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-rw-r--r--mm/slub.c127
1 files changed, 119 insertions, 8 deletions
diff --git a/mm/slub.c b/mm/slub.c
index 20ab8f0..ac836d3 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -250,6 +250,7 @@ enum track_item { TRACK_ALLOC, TRACK_FREE };
static int sysfs_slab_add(struct kmem_cache *);
static int sysfs_slab_alias(struct kmem_cache *, const char *);
static void sysfs_slab_remove(struct kmem_cache *);
+
#else
static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)
@@ -258,8 +259,16 @@ static inline void sysfs_slab_remove(struct kmem_cache *s)
{
kfree(s);
}
+
#endif
+static inline void stat(struct kmem_cache_cpu *c, enum stat_item si)
+{
+#ifdef CONFIG_SLUB_STATS
+ c->stat[si]++;
+#endif
+}
+
/********************************************************************
* Core slab cache functions
*******************************************************************/
@@ -1364,17 +1373,22 @@ static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node)
static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail)
{
struct kmem_cache_node *n = get_node(s, page_to_nid(page));
+ struct kmem_cache_cpu *c = get_cpu_slab(s, smp_processor_id());
ClearSlabFrozen(page);
if (page->inuse) {
- if (page->freelist != page->end)
+ if (page->freelist != page->end) {
add_partial(n, page, tail);
- else if (SlabDebug(page) && (s->flags & SLAB_STORE_USER))
- add_full(n, page);
+ stat(c, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD);
+ } else {
+ stat(c, DEACTIVATE_FULL);
+ if (SlabDebug(page) && (s->flags & SLAB_STORE_USER))
+ add_full(n, page);
+ }
slab_unlock(page);
-
} else {
+ stat(c, DEACTIVATE_EMPTY);
if (n->nr_partial < MIN_PARTIAL) {
/*
* Adding an empty slab to the partial slabs in order
@@ -1388,6 +1402,7 @@ static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail)
slab_unlock(page);
} else {
slab_unlock(page);
+ stat(get_cpu_slab(s, raw_smp_processor_id()), FREE_SLAB);
discard_slab(s, page);
}
}
@@ -1400,6 +1415,9 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
{
struct page *page = c->page;
int tail = 1;
+
+ if (c->freelist)
+ stat(c, DEACTIVATE_REMOTE_FREES);
/*
* Merge cpu freelist into freelist. Typically we get here
* because both freelists are empty. So this is unlikely
@@ -1429,6 +1447,7 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
{
+ stat(c, CPUSLAB_FLUSH);
slab_lock(c->page);
deactivate_slab(s, c);
}
@@ -1511,6 +1530,7 @@ static void *__slab_alloc(struct kmem_cache *s,
slab_lock(c->page);
if (unlikely(!node_match(c, node)))
goto another_slab;
+ stat(c, ALLOC_REFILL);
load_freelist:
object = c->page->freelist;
if (unlikely(object == c->page->end))
@@ -1525,6 +1545,7 @@ load_freelist:
c->node = page_to_nid(c->page);
unlock_out:
slab_unlock(c->page);
+ stat(c, ALLOC_SLOWPATH);
out:
#ifdef SLUB_FASTPATH
local_irq_restore(flags);
@@ -1538,6 +1559,7 @@ new_slab:
new = get_partial(s, gfpflags, node);
if (new) {
c->page = new;
+ stat(c, ALLOC_FROM_PARTIAL);
goto load_freelist;
}
@@ -1551,6 +1573,7 @@ new_slab:
if (new) {
c = get_cpu_slab(s, smp_processor_id());
+ stat(c, ALLOC_SLAB);
if (c->page)
flush_slab(s, c);
slab_lock(new);
@@ -1610,6 +1633,7 @@ static __always_inline void *slab_alloc(struct kmem_cache *s,
object = __slab_alloc(s, gfpflags, node, addr, c);
break;
}
+ stat(c, ALLOC_FASTPATH);
} while (cmpxchg_local(&c->freelist, object, object[c->offset])
!= object);
#else
@@ -1624,6 +1648,7 @@ static __always_inline void *slab_alloc(struct kmem_cache *s,
else {
object = c->freelist;
c->freelist = object[c->offset];
+ stat(c, ALLOC_FASTPATH);
}
local_irq_restore(flags);
#endif
@@ -1661,12 +1686,15 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
{
void *prior;
void **object = (void *)x;
+ struct kmem_cache_cpu *c;
#ifdef SLUB_FASTPATH
unsigned long flags;
local_irq_save(flags);
#endif
+ c = get_cpu_slab(s, raw_smp_processor_id());
+ stat(c, FREE_SLOWPATH);
slab_lock(page);
if (unlikely(SlabDebug(page)))
@@ -1676,8 +1704,10 @@ checks_ok:
page->freelist = object;
page->inuse--;
- if (unlikely(SlabFrozen(page)))
+ if (unlikely(SlabFrozen(page))) {
+ stat(c, FREE_FROZEN);
goto out_unlock;
+ }
if (unlikely(!page->inuse))
goto slab_empty;
@@ -1687,8 +1717,10 @@ checks_ok:
* was not on the partial list before
* then add it.
*/
- if (unlikely(prior == page->end))
+ if (unlikely(prior == page->end)) {
add_partial(get_node(s, page_to_nid(page)), page, 1);
+ stat(c, FREE_ADD_PARTIAL);
+ }
out_unlock:
slab_unlock(page);
@@ -1698,13 +1730,15 @@ out_unlock:
return;
slab_empty:
- if (prior != page->end)
+ if (prior != page->end) {
/*
* Slab still on the partial list.
*/
remove_partial(s, page);
-
+ stat(c, FREE_REMOVE_PARTIAL);
+ }
slab_unlock(page);
+ stat(c, FREE_SLAB);
#ifdef SLUB_FASTPATH
local_irq_restore(flags);
#endif
@@ -1758,6 +1792,7 @@ static __always_inline void slab_free(struct kmem_cache *s,
break;
}
object[c->offset] = freelist;
+ stat(c, FREE_FASTPATH);
} while (cmpxchg_local(&c->freelist, freelist, object) != freelist);
#else
unsigned long flags;
@@ -1768,6 +1803,7 @@ static __always_inline void slab_free(struct kmem_cache *s,
if (likely(page == c->page && c->node >= 0)) {
object[c->offset] = c->freelist;
c->freelist = object;
+ stat(c, FREE_FASTPATH);
} else
__slab_free(s, page, x, addr, c->offset);
@@ -3980,6 +4016,62 @@ static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s,
SLAB_ATTR(remote_node_defrag_ratio);
#endif
+#ifdef CONFIG_SLUB_STATS
+
+static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si)
+{
+ unsigned long sum = 0;
+ int cpu;
+ int len;
+ int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL);
+
+ if (!data)
+ return -ENOMEM;
+
+ for_each_online_cpu(cpu) {
+ unsigned x = get_cpu_slab(s, cpu)->stat[si];
+
+ data[cpu] = x;
+ sum += x;
+ }
+
+ len = sprintf(buf, "%lu", sum);
+
+ for_each_online_cpu(cpu) {
+ if (data[cpu] && len < PAGE_SIZE - 20)
+ len += sprintf(buf + len, " c%d=%u", cpu, data[cpu]);
+ }
+ kfree(data);
+ return len + sprintf(buf + len, "\n");
+}
+
+#define STAT_ATTR(si, text) \
+static ssize_t text##_show(struct kmem_cache *s, char *buf) \
+{ \
+ return show_stat(s, buf, si); \
+} \
+SLAB_ATTR_RO(text); \
+
+STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath);
+STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath);
+STAT_ATTR(FREE_FASTPATH, free_fastpath);
+STAT_ATTR(FREE_SLOWPATH, free_slowpath);
+STAT_ATTR(FREE_FROZEN, free_frozen);
+STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial);
+STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial);
+STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial);
+STAT_ATTR(ALLOC_SLAB, alloc_slab);
+STAT_ATTR(ALLOC_REFILL, alloc_refill);
+STAT_ATTR(FREE_SLAB, free_slab);
+STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush);
+STAT_ATTR(DEACTIVATE_FULL, deactivate_full);
+STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty);
+STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head);
+STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail);
+STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees);
+
+#endif
+
static struct attribute *slab_attrs[] = {
&slab_size_attr.attr,
&object_size_attr.attr,
@@ -4010,6 +4102,25 @@ static struct attribute *slab_attrs[] = {
#ifdef CONFIG_NUMA
&remote_node_defrag_ratio_attr.attr,
#endif
+#ifdef CONFIG_SLUB_STATS
+ &alloc_fastpath_attr.attr,
+ &alloc_slowpath_attr.attr,
+ &free_fastpath_attr.attr,
+ &free_slowpath_attr.attr,
+ &free_frozen_attr.attr,
+ &free_add_partial_attr.attr,
+ &free_remove_partial_attr.attr,
+ &alloc_from_partial_attr.attr,
+ &alloc_slab_attr.attr,
+ &alloc_refill_attr.attr,
+ &free_slab_attr.attr,
+ &cpuslab_flush_attr.attr,
+ &deactivate_full_attr.attr,
+ &deactivate_empty_attr.attr,
+ &deactivate_to_head_attr.attr,
+ &deactivate_to_tail_attr.attr,
+ &deactivate_remote_frees_attr.attr,
+#endif
NULL
};
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