From: Trond Myklebust <[email protected]>
The current NFS readdir code will always try to maximise the amount of
readahead it performs on the assumption that we can cache anything that
isn't immediately read by the process.
There are several cases where this assumption breaks down, including
when the 'ls -l' heuristic kicks in to try to force use of readdirplus
as a batch replacement for lookup/getattr.
--
v2: Remove reset of dtsize when NFS_INO_FORCE_READDIR is set
v3: Avoid excessive window shrinking in uncached_readdir case
v4: Track 'ls -l' cache hit/miss statistics
Improved algorithm for falling back to uncached readdir
Skip readdirplus when files are being written to
v5: bugfixes
Skip readdirplus when the acdirmax/acregmax values are low
Request a full XDR buffer when doing READDIRPLUS
v6: Add tracing
Don't have lookup request readdirplus when it won't help
Trond Myklebust (13):
NFS: constify nfs_server_capable() and nfs_have_writebacks()
NFS: Trace lookup revalidation failure
NFS: Adjust the amount of readahead performed by NFS readdir
NFS: Simplify nfs_readdir_xdr_to_array()
NFS: Improve algorithm for falling back to uncached readdir
NFS: Improve heuristic for readdirplus
NFS: Don't ask for readdirplus unless it can help nfs_getattr()
NFSv4: Ask for a full XDR buffer of readdir goodness
NFS: Readdirplus can't help lookup for case insensitive filesystems
NFS: Don't request readdirplus when revaldation was forced
NFS: Add basic readdir tracing
NFS: Trace effects of readdirplus on the dcache
NFS: Trace effects of the readdirplus heuristic
fs/nfs/dir.c | 275 +++++++++++++++++++++++++++--------------
fs/nfs/inode.c | 37 +++---
fs/nfs/internal.h | 4 +-
fs/nfs/nfs3xdr.c | 7 +-
fs/nfs/nfs4xdr.c | 6 +-
fs/nfs/nfstrace.h | 122 +++++++++++++++++-
include/linux/nfs_fs.h | 14 ++-
7 files changed, 339 insertions(+), 126 deletions(-)
--
2.35.1
From: Trond Myklebust <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
---
include/linux/nfs_fs.h | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 72a732a5103c..6e10725887d1 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -363,7 +363,7 @@ static inline void nfs_mark_for_revalidate(struct inode *inode)
spin_unlock(&inode->i_lock);
}
-static inline int nfs_server_capable(struct inode *inode, int cap)
+static inline int nfs_server_capable(const struct inode *inode, int cap)
{
return NFS_SERVER(inode)->caps & cap;
}
@@ -587,12 +587,11 @@ extern struct nfs_commit_data *nfs_commitdata_alloc(bool never_fail);
extern void nfs_commit_free(struct nfs_commit_data *data);
bool nfs_commit_end(struct nfs_mds_commit_info *cinfo);
-static inline int
-nfs_have_writebacks(struct inode *inode)
+static inline bool nfs_have_writebacks(const struct inode *inode)
{
if (S_ISREG(inode->i_mode))
return atomic_long_read(&NFS_I(inode)->nrequests) != 0;
- return 0;
+ return false;
}
/*
--
2.35.1
From: Trond Myklebust <[email protected]>
Enable tracing of lookup revalidation failures.
Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/dir.c | 17 +++++------------
1 file changed, 5 insertions(+), 12 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 8b190c8e4a45..8e750ef34559 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1474,9 +1474,7 @@ nfs_lookup_revalidate_done(struct inode *dir, struct dentry *dentry,
{
switch (error) {
case 1:
- dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) is valid\n",
- __func__, dentry);
- return 1;
+ break;
case 0:
/*
* We can't d_drop the root of a disconnected tree:
@@ -1485,13 +1483,10 @@ nfs_lookup_revalidate_done(struct inode *dir, struct dentry *dentry,
* inodes on unmount and further oopses.
*/
if (inode && IS_ROOT(dentry))
- return 1;
- dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) is invalid\n",
- __func__, dentry);
- return 0;
+ error = 1;
+ break;
}
- dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) lookup returned error %d\n",
- __func__, dentry, error);
+ trace_nfs_lookup_revalidate_exit(dir, dentry, 0, error);
return error;
}
@@ -1623,9 +1618,7 @@ nfs_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
goto out_bad;
trace_nfs_lookup_revalidate_enter(dir, dentry, flags);
- error = nfs_lookup_revalidate_dentry(dir, dentry, inode);
- trace_nfs_lookup_revalidate_exit(dir, dentry, flags, error);
- return error;
+ return nfs_lookup_revalidate_dentry(dir, dentry, inode);
out_valid:
return nfs_lookup_revalidate_done(dir, dentry, inode, 1);
out_bad:
--
2.35.1