dcache: allocate external names from reclaimable kmalloc caches

We can use the newly introduced kmalloc-reclaimable-X caches, to allocate
external names in dcache, which will take care of the proper accounting
automatically, and also improve anti-fragmentation page grouping.

This effectively reverts commit f1782c9bc5 ("dcache: account external
names as indirectly reclaimable memory") and instead passes
__GFP_RECLAIMABLE to kmalloc().  The accounting thus moves from
NR_INDIRECTLY_RECLAIMABLE_BYTES to NR_SLAB_RECLAIMABLE, which is also
considered in MemAvailable calculation and overcommit decisions.

Link: http://lkml.kernel.org/r/20180731090649.16028-4-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Vlastimil Babka 2018-10-26 15:05:41 -07:00 committed by Linus Torvalds
parent 1291523f2c
commit 2e03b4bc4a

View File

@ -257,24 +257,10 @@ static void __d_free(struct rcu_head *head)
kmem_cache_free(dentry_cache, dentry);
}
static void __d_free_external_name(struct rcu_head *head)
{
struct external_name *name = container_of(head, struct external_name,
u.head);
mod_node_page_state(page_pgdat(virt_to_page(name)),
NR_INDIRECTLY_RECLAIMABLE_BYTES,
-ksize(name));
kfree(name);
}
static void __d_free_external(struct rcu_head *head)
{
struct dentry *dentry = container_of(head, struct dentry, d_u.d_rcu);
__d_free_external_name(&external_name(dentry)->u.head);
kfree(external_name(dentry));
kmem_cache_free(dentry_cache, dentry);
}
@ -306,7 +292,7 @@ void release_dentry_name_snapshot(struct name_snapshot *name)
struct external_name *p;
p = container_of(name->name, struct external_name, name[0]);
if (unlikely(atomic_dec_and_test(&p->u.count)))
call_rcu(&p->u.head, __d_free_external_name);
kfree_rcu(p, u.head);
}
}
EXPORT_SYMBOL(release_dentry_name_snapshot);
@ -1606,7 +1592,6 @@ EXPORT_SYMBOL(d_invalidate);
struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name)
{
struct external_name *ext = NULL;
struct dentry *dentry;
char *dname;
int err;
@ -1627,14 +1612,15 @@ struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name)
dname = dentry->d_iname;
} else if (name->len > DNAME_INLINE_LEN-1) {
size_t size = offsetof(struct external_name, name[1]);
ext = kmalloc(size + name->len, GFP_KERNEL_ACCOUNT);
if (!ext) {
struct external_name *p = kmalloc(size + name->len,
GFP_KERNEL_ACCOUNT |
__GFP_RECLAIMABLE);
if (!p) {
kmem_cache_free(dentry_cache, dentry);
return NULL;
}
atomic_set(&ext->u.count, 1);
dname = ext->name;
atomic_set(&p->u.count, 1);
dname = p->name;
} else {
dname = dentry->d_iname;
}
@ -1673,12 +1659,6 @@ struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name)
}
}
if (unlikely(ext)) {
pg_data_t *pgdat = page_pgdat(virt_to_page(ext));
mod_node_page_state(pgdat, NR_INDIRECTLY_RECLAIMABLE_BYTES,
ksize(ext));
}
this_cpu_inc(nr_dentry);
return dentry;
@ -2707,7 +2687,7 @@ static void copy_name(struct dentry *dentry, struct dentry *target)
dentry->d_name.hash_len = target->d_name.hash_len;
}
if (old_name && likely(atomic_dec_and_test(&old_name->u.count)))
call_rcu(&old_name->u.head, __d_free_external_name);
kfree_rcu(old_name, u.head);
}
/*