Add a timeout on positive name cache entries in the NFS client. That is,

we will only trust a positive name cache entry for a specified amount of
time before falling back to a LOOKUP RPC, even if the ctime for the file
handle matches the cached copy in the name cache entry.  The timeout is
configured via a new 'nametimeo' mount option and defaults to 60 seconds.
It may be set to zero to disable positive name caching entirely.

Reviewed by:	rmacklem
MFC after:	1 week
This commit is contained in:
John Baldwin 2012-01-25 20:05:58 +00:00
parent 07dbb38763
commit 0b17c7bea5
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=230547
7 changed files with 59 additions and 18 deletions

View File

@ -157,6 +157,10 @@ Force the mount protocol to use UDP transport, even for TCP NFS mounts.
(Necessary for some old
.Bx
servers.)
.It Cm nametimeo Ns = Ns Aq Ar value
Override the default of NFS_DEFAULT_NAMETIMEO for the timeout (in seconds)
for positive name cache entries.
If this is set to 0 it disables positive name caching for the mount point.
.It Cm negnametimeo Ns = Ns Aq Ar value
Override the default of NFS_DEFAULT_NEGNAMETIMEO for the timeout (in seconds)
for negative name cache entries. If this is set to 0 it disables negative

View File

@ -104,7 +104,7 @@ static void nfs_decode_args(struct mount *mp, struct nfsmount *nmp,
static int mountnfs(struct nfs_args *, struct mount *,
struct sockaddr *, char *, u_char *, int, u_char *, int,
u_char *, int, struct vnode **, struct ucred *,
struct thread *, int);
struct thread *, int, int);
static void nfs_getnlminfo(struct vnode *, uint8_t *, size_t *,
struct sockaddr_storage *, int *, off_t *,
struct timeval *);
@ -520,7 +520,8 @@ nfs_mountdiskless(char *path,
dirlen = 0;
nam = sodupsockaddr((struct sockaddr *)sin, M_WAITOK);
if ((error = mountnfs(args, mp, nam, path, NULL, 0, dirpath, dirlen,
NULL, 0, vpp, td->td_ucred, td, NFS_DEFAULT_NEGNAMETIMEO)) != 0) {
NULL, 0, vpp, td->td_ucred, td, NFS_DEFAULT_NAMETIMEO,
NFS_DEFAULT_NEGNAMETIMEO)) != 0) {
printf("nfs_mountroot: mount %s on /: %d\n", path, error);
return (error);
}
@ -715,7 +716,7 @@ static const char *nfs_opts[] = { "from", "nfs_args",
"retrans", "acregmin", "acregmax", "acdirmin", "acdirmax", "resvport",
"readahead", "hostname", "timeout", "addr", "fh", "nfsv3", "sec",
"principal", "nfsv4", "gssname", "allgssname", "dirpath",
"negnametimeo", "nocto", "wcommitsize",
"nametimeo", "negnametimeo", "nocto", "wcommitsize",
NULL };
/*
@ -760,6 +761,7 @@ nfs_mount(struct mount *mp)
char hst[MNAMELEN];
u_char nfh[NFSX_FHMAX], krbname[100], dirpath[100], srvkrbname[100];
char *opt, *name, *secname;
int nametimeo = NFS_DEFAULT_NAMETIMEO;
int negnametimeo = NFS_DEFAULT_NEGNAMETIMEO;
int dirlen, has_nfs_args_opt, krbnamelen, srvkrbnamelen;
size_t hstlen;
@ -968,6 +970,14 @@ nfs_mount(struct mount *mp)
}
args.flags |= NFSMNT_TIMEO;
}
if (vfs_getopt(mp->mnt_optnew, "nametimeo", (void **)&opt, NULL) == 0) {
ret = sscanf(opt, "%d", &nametimeo);
if (ret != 1 || nametimeo < 0) {
vfs_mount_error(mp, "illegal nametimeo: %s", opt);
error = EINVAL;
goto out;
}
}
if (vfs_getopt(mp->mnt_optnew, "negnametimeo", (void **)&opt, NULL)
== 0) {
ret = sscanf(opt, "%d", &negnametimeo);
@ -1126,7 +1136,7 @@ nfs_mount(struct mount *mp)
args.fh = nfh;
error = mountnfs(&args, mp, nam, hst, krbname, krbnamelen, dirpath,
dirlen, srvkrbname, srvkrbnamelen, &vp, td->td_ucred, td,
negnametimeo);
nametimeo, negnametimeo);
out:
if (!error) {
MNT_ILOCK(mp);
@ -1170,7 +1180,7 @@ static int
mountnfs(struct nfs_args *argp, struct mount *mp, struct sockaddr *nam,
char *hst, u_char *krbname, int krbnamelen, u_char *dirpath, int dirlen,
u_char *srvkrbname, int srvkrbnamelen, struct vnode **vpp,
struct ucred *cred, struct thread *td, int negnametimeo)
struct ucred *cred, struct thread *td, int nametimeo, int negnametimeo)
{
struct nfsmount *nmp;
struct nfsnode *np;
@ -1237,13 +1247,14 @@ mountnfs(struct nfs_args *argp, struct mount *mp, struct sockaddr *nam,
}
vfs_getnewfsid(mp);
nmp->nm_mountp = mp;
mtx_init(&nmp->nm_mtx, "NFSmount lock", NULL, MTX_DEF | MTX_DUPOK);
mtx_init(&nmp->nm_mtx, "NFSmount lock", NULL, MTX_DEF | MTX_DUPOK);
/*
* Since nfs_decode_args() might optionally set them, these need to
* set to defaults before the call, so that the optional settings
* aren't overwritten.
* Since nfs_decode_args() might optionally set them, these
* need to be set to defaults before the call, so that the
* optional settings aren't overwritten.
*/
nmp->nm_nametimeo = nametimeo;
nmp->nm_negnametimeo = negnametimeo;
nmp->nm_timeo = NFS_TIMEO;
nmp->nm_retry = NFS_RETRANS;

View File

@ -1063,7 +1063,8 @@ nfs_lookup(struct vop_lookup_args *ap)
* We only accept a positive hit in the cache if the
* change time of the file matches our cached copy.
* Otherwise, we discard the cache entry and fallback
* to doing a lookup RPC.
* to doing a lookup RPC. We also only trust cache
* entries for less than nm_nametimeo seconds.
*
* To better handle stale file handles and attributes,
* clear the attribute cache of this node if it is a
@ -1085,7 +1086,8 @@ nfs_lookup(struct vop_lookup_args *ap)
mtx_unlock(&newnp->n_mtx);
}
if (nfscl_nodeleg(newvp, 0) == 0 ||
(VOP_GETATTR(newvp, &vattr, cnp->cn_cred) == 0 &&
((u_int)(ticks - ncticks) < (nmp->nm_nametimeo * hz) &&
VOP_GETATTR(newvp, &vattr, cnp->cn_cred) == 0 &&
timespeccmp(&vattr.va_ctime, &nctime, ==))) {
NFSINCRGLOBAL(newnfsstats.lookupcache_hits);
if (cnp->cn_nameiop != LOOKUP &&

View File

@ -66,6 +66,7 @@ struct nfsmount {
u_int64_t nm_maxfilesize; /* maximum file size */
int nm_tprintf_initial_delay; /* initial delay */
int nm_tprintf_delay; /* interval for messages */
int nm_nametimeo; /* timeout for +ve entries (sec) */
int nm_negnametimeo; /* timeout for -ve entries (sec) */
/* Newnfs additions */
@ -106,6 +107,10 @@ struct nfsmount {
*/
#define VFSTONFS(mp) ((struct nfsmount *)((mp)->mnt_data))
#ifndef NFS_DEFAULT_NAMETIMEO
#define NFS_DEFAULT_NAMETIMEO 60
#endif
#ifndef NFS_DEFAULT_NEGNAMETIMEO
#define NFS_DEFAULT_NEGNAMETIMEO 60
#endif

View File

@ -117,7 +117,7 @@ static void nfs_decode_args(struct mount *mp, struct nfsmount *nmp,
struct nfs_args *argp, const char *hostname);
static int mountnfs(struct nfs_args *, struct mount *,
struct sockaddr *, char *, struct vnode **,
struct ucred *cred, int);
struct ucred *cred, int, int);
static void nfs_getnlminfo(struct vnode *, uint8_t *, size_t *,
struct sockaddr_storage *, int *, off_t *,
struct timeval *);
@ -559,8 +559,8 @@ nfs_mountdiskless(char *path,
int error;
nam = sodupsockaddr((struct sockaddr *)sin, M_WAITOK);
if ((error = mountnfs(args, mp, nam, path, vpp,
td->td_ucred, NFS_DEFAULT_NEGNAMETIMEO)) != 0) {
if ((error = mountnfs(args, mp, nam, path, vpp, td->td_ucred,
NFS_DEFAULT_NAMETIMEO, NFS_DEFAULT_NEGNAMETIMEO)) != 0) {
printf("nfs_mountroot: mount %s on /: %d\n", path, error);
return (error);
}
@ -788,6 +788,7 @@ static const char *nfs_opts[] = { "from", "nfs_args",
"wsize", "rsize", "retrans", "acregmin", "acregmax", "acdirmin",
"acdirmax", "deadthresh", "hostname", "timeout", "addr", "fh", "nfsv3",
"sec", "maxgroups", "principal", "negnametimeo", "nocto", "wcommitsize",
"nametimeo",
NULL };
/*
@ -836,6 +837,7 @@ nfs_mount(struct mount *mp)
size_t len;
u_char nfh[NFSX_V3FHMAX];
char *opt;
int nametimeo = NFS_DEFAULT_NAMETIMEO;
int negnametimeo = NFS_DEFAULT_NEGNAMETIMEO;
has_nfs_args_opt = 0;
@ -1058,6 +1060,14 @@ nfs_mount(struct mount *mp)
}
args.flags |= NFSMNT_MAXGRPS;
}
if (vfs_getopt(mp->mnt_optnew, "nametimeo", (void **)&opt, NULL) == 0) {
ret = sscanf(opt, "%d", &nametimeo);
if (ret != 1 || nametimeo < 0) {
vfs_mount_error(mp, "illegal nametimeo: %s", opt);
error = EINVAL;
goto out;
}
}
if (vfs_getopt(mp->mnt_optnew, "negnametimeo", (void **)&opt, NULL)
== 0) {
ret = sscanf(opt, "%d", &negnametimeo);
@ -1182,7 +1192,7 @@ nfs_mount(struct mount *mp)
goto out;
}
error = mountnfs(&args, mp, nam, args.hostname, &vp,
curthread->td_ucred, negnametimeo);
curthread->td_ucred, nametimeo, negnametimeo);
out:
if (!error) {
MNT_ILOCK(mp);
@ -1224,7 +1234,8 @@ nfs_cmount(struct mntarg *ma, void *data, uint64_t flags)
*/
static int
mountnfs(struct nfs_args *argp, struct mount *mp, struct sockaddr *nam,
char *hst, struct vnode **vpp, struct ucred *cred, int negnametimeo)
char *hst, struct vnode **vpp, struct ucred *cred, int nametimeo,
int negnametimeo)
{
struct nfsmount *nmp;
struct nfsnode *np;
@ -1274,6 +1285,7 @@ mountnfs(struct nfs_args *argp, struct mount *mp, struct sockaddr *nam,
nmp->nm_numgrps = NFS_MAXGRPS;
nmp->nm_readahead = NFS_DEFRAHEAD;
nmp->nm_deadthresh = NFS_MAXDEADTHRESH;
nmp->nm_nametimeo = nametimeo;
nmp->nm_negnametimeo = negnametimeo;
nmp->nm_tprintf_delay = nfs_tprintf_delay;
if (nmp->nm_tprintf_delay < 0)

View File

@ -959,7 +959,8 @@ nfs_lookup(struct vop_lookup_args *ap)
* We only accept a positive hit in the cache if the
* change time of the file matches our cached copy.
* Otherwise, we discard the cache entry and fallback
* to doing a lookup RPC.
* to doing a lookup RPC. We also only trust cache
* entries for less than nm_nametimeo seconds.
*
* To better handle stale file handles and attributes,
* clear the attribute cache of this node if it is a
@ -980,7 +981,8 @@ nfs_lookup(struct vop_lookup_args *ap)
KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(newvp);
mtx_unlock(&newnp->n_mtx);
}
if (VOP_GETATTR(newvp, &vattr, cnp->cn_cred) == 0 &&
if ((u_int)(ticks - ncticks) < (nmp->nm_nametimeo * hz) &&
VOP_GETATTR(newvp, &vattr, cnp->cn_cred) == 0 &&
timespeccmp(&vattr.va_ctime, &nctime, ==)) {
nfsstats.lookupcache_hits++;
if (cnp->cn_nameiop != LOOKUP &&

View File

@ -83,6 +83,7 @@ struct nfsmount {
struct rpc_timers nm_timers[NFS_MAX_TIMER]; /* RTT Timers for rpcs */
char nm_principal[MNAMELEN]; /* GSS-API principal of server */
gss_OID nm_mech_oid; /* OID of selected GSS-API mechanism */
int nm_nametimeo; /* timeout for +ve entries (sec) */
int nm_negnametimeo; /* timeout for -ve entries (sec) */
/* NFSv4 */
@ -116,6 +117,10 @@ struct nfsmount {
#define NFS_TPRINTF_DELAY 30
#endif
#ifndef NFS_DEFAULT_NAMETIMEO
#define NFS_DEFAULT_NAMETIMEO 60
#endif
#ifndef NFS_DEFAULT_NEGNAMETIMEO
#define NFS_DEFAULT_NEGNAMETIMEO 60
#endif