Commit 6019ce07 authored by Chuck Lever's avatar Chuck Lever
Browse files

NFSD: Add a tracepoint to record directory entry encoding 



Enable watching the progress of directory encoding to capture the
timing of any issues with reading or encoding a directory. The
new tracepoint captures dirent encoding for all NFS versions.

For example, here's what a few NFSv4 directory entries might look
like:

nfsd-989   [002]   468.596265: nfsd_dirent:          fh_hash=0x5d162594 ino=2 name=.
nfsd-989   [002]   468.596267: nfsd_dirent:          fh_hash=0x5d162594 ino=1 name=..
nfsd-989   [002]   468.596299: nfsd_dirent:          fh_hash=0x5d162594 ino=3827 name=zlib.c
nfsd-989   [002]   468.596325: nfsd_dirent:          fh_hash=0x5d162594 ino=3811 name=xdiff
nfsd-989   [002]   468.596351: nfsd_dirent:          fh_hash=0x5d162594 ino=3810 name=xdiff-interface.h
nfsd-989   [002]   468.596377: nfsd_dirent:          fh_hash=0x5d162594 ino=3809 name=xdiff-interface.c

Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 1416f435

fs/nfsd/trace.h

+24 −0
Original line number Diff line number Diff line
@@ -391,6 +391,30 @@ DEFINE_EVENT(nfsd_err_class, nfsd_##name, \ 
DEFINE_NFSD_ERR_EVENT(read_err);

DEFINE_NFSD_ERR_EVENT(write_err);



TRACE_EVENT(nfsd_dirent,

	TP_PROTO(struct svc_fh *fhp,

		 u64 ino,

		 const char *name,

		 int namlen),

	TP_ARGS(fhp, ino, name, namlen),

	TP_STRUCT__entry(

		__field(u32, fh_hash)

		__field(u64, ino)

		__field(int, len)

		__dynamic_array(unsigned char, name, namlen)

	),

	TP_fast_assign(

		__entry->fh_hash = fhp ? knfsd_fh_hash(&fhp->fh_handle) : 0;

		__entry->ino = ino;

		__entry->len = namlen;

		memcpy(__get_str(name), name, namlen);

		__assign_str(name, name);

	),

	TP_printk("fh_hash=0x%08x ino=%llu name=%.*s",

		__entry->fh_hash, __entry->ino,

		__entry->len, __get_str(name))

)



#include "state.h"

#include "filecache.h"

#include "vfs.h"

fs/nfsd/vfs.c

+6 −3
Original line number Diff line number Diff line
@@ -1968,8 +1968,9 @@ static int nfsd_buffered_filldir(struct dir_context *ctx, const char *name, 
	return 0;

}



static __be32 nfsd_buffered_readdir(struct file *file, nfsd_filldir_t func,

				    struct readdir_cd *cdp, loff_t *offsetp)

static __be32 nfsd_buffered_readdir(struct file *file, struct svc_fh *fhp,

				    nfsd_filldir_t func, struct readdir_cd *cdp,

				    loff_t *offsetp)

{

	struct buffered_dirent *de;

	int host_err;
@@ -2015,6 +2016,8 @@ static __be32 nfsd_buffered_readdir(struct file *file, nfsd_filldir_t func, 
			if (cdp->err != nfs_ok)

				break;



			trace_nfsd_dirent(fhp, de->ino, de->name, de->namlen);



			reclen = ALIGN(sizeof(*de) + de->namlen,

				       sizeof(u64));

			size -= reclen;
@@ -2062,7 +2065,7 @@ nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp, 
		goto out_close;

	}



	err = nfsd_buffered_readdir(file, func, cdp, offsetp);

	err = nfsd_buffered_readdir(file, fhp, func, cdp, offsetp);



	if (err == nfserr_eof || err == nfserr_toosmall)

		err = nfs_ok; /* can still be found in ->err */