diff mbox series

[v2,2/4] mm: migrate: move the numamigrate_isolate_page() into do_numa_page()

Message ID 9ff2a9e3e644103a08b9b84b76b39bbd4c60020b.1692665449.git.baolin.wang@linux.alibaba.com (mailing list archive)
State New
Headers show
Series Extend migrate_misplaced_page() to support batch migration | expand

Commit Message

Baolin Wang Aug. 22, 2023, 12:53 a.m. UTC 
Move the numamigrate_isolate_page() into do_numa_page() to simplify the
migrate_misplaced_page(), which now only focuses on page migration, and
it also serves as a preparation for supporting batch migration for
migrate_misplaced_page().

While we are at it, change the numamigrate_isolate_page() to boolean
type to make the return value more clear.

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
---
 include/linux/migrate.h |  6 ++++++
 mm/huge_memory.c        |  7 +++++++
 mm/memory.c             |  7 +++++++
 mm/migrate.c            | 22 +++++++---------------
 4 files changed, 27 insertions(+), 15 deletions(-)

Comments

Bharata B Rao Aug. 22, 2023, 9:02 a.m. UTC | #1 
On 22-Aug-23 6:23 AM, Baolin Wang wrote:
> Move the numamigrate_isolate_page() into do_numa_page() to simplify the
> migrate_misplaced_page(), which now only focuses on page migration, and
> it also serves as a preparation for supporting batch migration for
> migrate_misplaced_page().
> 
> While we are at it, change the numamigrate_isolate_page() to boolean
> type to make the return value more clear.
> 
> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
> ---
>  include/linux/migrate.h |  6 ++++++
>  mm/huge_memory.c        |  7 +++++++
>  mm/memory.c             |  7 +++++++
>  mm/migrate.c            | 22 +++++++---------------
>  4 files changed, 27 insertions(+), 15 deletions(-)
> 
> diff --git a/include/linux/migrate.h b/include/linux/migrate.h
> index 711dd9412561..ddcd62ec2c12 100644
> --- a/include/linux/migrate.h
> +++ b/include/linux/migrate.h
> @@ -144,12 +144,18 @@ const struct movable_operations *page_movable_ops(struct page *page)
>  #ifdef CONFIG_NUMA_BALANCING
>  int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
>  			   int node);
> +bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page);
>  #else
>  static inline int migrate_misplaced_page(struct page *page,
>  					 struct vm_area_struct *vma, int node)
>  {
>  	return -EAGAIN; /* can't migrate now */
>  }
> +
> +static inline bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
> +{
> +	return false;
> +}
>  #endif /* CONFIG_NUMA_BALANCING */
>  
>  #ifdef CONFIG_MIGRATION
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 4a9b34a89854..07149ead11e4 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -1496,6 +1496,7 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
>  	int target_nid, last_cpupid = (-1 & LAST_CPUPID_MASK);
>  	bool migrated = false, writable = false;
>  	int flags = 0;
> +	pg_data_t *pgdat;
>  
>  	vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd);
>  	if (unlikely(!pmd_same(oldpmd, *vmf->pmd))) {
> @@ -1545,6 +1546,12 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
>  		goto migrate_fail;
>  	}
>  
> +	pgdat = NODE_DATA(target_nid);
> +	if (!numamigrate_isolate_page(pgdat, page)) {
> +		put_page(page);
> +		goto migrate_fail;
> +	}
> +
>  	migrated = migrate_misplaced_page(page, vma, target_nid);
>  	if (migrated) {
>  		flags |= TNF_MIGRATED;
> diff --git a/mm/memory.c b/mm/memory.c
> index fc6f6b7a70e1..4e451b041488 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -4769,6 +4769,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf)
>  	int target_nid;
>  	pte_t pte, old_pte;
>  	int flags = 0;
> +	pg_data_t *pgdat;
>  
>  	/*
>  	 * The "pte" at this point cannot be used safely without
> @@ -4844,6 +4845,12 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf)
>  		goto migrate_fail;
>  	}
>  
> +	pgdat = NODE_DATA(target_nid);
> +	if (!numamigrate_isolate_page(pgdat, page)) {
> +		put_page(page);
> +		goto migrate_fail;
> +	}
> +
>  	/* Migrate to the requested node */
>  	if (migrate_misplaced_page(page, vma, target_nid)) {
>  		page_nid = target_nid;
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 9cc98fb1d6ec..0b2b69a2a7ab 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -2478,7 +2478,7 @@ static struct folio *alloc_misplaced_dst_folio(struct folio *src,
>  	return __folio_alloc_node(gfp, order, nid);
>  }
>  
> -static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
> +bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
>  {
>  	int nr_pages = thp_nr_pages(page);
>  	int order = compound_order(page);
> @@ -2496,11 +2496,11 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
>  				break;
>  		}

There is an other s/return 0/return false/ changed required here for this chunk:

if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING))
                        return 0;

>  		wakeup_kswapd(pgdat->node_zones + z, 0, order, ZONE_MOVABLE);
> -		return 0;
> +		return false;
>  	}

Looks like this whole section under "Avoiding migrating to a node that is nearly full"
check could be moved to numa_page_can_migrate() as that can be considered as one more
check (or action to) see if the page can be migrated or not. After that numamigrate_isolate_page()
will truly be about isolating the page.

Regards,
Bharata.
Baolin Wang Aug. 24, 2023, 3:14 a.m. UTC | #2 
On 8/22/2023 5:02 PM, Bharata B Rao wrote:
> On 22-Aug-23 6:23 AM, Baolin Wang wrote:
>> Move the numamigrate_isolate_page() into do_numa_page() to simplify the
>> migrate_misplaced_page(), which now only focuses on page migration, and
>> it also serves as a preparation for supporting batch migration for
>> migrate_misplaced_page().
>>
>> While we are at it, change the numamigrate_isolate_page() to boolean
>> type to make the return value more clear.
>>
>> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
>> ---
>>   include/linux/migrate.h |  6 ++++++
>>   mm/huge_memory.c        |  7 +++++++
>>   mm/memory.c             |  7 +++++++
>>   mm/migrate.c            | 22 +++++++---------------
>>   4 files changed, 27 insertions(+), 15 deletions(-)
>>
>> diff --git a/include/linux/migrate.h b/include/linux/migrate.h
>> index 711dd9412561..ddcd62ec2c12 100644
>> --- a/include/linux/migrate.h
>> +++ b/include/linux/migrate.h
>> @@ -144,12 +144,18 @@ const struct movable_operations *page_movable_ops(struct page *page)
>>   #ifdef CONFIG_NUMA_BALANCING
>>   int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
>>   			   int node);
>> +bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page);
>>   #else
>>   static inline int migrate_misplaced_page(struct page *page,
>>   					 struct vm_area_struct *vma, int node)
>>   {
>>   	return -EAGAIN; /* can't migrate now */
>>   }
>> +
>> +static inline bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
>> +{
>> +	return false;
>> +}
>>   #endif /* CONFIG_NUMA_BALANCING */
>>   
>>   #ifdef CONFIG_MIGRATION
>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>> index 4a9b34a89854..07149ead11e4 100644
>> --- a/mm/huge_memory.c
>> +++ b/mm/huge_memory.c
>> @@ -1496,6 +1496,7 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
>>   	int target_nid, last_cpupid = (-1 & LAST_CPUPID_MASK);
>>   	bool migrated = false, writable = false;
>>   	int flags = 0;
>> +	pg_data_t *pgdat;
>>   
>>   	vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd);
>>   	if (unlikely(!pmd_same(oldpmd, *vmf->pmd))) {
>> @@ -1545,6 +1546,12 @@ vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
>>   		goto migrate_fail;
>>   	}
>>   
>> +	pgdat = NODE_DATA(target_nid);
>> +	if (!numamigrate_isolate_page(pgdat, page)) {
>> +		put_page(page);
>> +		goto migrate_fail;
>> +	}
>> +
>>   	migrated = migrate_misplaced_page(page, vma, target_nid);
>>   	if (migrated) {
>>   		flags |= TNF_MIGRATED;
>> diff --git a/mm/memory.c b/mm/memory.c
>> index fc6f6b7a70e1..4e451b041488 100644
>> --- a/mm/memory.c
>> +++ b/mm/memory.c
>> @@ -4769,6 +4769,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf)
>>   	int target_nid;
>>   	pte_t pte, old_pte;
>>   	int flags = 0;
>> +	pg_data_t *pgdat;
>>   
>>   	/*
>>   	 * The "pte" at this point cannot be used safely without
>> @@ -4844,6 +4845,12 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf)
>>   		goto migrate_fail;
>>   	}
>>   
>> +	pgdat = NODE_DATA(target_nid);
>> +	if (!numamigrate_isolate_page(pgdat, page)) {
>> +		put_page(page);
>> +		goto migrate_fail;
>> +	}
>> +
>>   	/* Migrate to the requested node */
>>   	if (migrate_misplaced_page(page, vma, target_nid)) {
>>   		page_nid = target_nid;
>> diff --git a/mm/migrate.c b/mm/migrate.c
>> index 9cc98fb1d6ec..0b2b69a2a7ab 100644
>> --- a/mm/migrate.c
>> +++ b/mm/migrate.c
>> @@ -2478,7 +2478,7 @@ static struct folio *alloc_misplaced_dst_folio(struct folio *src,
>>   	return __folio_alloc_node(gfp, order, nid);
>>   }
>>   
>> -static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
>> +bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
>>   {
>>   	int nr_pages = thp_nr_pages(page);
>>   	int order = compound_order(page);
>> @@ -2496,11 +2496,11 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
>>   				break;
>>   		}
> 
> There is an other s/return 0/return false/ changed required here for this chunk:
> 
> if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING))
>                          return 0;

Good catch.

> 
>>   		wakeup_kswapd(pgdat->node_zones + z, 0, order, ZONE_MOVABLE);
>> -		return 0;
>> +		return false;
>>   	}
> 
> Looks like this whole section under "Avoiding migrating to a node that is nearly full"
> check could be moved to numa_page_can_migrate() as that can be considered as one more
> check (or action to) see if the page can be migrated or not. After that numamigrate_isolate_page()
> will truly be about isolating the page.

Good idea. Will do. Thanks.
diff mbox series

Patch

diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 711dd9412561..ddcd62ec2c12 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -144,12 +144,18 @@  const struct movable_operations *page_movable_ops(struct page *page)
 #ifdef CONFIG_NUMA_BALANCING
 int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
 			   int node);
+bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page);
 #else
 static inline int migrate_misplaced_page(struct page *page,
 					 struct vm_area_struct *vma, int node)
 {
 	return -EAGAIN; /* can't migrate now */
 }
+
+static inline bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
+{
+	return false;
+}
 #endif /* CONFIG_NUMA_BALANCING */
 
 #ifdef CONFIG_MIGRATION
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 4a9b34a89854..07149ead11e4 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1496,6 +1496,7 @@  vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
 	int target_nid, last_cpupid = (-1 & LAST_CPUPID_MASK);
 	bool migrated = false, writable = false;
 	int flags = 0;
+	pg_data_t *pgdat;
 
 	vmf->ptl = pmd_lock(vma->vm_mm, vmf->pmd);
 	if (unlikely(!pmd_same(oldpmd, *vmf->pmd))) {
@@ -1545,6 +1546,12 @@  vm_fault_t do_huge_pmd_numa_page(struct vm_fault *vmf)
 		goto migrate_fail;
 	}
 
+	pgdat = NODE_DATA(target_nid);
+	if (!numamigrate_isolate_page(pgdat, page)) {
+		put_page(page);
+		goto migrate_fail;
+	}
+
 	migrated = migrate_misplaced_page(page, vma, target_nid);
 	if (migrated) {
 		flags |= TNF_MIGRATED;
diff --git a/mm/memory.c b/mm/memory.c
index fc6f6b7a70e1..4e451b041488 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4769,6 +4769,7 @@  static vm_fault_t do_numa_page(struct vm_fault *vmf)
 	int target_nid;
 	pte_t pte, old_pte;
 	int flags = 0;
+	pg_data_t *pgdat;
 
 	/*
 	 * The "pte" at this point cannot be used safely without
@@ -4844,6 +4845,12 @@  static vm_fault_t do_numa_page(struct vm_fault *vmf)
 		goto migrate_fail;
 	}
 
+	pgdat = NODE_DATA(target_nid);
+	if (!numamigrate_isolate_page(pgdat, page)) {
+		put_page(page);
+		goto migrate_fail;
+	}
+
 	/* Migrate to the requested node */
 	if (migrate_misplaced_page(page, vma, target_nid)) {
 		page_nid = target_nid;
diff --git a/mm/migrate.c b/mm/migrate.c
index 9cc98fb1d6ec..0b2b69a2a7ab 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2478,7 +2478,7 @@  static struct folio *alloc_misplaced_dst_folio(struct folio *src,
 	return __folio_alloc_node(gfp, order, nid);
 }
 
-static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
+bool numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 {
 	int nr_pages = thp_nr_pages(page);
 	int order = compound_order(page);
@@ -2496,11 +2496,11 @@  static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 				break;
 		}
 		wakeup_kswapd(pgdat->node_zones + z, 0, order, ZONE_MOVABLE);
-		return 0;
+		return false;
 	}
 
 	if (!isolate_lru_page(page))
-		return 0;
+		return false;
 
 	mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_is_file_lru(page),
 			    nr_pages);
@@ -2511,7 +2511,7 @@  static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 	 * disappearing underneath us during migration.
 	 */
 	put_page(page);
-	return 1;
+	return true;
 }
 
 /*
@@ -2523,16 +2523,12 @@  int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
 			   int node)
 {
 	pg_data_t *pgdat = NODE_DATA(node);
-	int isolated;
+	int migrated = 1;
 	int nr_remaining;
 	unsigned int nr_succeeded;
 	LIST_HEAD(migratepages);
 	int nr_pages = thp_nr_pages(page);
 
-	isolated = numamigrate_isolate_page(pgdat, page);
-	if (!isolated)
-		goto out;
-
 	list_add(&page->lru, &migratepages);
 	nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_folio,
 				     NULL, node, MIGRATE_ASYNC,
@@ -2544,7 +2540,7 @@  int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
 					page_is_file_lru(page), -nr_pages);
 			putback_lru_page(page);
 		}
-		isolated = 0;
+		migrated = 0;
 	}
 	if (nr_succeeded) {
 		count_vm_numa_events(NUMA_PAGE_MIGRATE, nr_succeeded);
@@ -2553,11 +2549,7 @@  int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma,
 					    nr_succeeded);
 	}
 	BUG_ON(!list_empty(&migratepages));
-	return isolated;
-
-out:
-	put_page(page);
-	return 0;
+	return migrated;
 }
 #endif /* CONFIG_NUMA_BALANCING */
 #endif /* CONFIG_NUMA */