NFS: Readdir plus in v4

By requsting more attributes during a readdir, we can mimic the readdir plus
operation that was in NFSv3.

To test, I ran the command `ls -lU --color=none` on directories with various
numbers of files.  Without readdir plus, I see this:

n files |    100    |   1,000   |  10,000   |  100,000  | 1,000,000
--------+-----------+-----------+-----------+-----------+----------
real    | 0m00.153s | 0m00.589s | 0m05.601s | 0m56.691s | 9m59.128s
user    | 0m00.007s | 0m00.007s | 0m00.077s | 0m00.703s | 0m06.800s
sys     | 0m00.010s | 0m00.070s | 0m00.633s | 0m06.423s | 1m10.005s
access  | 3         | 1         | 1         | 4         | 31
getattr | 2         | 1         | 1         | 1         | 1
lookup  | 104       | 1,003     | 10,003    | 100,003   | 1,000,003
readdir | 2         | 16        | 158       | 1,575     | 15,749
total   | 111       | 1,021     | 10,163    | 101,583   | 1,015,784

With readdir plus enabled, I see this:

n files |    100    |   1,000   |  10,000   |  100,000  | 1,000,000
--------+-----------+-----------+-----------+-----------+----------
real    | 0m00.115s | 0m00.206s | 0m01.079s | 0m12.521s | 2m07.528s
user    | 0m00.003s | 0m00.003s | 0m00.040s | 0m00.290s | 0m03.296s
sys     | 0m00.007s | 0m00.020s | 0m00.120s | 0m01.357s | 0m17.556s
access  | 3         | 1         | 1         | 1         | 7
getattr | 2         | 1         | 1         | 1         | 1
lookup  | 4         | 3         | 3         | 3         | 3
readdir | 6         | 62        | 630       | 6,300     | 62,993
total   | 15        | 67        | 635       | 6,305     | 63,004

Readdir plus disabled has about a 16x increase in the number of rpc calls and
is 4 - 5 times slower on large directories.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Bryan Schumaker 2010-10-21 16:33:18 -04:00 committed by Trond Myklebust
parent ae42c70a60
commit 82f2e5472e
9 changed files with 41 additions and 39 deletions

View File

@ -1358,8 +1358,9 @@ static int nfs4_init_server(struct nfs_server *server,
/* Initialise the client representation from the mount data */
server->flags = data->flags;
server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|
NFS_CAP_POSIX_LOCK;
server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|NFS_CAP_POSIX_LOCK;
if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
server->caps |= NFS_CAP_READDIRPLUS;
server->options = data->options;
/* Get a client record */

View File

@ -172,7 +172,7 @@ struct nfs_cache_array {
#define MAX_READDIR_ARRAY ((PAGE_SIZE - sizeof(struct nfs_cache_array)) / sizeof(struct nfs_cache_array_entry))
typedef __be32 * (*decode_dirent_t)(struct xdr_stream *, struct nfs_entry *, int);
typedef __be32 * (*decode_dirent_t)(struct xdr_stream *, struct nfs_entry *, struct nfs_server *, int);
typedef struct {
struct file *file;
struct page *page;
@ -360,7 +360,7 @@ error:
static
int xdr_decode(nfs_readdir_descriptor_t *desc, struct nfs_entry *entry, struct xdr_stream *stream)
{
__be32 *p = desc->decode(stream, entry, desc->plus);
__be32 *p = desc->decode(stream, entry, NFS_SERVER(desc->file->f_path.dentry->d_inode), desc->plus);
if (IS_ERR(p))
return PTR_ERR(p);

View File

@ -187,15 +187,15 @@ extern void nfs_destroy_directcache(void);
/* nfs2xdr.c */
extern int nfs_stat_to_errno(int);
extern struct rpc_procinfo nfs_procedures[];
extern __be32 *nfs_decode_dirent(struct xdr_stream *, struct nfs_entry *, int);
extern __be32 *nfs_decode_dirent(struct xdr_stream *, struct nfs_entry *, struct nfs_server *, int);
/* nfs3xdr.c */
extern struct rpc_procinfo nfs3_procedures[];
extern __be32 *nfs3_decode_dirent(struct xdr_stream *, struct nfs_entry *, int);
extern __be32 *nfs3_decode_dirent(struct xdr_stream *, struct nfs_entry *, struct nfs_server *, int);
/* nfs4xdr.c */
#ifdef CONFIG_NFS_V4
extern __be32 *nfs4_decode_dirent(struct xdr_stream *, struct nfs_entry *entry, int plus);
extern __be32 *nfs4_decode_dirent(struct xdr_stream *, struct nfs_entry *, struct nfs_server *, int);
#endif
#ifdef CONFIG_NFS_V4_1
extern const u32 nfs41_maxread_overhead;

View File

@ -454,7 +454,7 @@ static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
}
__be32 *
nfs_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, int plus)
nfs_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, struct nfs_server *server, int plus)
{
__be32 *p;
p = xdr_inline_decode(xdr, 4);

View File

@ -590,7 +590,7 @@ nfs3_xdr_readdirres(struct rpc_rqst *req, __be32 *p, struct nfs3_readdirres *res
}
__be32 *
nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, int plus)
nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, struct nfs_server *server, int plus)
{
__be32 *p;
struct nfs_entry old = *entry;

View File

@ -331,7 +331,7 @@ extern void nfs_free_seqid(struct nfs_seqid *seqid);
extern const nfs4_stateid zero_stateid;
/* nfs4xdr.c */
extern __be32 *nfs4_decode_dirent(struct xdr_stream *, struct nfs_entry *entry, int plus);
extern __be32 *nfs4_decode_dirent(struct xdr_stream *, struct nfs_entry *, struct nfs_server *, int);
extern struct rpc_procinfo nfs4_procedures[];
struct nfs4_mount_data;

View File

@ -2832,6 +2832,7 @@ static int _nfs4_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,
.pgbase = 0,
.count = count,
.bitmask = NFS_SERVER(dentry->d_inode)->attr_bitmask,
.plus = plus,
};
struct nfs4_readdir_res res;
struct rpc_message msg = {

View File

@ -1385,12 +1385,20 @@ static void encode_read(struct xdr_stream *xdr, const struct nfs_readargs *args,
static void encode_readdir(struct xdr_stream *xdr, const struct nfs4_readdir_arg *readdir, struct rpc_rqst *req, struct compound_hdr *hdr)
{
uint32_t attrs[2] = {
FATTR4_WORD0_RDATTR_ERROR|FATTR4_WORD0_FILEID,
FATTR4_WORD1_MOUNTED_ON_FILEID,
};
uint32_t attrs[2] = {0, 0};
__be32 *p;
if (readdir->plus) {
attrs[0] |= FATTR4_WORD0_TYPE|FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE|
FATTR4_WORD0_FSID|FATTR4_WORD0_FILEHANDLE;
attrs[1] |= FATTR4_WORD1_MODE|FATTR4_WORD1_NUMLINKS|FATTR4_WORD1_OWNER|
FATTR4_WORD1_OWNER_GROUP|FATTR4_WORD1_RAWDEV|
FATTR4_WORD1_SPACE_USED|FATTR4_WORD1_TIME_ACCESS|
FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY;
}
attrs[0] |= FATTR4_WORD0_RDATTR_ERROR|FATTR4_WORD0_FILEID;
attrs[1] |= FATTR4_WORD1_MOUNTED_ON_FILEID;
p = reserve_space(xdr, 12+NFS4_VERIFIER_SIZE+20);
*p++ = cpu_to_be32(OP_READDIR);
p = xdr_encode_hyper(p, readdir->cookie);
@ -1398,11 +1406,15 @@ static void encode_readdir(struct xdr_stream *xdr, const struct nfs4_readdir_arg
*p++ = cpu_to_be32(readdir->count >> 1); /* We're not doing readdirplus */
*p++ = cpu_to_be32(readdir->count);
*p++ = cpu_to_be32(2);
/* Switch to mounted_on_fileid if the server supports it */
if (readdir->bitmask[1] & FATTR4_WORD1_MOUNTED_ON_FILEID)
attrs[0] &= ~FATTR4_WORD0_FILEID;
else
attrs[1] &= ~FATTR4_WORD1_MOUNTED_ON_FILEID;
if (!readdir->plus) {
/* Switch to mounted_on_fileid if the server supports it */
if (readdir->bitmask[1] & FATTR4_WORD1_MOUNTED_ON_FILEID)
attrs[0] &= ~FATTR4_WORD0_FILEID;
else
attrs[1] &= ~FATTR4_WORD1_MOUNTED_ON_FILEID;
}
*p++ = cpu_to_be32(attrs[0] & readdir->bitmask[0]);
*p = cpu_to_be32(attrs[1] & readdir->bitmask[1]);
hdr->nops++;
@ -5768,7 +5780,8 @@ static int nfs4_xdr_dec_reclaim_complete(struct rpc_rqst *rqstp, uint32_t *p,
}
#endif /* CONFIG_NFS_V4_1 */
__be32 *nfs4_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, int plus)
__be32 *nfs4_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
struct nfs_server *server, int plus)
{
uint32_t bitmap[2] = {0};
uint32_t len;
@ -5824,24 +5837,10 @@ __be32 *nfs4_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, int
goto out_overflow;
len = XDR_QUADLEN(ntohl(*p++)); /* attribute buffer length */
if (len > 0) {
if (bitmap[0] & FATTR4_WORD0_RDATTR_ERROR) {
bitmap[0] &= ~FATTR4_WORD0_RDATTR_ERROR;
/* Ignore the return value of rdattr_error for now */
p = xdr_inline_decode(xdr, 4);
if (unlikely(!p))
goto out_overflow;
}
if (bitmap[0] == 0 && bitmap[1] == FATTR4_WORD1_MOUNTED_ON_FILEID) {
p = xdr_inline_decode(xdr, 8);
if (unlikely(!p))
goto out_overflow;
xdr_decode_hyper(p, &entry->ino);
} else if (bitmap[0] == FATTR4_WORD0_FILEID) {
p = xdr_inline_decode(xdr, 8);
if (unlikely(!p))
goto out_overflow;
xdr_decode_hyper(p, &entry->ino);
}
if (decode_getfattr_attrs(xdr, bitmap, entry->fattr, entry->fh, server, 1) < 0)
goto out_overflow;
if (entry->fattr->valid & NFS_ATTR_FATTR_FILEID)
entry->ino = entry->fattr->fileid;
}
p = xdr_inline_peek(xdr, 8);

View File

@ -778,6 +778,7 @@ struct nfs4_readdir_arg {
struct page ** pages; /* zero-copy data */
unsigned int pgbase; /* zero-copy data */
const u32 * bitmask;
int plus;
struct nfs4_sequence_args seq_args;
};
@ -1036,7 +1037,7 @@ struct nfs_rpc_ops {
int (*pathconf) (struct nfs_server *, struct nfs_fh *,
struct nfs_pathconf *);
int (*set_capabilities)(struct nfs_server *, struct nfs_fh *);
__be32 *(*decode_dirent)(struct xdr_stream *, struct nfs_entry *, int plus);
__be32 *(*decode_dirent)(struct xdr_stream *, struct nfs_entry *, struct nfs_server *, int plus);
void (*read_setup) (struct nfs_read_data *, struct rpc_message *);
int (*read_done) (struct rpc_task *, struct nfs_read_data *);
void (*write_setup) (struct nfs_write_data *, struct rpc_message *);