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[PATCH v5 03/12] mm: constify zone related test functions for improved const-correctness

Max Kellermann posted 12 patches 3 months, 1 week ago
There is a newer version of this series
[PATCH v5 03/12] mm: constify zone related test functions for improved const-correctness
Posted by Max Kellermann 3 months, 1 week ago 
We select certain test functions which either invoke each other,
functions that are already const-ified, or no further functions.

It is therefore relatively trivial to const-ify them, which
provides a basis for further const-ification further up the call
stack.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
---
 include/linux/mmzone.h | 42 +++++++++++++++++++++---------------------
 1 file changed, 21 insertions(+), 21 deletions(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index f3272ef5131b..9a25fb1ade82 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1104,7 +1104,7 @@ static inline unsigned long promo_wmark_pages(const struct zone *z)
 	return wmark_pages(z, WMARK_PROMO);
 }
 
-static inline unsigned long zone_managed_pages(struct zone *zone)
+static inline unsigned long zone_managed_pages(const struct zone *const zone)
 {
 	return (unsigned long)atomic_long_read(&zone->managed_pages);
 }
@@ -1128,12 +1128,12 @@ static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)
 	return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);
 }
 
-static inline bool zone_is_initialized(struct zone *zone)
+static inline bool zone_is_initialized(const struct zone *const zone)
 {
 	return zone->initialized;
 }
 
-static inline bool zone_is_empty(struct zone *zone)
+static inline bool zone_is_empty(const struct zone *const zone)
 {
 	return zone->spanned_pages == 0;
 }
@@ -1273,7 +1273,7 @@ static inline bool folio_is_zone_movable(const struct folio *folio)
  * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty
  * intersection with the given zone
  */
-static inline bool zone_intersects(struct zone *zone,
+static inline bool zone_intersects(const struct zone *const zone,
 		unsigned long start_pfn, unsigned long nr_pages)
 {
 	if (zone_is_empty(zone))
@@ -1581,12 +1581,12 @@ static inline int local_memory_node(int node_id) { return node_id; };
 #define zone_idx(zone)		((zone) - (zone)->zone_pgdat->node_zones)
 
 #ifdef CONFIG_ZONE_DEVICE
-static inline bool zone_is_zone_device(struct zone *zone)
+static inline bool zone_is_zone_device(const struct zone *const zone)
 {
 	return zone_idx(zone) == ZONE_DEVICE;
 }
 #else
-static inline bool zone_is_zone_device(struct zone *zone)
+static inline bool zone_is_zone_device(const struct zone *const zone)
 {
 	return false;
 }
@@ -1598,19 +1598,19 @@ static inline bool zone_is_zone_device(struct zone *zone)
  * populated_zone(). If the whole zone is reserved then we can easily
  * end up with populated_zone() && !managed_zone().
  */
-static inline bool managed_zone(struct zone *zone)
+static inline bool managed_zone(const struct zone *const zone)
 {
 	return zone_managed_pages(zone);
 }
 
 /* Returns true if a zone has memory */
-static inline bool populated_zone(struct zone *zone)
+static inline bool populated_zone(const struct zone *const zone)
 {
 	return zone->present_pages;
 }
 
 #ifdef CONFIG_NUMA
-static inline int zone_to_nid(struct zone *zone)
+static inline int zone_to_nid(const struct zone *const zone)
 {
 	return zone->node;
 }
@@ -1620,7 +1620,7 @@ static inline void zone_set_nid(struct zone *zone, int nid)
 	zone->node = nid;
 }
 #else
-static inline int zone_to_nid(struct zone *zone)
+static inline int zone_to_nid(const struct zone *zone)
 {
 	return 0;
 }
@@ -1647,7 +1647,7 @@ static inline int is_highmem_idx(enum zone_type idx)
  * @zone: pointer to struct zone variable
  * Return: 1 for a highmem zone, 0 otherwise
  */
-static inline int is_highmem(struct zone *zone)
+static inline int is_highmem(const struct zone *const zone)
 {
 	return is_highmem_idx(zone_idx(zone));
 }
@@ -1713,12 +1713,12 @@ static inline struct zone *zonelist_zone(struct zoneref *zoneref)
 	return zoneref->zone;
 }
 
-static inline int zonelist_zone_idx(struct zoneref *zoneref)
+static inline int zonelist_zone_idx(const struct zoneref *const zoneref)
 {
 	return zoneref->zone_idx;
 }
 
-static inline int zonelist_node_idx(struct zoneref *zoneref)
+static inline int zonelist_node_idx(const struct zoneref *const zoneref)
 {
 	return zone_to_nid(zoneref->zone);
 }
@@ -2021,7 +2021,7 @@ static inline struct page *__section_mem_map_addr(struct mem_section *section)
 	return (struct page *)map;
 }
 
-static inline int present_section(struct mem_section *section)
+static inline int present_section(const struct mem_section *const section)
 {
 	return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
 }
@@ -2031,12 +2031,12 @@ static inline int present_section_nr(unsigned long nr)
 	return present_section(__nr_to_section(nr));
 }
 
-static inline int valid_section(struct mem_section *section)
+static inline int valid_section(const struct mem_section *const section)
 {
 	return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
 }
 
-static inline int early_section(struct mem_section *section)
+static inline int early_section(const struct mem_section *const section)
 {
 	return (section && (section->section_mem_map & SECTION_IS_EARLY));
 }
@@ -2046,27 +2046,27 @@ static inline int valid_section_nr(unsigned long nr)
 	return valid_section(__nr_to_section(nr));
 }
 
-static inline int online_section(struct mem_section *section)
+static inline int online_section(const struct mem_section *const section)
 {
 	return (section && (section->section_mem_map & SECTION_IS_ONLINE));
 }
 
 #ifdef CONFIG_ZONE_DEVICE
-static inline int online_device_section(struct mem_section *section)
+static inline int online_device_section(const struct mem_section *const section)
 {
 	unsigned long flags = SECTION_IS_ONLINE | SECTION_TAINT_ZONE_DEVICE;
 
 	return section && ((section->section_mem_map & flags) == flags);
 }
 #else
-static inline int online_device_section(struct mem_section *section)
+static inline int online_device_section(const struct mem_section *const section)
 {
 	return 0;
 }
 #endif
 
 #ifdef CONFIG_SPARSEMEM_VMEMMAP_PREINIT
-static inline int preinited_vmemmap_section(struct mem_section *section)
+static inline int preinited_vmemmap_section(const struct mem_section *const section)
 {
 	return (section &&
 		(section->section_mem_map & SECTION_IS_VMEMMAP_PREINIT));
@@ -2076,7 +2076,7 @@ void sparse_vmemmap_init_nid_early(int nid);
 void sparse_vmemmap_init_nid_late(int nid);
 
 #else
-static inline int preinited_vmemmap_section(struct mem_section *section)
+static inline int preinited_vmemmap_section(const struct mem_section *const section)
 {
 	return 0;
 }
-- 
2.47.2
Re: [PATCH v5 03/12] mm: constify zone related test functions for improved const-correctness
Posted by Lorenzo Stoakes 3 months, 1 week ago 
On Mon, Sep 01, 2025 at 02:30:19PM +0200, Max Kellermann wrote:
> We select certain test functions which either invoke each other,
> functions that are already const-ified, or no further functions.
>
> It is therefore relatively trivial to const-ify them, which
> provides a basis for further const-ification further up the call
> stack.
>
> Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>

On basis that we figure out whether we want the "const <type> *const <param>"
thing or not, this otherwise LGTM so:

Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>

> ---
>  include/linux/mmzone.h | 42 +++++++++++++++++++++---------------------
>  1 file changed, 21 insertions(+), 21 deletions(-)
>
> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
> index f3272ef5131b..9a25fb1ade82 100644
> --- a/include/linux/mmzone.h
> +++ b/include/linux/mmzone.h
> @@ -1104,7 +1104,7 @@ static inline unsigned long promo_wmark_pages(const struct zone *z)
>  	return wmark_pages(z, WMARK_PROMO);
>  }
>
> -static inline unsigned long zone_managed_pages(struct zone *zone)
> +static inline unsigned long zone_managed_pages(const struct zone *const zone)
>  {
>  	return (unsigned long)atomic_long_read(&zone->managed_pages);
>  }
> @@ -1128,12 +1128,12 @@ static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)
>  	return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);
>  }
>
> -static inline bool zone_is_initialized(struct zone *zone)
> +static inline bool zone_is_initialized(const struct zone *const zone)
>  {
>  	return zone->initialized;
>  }
>
> -static inline bool zone_is_empty(struct zone *zone)
> +static inline bool zone_is_empty(const struct zone *const zone)
>  {
>  	return zone->spanned_pages == 0;
>  }
> @@ -1273,7 +1273,7 @@ static inline bool folio_is_zone_movable(const struct folio *folio)
>   * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty
>   * intersection with the given zone
>   */
> -static inline bool zone_intersects(struct zone *zone,
> +static inline bool zone_intersects(const struct zone *const zone,
>  		unsigned long start_pfn, unsigned long nr_pages)
>  {
>  	if (zone_is_empty(zone))
> @@ -1581,12 +1581,12 @@ static inline int local_memory_node(int node_id) { return node_id; };
>  #define zone_idx(zone)		((zone) - (zone)->zone_pgdat->node_zones)
>
>  #ifdef CONFIG_ZONE_DEVICE
> -static inline bool zone_is_zone_device(struct zone *zone)
> +static inline bool zone_is_zone_device(const struct zone *const zone)
>  {
>  	return zone_idx(zone) == ZONE_DEVICE;
>  }
>  #else
> -static inline bool zone_is_zone_device(struct zone *zone)
> +static inline bool zone_is_zone_device(const struct zone *const zone)
>  {
>  	return false;
>  }
> @@ -1598,19 +1598,19 @@ static inline bool zone_is_zone_device(struct zone *zone)
>   * populated_zone(). If the whole zone is reserved then we can easily
>   * end up with populated_zone() && !managed_zone().
>   */
> -static inline bool managed_zone(struct zone *zone)
> +static inline bool managed_zone(const struct zone *const zone)
>  {
>  	return zone_managed_pages(zone);
>  }
>
>  /* Returns true if a zone has memory */
> -static inline bool populated_zone(struct zone *zone)
> +static inline bool populated_zone(const struct zone *const zone)
>  {
>  	return zone->present_pages;
>  }
>
>  #ifdef CONFIG_NUMA
> -static inline int zone_to_nid(struct zone *zone)
> +static inline int zone_to_nid(const struct zone *const zone)
>  {
>  	return zone->node;
>  }
> @@ -1620,7 +1620,7 @@ static inline void zone_set_nid(struct zone *zone, int nid)
>  	zone->node = nid;
>  }
>  #else
> -static inline int zone_to_nid(struct zone *zone)
> +static inline int zone_to_nid(const struct zone *zone)
>  {
>  	return 0;
>  }
> @@ -1647,7 +1647,7 @@ static inline int is_highmem_idx(enum zone_type idx)
>   * @zone: pointer to struct zone variable
>   * Return: 1 for a highmem zone, 0 otherwise
>   */
> -static inline int is_highmem(struct zone *zone)
> +static inline int is_highmem(const struct zone *const zone)
>  {
>  	return is_highmem_idx(zone_idx(zone));
>  }
> @@ -1713,12 +1713,12 @@ static inline struct zone *zonelist_zone(struct zoneref *zoneref)
>  	return zoneref->zone;
>  }
>
> -static inline int zonelist_zone_idx(struct zoneref *zoneref)
> +static inline int zonelist_zone_idx(const struct zoneref *const zoneref)
>  {
>  	return zoneref->zone_idx;
>  }
>
> -static inline int zonelist_node_idx(struct zoneref *zoneref)
> +static inline int zonelist_node_idx(const struct zoneref *const zoneref)
>  {
>  	return zone_to_nid(zoneref->zone);
>  }
> @@ -2021,7 +2021,7 @@ static inline struct page *__section_mem_map_addr(struct mem_section *section)
>  	return (struct page *)map;
>  }
>
> -static inline int present_section(struct mem_section *section)
> +static inline int present_section(const struct mem_section *const section)
>  {
>  	return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
>  }
> @@ -2031,12 +2031,12 @@ static inline int present_section_nr(unsigned long nr)
>  	return present_section(__nr_to_section(nr));
>  }
>
> -static inline int valid_section(struct mem_section *section)
> +static inline int valid_section(const struct mem_section *const section)
>  {
>  	return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
>  }
>
> -static inline int early_section(struct mem_section *section)
> +static inline int early_section(const struct mem_section *const section)
>  {
>  	return (section && (section->section_mem_map & SECTION_IS_EARLY));
>  }
> @@ -2046,27 +2046,27 @@ static inline int valid_section_nr(unsigned long nr)
>  	return valid_section(__nr_to_section(nr));
>  }
>
> -static inline int online_section(struct mem_section *section)
> +static inline int online_section(const struct mem_section *const section)
>  {
>  	return (section && (section->section_mem_map & SECTION_IS_ONLINE));
>  }
>
>  #ifdef CONFIG_ZONE_DEVICE
> -static inline int online_device_section(struct mem_section *section)
> +static inline int online_device_section(const struct mem_section *const section)
>  {
>  	unsigned long flags = SECTION_IS_ONLINE | SECTION_TAINT_ZONE_DEVICE;
>
>  	return section && ((section->section_mem_map & flags) == flags);
>  }
>  #else
> -static inline int online_device_section(struct mem_section *section)
> +static inline int online_device_section(const struct mem_section *const section)
>  {
>  	return 0;
>  }
>  #endif
>
>  #ifdef CONFIG_SPARSEMEM_VMEMMAP_PREINIT
> -static inline int preinited_vmemmap_section(struct mem_section *section)
> +static inline int preinited_vmemmap_section(const struct mem_section *const section)
>  {
>  	return (section &&
>  		(section->section_mem_map & SECTION_IS_VMEMMAP_PREINIT));
> @@ -2076,7 +2076,7 @@ void sparse_vmemmap_init_nid_early(int nid);
>  void sparse_vmemmap_init_nid_late(int nid);
>
>  #else
> -static inline int preinited_vmemmap_section(struct mem_section *section)
> +static inline int preinited_vmemmap_section(const struct mem_section *const section)
>  {
>  	return 0;
>  }
> --
> 2.47.2
>
Re: [PATCH v5 03/12] mm: constify zone related test functions for improved const-correctness
Posted by David Hildenbrand 3 months, 1 week ago 
On 01.09.25 14:30, Max Kellermann wrote:
> We select certain test functions which either invoke each other,
> functions that are already const-ified, or no further functions.
> 
> It is therefore relatively trivial to const-ify them, which
> provides a basis for further const-ification further up the call
> stack.
> 
> Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
> ---

Also some getters hiding in between the test functions.

Acked-by: David Hildenbrand <david@redhat.com>

-- 
Cheers

David / dhildenb

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