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

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

[guoren]

From: Guo Ren <guoren@linux.alibaba.com>

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 <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
---
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

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

[Mark Rutland]

On Sat, Nov 25, 2023 at 08:39:21PM -0500, guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
> 
> 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 <guoren@linux.alibaba.com>
> Signed-off-by: Guo Ren <guoren@kernel.org>
> ---
> 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
> 

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

[Guo Ren]

On Mon, Nov 27, 2023 at 7:56 PM Mark Rutland <mark.rutland@arm.com> wrote:
>
> On Sat, Nov 25, 2023 at 08:39:21PM -0500, guoren@kernel.org wrote:
> > From: Guo Ren <guoren@linux.alibaba.com>
> >
> > 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 <guoren@linux.alibaba.com>
> > Signed-off-by: Guo Ren <guoren@kernel.org>
> > ---
> > 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