From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
This patch implements workingset detection for anonymous LRU.
All the infrastructure is implemented by the previous patches so this patch
just activates the workingset detection by installing/retrieving
the shadow entry.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
---
include/linux/swap.h | 6 ++++++
mm/memory.c | 11 ++++-------
mm/swap_state.c | 23 ++++++++++++++++++-----
mm/vmscan.c | 7 ++++---
mm/workingset.c | 5 +++--
5 files changed, 35 insertions(+), 17 deletions(-)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 901da54..9ee78b8 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -416,6 +416,7 @@ extern struct address_space *swapper_spaces[];
extern unsigned long total_swapcache_pages(void);
extern void show_swap_cache_info(void);
extern int add_to_swap(struct page *page);
+extern void *get_shadow_from_swap_cache(swp_entry_t entry);
extern int add_to_swap_cache(struct page *page, swp_entry_t entry,
gfp_t gfp, void **shadowp);
extern void __delete_from_swap_cache(struct page *page,
@@ -575,6 +576,11 @@ static inline int add_to_swap(struct page *page)
return 0;
}
+static inline void *get_shadow_from_swap_cache(swp_entry_t entry)
+{
+ return NULL;
+}
+
static inline int add_to_swap_cache(struct page *page, swp_entry_t entry,
gfp_t gfp_mask, void **shadowp)
{
diff --git a/mm/memory.c b/mm/memory.c
index f221f96..2411cf57 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3094,6 +3094,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
int locked;
int exclusive = 0;
vm_fault_t ret = 0;
+ void *shadow = NULL;
if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte))
goto out;
@@ -3143,13 +3144,9 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
if (err)
goto out_page;
- /*
- * XXX: Move to lru_cache_add() when it
- * supports new vs putback
- */
- spin_lock_irq(&page_pgdat(page)->lru_lock);
- lru_note_cost_page(page);
- spin_unlock_irq(&page_pgdat(page)->lru_lock);
+ shadow = get_shadow_from_swap_cache(entry);
+ if (shadow)
+ workingset_refault(page, shadow);
lru_cache_add(page);
swap_readpage(page, true);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 43c4e3a..90c5bd1 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -106,6 +106,20 @@ void show_swap_cache_info(void)
printk("Total swap = %lukB\n", total_swap_pages << (PAGE_SHIFT - 10));
}
+void *get_shadow_from_swap_cache(swp_entry_t entry)
+{
+ struct address_space *address_space = swap_address_space(entry);
+ pgoff_t idx = swp_offset(entry);
+ struct page *page;
+
+ page = find_get_entry(address_space, idx);
+ if (xa_is_value(page))
+ return page;
+ if (page)
+ put_page(page);
+ return NULL;
+}
+
/*
* add_to_swap_cache resembles add_to_page_cache_locked on swapper_space,
* but sets SwapCache flag and private instead of mapping and index.
@@ -405,6 +419,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
{
struct swap_info_struct *si;
struct page *page;
+ void *shadow = NULL;
*new_page_allocated = false;
@@ -473,7 +488,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
__SetPageSwapBacked(page);
/* May fail (-ENOMEM) if XArray node allocation failed. */
- if (add_to_swap_cache(page, entry, gfp_mask & GFP_KERNEL, NULL)) {
+ if (add_to_swap_cache(page, entry, gfp_mask & GFP_KERNEL, &shadow)) {
put_swap_page(page, entry);
goto fail_unlock;
}
@@ -483,10 +498,8 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
goto fail_unlock;
}
- /* XXX: Move to lru_cache_add() when it supports new vs putback */
- spin_lock_irq(&page_pgdat(page)->lru_lock);
- lru_note_cost_page(page);
- spin_unlock_irq(&page_pgdat(page)->lru_lock);
+ if (shadow)
+ workingset_refault(page, shadow);
/* Caller will initiate read into locked page */
SetPageWorkingset(page);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 37943bf..eb02d18 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -859,6 +859,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
{
unsigned long flags;
int refcount;
+ void *shadow = NULL;
BUG_ON(!PageLocked(page));
BUG_ON(mapping != page_mapping(page));
@@ -901,13 +902,13 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
if (PageSwapCache(page)) {
swp_entry_t swap = { .val = page_private(page) };
mem_cgroup_swapout(page, swap);
- __delete_from_swap_cache(page, swap, NULL);
+ if (reclaimed && !mapping_exiting(mapping))
+ shadow = workingset_eviction(page, target_memcg);
+ __delete_from_swap_cache(page, swap, shadow);
xa_unlock_irqrestore(&mapping->i_pages, flags);
put_swap_page(page, swap);
- workingset_eviction(page, target_memcg);
} else {
void (*freepage)(struct page *);
- void *shadow = NULL;
freepage = mapping->a_ops->freepage;
/*
diff --git a/mm/workingset.c b/mm/workingset.c
index 8395e60..3769ae6 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -353,8 +353,9 @@ void workingset_refault(struct page *page, void *shadow)
/*
* Compare the distance to the existing workingset size. We
* don't activate pages that couldn't stay resident even if
- * all the memory was available to the page cache. Whether
- * cache can compete with anon or not depends on having swap.
+ * all the memory was available to the workingset. Whether
+ * workingset competetion need to consider anon or not depends
+ * on having swap.
*/
workingset_size = lruvec_page_state(eviction_lruvec, NR_ACTIVE_FILE);
if (mem_cgroup_get_nr_swap_pages(memcg) > 0) {
--
2.7.4
