5,
                    from include/linux/sched.h:14,
                    from arch/riscv/kernel/asm-offsets.c:10:
   include/linux/atomic-arch-fallback.h: In function 'arch_atomic64_inc':

quoted

quoted

include/linux/atomic-arch-fallback.h:1447:2: error: implicit declaration of function 'arch_atomic64_add'; did you mean 'arch_atomic_add'? [-Werror=implicit-function-declaration]

    1447 |  arch_atomic64_add(1, v);
         |  ^~~~~~~~~~~~~~~~~
         |  arch_atomic_add

The atomic-arch-fallback.h & atomic-fallback.h &
atomic-instrumented.h are generated by gen-atomic-fallback.sh &
gen-atomic-instrumented.sh, so just take care the bash files.

Remove the dependency of atomic-*-fallback.h in atomic64.h.

Signed-off-by: Guo Ren <redacted>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
---
 include/asm-generic/atomic-instrumented.h | 264 +++++++++++++++---------------
 include/asm-generic/atomic64.h            |  89 ++++++++++
 include/linux/atomic-arch-fallback.h      |   5 +-
 include/linux/atomic-fallback.h           |   5 +-
 scripts/atomic/gen-atomic-fallback.sh     |   3 +-
 scripts/atomic/gen-atomic-instrumented.sh |  23 ++-
 6 files changed, 251 insertions(+), 138 deletions(-)

diff --git a/include/asm-generic/atomic-instrumented.h b/include/asm-generic/atomic-instrumented.h
index 888b6cf..c9e69c6 100644
--- a/include/asm-generic/atomic-instrumented.h
+++ b/include/asm-generic/atomic-instrumented.h

@@ -831,6 +831,137 @@ atomic_dec_if_positive(atomic_t *v)
 #define atomic_dec_if_positive atomic_dec_if_positive
 #endif

+#if !defined(arch_xchg_relaxed) || defined(arch_xchg)
+#define xchg(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_xchg(__ai_ptr, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_xchg_acquire)
+#define xchg_acquire(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_xchg_acquire(__ai_ptr, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_xchg_release)
+#define xchg_release(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_xchg_release(__ai_ptr, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_xchg_relaxed)
+#define xchg_relaxed(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_xchg_relaxed(__ai_ptr, __VA_ARGS__); \
+})
+#endif
+
+#if !defined(arch_cmpxchg_relaxed) || defined(arch_cmpxchg)
+#define cmpxchg(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_cmpxchg(__ai_ptr, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_cmpxchg_acquire)
+#define cmpxchg_acquire(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_cmpxchg_acquire(__ai_ptr, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_cmpxchg_release)
+#define cmpxchg_release(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_cmpxchg_release(__ai_ptr, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_cmpxchg_relaxed)
+#define cmpxchg_relaxed(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_cmpxchg_relaxed(__ai_ptr, __VA_ARGS__); \
+})
+#endif
+
+#if !defined(arch_try_cmpxchg_relaxed) || defined(arch_try_cmpxchg)
+#define try_cmpxchg(ptr, oldp, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     typeof(oldp) __ai_oldp = (oldp); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
+     arch_try_cmpxchg(__ai_ptr, __ai_oldp, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_try_cmpxchg_acquire)
+#define try_cmpxchg_acquire(ptr, oldp, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     typeof(oldp) __ai_oldp = (oldp); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
+     arch_try_cmpxchg_acquire(__ai_ptr, __ai_oldp, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_try_cmpxchg_release)
+#define try_cmpxchg_release(ptr, oldp, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     typeof(oldp) __ai_oldp = (oldp); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
+     arch_try_cmpxchg_release(__ai_ptr, __ai_oldp, __VA_ARGS__); \
+})
+#endif
+
+#if defined(arch_try_cmpxchg_relaxed)
+#define try_cmpxchg_relaxed(ptr, oldp, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     typeof(oldp) __ai_oldp = (oldp); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
+     arch_try_cmpxchg_relaxed(__ai_ptr, __ai_oldp, __VA_ARGS__); \
+})
+#endif
+
+#define cmpxchg_local(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_cmpxchg_local(__ai_ptr, __VA_ARGS__); \
+})
+
+#define sync_cmpxchg(ptr, ...) \
+({ \
+     typeof(ptr) __ai_ptr = (ptr); \
+     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
+     arch_sync_cmpxchg(__ai_ptr, __VA_ARGS__); \
+})
+
+#ifndef CONFIG_GENERIC_ATOMIC64
 static __always_inline s64
 atomic64_read(const atomic64_t *v)
 {

@@ -1641,78 +1772,6 @@ atomic64_dec_if_positive(atomic64_t *v)
 #define atomic64_dec_if_positive atomic64_dec_if_positive
 #endif

-#if !defined(arch_xchg_relaxed) || defined(arch_xchg)
-#define xchg(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_xchg(__ai_ptr, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_xchg_acquire)
-#define xchg_acquire(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_xchg_acquire(__ai_ptr, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_xchg_release)
-#define xchg_release(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_xchg_release(__ai_ptr, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_xchg_relaxed)
-#define xchg_relaxed(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_xchg_relaxed(__ai_ptr, __VA_ARGS__); \
-})
-#endif
-
-#if !defined(arch_cmpxchg_relaxed) || defined(arch_cmpxchg)
-#define cmpxchg(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_cmpxchg(__ai_ptr, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_cmpxchg_acquire)
-#define cmpxchg_acquire(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_cmpxchg_acquire(__ai_ptr, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_cmpxchg_release)
-#define cmpxchg_release(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_cmpxchg_release(__ai_ptr, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_cmpxchg_relaxed)
-#define cmpxchg_relaxed(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_cmpxchg_relaxed(__ai_ptr, __VA_ARGS__); \
-})
-#endif
-
 #if !defined(arch_cmpxchg64_relaxed) || defined(arch_cmpxchg64)
 #define cmpxchg64(ptr, ...) \
 ({ \

@@ -1749,57 +1808,6 @@ atomic64_dec_if_positive(atomic64_t *v)
 })
 #endif

-#if !defined(arch_try_cmpxchg_relaxed) || defined(arch_try_cmpxchg)
-#define try_cmpxchg(ptr, oldp, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     typeof(oldp) __ai_oldp = (oldp); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
-     arch_try_cmpxchg(__ai_ptr, __ai_oldp, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_try_cmpxchg_acquire)
-#define try_cmpxchg_acquire(ptr, oldp, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     typeof(oldp) __ai_oldp = (oldp); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
-     arch_try_cmpxchg_acquire(__ai_ptr, __ai_oldp, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_try_cmpxchg_release)
-#define try_cmpxchg_release(ptr, oldp, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     typeof(oldp) __ai_oldp = (oldp); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
-     arch_try_cmpxchg_release(__ai_ptr, __ai_oldp, __VA_ARGS__); \
-})
-#endif
-
-#if defined(arch_try_cmpxchg_relaxed)
-#define try_cmpxchg_relaxed(ptr, oldp, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     typeof(oldp) __ai_oldp = (oldp); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     instrument_atomic_write(__ai_oldp, sizeof(*__ai_oldp)); \
-     arch_try_cmpxchg_relaxed(__ai_ptr, __ai_oldp, __VA_ARGS__); \
-})
-#endif
-
-#define cmpxchg_local(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_cmpxchg_local(__ai_ptr, __VA_ARGS__); \
-})
-
 #define cmpxchg64_local(ptr, ...) \
 ({ \
      typeof(ptr) __ai_ptr = (ptr); \

@@ -1807,13 +1815,7 @@ atomic64_dec_if_positive(atomic64_t *v)
      arch_cmpxchg64_local(__ai_ptr, __VA_ARGS__); \
 })

-#define sync_cmpxchg(ptr, ...) \
-({ \
-     typeof(ptr) __ai_ptr = (ptr); \
-     instrument_atomic_write(__ai_ptr, sizeof(*__ai_ptr)); \
-     arch_sync_cmpxchg(__ai_ptr, __VA_ARGS__); \
-})
-
+#endif
 #define cmpxchg_double(ptr, ...) \
 ({ \
      typeof(ptr) __ai_ptr = (ptr); \

@@ -1830,4 +1832,4 @@ atomic64_dec_if_positive(atomic64_t *v)
 })

 #endif /* _ASM_GENERIC_ATOMIC_INSTRUMENTED_H */
-// 4bec382e44520f4d8267e42620054db26a659ea3
+// 21c7f7e074cb2cb7e2f593fe7c8f6dec6ab9e7ea

diff --git a/include/asm-generic/atomic64.h b/include/asm-generic/atomic64.h
index 370f01d..bb5cf1e 100644
--- a/include/asm-generic/atomic64.h
+++ b/include/asm-generic/atomic64.h

@@ -34,6 +34,18 @@ extern s64 atomic64_fetch_##op(s64 a, atomic64_t *v);
 ATOMIC64_OPS(add)
 ATOMIC64_OPS(sub)

+#define atomic64_add_relaxed atomic64_add
+#define atomic64_add_acquire atomic64_add
+#define atomic64_add_release atomic64_add
+
+#define atomic64_add_return_relaxed atomic64_add_return
+#define atomic64_add_return_acquire atomic64_add_return
+#define atomic64_add_return_release atomic64_add_return
+
+#define atomic64_fetch_add_relaxed atomic64_fetch_add
+#define atomic64_fetch_add_acquire atomic64_fetch_add
+#define atomic64_fetch_add_release atomic64_fetch_add
+
 #undef ATOMIC64_OPS
 #define ATOMIC64_OPS(op)     ATOMIC64_OP(op) ATOMIC64_FETCH_OP(op)

@@ -49,8 +61,85 @@ ATOMIC64_OPS(xor)
 extern s64 atomic64_dec_if_positive(atomic64_t *v);
 #define atomic64_dec_if_positive atomic64_dec_if_positive
 extern s64 atomic64_cmpxchg(atomic64_t *v, s64 o, s64 n);
+#define atomic64_cmpxchg_relaxed atomic64_cmpxchg
+#define atomic64_cmpxchg_acquire atomic64_cmpxchg
+#define atomic64_cmpxchg_release atomic64_cmpxchg
 extern s64 atomic64_xchg(atomic64_t *v, s64 new);
+#define atomic64_xchg_relaxed atomic64_xchg
+#define atomic64_xchg_acquire atomic64_xchg
+#define atomic64_xchg_release atomic64_xchg
 extern s64 atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u);
 #define atomic64_fetch_add_unless atomic64_fetch_add_unless

+static __always_inline void
+atomic64_inc(atomic64_t *v)
+{
+     atomic64_add(1, v);
+}
+
+static __always_inline s64
+atomic64_inc_return(atomic64_t *v)
+{
+     return atomic64_add_return(1, v);
+}
+
+static __always_inline s64
+atomic64_fetch_inc(atomic64_t *v)
+{
+     return atomic64_fetch_add(1, v);
+}
+
+static __always_inline void
+atomic64_dec(atomic64_t *v)
+{
+     atomic64_sub(1, v);
+}
+
+static __always_inline s64
+atomic64_dec_return(atomic64_t *v)
+{
+     return atomic64_sub_return(1, v);
+}
+
+static __always_inline s64
+atomic64_fetch_dec(atomic64_t *v)
+{
+     return atomic64_fetch_sub(1, v);
+}
+
+static __always_inline void
+atomic64_andnot(s64 i, atomic64_t *v)
+{
+     atomic64_and(~i, v);
+}
+
+static __always_inline s64
+atomic64_fetch_andnot(s64 i, atomic64_t *v)
+{
+     return atomic64_fetch_and(~i, v);
+}
+
+static __always_inline bool
+atomic64_sub_and_test(int i, atomic64_t *v)
+{
+     return atomic64_sub_return(i, v) == 0;
+}
+
+static __always_inline bool
+atomic64_dec_and_test(atomic64_t *v)
+{
+     return atomic64_dec_return(v) == 0;
+}
+
+static __always_inline bool
+atomic64_inc_and_test(atomic64_t *v)
+{
+     return atomic64_inc_return(v) == 0;
+}
+
+static __always_inline bool
+atomic64_add_negative(s64 i, atomic64_t *v)
+{
+     return atomic64_add_return(i, v) < 0;
+}
 #endif  /*  _ASM_GENERIC_ATOMIC64_H  */

diff --git a/include/linux/atomic-arch-fallback.h b/include/linux/atomic-arch-fallback.h
index a3dba31..2f1db6a 100644
--- a/include/linux/atomic-arch-fallback.h
+++ b/include/linux/atomic-arch-fallback.h

@@ -1252,7 +1252,7 @@ arch_atomic_dec_if_positive(atomic_t *v)

 #ifdef CONFIG_GENERIC_ATOMIC64
 #include <asm-generic/atomic64.h>
-#endif
+#else

 #ifndef arch_atomic64_read_acquire
 static __always_inline s64

@@ -2357,5 +2357,6 @@ arch_atomic64_dec_if_positive(atomic64_t *v)
 #define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
 #endif

+#endif /* CONFIG_GENERIC_ATOMIC64 */
 #endif /* _LINUX_ATOMIC_FALLBACK_H */
-// cca554917d7ea73d5e3e7397dd70c484cad9b2c4
+// ae31a21075855e67a9b2927f8241dedddafda046

diff --git a/include/linux/atomic-fallback.h b/include/linux/atomic-fallback.h
index 2a3f55d..7dda483 100644
--- a/include/linux/atomic-fallback.h
+++ b/include/linux/atomic-fallback.h

@@ -1369,7 +1369,7 @@ atomic_dec_if_positive(atomic_t *v)

 #ifdef CONFIG_GENERIC_ATOMIC64
 #include <asm-generic/atomic64.h>
-#endif
+#else

 #define arch_atomic64_read atomic64_read
 #define arch_atomic64_read_acquire atomic64_read_acquire

@@ -2591,5 +2591,6 @@ atomic64_dec_if_positive(atomic64_t *v)
 #define atomic64_dec_if_positive atomic64_dec_if_positive
 #endif

+#endif /* CONFIG_GENERIC_ATOMIC64 */
 #endif /* _LINUX_ATOMIC_FALLBACK_H */
-// d78e6c293c661c15188f0ec05bce45188c8d5892
+// b809c8e3c88910826f765bdba4a74f21c527029d

diff --git a/scripts/atomic/gen-atomic-fallback.sh b/scripts/atomic/gen-atomic-fallback.sh
index 317a6ce..8b7a685 100755
--- a/scripts/atomic/gen-atomic-fallback.sh
+++ b/scripts/atomic/gen-atomic-fallback.sh

@@ -247,7 +247,7 @@ done
 cat <<EOF
 #ifdef CONFIG_GENERIC_ATOMIC64
 #include <asm-generic/atomic64.h>
-#endif
+#else

 EOF

@@ -256,5 +256,6 @@ grep '^[a-z]' "$1" | while read name meta args; do
 done

 cat <<EOF
+#endif /* CONFIG_GENERIC_ATOMIC64 */
 #endif /* _LINUX_ATOMIC_FALLBACK_H */
 EOF

diff --git a/scripts/atomic/gen-atomic-instrumented.sh b/scripts/atomic/gen-atomic-instrumented.sh
index 5766ffc..1f2a58b 100755
--- a/scripts/atomic/gen-atomic-instrumented.sh
+++ b/scripts/atomic/gen-atomic-instrumented.sh

@@ -182,21 +182,40 @@ grep '^[a-z]' "$1" | while read name meta args; do
      gen_proto "${meta}" "${name}" "atomic" "int" ${args}
 done

+for xchg in "xchg" "cmpxchg" "try_cmpxchg"; do
+     for order in "" "_acquire" "_release" "_relaxed"; do
+             gen_optional_xchg "${xchg}" "${order}"
+     done
+done
+
+for xchg in "cmpxchg_local" "sync_cmpxchg"; do
+     gen_xchg "${xchg}" ""
+     printf "\n"
+done
+
+cat <<EOF
+#ifndef CONFIG_GENERIC_ATOMIC64
+EOF
+
 grep '^[a-z]' "$1" | while read name meta args; do
      gen_proto "${meta}" "${name}" "atomic64" "s64" ${args}
 done

-for xchg in "xchg" "cmpxchg" "cmpxchg64" "try_cmpxchg"; do
+for xchg in "cmpxchg64"; do
      for order in "" "_acquire" "_release" "_relaxed"; do
              gen_optional_xchg "${xchg}" "${order}"
      done
 done

-for xchg in "cmpxchg_local" "cmpxchg64_local" "sync_cmpxchg"; do
+for xchg in "cmpxchg64_local"; do
      gen_xchg "${xchg}" ""
      printf "\n"
 done

+cat <<EOF
+#endif
+EOF
+
 gen_xchg "cmpxchg_double" "2 * "

 printf "\n\n"
--

2.7.4

--
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/