[PATCH v2 0/3] list: Add hlist_count_nodes()

[PATCH v2 0/3] list: Add hlist_count_nodes()

[Pierre Gondois]

v2:
- Add usages of the function to avoid considering it as dead code.
v1:
- https://lore.kernel.org/all/20240103090241.164817-1-pierre.gondois@arm.com/

Add a generic hlist_count_nodes() function.

This function aims to be used in a private module. As suggested by
Marco, having it used would avoid to consider it as dead code.
Thus, add some usages of the function in two drivers.

Pierre Gondois (3):
  list: Add hlist_count_nodes()
  binder: Use of hlist_count_nodes()
  bcache: Use of hlist_count_nodes()

 drivers/android/binder.c  |  4 +---
 drivers/md/bcache/sysfs.c |  8 +-------
 include/linux/list.h      | 15 +++++++++++++++
 3 files changed, 17 insertions(+), 10 deletions(-)

-- 
2.25.1

[PATCH v2 1/3] list: Add hlist_count_nodes()

[Pierre Gondois]

Add a function to count nodes in a hlist. hlist_count_nodes()
is similar to list_count_nodes().

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
---
 include/linux/list.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/include/linux/list.h b/include/linux/list.h
index 1837caedf723..0f1b1d4a2e2e 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -1175,4 +1175,19 @@ static inline void hlist_move_list(struct hlist_head *old,
 	     pos && ({ n = pos->member.next; 1; });			\
 	     pos = hlist_entry_safe(n, typeof(*pos), member))
 
+/**
+ * hlist_count_nodes - count nodes in the hlist
+ * @head:	the head for your hlist.
+ */
+static inline size_t hlist_count_nodes(struct hlist_head *head)
+{
+	struct hlist_node *pos;
+	size_t count = 0;
+
+	hlist_for_each(pos, head)
+		count++;
+
+	return count;
+}
+
 #endif
-- 
2.25.1

Re: [PATCH v2 1/3] list: Add hlist_count_nodes()

[Carlos Llamas]

On Thu, Jan 04, 2024 at 05:49:33PM +0100, Pierre Gondois wrote:
> Add a function to count nodes in a hlist. hlist_count_nodes()
> is similar to list_count_nodes().
> 
> Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
> ---
>  include/linux/list.h | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/include/linux/list.h b/include/linux/list.h
> index 1837caedf723..0f1b1d4a2e2e 100644
> --- a/include/linux/list.h
> +++ b/include/linux/list.h
> @@ -1175,4 +1175,19 @@ static inline void hlist_move_list(struct hlist_head *old,
>  	     pos && ({ n = pos->member.next; 1; });			\
>  	     pos = hlist_entry_safe(n, typeof(*pos), member))
>  
> +/**
> + * hlist_count_nodes - count nodes in the hlist
> + * @head:	the head for your hlist.
> + */
> +static inline size_t hlist_count_nodes(struct hlist_head *head)
> +{
> +	struct hlist_node *pos;
> +	size_t count = 0;
> +
> +	hlist_for_each(pos, head)
> +		count++;
> +
> +	return count;
> +}
> +
>  #endif
> -- 
> 2.25.1
> 

Looks good.

Reviewed-by: Carlos Llamas <cmllamas@google.com>

Re: [PATCH v2 1/3] list: Add hlist_count_nodes()

[Coly Li]

On Thu, Jan 04, 2024 at 05:49:33PM +0100, Pierre Gondois wrote:
> Add a function to count nodes in a hlist. hlist_count_nodes()
> is similar to list_count_nodes().
> 
> Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>

Acked-by: Coly Li <colyli@suse.de>

Thanks.

> ---
>  include/linux/list.h | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/include/linux/list.h b/include/linux/list.h
> index 1837caedf723..0f1b1d4a2e2e 100644
> --- a/include/linux/list.h
> +++ b/include/linux/list.h
> @@ -1175,4 +1175,19 @@ static inline void hlist_move_list(struct hlist_head *old,
>  	     pos && ({ n = pos->member.next; 1; });			\
>  	     pos = hlist_entry_safe(n, typeof(*pos), member))
>  
> +/**
> + * hlist_count_nodes - count nodes in the hlist
> + * @head:	the head for your hlist.
> + */
> +static inline size_t hlist_count_nodes(struct hlist_head *head)
> +{
> +	struct hlist_node *pos;
> +	size_t count = 0;
> +
> +	hlist_for_each(pos, head)
> +		count++;
> +
> +	return count;
> +}
> +
>  #endif
> -- 
> 2.25.1
> 
> 

-- 
Coly Li

[PATCH v2 2/3] binder: Use of hlist_count_nodes()

[Pierre Gondois]

Make use of the newly added hlist_count_nodes().

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
---
 drivers/android/binder.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 92128aae2d06..f9ca4d58d825 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -6077,9 +6077,7 @@ static void print_binder_node_nilocked(struct seq_file *m,
 	struct binder_work *w;
 	int count;
 
-	count = 0;
-	hlist_for_each_entry(ref, &node->refs, node_entry)
-		count++;
+	count = hlist_count_nodes(&node->refs);
 
 	seq_printf(m, "  node %d: u%016llx c%016llx hs %d hw %d ls %d lw %d is %d iw %d tr %d",
 		   node->debug_id, (u64)node->ptr, (u64)node->cookie,
-- 
2.25.1

Re: [PATCH v2 2/3] binder: Use of hlist_count_nodes()

[Carlos Llamas]

On Thu, Jan 04, 2024 at 05:49:34PM +0100, Pierre Gondois wrote:
> Make use of the newly added hlist_count_nodes().
> 
> Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
> ---
>  drivers/android/binder.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 92128aae2d06..f9ca4d58d825 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -6077,9 +6077,7 @@ static void print_binder_node_nilocked(struct seq_file *m,
>  	struct binder_work *w;
>  	int count;
>  
> -	count = 0;
> -	hlist_for_each_entry(ref, &node->refs, node_entry)
> -		count++;
> +	count = hlist_count_nodes(&node->refs);
>  
>  	seq_printf(m, "  node %d: u%016llx c%016llx hs %d hw %d ls %d lw %d is %d iw %d tr %d",
>  		   node->debug_id, (u64)node->ptr, (u64)node->cookie,
> -- 
> 2.25.1
> 

Looks good to me!

Acked-by: Carlos Llamas <cmllamas@google.com>

[PATCH v2 3/3] bcache: Use of hlist_count_nodes()

[Pierre Gondois]

Make use of the newly added hlist_count_nodes().

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
---
 drivers/md/bcache/sysfs.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index a438efb66069..6956beb55326 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -702,13 +702,7 @@ static unsigned int bch_cache_max_chain(struct cache_set *c)
 	for (h = c->bucket_hash;
 	     h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
 	     h++) {
-		unsigned int i = 0;
-		struct hlist_node *p;
-
-		hlist_for_each(p, h)
-			i++;
-
-		ret = max(ret, i);
+		ret = max(ret, hlist_count_nodes(h));
 	}
 
 	mutex_unlock(&c->bucket_lock);
-- 
2.25.1

Re: [PATCH v2 3/3] bcache: Use of hlist_count_nodes()

[Coly Li]

On Thu, Jan 04, 2024 at 05:49:35PM +0100, Pierre Gondois wrote:
> Make use of the newly added hlist_count_nodes().
> 
> Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>

Acked-by: Coly Li <colyli@suse.de>

Thanks.

> ---
>  drivers/md/bcache/sysfs.c | 8 +-------
>  1 file changed, 1 insertion(+), 7 deletions(-)
> 
> diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
> index a438efb66069..6956beb55326 100644
> --- a/drivers/md/bcache/sysfs.c
> +++ b/drivers/md/bcache/sysfs.c
> @@ -702,13 +702,7 @@ static unsigned int bch_cache_max_chain(struct cache_set *c)
>  	for (h = c->bucket_hash;
>  	     h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
>  	     h++) {
> -		unsigned int i = 0;
> -		struct hlist_node *p;
> -
> -		hlist_for_each(p, h)
> -			i++;
> -
> -		ret = max(ret, i);
> +		ret = max(ret, hlist_count_nodes(h));
>  	}
>  
>  	mutex_unlock(&c->bucket_lock);
> -- 
> 2.25.1
> 
> 

-- 
Coly Li

Re: [PATCH v2 3/3] bcache: Use of hlist_count_nodes()

[Andy Shevchenko]

On Thu, Jan 04, 2024 at 05:49:35PM +0100, Pierre Gondois wrote:
> Make use of the newly added hlist_count_nodes().

...

>  	for (h = c->bucket_hash;
>  	     h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
>  	     h++) {
> -		unsigned int i = 0;
> -		struct hlist_node *p;
> -
> -		hlist_for_each(p, h)
> -			i++;
> -
> -		ret = max(ret, i);
> +		ret = max(ret, hlist_count_nodes(h));
>  	}

After this you probably may drop {}.


-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 0/3] list: Add hlist_count_nodes()

[Marco Elver]

On Thu, 4 Jan 2024 at 17:50, Pierre Gondois <pierre.gondois@arm.com> wrote:
>
> v2:
> - Add usages of the function to avoid considering it as dead code.
> v1:
> - https://lore.kernel.org/all/20240103090241.164817-1-pierre.gondois@arm.com/
>
> Add a generic hlist_count_nodes() function.
>
> This function aims to be used in a private module. As suggested by
> Marco, having it used would avoid to consider it as dead code.
> Thus, add some usages of the function in two drivers.

Whether or not it's used in a private module is probably irrelevant
from an upstream perspective.

But this is a reasonable cleanup, and at the same time adds API
symmetry with the already existing list_count_nodes().

> Pierre Gondois (3):
>   list: Add hlist_count_nodes()
>   binder: Use of hlist_count_nodes()
>   bcache: Use of hlist_count_nodes()
>
>  drivers/android/binder.c  |  4 +---
>  drivers/md/bcache/sysfs.c |  8 +-------
>  include/linux/list.h      | 15 +++++++++++++++
>  3 files changed, 17 insertions(+), 10 deletions(-)

For the series:

Acked-by: Marco Elver <elver@google.com>

Thanks.

Re: [PATCH v2 0/3] list: Add hlist_count_nodes()

[Marco Elver]

On Thu, 4 Jan 2024 at 18:16, Marco Elver <elver@google.com> wrote:
> On Thu, 4 Jan 2024 at 17:50, Pierre Gondois <pierre.gondois@arm.com> wrote:
> >
> > v2:
> > - Add usages of the function to avoid considering it as dead code.
> > v1:
> > - https://lore.kernel.org/all/20240103090241.164817-1-pierre.gondois@arm.com/
> >
> > Add a generic hlist_count_nodes() function.
> >
> > This function aims to be used in a private module. As suggested by
> > Marco, having it used would avoid to consider it as dead code.
> > Thus, add some usages of the function in two drivers.
>
> Whether or not it's used in a private module is probably irrelevant
> from an upstream perspective.
>
> But this is a reasonable cleanup, and at the same time adds API
> symmetry with the already existing list_count_nodes().
>
> > Pierre Gondois (3):
> >   list: Add hlist_count_nodes()
> >   binder: Use of hlist_count_nodes()
> >   bcache: Use of hlist_count_nodes()
> >
> >  drivers/android/binder.c  |  4 +---
> >  drivers/md/bcache/sysfs.c |  8 +-------
> >  include/linux/list.h      | 15 +++++++++++++++
> >  3 files changed, 17 insertions(+), 10 deletions(-)
>
> For the series:
>
> Acked-by: Marco Elver <elver@google.com>

Btw, there doesn't appear to be a clear maintainer or tree for
include/linux/list.h. Since there have been several Acks/Reviews by
now, did you have a particular tree in mind?
Perhaps Andrew (+Cc) can help.

Thanks,
-- Marco

Re: [PATCH v2 0/3] list: Add hlist_count_nodes()

[Andy Shevchenko]

On Thu, Jan 04, 2024 at 05:49:32PM +0100, Pierre Gondois wrote:
> v2:
> - Add usages of the function to avoid considering it as dead code.
> v1:
> - https://lore.kernel.org/all/20240103090241.164817-1-pierre.gondois@arm.com/
> 
> Add a generic hlist_count_nodes() function.
> 
> This function aims to be used in a private module. As suggested by
> Marco, having it used would avoid to consider it as dead code.
> Thus, add some usages of the function in two drivers.

With or without a nit-pick being addressed,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko