[PATCH v3 5/7] slub: Use slab_list instead of lru

Tobin C. Harding
2019-03-14T05:32:49Z

Currently we use the page->lru list for maintaining lists of slabs. We
have a list in the page structure (slab_list) that can be used for this
purpose. Doing so makes the code cleaner since we are not overloading
the lru list.

Use the slab_list instead of the lru list for maintaining lists of
slabs.

Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
---
mm/slub.c | 40 ++++++++++++++++++++--------------------
1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index b282e22885cd..d692b5e0163d 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1023,7 +1023,7 @@ static void add_full(struct kmem_cache *s,
return;

lockdep_assert_held(&n->list_lock);
- list_add(&page->lru, &n->full);
+ list_add(&page->slab_list, &n->full);
}

static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct page *page)
@@ -1032,7 +1032,7 @@ static void remove_full(struct kmem_cache *s, struct kmem_cache_node *n, struct
return;

lockdep_assert_held(&n->list_lock);
- list_del(&page->lru);
+ list_del(&page->slab_list);
}

/* Tracking of the number of slabs for debugging purposes */
@@ -1773,9 +1773,9 @@ __add_partial(struct kmem_cache_node *n, struct page *page, int tail)
{
n->nr_partial++;
if (tail == DEACTIVATE_TO_TAIL)
- list_add_tail(&page->lru, &n->partial);
+ list_add_tail(&page->slab_list, &n->partial);
else
- list_add(&page->lru, &n->partial);
+ list_add(&page->slab_list, &n->partial);
}

static inline void add_partial(struct kmem_cache_node *n,
@@ -1789,7 +1789,7 @@ static inline void remove_partial(struct kmem_cache_node *n,
struct page *page)
{
lockdep_assert_held(&n->list_lock);
- list_del(&page->lru);
+ list_del(&page->slab_list);
n->nr_partial--;
}

@@ -1863,7 +1863,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
return NULL;

spin_lock(&n->list_lock);
- list_for_each_entry_safe(page, page2, &n->partial, lru) {
+ list_for_each_entry_safe(page, page2, &n->partial, slab_list) {
void *t;

if (!pfmemalloc_match(page, flags))
@@ -2407,7 +2407,7 @@ static unsigned long count_partial(struct kmem_cache_node *n,
struct page *page;

spin_lock_irqsave(&n->list_lock, flags);
- list_for_each_entry(page, &n->partial, lru)
+ list_for_each_entry(page, &n->partial, slab_list)
x += get_count(page);
spin_unlock_irqrestore(&n->list_lock, flags);
return x;
@@ -3702,10 +3702,10 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)

BUG_ON(irqs_disabled());
spin_lock_irq(&n->list_lock);
- list_for_each_entry_safe(page, h, &n->partial, lru) {
+ list_for_each_entry_safe(page, h, &n->partial, slab_list) {
if (!page->inuse) {
remove_partial(n, page);
- list_add(&page->lru, &discard);
+ list_add(&page->slab_list, &discard);
} else {
list_slab_objects(s, page,
"Objects remaining in %s on __kmem_cache_shutdown()");
@@ -3713,7 +3713,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
}
spin_unlock_irq(&n->list_lock);

- list_for_each_entry_safe(page, h, &discard, lru)
+ list_for_each_entry_safe(page, h, &discard, slab_list)
discard_slab(s, page);
}

@@ -3993,7 +3993,7 @@ int __kmem_cache_shrink(struct kmem_cache *s)
* Note that concurrent frees may occur while we hold the
* list_lock. page->inuse here is the upper limit.
*/
- list_for_each_entry_safe(page, t, &n->partial, lru) {
+ list_for_each_entry_safe(page, t, &n->partial, slab_list) {
int free = page->objects - page->inuse;

/* Do not reread page->inuse */
@@ -4003,10 +4003,10 @@ int __kmem_cache_shrink(struct kmem_cache *s)
BUG_ON(free <= 0);

if (free == page->objects) {
- list_move(&page->lru, &discard);
+ list_move(&page->slab_list, &discard);
n->nr_partial--;
} else if (free <= SHRINK_PROMOTE_MAX)
- list_move(&page->lru, promote + free - 1);
+ list_move(&page->slab_list, promote + free - 1);
}

/*
@@ -4019,7 +4019,7 @@ int __kmem_cache_shrink(struct kmem_cache *s)
spin_unlock_irqrestore(&n->list_lock, flags);

/* Release empty slabs */
- list_for_each_entry_safe(page, t, &discard, lru)
+ list_for_each_entry_safe(page, t, &discard, slab_list)
discard_slab(s, page);

if (slabs_node(s, node))
@@ -4211,11 +4211,11 @@ static struct kmem_cache * __init bootstrap(struct kmem_cache *static_cache)
for_each_kmem_cache_node(s, node, n) {
struct page *p;

- list_for_each_entry(p, &n->partial, lru)
+ list_for_each_entry(p, &n->partial, slab_list)
p->slab_cache = s;

#ifdef CONFIG_SLUB_DEBUG
- list_for_each_entry(p, &n->full, lru)
+ list_for_each_entry(p, &n->full, slab_list)
p->slab_cache = s;
#endif
}
@@ -4432,7 +4432,7 @@ static int validate_slab_node(struct kmem_cache *s,

spin_lock_irqsave(&n->list_lock, flags);

- list_for_each_entry(page, &n->partial, lru) {
+ list_for_each_entry(page, &n->partial, slab_list) {
validate_slab_slab(s, page, map);
count++;
}
@@ -4443,7 +4443,7 @@ static int validate_slab_node(struct kmem_cache *s,
if (!(s->flags & SLAB_STORE_USER))
goto out;

- list_for_each_entry(page, &n->full, lru) {
+ list_for_each_entry(page, &n->full, slab_list) {
validate_slab_slab(s, page, map);
count++;
}
@@ -4639,9 +4639,9 @@ static int list_locations(struct kmem_cache *s, char *buf,
continue;

spin_lock_irqsave(&n->list_lock, flags);
- list_for_each_entry(page, &n->partial, lru)
+ list_for_each_entry(page, &n->partial, slab_list)
process_slab(&t, s, page, alloc, map);
- list_for_each_entry(page, &n->full, lru)
+ list_for_each_entry(page, &n->full, slab_list)
process_slab(&t, s, page, alloc, map);
spin_unlock_irqrestore(&n->list_lock, flags);
}
--
2.21.0