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(-)
--
2.26.2
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]>
Signed-off-by: David Hildenbrand <[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(-)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 4c5974bb9ba94..124261acd5d0a 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -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
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 9b34e03e730a4..d682781cce48d 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -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);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 28b3e7a675657..4e4ddd67b71e5 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -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.
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0c435b2ed665c..7b0dde69748c1 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -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 {
diff --git a/mm/vmscan.c b/mm/vmscan.c
index b6d84326bdf2d..0010859747df2 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -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)
--
2.26.2
On Fri, Jun 19, 2020 at 03:24:09PM +0200, David Hildenbrand wrote:
>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]>
>Signed-off-by: David Hildenbrand <[email protected]>
Reviewed-by: 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(-)
>
>diff --git a/include/linux/swap.h b/include/linux/swap.h
>index 4c5974bb9ba94..124261acd5d0a 100644
>--- a/include/linux/swap.h
>+++ b/include/linux/swap.h
>@@ -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
>diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
>index 9b34e03e730a4..d682781cce48d 100644
>--- a/mm/memory_hotplug.c
>+++ b/mm/memory_hotplug.c
>@@ -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);
>diff --git a/mm/page-writeback.c b/mm/page-writeback.c
>index 28b3e7a675657..4e4ddd67b71e5 100644
>--- a/mm/page-writeback.c
>+++ b/mm/page-writeback.c
>@@ -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.
>diff --git a/mm/page_alloc.c b/mm/page_alloc.c
>index 0c435b2ed665c..7b0dde69748c1 100644
>--- a/mm/page_alloc.c
>+++ b/mm/page_alloc.c
>@@ -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 {
>diff --git a/mm/vmscan.c b/mm/vmscan.c
>index b6d84326bdf2d..0010859747df2 100644
>--- a/mm/vmscan.c
>+++ b/mm/vmscan.c
>@@ -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)
>--
>2.26.2
--
Wei Yang
Help you, Help me
On Fri, Jun 19, 2020 at 03:24:09PM +0200, David Hildenbrand wrote:
> 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
> 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]>
> Signed-off-by: David Hildenbrand <[email protected]>
Except the nit above
Reviewed-by: Mike Rapoport <[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(-)
>
> diff --git a/include/linux/swap.h b/include/linux/swap.h
> index 4c5974bb9ba94..124261acd5d0a 100644
> --- a/include/linux/swap.h
> +++ b/include/linux/swap.h
> @@ -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
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index 9b34e03e730a4..d682781cce48d 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -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);
> diff --git a/mm/page-writeback.c b/mm/page-writeback.c
> index 28b3e7a675657..4e4ddd67b71e5 100644
> --- a/mm/page-writeback.c
> +++ b/mm/page-writeback.c
> @@ -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.
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 0c435b2ed665c..7b0dde69748c1 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -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 {
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index b6d84326bdf2d..0010859747df2 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -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)
> --
> 2.26.2
>
>
--
Sincerely yours,
Mike.
> 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]>
> Signed-off-by: David Hildenbrand <[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(-)
>
> diff --git a/include/linux/swap.h b/include/linux/swap.h
> index 4c5974bb9ba94..124261acd5d0a 100644
> --- a/include/linux/swap.h
> +++ b/include/linux/swap.h
> @@ -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
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index 9b34e03e730a4..d682781cce48d 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -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);
> diff --git a/mm/page-writeback.c b/mm/page-writeback.c
> index 28b3e7a675657..4e4ddd67b71e5 100644
> --- a/mm/page-writeback.c
> +++ b/mm/page-writeback.c
> @@ -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.
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 0c435b2ed665c..7b0dde69748c1 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -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 {
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index b6d84326bdf2d..0010859747df2 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -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)
Reviewed-by: Pankaj Gupta <[email protected]>
On 21.06.20 16:46, Mike Rapoport wrote:
> On Fri, Jun 19, 2020 at 03:24:09PM +0200, David Hildenbrand wrote:
>> 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!
--
Thanks,
David / dhildenb
On Fri 19-06-20 15:24:09, David Hildenbrand wrote:
> 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]>
> Signed-off-by: David Hildenbrand <[email protected]>
Acked-by: Michal Hocko <[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(-)
>
> diff --git a/include/linux/swap.h b/include/linux/swap.h
> index 4c5974bb9ba94..124261acd5d0a 100644
> --- a/include/linux/swap.h
> +++ b/include/linux/swap.h
> @@ -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
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index 9b34e03e730a4..d682781cce48d 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -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);
> diff --git a/mm/page-writeback.c b/mm/page-writeback.c
> index 28b3e7a675657..4e4ddd67b71e5 100644
> --- a/mm/page-writeback.c
> +++ b/mm/page-writeback.c
> @@ -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.
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index 0c435b2ed665c..7b0dde69748c1 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -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 {
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index b6d84326bdf2d..0010859747df2 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -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)
> --
> 2.26.2
--
Michal Hocko
SUSE Labs