From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
The reserved field was only used for embedding an rcu_head in the data
structure. With the previous commit, we no longer need it. That lets
us remove the 'reserved' argument to a lot of functions.
Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
include/linux/slub_def.h | 1 -
mm/slub.c | 41 ++++++++++++++++++++--------------------
2 files changed, 20 insertions(+), 22 deletions(-)
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index 3773e26c08c1..09fa2c6f0e68 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -101,7 +101,6 @@ struct kmem_cache {
void (*ctor)(void *);
unsigned int inuse; /* Offset to metadata */
unsigned int align; /* Alignment */
- unsigned int reserved; /* Reserved bytes at the end of slabs */
unsigned int red_left_pad; /* Left redzone padding size */
const char *name; /* Name (only for display!) */
struct list_head list; /* List of slab caches */
diff --git a/mm/slub.c b/mm/slub.c
index 27cc2956acba..01c2183aa3d7 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -317,16 +317,16 @@ static inline unsigned int slab_index(void *p, struct kmem_cache *s, void *addr)
return (p - addr) / s->size;
}
-static inline unsigned int order_objects(unsigned int order, unsigned int size, unsigned int reserved)
+static inline unsigned int order_objects(unsigned int order, unsigned int size)
{
- return (((unsigned int)PAGE_SIZE << order) - reserved) / size;
+ return ((unsigned int)PAGE_SIZE << order) / size;
}
static inline struct kmem_cache_order_objects oo_make(unsigned int order,
- unsigned int size, unsigned int reserved)
+ unsigned int size)
{
struct kmem_cache_order_objects x = {
- (order << OO_SHIFT) + order_objects(order, size, reserved)
+ (order << OO_SHIFT) + order_objects(order, size)
};
return x;
@@ -841,7 +841,7 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page)
return 1;
start = page_address(page);
- length = (PAGE_SIZE << compound_order(page)) - s->reserved;
+ length = PAGE_SIZE << compound_order(page);
end = start + length;
remainder = length % s->size;
if (!remainder)
@@ -930,7 +930,7 @@ static int check_slab(struct kmem_cache *s, struct page *page)
return 0;
}
- maxobj = order_objects(compound_order(page), s->size, s->reserved);
+ maxobj = order_objects(compound_order(page), s->size);
if (page->objects > maxobj) {
slab_err(s, page, "objects %u > max %u",
page->objects, maxobj);
@@ -980,7 +980,7 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
nr++;
}
- max_objects = order_objects(compound_order(page), s->size, s->reserved);
+ max_objects = order_objects(compound_order(page), s->size);
if (max_objects > MAX_OBJS_PER_PAGE)
max_objects = MAX_OBJS_PER_PAGE;
@@ -3197,21 +3197,21 @@ static unsigned int slub_min_objects;
*/
static inline unsigned int slab_order(unsigned int size,
unsigned int min_objects, unsigned int max_order,
- unsigned int fract_leftover, unsigned int reserved)
+ unsigned int fract_leftover)
{
unsigned int min_order = slub_min_order;
unsigned int order;
- if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE)
+ if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE)
return get_order(size * MAX_OBJS_PER_PAGE) - 1;
- for (order = max(min_order, (unsigned int)get_order(min_objects * size + reserved));
+ for (order = max(min_order, (unsigned int)get_order(min_objects * size));
order <= max_order; order++) {
unsigned int slab_size = (unsigned int)PAGE_SIZE << order;
unsigned int rem;
- rem = (slab_size - reserved) % size;
+ rem = slab_size % size;
if (rem <= slab_size / fract_leftover)
break;
@@ -3220,7 +3220,7 @@ static inline unsigned int slab_order(unsigned int size,
return order;
}
-static inline int calculate_order(unsigned int size, unsigned int reserved)
+static inline int calculate_order(unsigned int size)
{
unsigned int order;
unsigned int min_objects;
@@ -3237,7 +3237,7 @@ static inline int calculate_order(unsigned int size, unsigned int reserved)
min_objects = slub_min_objects;
if (!min_objects)
min_objects = 4 * (fls(nr_cpu_ids) + 1);
- max_objects = order_objects(slub_max_order, size, reserved);
+ max_objects = order_objects(slub_max_order, size);
min_objects = min(min_objects, max_objects);
while (min_objects > 1) {
@@ -3246,7 +3246,7 @@ static inline int calculate_order(unsigned int size, unsigned int reserved)
fraction = 16;
while (fraction >= 4) {
order = slab_order(size, min_objects,
- slub_max_order, fraction, reserved);
+ slub_max_order, fraction);
if (order <= slub_max_order)
return order;
fraction /= 2;
@@ -3258,14 +3258,14 @@ static inline int calculate_order(unsigned int size, unsigned int reserved)
* We were unable to place multiple objects in a slab. Now
* lets see if we can place a single object there.
*/
- order = slab_order(size, 1, slub_max_order, 1, reserved);
+ order = slab_order(size, 1, slub_max_order, 1);
if (order <= slub_max_order)
return order;
/*
* Doh this slab cannot be placed using slub_max_order.
*/
- order = slab_order(size, 1, MAX_ORDER, 1, reserved);
+ order = slab_order(size, 1, MAX_ORDER, 1);
if (order < MAX_ORDER)
return order;
return -ENOSYS;
@@ -3533,7 +3533,7 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
if (forced_order >= 0)
order = forced_order;
else
- order = calculate_order(size, s->reserved);
+ order = calculate_order(size);
if ((int)order < 0)
return 0;
@@ -3551,8 +3551,8 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
/*
* Determine the number of objects per slab
*/
- s->oo = oo_make(order, size, s->reserved);
- s->min = oo_make(get_order(size), size, s->reserved);
+ s->oo = oo_make(order, size);
+ s->min = oo_make(get_order(size), size);
if (oo_objects(s->oo) > oo_objects(s->max))
s->max = s->oo;
@@ -3562,7 +3562,6 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags)
{
s->flags = kmem_cache_flags(s->size, flags, s->name, s->ctor);
- s->reserved = 0;
#ifdef CONFIG_SLAB_FREELIST_HARDENED
s->random = get_random_long();
#endif
@@ -5106,7 +5105,7 @@ SLAB_ATTR_RO(destroy_by_rcu);
static ssize_t reserved_show(struct kmem_cache *s, char *buf)
{
- return sprintf(buf, "%u\n", s->reserved);
+ return sprintf(buf, "0\n");
}
SLAB_ATTR_RO(reserved);
--
2.17.0
