libceph: add ceph_kv{malloc,free}() and switch to them

Encapsulate kmalloc vs vmalloc memory allocation and freeing logic into
two helpers, ceph_kvmalloc() and ceph_kvfree(), and switch to them.

ceph_kvmalloc() kmalloc()'s a maximum of 8 pages, anything bigger is
vmalloc()'ed with __GFP_HIGHMEM set.  This changes the existing
behaviour:

- for buffers (ceph_buffer_new()), from trying to kmalloc() everything
  and using vmalloc() just as a fallback

- for messages (ceph_msg_new()), from going to vmalloc() for anything
  bigger than a page

- for messages (ceph_msg_new()), from disallowing vmalloc() to use high
  memory

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
This commit is contained in:
Ilya Dryomov 2014-01-09 20:08:21 +02:00
parent 80213a84a9
commit eeb0bed557
6 changed files with 35 additions and 33 deletions

View file

@ -17,7 +17,6 @@ struct ceph_buffer {
struct kref kref;
struct kvec vec;
size_t alloc_len;
bool is_vmalloc;
};
extern struct ceph_buffer *ceph_buffer_new(size_t len, gfp_t gfp);

View file

@ -173,15 +173,18 @@ static inline int calc_pages_for(u64 off, u64 len)
(off >> PAGE_CACHE_SHIFT);
}
extern struct kmem_cache *ceph_inode_cachep;
extern struct kmem_cache *ceph_cap_cachep;
extern struct kmem_cache *ceph_dentry_cachep;
extern struct kmem_cache *ceph_file_cachep;
/* ceph_common.c */
extern bool libceph_compatible(void *data);
extern const char *ceph_msg_type_name(int type);
extern int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid);
extern struct kmem_cache *ceph_inode_cachep;
extern struct kmem_cache *ceph_cap_cachep;
extern struct kmem_cache *ceph_dentry_cachep;
extern struct kmem_cache *ceph_file_cachep;
extern void *ceph_kvmalloc(size_t size, gfp_t flags);
extern void ceph_kvfree(const void *ptr);
extern struct ceph_options *ceph_parse_options(char *options,
const char *dev_name, const char *dev_name_end,

View file

@ -154,7 +154,6 @@ struct ceph_msg {
struct list_head list_head; /* links for connection lists */
struct kref kref;
bool front_is_vmalloc;
bool more_to_follow;
bool needs_out_seq;
int front_alloc_len;

View file

@ -6,6 +6,7 @@
#include <linux/ceph/buffer.h>
#include <linux/ceph/decode.h>
#include <linux/ceph/libceph.h> /* for ceph_kv{malloc,free} */
struct ceph_buffer *ceph_buffer_new(size_t len, gfp_t gfp)
{
@ -15,16 +16,10 @@ struct ceph_buffer *ceph_buffer_new(size_t len, gfp_t gfp)
if (!b)
return NULL;
b->vec.iov_base = kmalloc(len, gfp | __GFP_NOWARN);
if (b->vec.iov_base) {
b->is_vmalloc = false;
} else {
b->vec.iov_base = __vmalloc(len, gfp | __GFP_HIGHMEM, PAGE_KERNEL);
if (!b->vec.iov_base) {
kfree(b);
return NULL;
}
b->is_vmalloc = true;
b->vec.iov_base = ceph_kvmalloc(len, gfp);
if (!b->vec.iov_base) {
kfree(b);
return NULL;
}
kref_init(&b->kref);
@ -40,12 +35,7 @@ void ceph_buffer_release(struct kref *kref)
struct ceph_buffer *b = container_of(kref, struct ceph_buffer, kref);
dout("buffer_release %p\n", b);
if (b->vec.iov_base) {
if (b->is_vmalloc)
vfree(b->vec.iov_base);
else
kfree(b->vec.iov_base);
}
ceph_kvfree(b->vec.iov_base);
kfree(b);
}
EXPORT_SYMBOL(ceph_buffer_release);

View file

@ -15,6 +15,7 @@
#include <linux/slab.h>
#include <linux/statfs.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/nsproxy.h>
#include <net/net_namespace.h>
@ -170,6 +171,25 @@ int ceph_compare_options(struct ceph_options *new_opt,
}
EXPORT_SYMBOL(ceph_compare_options);
void *ceph_kvmalloc(size_t size, gfp_t flags)
{
if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
void *ptr = kmalloc(size, flags | __GFP_NOWARN);
if (ptr)
return ptr;
}
return __vmalloc(size, flags | __GFP_HIGHMEM, PAGE_KERNEL);
}
void ceph_kvfree(const void *ptr)
{
if (is_vmalloc_addr(ptr))
vfree(ptr);
else
kfree(ptr);
}
static int parse_fsid(const char *str, struct ceph_fsid *fsid)
{

View file

@ -3131,13 +3131,7 @@ struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
/* front */
if (front_len) {
if (front_len > PAGE_CACHE_SIZE) {
m->front.iov_base = __vmalloc(front_len, flags,
PAGE_KERNEL);
m->front_is_vmalloc = true;
} else {
m->front.iov_base = kmalloc(front_len, flags);
}
m->front.iov_base = ceph_kvmalloc(front_len, flags);
if (m->front.iov_base == NULL) {
dout("ceph_msg_new can't allocate %d bytes\n",
front_len);
@ -3259,10 +3253,7 @@ static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip)
void ceph_msg_kfree(struct ceph_msg *m)
{
dout("msg_kfree %p\n", m);
if (m->front_is_vmalloc)
vfree(m->front.iov_base);
else
kfree(m->front.iov_base);
ceph_kvfree(m->front.iov_base);
kmem_cache_free(ceph_msg_cache, m);
}