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mm: vm_total_pages and build_all_zonelists() cleanup

PATCH Applied David Hildenbrand 5 participants 12 messages Jun 19, 2020 – Jun 23, 2020

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#0 lore raw

cover mm: vm_total_pages and build_all_zonelists() cleanup

Let's drop vm_total_pages and inline nr_free_pagecache_pages() into build_all_zonelists().

David Hildenbrand (2):
mm: drop vm_total_pages
mm/page_alloc: drop nr_free_pagecache_pages()

 include/linux/swap.h |  2 --
 mm/memory_hotplug.c  |  3 ---
 mm/page-writeback.c  |  6 ++----
 mm/page_alloc.c      | 18 ++++--------------
 mm/vmscan.c          |  5 -----
 5 files changed, 6 insertions(+), 28 deletions(-)
Signature · 1 line
2.26.2
#1 lore raw

PATCH 1/2 mm: drop vm_total_pages

The global variable "vm_total_pages" is a relict from older days. There is only a single user that reads the variable - build_all_zonelists() - and the first thing it does is updating it. Use a local variable in build_all_zonelists() instead and drop the local variable.

Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Huang Ying <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Wei Yang <[email protected]>
---
 include/linux/swap.h | 1 -
 mm/memory_hotplug.c  | 3 ---
 mm/page-writeback.c  | 6 ++----
 mm/page_alloc.c      | 2 ++
 mm/vmscan.c          | 5 -----
 5 files changed, 4 insertions(+), 13 deletions(-)
include/linux/swap.h +0 -1
index 4c5974bb9ba94..124261acd5d0a 100644
@@ -371,7 +371,6 @@ extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
-extern unsigned long vm_total_pages;
 
 extern unsigned long reclaim_pages(struct list_head *page_list);
 #ifdef CONFIG_NUMA
mm/memory_hotplug.c +0 -3
index 9b34e03e730a4..d682781cce48d 100644
@@ -835,8 +835,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
 	kswapd_run(nid);
 	kcompactd_run(nid);
 
-	vm_total_pages = nr_free_pagecache_pages();
-
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_ONLINE, &arg);
@@ -1586,7 +1584,6 @@ static int __ref __offline_pages(unsigned long start_pfn,
 		kcompactd_stop(node);
 	}
 
-	vm_total_pages = nr_free_pagecache_pages();
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_OFFLINE, &arg);
mm/page-writeback.c +2 -4
index 28b3e7a675657..4e4ddd67b71e5 100644
@@ -2076,13 +2076,11 @@ static int page_writeback_cpu_online(unsigned int cpu)
  * Called early on to tune the page writeback dirty limits.
  *
  * We used to scale dirty pages according to how total memory
- * related to pages that could be allocated for buffers (by
- * comparing nr_free_buffer_pages() to vm_total_pages.
+ * related to pages that could be allocated for buffers.
  *
  * However, that was when we used "dirty_ratio" to scale with
  * all memory, and we don't do that any more. "dirty_ratio"
- * is now applied to total non-HIGHPAGE memory (by subtracting
- * totalhigh_pages from vm_total_pages), and as such we can't
+ * is now applied to total non-HIGHPAGE memory, and as such we can't
  * get into the old insane situation any more where we had
  * large amounts of dirty pages compared to a small amount of
  * non-HIGHMEM memory.
mm/page_alloc.c +2 -0
index 0c435b2ed665c..7b0dde69748c1 100644
@@ -5903,6 +5903,8 @@ build_all_zonelists_init(void)
  */
 void __ref build_all_zonelists(pg_data_t *pgdat)
 {
+	unsigned long vm_total_pages;
+
 	if (system_state == SYSTEM_BOOTING) {
 		build_all_zonelists_init();
 	} else {
mm/vmscan.c +0 -5
index b6d84326bdf2d..0010859747df2 100644
@@ -170,11 +170,6 @@ struct scan_control {
  * From 0 .. 200.  Higher means more swappy.
  */
 int vm_swappiness = 60;
-/*
- * The total number of pages which are beyond the high watermark within all
- * zones.
- */
-unsigned long vm_total_pages;
 
 static void set_task_reclaim_state(struct task_struct *task,
 				   struct reclaim_state *rs)
Signature · 1 line
2.26.2
Reviewed-by on v1 1/2
#2 lore raw

Re: [PATCH v1 1/2] mm: drop vm_total_pages

Quoted 5 lines · David Hildenbrand

The global variable "vm_total_pages" is a relict from older days. There is only a single user that reads the variable - build_all_zonelists() - and the first thing it does is updating it. Use a local variable in build_all_zonelists() instead and drop the local variable.

Quoted 7 lines
Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Huang Ying <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Wei Yang <[email protected]>
Quoted 92 lines

---

include/linux/swap.h | 1 -
mm/memory_hotplug.c  | 3 ---
mm/page-writeback.c  | 6 ++----
mm/page_alloc.c      | 2 ++
mm/vmscan.c          | 5 -----
5 files changed, 4 insertions(+), 13 deletions(-)
include/linux/swap.h +0 -1
index 4c5974bb9ba94..124261acd5d0a 100644
@@ -371,7 +371,6 @@ extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
-extern unsigned long vm_total_pages;
 
 extern unsigned long reclaim_pages(struct list_head *page_list);
 #ifdef CONFIG_NUMA
mm/memory_hotplug.c +0 -3
index 9b34e03e730a4..d682781cce48d 100644
@@ -835,8 +835,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
 	kswapd_run(nid);
 	kcompactd_run(nid);
 
-	vm_total_pages = nr_free_pagecache_pages();
-
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_ONLINE, &arg);
@@ -1586,7 +1584,6 @@ static int __ref __offline_pages(unsigned long start_pfn,
 		kcompactd_stop(node);
 	}
 
-	vm_total_pages = nr_free_pagecache_pages();
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_OFFLINE, &arg);
mm/page-writeback.c +2 -4
index 28b3e7a675657..4e4ddd67b71e5 100644
@@ -2076,13 +2076,11 @@ static int page_writeback_cpu_online(unsigned int cpu)
 * Called early on to tune the page writeback dirty limits.
 *
 * We used to scale dirty pages according to how total memory
- * related to pages that could be allocated for buffers (by
- * comparing nr_free_buffer_pages() to vm_total_pages.
+ * related to pages that could be allocated for buffers.
 *
 * However, that was when we used "dirty_ratio" to scale with
 * all memory, and we don't do that any more. "dirty_ratio"
- * is now applied to total non-HIGHPAGE memory (by subtracting
- * totalhigh_pages from vm_total_pages), and as such we can't
+ * is now applied to total non-HIGHPAGE memory, and as such we can't
 * get into the old insane situation any more where we had
 * large amounts of dirty pages compared to a small amount of
 * non-HIGHMEM memory.
mm/page_alloc.c +2 -0
index 0c435b2ed665c..7b0dde69748c1 100644
@@ -5903,6 +5903,8 @@ build_all_zonelists_init(void)
 */
 void __ref build_all_zonelists(pg_data_t *pgdat)
 {
+	unsigned long vm_total_pages;
+
 	if (system_state == SYSTEM_BOOTING) {
 		build_all_zonelists_init();
 	} else {
mm/vmscan.c +0 -5
index b6d84326bdf2d..0010859747df2 100644
@@ -170,11 +170,6 @@ struct scan_control {
 * From 0 .. 200.  Higher means more swappy.
 */
 int vm_swappiness = 60;
-/*
- * The total number of pages which are beyond the high watermark within all
- * zones.
- */
-unsigned long vm_total_pages;
 
 static void set_task_reclaim_state(struct task_struct *task,
 				   struct reclaim_state *rs)
Signature · 1 line
2.26.2
Signature · 2 lines
Wei Yang
Help you, Help me
Reviewed-by on v1 1/2
#3 lore raw

Re: [PATCH v1 1/2] mm: drop vm_total_pages

In reply to David Hildenbrand
Quoted 4 lines · David Hildenbrand

The global variable "vm_total_pages" is a relict from older days. There is only a single user that reads the variable - build_all_zonelists() - and the first thing it does is updating it. Use a local variable in build_all_zonelists() instead and drop the local variable.

Nit: ^ global

Quoted 7 lines
Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Huang Ying <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Wei Yang <[email protected]>

Except the nit above

Quoted 94 lines
---
 include/linux/swap.h | 1 -
 mm/memory_hotplug.c  | 3 ---
 mm/page-writeback.c  | 6 ++----
 mm/page_alloc.c      | 2 ++
 mm/vmscan.c          | 5 -----
 5 files changed, 4 insertions(+), 13 deletions(-)
include/linux/swap.h +0 -1
index 4c5974bb9ba94..124261acd5d0a 100644
@@ -371,7 +371,6 @@ extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
-extern unsigned long vm_total_pages;
 
 extern unsigned long reclaim_pages(struct list_head *page_list);
 #ifdef CONFIG_NUMA
mm/memory_hotplug.c +0 -3
index 9b34e03e730a4..d682781cce48d 100644
@@ -835,8 +835,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
 	kswapd_run(nid);
 	kcompactd_run(nid);
 
-	vm_total_pages = nr_free_pagecache_pages();
-
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_ONLINE, &arg);
@@ -1586,7 +1584,6 @@ static int __ref __offline_pages(unsigned long start_pfn,
 		kcompactd_stop(node);
 	}
 
-	vm_total_pages = nr_free_pagecache_pages();
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_OFFLINE, &arg);
mm/page-writeback.c +2 -4
index 28b3e7a675657..4e4ddd67b71e5 100644
@@ -2076,13 +2076,11 @@ static int page_writeback_cpu_online(unsigned int cpu)
  * Called early on to tune the page writeback dirty limits.
  *
  * We used to scale dirty pages according to how total memory
- * related to pages that could be allocated for buffers (by
- * comparing nr_free_buffer_pages() to vm_total_pages.
+ * related to pages that could be allocated for buffers.
  *
  * However, that was when we used "dirty_ratio" to scale with
  * all memory, and we don't do that any more. "dirty_ratio"
- * is now applied to total non-HIGHPAGE memory (by subtracting
- * totalhigh_pages from vm_total_pages), and as such we can't
+ * is now applied to total non-HIGHPAGE memory, and as such we can't
  * get into the old insane situation any more where we had
  * large amounts of dirty pages compared to a small amount of
  * non-HIGHMEM memory.
mm/page_alloc.c +2 -0
index 0c435b2ed665c..7b0dde69748c1 100644
@@ -5903,6 +5903,8 @@ build_all_zonelists_init(void)
  */
 void __ref build_all_zonelists(pg_data_t *pgdat)
 {
+	unsigned long vm_total_pages;
+
 	if (system_state == SYSTEM_BOOTING) {
 		build_all_zonelists_init();
 	} else {
mm/vmscan.c +0 -5
index b6d84326bdf2d..0010859747df2 100644
@@ -170,11 +170,6 @@ struct scan_control {
  * From 0 .. 200.  Higher means more swappy.
  */
 int vm_swappiness = 60;
-/*
- * The total number of pages which are beyond the high watermark within all
- * zones.
- */
-unsigned long vm_total_pages;
 
 static void set_task_reclaim_state(struct task_struct *task,
 				   struct reclaim_state *rs)
Signature · 1 line
2.26.2
Signature · 2 lines
Sincerely yours,
Mike.
#4 lore raw

Re: [PATCH v1 1/2] mm: drop vm_total_pages

Quoted 7 lines · Mike Rapoport
Quoted 4 lines · David Hildenbrand

The global variable "vm_total_pages" is a relict from older days. There is only a single user that reads the variable - build_all_zonelists() - and the first thing it does is updating it. Use a local variable in build_all_zonelists() instead and drop the local variable.

Nit: ^ global

Indeed, @Andrew, can you fix this up?

Thanks!

Signature · 3 lines
Thanks,

David / dhildenb
Reviewed-by on v1 1/2
#5 lore raw

Re: [PATCH v1 1/2] mm: drop vm_total_pages

In reply to David Hildenbrand
Quoted 92 lines

The global variable "vm_total_pages" is a relict from older days. There is only a single user that reads the variable - build_all_zonelists() - and the first thing it does is updating it. Use a local variable in build_all_zonelists() instead and drop the local variable.

Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Huang Ying <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Wei Yang <[email protected]>
---
 include/linux/swap.h | 1 -
 mm/memory_hotplug.c  | 3 ---
 mm/page-writeback.c  | 6 ++----
 mm/page_alloc.c      | 2 ++
 mm/vmscan.c          | 5 -----
 5 files changed, 4 insertions(+), 13 deletions(-)
include/linux/swap.h +0 -1
index 4c5974bb9ba94..124261acd5d0a 100644
@@ -371,7 +371,6 @@ extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
-extern unsigned long vm_total_pages;
 
 extern unsigned long reclaim_pages(struct list_head *page_list);
 #ifdef CONFIG_NUMA
mm/memory_hotplug.c +0 -3
index 9b34e03e730a4..d682781cce48d 100644
@@ -835,8 +835,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
        kswapd_run(nid);
        kcompactd_run(nid);
 
-       vm_total_pages = nr_free_pagecache_pages();
-
        writeback_set_ratelimit();
 
        memory_notify(MEM_ONLINE, &arg);
@@ -1586,7 +1584,6 @@ static int __ref __offline_pages(unsigned long start_pfn,
                kcompactd_stop(node);
        }
 
-       vm_total_pages = nr_free_pagecache_pages();
        writeback_set_ratelimit();
 
        memory_notify(MEM_OFFLINE, &arg);
mm/page-writeback.c +2 -4
index 28b3e7a675657..4e4ddd67b71e5 100644
@@ -2076,13 +2076,11 @@ static int page_writeback_cpu_online(unsigned int cpu)
  * Called early on to tune the page writeback dirty limits.
  *
  * We used to scale dirty pages according to how total memory
- * related to pages that could be allocated for buffers (by
- * comparing nr_free_buffer_pages() to vm_total_pages.
+ * related to pages that could be allocated for buffers.
  *
  * However, that was when we used "dirty_ratio" to scale with
  * all memory, and we don't do that any more. "dirty_ratio"
- * is now applied to total non-HIGHPAGE memory (by subtracting
- * totalhigh_pages from vm_total_pages), and as such we can't
+ * is now applied to total non-HIGHPAGE memory, and as such we can't
  * get into the old insane situation any more where we had
  * large amounts of dirty pages compared to a small amount of
  * non-HIGHMEM memory.
mm/page_alloc.c +2 -0
index 0c435b2ed665c..7b0dde69748c1 100644
@@ -5903,6 +5903,8 @@ build_all_zonelists_init(void)
  */
 void __ref build_all_zonelists(pg_data_t *pgdat)
 {
+       unsigned long vm_total_pages;
+
        if (system_state == SYSTEM_BOOTING) {
                build_all_zonelists_init();
        } else {
mm/vmscan.c +0 -0
index b6d84326bdf2d..0010859747df2 100644
@@ -170,11 +170,6 @@ struct scan_control {
  * From 0 .. 200.  Higher means more swappy.

mm/vmscan.c struct scan_control { · line 175

Quoted 10 lines
mm/vmscan.c +0 -5
  */
 int vm_swappiness = 60;
-/*
- * The total number of pages which are beyond the high watermark within all
- * zones.
- */
-unsigned long vm_total_pages;
 
 static void set_task_reclaim_state(struct task_struct *task,
                                   struct reclaim_state *rs)
reviewer Acked-by on v1 1/2
#6 lore raw

Re: [PATCH v1 1/2] mm: drop vm_total_pages

In reply to David Hildenbrand
Quoted 5 lines · David Hildenbrand

The global variable "vm_total_pages" is a relict from older days. There is only a single user that reads the variable - build_all_zonelists() - and the first thing it does is updating it. Use a local variable in build_all_zonelists() instead and drop the local variable.

Quoted 7 lines
Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Huang Ying <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Wei Yang <[email protected]>
Quoted 92 lines
---
 include/linux/swap.h | 1 -
 mm/memory_hotplug.c  | 3 ---
 mm/page-writeback.c  | 6 ++----
 mm/page_alloc.c      | 2 ++
 mm/vmscan.c          | 5 -----
 5 files changed, 4 insertions(+), 13 deletions(-)
include/linux/swap.h +0 -1
index 4c5974bb9ba94..124261acd5d0a 100644
@@ -371,7 +371,6 @@ extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem,
 extern unsigned long shrink_all_memory(unsigned long nr_pages);
 extern int vm_swappiness;
 extern int remove_mapping(struct address_space *mapping, struct page *page);
-extern unsigned long vm_total_pages;
 
 extern unsigned long reclaim_pages(struct list_head *page_list);
 #ifdef CONFIG_NUMA
mm/memory_hotplug.c +0 -3
index 9b34e03e730a4..d682781cce48d 100644
@@ -835,8 +835,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
 	kswapd_run(nid);
 	kcompactd_run(nid);
 
-	vm_total_pages = nr_free_pagecache_pages();
-
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_ONLINE, &arg);
@@ -1586,7 +1584,6 @@ static int __ref __offline_pages(unsigned long start_pfn,
 		kcompactd_stop(node);
 	}
 
-	vm_total_pages = nr_free_pagecache_pages();
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_OFFLINE, &arg);
mm/page-writeback.c +2 -4
index 28b3e7a675657..4e4ddd67b71e5 100644
@@ -2076,13 +2076,11 @@ static int page_writeback_cpu_online(unsigned int cpu)
  * Called early on to tune the page writeback dirty limits.
  *
  * We used to scale dirty pages according to how total memory
- * related to pages that could be allocated for buffers (by
- * comparing nr_free_buffer_pages() to vm_total_pages.
+ * related to pages that could be allocated for buffers.
  *
  * However, that was when we used "dirty_ratio" to scale with
  * all memory, and we don't do that any more. "dirty_ratio"
- * is now applied to total non-HIGHPAGE memory (by subtracting
- * totalhigh_pages from vm_total_pages), and as such we can't
+ * is now applied to total non-HIGHPAGE memory, and as such we can't
  * get into the old insane situation any more where we had
  * large amounts of dirty pages compared to a small amount of
  * non-HIGHMEM memory.
mm/page_alloc.c +2 -0
index 0c435b2ed665c..7b0dde69748c1 100644
@@ -5903,6 +5903,8 @@ build_all_zonelists_init(void)
  */
 void __ref build_all_zonelists(pg_data_t *pgdat)
 {
+	unsigned long vm_total_pages;
+
 	if (system_state == SYSTEM_BOOTING) {
 		build_all_zonelists_init();
 	} else {
mm/vmscan.c +0 -5
index b6d84326bdf2d..0010859747df2 100644
@@ -170,11 +170,6 @@ struct scan_control {
  * From 0 .. 200.  Higher means more swappy.
  */
 int vm_swappiness = 60;
-/*
- * The total number of pages which are beyond the high watermark within all
- * zones.
- */
-unsigned long vm_total_pages;
 
 static void set_task_reclaim_state(struct task_struct *task,
 				   struct reclaim_state *rs)
Signature · 1 line
2.26.2
Signature · 2 lines
Michal Hocko
SUSE Labs
#7 lore raw

PATCH 2/2 mm/page_alloc: drop nr_free_pagecache_pages()

In reply to David Hildenbrand

nr_free_pagecache_pages() isn't used outside page_alloc.c anymore - and the name does not really help to understand what's going on. Let's inline it instead and add a comment.

Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Huang Ying <[email protected]>
Cc Wei Yang <[email protected]>
---
 include/linux/swap.h |  1 -
 mm/page_alloc.c      | 16 ++--------------
 2 files changed, 2 insertions(+), 15 deletions(-)
include/linux/swap.h +0 -1
index 124261acd5d0a..9bde6c6b2c045 100644
@@ -327,7 +327,6 @@ void workingset_update_node(struct xa_node *node);
 /* linux/mm/page_alloc.c */
 extern unsigned long totalreserve_pages;
 extern unsigned long nr_free_buffer_pages(void);
-extern unsigned long nr_free_pagecache_pages(void);
 
 /* Definition of global_zone_page_state not available yet */
 #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
mm/page_alloc.c +2 -14
index 7b0dde69748c1..c38903d1b3b4d 100644
@@ -5177,19 +5177,6 @@ unsigned long nr_free_buffer_pages(void)
 }
 EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
 
-/**
- * nr_free_pagecache_pages - count number of pages beyond high watermark
- *
- * nr_free_pagecache_pages() counts the number of pages which are beyond the
- * high watermark within all zones.
- *
- * Return: number of pages beyond high watermark within all zones.
- */
-unsigned long nr_free_pagecache_pages(void)
-{
-	return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
-}
-
 static inline void show_node(struct zone *zone)
 {
 	if (IS_ENABLED(CONFIG_NUMA))
@@ -5911,7 +5898,8 @@ void __ref build_all_zonelists(pg_data_t *pgdat)
 		__build_all_zonelists(pgdat);
 		/* cpuset refresh routine should be here */
 	}
-	vm_total_pages = nr_free_pagecache_pages();
+	/* Get the number of free pages beyond high watermark in all zones. */
+	vm_total_pages = nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
 	/*
 	 * Disable grouping by mobility if the number of pages in the
 	 * system is too low to allow the mechanism to work. It would be
Signature · 1 line
2.26.2
Reviewed-by on v1 2/2
#8 lore raw

Re: [PATCH v1 2/2] mm/page_alloc: drop nr_free_pagecache_pages()

Quoted 3 lines · David Hildenbrand

nr_free_pagecache_pages() isn't used outside page_alloc.c anymore - and the name does not really help to understand what's going on. Let's inline it instead and add a comment.

Not sure "inline it" is the proper word for this.

Quoted 8 lines
Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Huang Ying <[email protected]>
Cc Wei Yang <[email protected]>

Besides:

Quoted 53 lines

---
include/linux/swap.h | 1 -
mm/page_alloc.c | 16 ++--------------

2 files changed, 2 insertions(+), 15 deletions(-)
include/linux/swap.h +0 -1
index 124261acd5d0a..9bde6c6b2c045 100644
@@ -327,7 +327,6 @@ void workingset_update_node(struct xa_node *node);
 /* linux/mm/page_alloc.c */
 extern unsigned long totalreserve_pages;
 extern unsigned long nr_free_buffer_pages(void);
-extern unsigned long nr_free_pagecache_pages(void);
 
 /* Definition of global_zone_page_state not available yet */
 #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
mm/page_alloc.c +2 -14
index 7b0dde69748c1..c38903d1b3b4d 100644
@@ -5177,19 +5177,6 @@ unsigned long nr_free_buffer_pages(void)
 }
 EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
 
-/**
- * nr_free_pagecache_pages - count number of pages beyond high watermark
- *
- * nr_free_pagecache_pages() counts the number of pages which are beyond the
- * high watermark within all zones.
- *
- * Return: number of pages beyond high watermark within all zones.
- */
-unsigned long nr_free_pagecache_pages(void)
-{
-	return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
-}
-
 static inline void show_node(struct zone *zone)
 {
 	if (IS_ENABLED(CONFIG_NUMA))
@@ -5911,7 +5898,8 @@ void __ref build_all_zonelists(pg_data_t *pgdat)
 		__build_all_zonelists(pgdat);
 		/* cpuset refresh routine should be here */
 	}
-	vm_total_pages = nr_free_pagecache_pages();
+	/* Get the number of free pages beyond high watermark in all zones. */
+	vm_total_pages = nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
 	/*
 	 * Disable grouping by mobility if the number of pages in the
 	 * system is too low to allow the mechanism to work. It would be
Signature · 1 line
2.26.2
Signature · 2 lines
Wei Yang
Help you, Help me
Reviewed-by on v1 2/2
#9 lore raw

Re: [PATCH v1 2/2] mm/page_alloc: drop nr_free_pagecache_pages()

In reply to David Hildenbrand
Quoted 11 lines · David Hildenbrand

nr_free_pagecache_pages() isn't used outside page_alloc.c anymore - and the name does not really help to understand what's going on. Let's inline it instead and add a comment.

Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Huang Ying <[email protected]>
Cc Wei Yang <[email protected]>
Quoted 55 lines
---
 include/linux/swap.h |  1 -
 mm/page_alloc.c      | 16 ++--------------
 2 files changed, 2 insertions(+), 15 deletions(-)
include/linux/swap.h +0 -1
index 124261acd5d0a..9bde6c6b2c045 100644
@@ -327,7 +327,6 @@ void workingset_update_node(struct xa_node *node);
 /* linux/mm/page_alloc.c */
 extern unsigned long totalreserve_pages;
 extern unsigned long nr_free_buffer_pages(void);
-extern unsigned long nr_free_pagecache_pages(void);
 
 /* Definition of global_zone_page_state not available yet */
 #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
mm/page_alloc.c +2 -14
index 7b0dde69748c1..c38903d1b3b4d 100644
@@ -5177,19 +5177,6 @@ unsigned long nr_free_buffer_pages(void)
 }
 EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
 
-/**
- * nr_free_pagecache_pages - count number of pages beyond high watermark
- *
- * nr_free_pagecache_pages() counts the number of pages which are beyond the
- * high watermark within all zones.
- *
- * Return: number of pages beyond high watermark within all zones.
- */
-unsigned long nr_free_pagecache_pages(void)
-{
-	return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
-}
-
 static inline void show_node(struct zone *zone)
 {
 	if (IS_ENABLED(CONFIG_NUMA))
@@ -5911,7 +5898,8 @@ void __ref build_all_zonelists(pg_data_t *pgdat)
 		__build_all_zonelists(pgdat);
 		/* cpuset refresh routine should be here */
 	}
-	vm_total_pages = nr_free_pagecache_pages();
+	/* Get the number of free pages beyond high watermark in all zones. */
+	vm_total_pages = nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
 	/*
 	 * Disable grouping by mobility if the number of pages in the
 	 * system is too low to allow the mechanism to work. It would be
Signature · 1 line
2.26.2
Signature · 2 lines
Sincerely yours,
Mike.
Reviewed-by on v1 2/2
#10 lore raw

Re: [PATCH v1 2/2] mm/page_alloc: drop nr_free_pagecache_pages()

In reply to David Hildenbrand
Quoted 53 lines

nr_free_pagecache_pages() isn't used outside page_alloc.c anymore - and the name does not really help to understand what's going on. Let's inline it instead and add a comment.

Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Huang Ying <[email protected]>
Cc Wei Yang <[email protected]>
---
 include/linux/swap.h |  1 -
 mm/page_alloc.c      | 16 ++--------------
 2 files changed, 2 insertions(+), 15 deletions(-)
include/linux/swap.h +0 -1
index 124261acd5d0a..9bde6c6b2c045 100644
@@ -327,7 +327,6 @@ void workingset_update_node(struct xa_node *node);
 /* linux/mm/page_alloc.c */
 extern unsigned long totalreserve_pages;
 extern unsigned long nr_free_buffer_pages(void);
-extern unsigned long nr_free_pagecache_pages(void);
 
 /* Definition of global_zone_page_state not available yet */
 #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
mm/page_alloc.c +0 -13
index 7b0dde69748c1..c38903d1b3b4d 100644
@@ -5177,19 +5177,6 @@ unsigned long nr_free_buffer_pages(void)
 }
 EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
 
-/**
- * nr_free_pagecache_pages - count number of pages beyond high watermark
- *
- * nr_free_pagecache_pages() counts the number of pages which are beyond the
- * high watermark within all zones.
- *
- * Return: number of pages beyond high watermark within all zones.
- */
-unsigned long nr_free_pagecache_pages(void)
-{
-       return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
-}
-
 static inline void show_node(struct zone *zone)
 {
        if (IS_ENABLED(CONFIG_NUMA))

mm/page_alloc.c void __ref build_all_zonelists(pg_data_t *pgdat) · line 5905

Quoted 9 lines
mm/page_alloc.c +2 -1
@@ -5911,7 +5898,8 @@ void __ref build_all_zonelists(pg_data_t *pgdat)
                __build_all_zonelists(pgdat);
                /* cpuset refresh routine should be here */
        }
-       vm_total_pages = nr_free_pagecache_pages();
+       /* Get the number of free pages beyond high watermark in all zones. */
+       vm_total_pages = nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
        /*
         * Disable grouping by mobility if the number of pages in the
         * system is too low to allow the mechanism to work. It would be
reviewer Acked-by on v1 2/2
#11 lore raw

Re: [PATCH v1 2/2] mm/page_alloc: drop nr_free_pagecache_pages()

In reply to David Hildenbrand
Quoted 11 lines · David Hildenbrand

nr_free_pagecache_pages() isn't used outside page_alloc.c anymore - and the name does not really help to understand what's going on. Let's inline it instead and add a comment.

Cc Andrew Morton <[email protected]>
Cc Johannes Weiner <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Minchan Kim <[email protected]>
Cc Huang Ying <[email protected]>
Cc Wei Yang <[email protected]>

nr_free_pagecache_pages was an awkward name which kind of makes sense but it is terribly confusing (e.g. there are pagecache consumers restricted to lowmem zones only).

Quoted 53 lines
---
 include/linux/swap.h |  1 -
 mm/page_alloc.c      | 16 ++--------------
 2 files changed, 2 insertions(+), 15 deletions(-)
include/linux/swap.h +0 -1
index 124261acd5d0a..9bde6c6b2c045 100644
@@ -327,7 +327,6 @@ void workingset_update_node(struct xa_node *node);
 /* linux/mm/page_alloc.c */
 extern unsigned long totalreserve_pages;
 extern unsigned long nr_free_buffer_pages(void);
-extern unsigned long nr_free_pagecache_pages(void);
 
 /* Definition of global_zone_page_state not available yet */
 #define nr_free_pages() global_zone_page_state(NR_FREE_PAGES)
mm/page_alloc.c +2 -14
index 7b0dde69748c1..c38903d1b3b4d 100644
@@ -5177,19 +5177,6 @@ unsigned long nr_free_buffer_pages(void)
 }
 EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
 
-/**
- * nr_free_pagecache_pages - count number of pages beyond high watermark
- *
- * nr_free_pagecache_pages() counts the number of pages which are beyond the
- * high watermark within all zones.
- *
- * Return: number of pages beyond high watermark within all zones.
- */
-unsigned long nr_free_pagecache_pages(void)
-{
-	return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
-}
-
 static inline void show_node(struct zone *zone)
 {
 	if (IS_ENABLED(CONFIG_NUMA))
@@ -5911,7 +5898,8 @@ void __ref build_all_zonelists(pg_data_t *pgdat)
 		__build_all_zonelists(pgdat);
 		/* cpuset refresh routine should be here */
 	}
-	vm_total_pages = nr_free_pagecache_pages();
+	/* Get the number of free pages beyond high watermark in all zones. */
+	vm_total_pages = nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
 	/*
 	 * Disable grouping by mobility if the number of pages in the
 	 * system is too low to allow the mechanism to work. It would be
Signature · 1 line
2.26.2
Signature · 2 lines
Michal Hocko
SUSE Labs