2023-11-26 01:39:54

by Guo Ren

Subject: [PATCH V3] locking/atomic: scripts: Exclude arch_atomic(64)_read(set) mappings

From: Guo Ren <[email protected]>

The definitions of atomic(64)_read(set) are relax version, and using
them for acquire and release is incorrect, so exclude these mappings.

Signed-off-by: Guo Ren <[email protected]>
Signed-off-by: Guo Ren <[email protected]>
---
Changelog:
v3:
- Minimize modification on atomic(64)_read(set)

v2:
- Use gen-atomic-fallback.sh instead of header modification
---
include/linux/atomic/atomic-arch-fallback.h | 10 +---------
scripts/atomic/gen-atomic-fallback.sh | 3 ++-
2 files changed, 3 insertions(+), 10 deletions(-)

diff --git a/include/linux/atomic/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h
index 18f5744dfb5d..b83ef19da13d 100644
--- a/include/linux/atomic/atomic-arch-fallback.h
+++ b/include/linux/atomic/atomic-arch-fallback.h
@@ -459,8 +459,6 @@ raw_atomic_read_acquire(const atomic_t *v)
{
#if defined(arch_atomic_read_acquire)
return arch_atomic_read_acquire(v);
-#elif defined(arch_atomic_read)
- return arch_atomic_read(v);
#else
int ret;

@@ -508,8 +506,6 @@ raw_atomic_set_release(atomic_t *v, int i)
{
#if defined(arch_atomic_set_release)
arch_atomic_set_release(v, i);
-#elif defined(arch_atomic_set)
- arch_atomic_set(v, i);
#else
if (__native_word(atomic_t)) {
smp_store_release(&(v)->counter, i);
@@ -2575,8 +2571,6 @@ raw_atomic64_read_acquire(const atomic64_t *v)
{
#if defined(arch_atomic64_read_acquire)
return arch_atomic64_read_acquire(v);
-#elif defined(arch_atomic64_read)
- return arch_atomic64_read(v);
#else
s64 ret;

@@ -2624,8 +2618,6 @@ raw_atomic64_set_release(atomic64_t *v, s64 i)
{
#if defined(arch_atomic64_set_release)
arch_atomic64_set_release(v, i);
-#elif defined(arch_atomic64_set)
- arch_atomic64_set(v, i);
#else
if (__native_word(atomic64_t)) {
smp_store_release(&(v)->counter, i);
@@ -4657,4 +4649,4 @@ raw_atomic64_dec_if_positive(atomic64_t *v)
}

#endif /* _LINUX_ATOMIC_FALLBACK_H */
-// 202b45c7db600ce36198eb1f1fc2c2d5268ace2d
+// 2fdd6702823fa842f9cea57a002e6e4476ae780c
diff --git a/scripts/atomic/gen-atomic-fallback.sh b/scripts/atomic/gen-atomic-fallback.sh
index c0c8a85d7c81..282a1d3c41d4 100755
--- a/scripts/atomic/gen-atomic-fallback.sh
+++ b/scripts/atomic/gen-atomic-fallback.sh
@@ -102,7 +102,8 @@ gen_proto_order_variant()
fi

# Allow ACQUIRE/RELEASE/RELAXED ops to be defined in terms of FULL ops
- if [ ! -z "${order}" ]; then
+ # Exclude arch_atomic(64)_read(set) mappings because these are not FULL ops.
+ if [ ! -z "${order}" ] && [ "${name}" != "read" ] && [ "${name}" != "set" ]; then
printf "#elif defined(arch_${basename})\n"
printf "\t${retstmt}arch_${basename}(${args});\n"
fi
--
2.36.1

2023-11-27 11:56:45

by Mark Rutland

Subject: Re: [PATCH V3] locking/atomic: scripts: Exclude arch_atomic(64)_read(set) mappings

On Sat, Nov 25, 2023 at 08:39:21PM -0500, [email protected] wrote:
> From: Guo Ren <[email protected]>
>
> The definitions of atomic(64)_read(set) are relax version, and using
> them for acquire and release is incorrect, so exclude these mappings.

This was fixed by commit:

6d2779ecaeb56f92 ("locking/atomic: scripts: fix fallback ifdeffery")

That commit was in v6.6-rc3, and has been backported to stable kernels.

I think you're using an old kernel as a base.

Thanks,
Mark.

>
> Signed-off-by: Guo Ren <[email protected]>
> Signed-off-by: Guo Ren <[email protected]>
> ---
> Changelog:
> v3:
> - Minimize modification on atomic(64)_read(set)
>
> v2:
> - Use gen-atomic-fallback.sh instead of header modification
> ---
> include/linux/atomic/atomic-arch-fallback.h | 10 +---------
> scripts/atomic/gen-atomic-fallback.sh | 3 ++-
> 2 files changed, 3 insertions(+), 10 deletions(-)
>
> diff --git a/include/linux/atomic/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h
> index 18f5744dfb5d..b83ef19da13d 100644
> --- a/include/linux/atomic/atomic-arch-fallback.h
> +++ b/include/linux/atomic/atomic-arch-fallback.h
> @@ -459,8 +459,6 @@ raw_atomic_read_acquire(const atomic_t *v)
> {
> #if defined(arch_atomic_read_acquire)
> return arch_atomic_read_acquire(v);
> -#elif defined(arch_atomic_read)
> - return arch_atomic_read(v);
> #else
> int ret;
>
> @@ -508,8 +506,6 @@ raw_atomic_set_release(atomic_t *v, int i)
> {
> #if defined(arch_atomic_set_release)
> arch_atomic_set_release(v, i);
> -#elif defined(arch_atomic_set)
> - arch_atomic_set(v, i);
> #else
> if (__native_word(atomic_t)) {
> smp_store_release(&(v)->counter, i);
> @@ -2575,8 +2571,6 @@ raw_atomic64_read_acquire(const atomic64_t *v)
> {
> #if defined(arch_atomic64_read_acquire)
> return arch_atomic64_read_acquire(v);
> -#elif defined(arch_atomic64_read)
> - return arch_atomic64_read(v);
> #else
> s64 ret;
>
> @@ -2624,8 +2618,6 @@ raw_atomic64_set_release(atomic64_t *v, s64 i)
> {
> #if defined(arch_atomic64_set_release)
> arch_atomic64_set_release(v, i);
> -#elif defined(arch_atomic64_set)
> - arch_atomic64_set(v, i);
> #else
> if (__native_word(atomic64_t)) {
> smp_store_release(&(v)->counter, i);
> @@ -4657,4 +4649,4 @@ raw_atomic64_dec_if_positive(atomic64_t *v)
> }
>
> #endif /* _LINUX_ATOMIC_FALLBACK_H */
> -// 202b45c7db600ce36198eb1f1fc2c2d5268ace2d
> +// 2fdd6702823fa842f9cea57a002e6e4476ae780c
> diff --git a/scripts/atomic/gen-atomic-fallback.sh b/scripts/atomic/gen-atomic-fallback.sh
> index c0c8a85d7c81..282a1d3c41d4 100755
> --- a/scripts/atomic/gen-atomic-fallback.sh
> +++ b/scripts/atomic/gen-atomic-fallback.sh
> @@ -102,7 +102,8 @@ gen_proto_order_variant()
> fi
>
> # Allow ACQUIRE/RELEASE/RELAXED ops to be defined in terms of FULL ops
> - if [ ! -z "${order}" ]; then
> + # Exclude arch_atomic(64)_read(set) mappings because these are not FULL ops.
> + if [ ! -z "${order}" ] && [ "${name}" != "read" ] && [ "${name}" != "set" ]; then
> printf "#elif defined(arch_${basename})\n"
> printf "\t${retstmt}arch_${basename}(${args});\n"
> fi
> --
> 2.36.1
>

2023-11-27 13:06:38

by Guo Ren

Subject: Re: [PATCH V3] locking/atomic: scripts: Exclude arch_atomic(64)_read(set) mappings

On Mon, Nov 27, 2023 at 7:56 PM Mark Rutland <[email protected]> wrote:
>
> On Sat, Nov 25, 2023 at 08:39:21PM -0500, [email protected] wrote:
> > From: Guo Ren <[email protected]>
> >
> > The definitions of atomic(64)_read(set) are relax version, and using
> > them for acquire and release is incorrect, so exclude these mappings.
>
> This was fixed by commit:
>
> 6d2779ecaeb56f92 ("locking/atomic: scripts: fix fallback ifdeffery")
>
> That commit was in v6.6-rc3, and has been backported to stable kernels.
>
> I think you're using an old kernel as a base.
okay, thx for mentioning it.

>
> Thanks,
> Mark.
>
> >
> > Signed-off-by: Guo Ren <[email protected]>
> > Signed-off-by: Guo Ren <[email protected]>
> > ---
> > Changelog:
> > v3:
> > - Minimize modification on atomic(64)_read(set)
> >
> > v2:
> > - Use gen-atomic-fallback.sh instead of header modification
> > ---
> > include/linux/atomic/atomic-arch-fallback.h | 10 +---------
> > scripts/atomic/gen-atomic-fallback.sh | 3 ++-
> > 2 files changed, 3 insertions(+), 10 deletions(-)
> >
> > diff --git a/include/linux/atomic/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h
> > index 18f5744dfb5d..b83ef19da13d 100644
> > --- a/include/linux/atomic/atomic-arch-fallback.h
> > +++ b/include/linux/atomic/atomic-arch-fallback.h
> > @@ -459,8 +459,6 @@ raw_atomic_read_acquire(const atomic_t *v)
> > {
> > #if defined(arch_atomic_read_acquire)
> > return arch_atomic_read_acquire(v);
> > -#elif defined(arch_atomic_read)
> > - return arch_atomic_read(v);
> > #else
> > int ret;
> >
> > @@ -508,8 +506,6 @@ raw_atomic_set_release(atomic_t *v, int i)
> > {
> > #if defined(arch_atomic_set_release)
> > arch_atomic_set_release(v, i);
> > -#elif defined(arch_atomic_set)
> > - arch_atomic_set(v, i);
> > #else
> > if (__native_word(atomic_t)) {
> > smp_store_release(&(v)->counter, i);
> > @@ -2575,8 +2571,6 @@ raw_atomic64_read_acquire(const atomic64_t *v)
> > {
> > #if defined(arch_atomic64_read_acquire)
> > return arch_atomic64_read_acquire(v);
> > -#elif defined(arch_atomic64_read)
> > - return arch_atomic64_read(v);
> > #else
> > s64 ret;
> >
> > @@ -2624,8 +2618,6 @@ raw_atomic64_set_release(atomic64_t *v, s64 i)
> > {
> > #if defined(arch_atomic64_set_release)
> > arch_atomic64_set_release(v, i);
> > -#elif defined(arch_atomic64_set)
> > - arch_atomic64_set(v, i);
> > #else
> > if (__native_word(atomic64_t)) {
> > smp_store_release(&(v)->counter, i);
> > @@ -4657,4 +4649,4 @@ raw_atomic64_dec_if_positive(atomic64_t *v)
> > }
> >
> > #endif /* _LINUX_ATOMIC_FALLBACK_H */
> > -// 202b45c7db600ce36198eb1f1fc2c2d5268ace2d
> > +// 2fdd6702823fa842f9cea57a002e6e4476ae780c
> > diff --git a/scripts/atomic/gen-atomic-fallback.sh b/scripts/atomic/gen-atomic-fallback.sh
> > index c0c8a85d7c81..282a1d3c41d4 100755
> > --- a/scripts/atomic/gen-atomic-fallback.sh
> > +++ b/scripts/atomic/gen-atomic-fallback.sh
> > @@ -102,7 +102,8 @@ gen_proto_order_variant()
> > fi
> >
> > # Allow ACQUIRE/RELEASE/RELAXED ops to be defined in terms of FULL ops
> > - if [ ! -z "${order}" ]; then
> > + # Exclude arch_atomic(64)_read(set) mappings because these are not FULL ops.
> > + if [ ! -z "${order}" ] && [ "${name}" != "read" ] && [ "${name}" != "set" ]; then
> > printf "#elif defined(arch_${basename})\n"
> > printf "\t${retstmt}arch_${basename}(${args});\n"
> > fi
> > --
> > 2.36.1
> >



--
Best Regards
Guo Ren