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 | 7 ++++++-
mm/swap_state.c | 20 ++++++++++++++++++--
mm/vmscan.c | 7 +++++--
4 files changed, 35 insertions(+), 5 deletions(-)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 273de48..fb4772e 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -408,6 +408,7 @@ 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 int __add_to_swap_cache(struct page *page, swp_entry_t entry);
@@ -566,6 +567,11 @@ 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 5f7813a..91a2097 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2925,10 +2925,15 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma,
vmf->address);
if (page) {
+ void *shadow;
+
__SetPageLocked(page);
__SetPageSwapBacked(page);
set_page_private(page, entry.val);
- lru_cache_add_anon(page);
+ shadow = get_shadow_from_swap_cache(entry);
+ if (shadow)
+ workingset_refault(page, shadow);
+ lru_cache_add(page);
swap_readpage(page, true);
}
} else {
diff --git a/mm/swap_state.c b/mm/swap_state.c
index f06af84..f996455 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -107,6 +107,18 @@ 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;
+ 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.
@@ -376,6 +388,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
struct page *found_page = NULL, *new_page = NULL;
struct swap_info_struct *si;
int err;
+ void *shadow;
*new_page_allocated = false;
do {
@@ -431,12 +444,15 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
/* May fail (-ENOMEM) if XArray node allocation failed. */
__SetPageLocked(new_page);
__SetPageSwapBacked(new_page);
+ shadow = NULL;
err = add_to_swap_cache(new_page, entry,
- gfp_mask & GFP_KERNEL, NULL);
+ gfp_mask & GFP_KERNEL, &shadow);
if (likely(!err)) {
/* Initiate read into locked page */
SetPageWorkingset(new_page);
- lru_cache_add_anon(new_page);
+ if (shadow)
+ workingset_refault(new_page, shadow);
+ lru_cache_add(new_page);
*new_page_allocated = true;
return new_page;
}
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 9871861..b37cc26 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -867,6 +867,7 @@ 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));
@@ -909,12 +910,13 @@ 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);
} else {
void (*freepage)(struct page *);
- void *shadow = NULL;
freepage = mapping->a_ops->freepage;
/*
@@ -1476,6 +1478,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
SetPageActive(page);
stat->nr_activate[type] += nr_pages;
count_memcg_page_event(page, PGACTIVATE);
+ workingset_activation(page);
}
keep_locked:
unlock_page(page);
--
2.7.4
