Generate a trace event whenever the NFS client modifies the size of
a file. These new events aid troubleshooting workloads that trigger
races around size updates.
There are four new trace points, all named nfs_size_something so
they are easy to grep for or enable as a group with a single glob.
Size updated on the server:
kworker/u24:10-194 [010] 369.939174: nfs_size_update: fileid=00:28:2 fhandle=0x36fbbe51 version=1752899344277980615 cursize=250471 newsize=172083
Server-side size update reported via NFSv3 WCC attributes:
fsx-1387 [006] 380.760686: nfs_size_wcc: fileid=00:28:2 fhandle=0x36fbbe51 version=1752899355909932456 cursize=146792 newsize=171216
File has been truncated locally:
fsx-1387 [007] 369.437421: nfs_size_truncate: fileid=00:28:2 fhandle=0x36fbbe51 version=1752899231200117272 cursize=215244 newsize=0
File has been extended locally:
fsx-1387 [007] 369.439213: nfs_size_grow: fileid=00:28:2 fhandle=0x36fbbe51 version=1752899343704248410 cursize=258048 newsize=262144
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
fs/nfs/inode.c | 9 +++------
fs/nfs/nfstrace.h | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
fs/nfs/write.c | 1 +
3 files changed, 54 insertions(+), 6 deletions(-)
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 853213b3a209..7994a3629ccb 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -666,6 +666,7 @@ static int nfs_vmtruncate(struct inode * inode, loff_t offset)
if (err)
goto out;
+ trace_nfs_size_truncate(inode, offset);
i_size_write(inode, offset);
/* Optimisation */
if (offset == 0)
@@ -1453,6 +1454,7 @@ static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
&& !nfs_have_writebacks(inode)) {
+ trace_nfs_size_wcc(inode, fattr->size);
i_size_write(inode, nfs_size_to_loff_t(fattr->size));
}
}
@@ -2095,16 +2097,11 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
/* Do we perhaps have any outstanding writes, or has
* the file grown beyond our last write? */
if (!nfs_have_writebacks(inode) || new_isize > cur_isize) {
+ trace_nfs_size_update(inode, new_isize);
i_size_write(inode, new_isize);
if (!have_writers)
invalid |= NFS_INO_INVALID_DATA;
}
- dprintk("NFS: isize change on server for file %s/%ld "
- "(%Ld to %Ld)\n",
- inode->i_sb->s_id,
- inode->i_ino,
- (long long)cur_isize,
- (long long)new_isize);
}
if (new_isize == 0 &&
!(fattr->valid & (NFS_ATTR_FATTR_SPACE_USED |
diff --git a/fs/nfs/nfstrace.h b/fs/nfs/nfstrace.h
index 4094e2856cf9..228bdf010eb6 100644
--- a/fs/nfs/nfstrace.h
+++ b/fs/nfs/nfstrace.h
@@ -231,6 +231,56 @@ TRACE_EVENT(nfs_access_exit,
)
);
+DECLARE_EVENT_CLASS(nfs_update_size_class,
+ TP_PROTO(
+ const struct inode *inode,
+ loff_t new_size
+ ),
+
+ TP_ARGS(inode, new_size),
+
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(u32, fhandle)
+ __field(u64, fileid)
+ __field(u64, version)
+ __field(loff_t, cur_size)
+ __field(loff_t, new_size)
+ ),
+
+ TP_fast_assign(
+ const struct nfs_inode *nfsi = NFS_I(inode);
+
+ __entry->dev = inode->i_sb->s_dev;
+ __entry->fhandle = nfs_fhandle_hash(&nfsi->fh);
+ __entry->fileid = nfsi->fileid;
+ __entry->version = inode_peek_iversion_raw(inode);
+ __entry->cur_size = i_size_read(inode);
+ __entry->new_size = new_size;
+ ),
+
+ TP_printk(
+ "fileid=%02x:%02x:%llu fhandle=0x%08x version=%llu cursize=%lld newsize=%lld",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ (unsigned long long)__entry->fileid,
+ __entry->fhandle, __entry->version,
+ __entry->cur_size, __entry->new_size
+ )
+);
+
+#define DEFINE_NFS_UPDATE_SIZE_EVENT(name) \
+ DEFINE_EVENT(nfs_update_size_class, nfs_size_##name, \
+ TP_PROTO( \
+ const struct inode *inode, \
+ loff_t new_size \
+ ), \
+ TP_ARGS(inode, new_size))
+
+DEFINE_NFS_UPDATE_SIZE_EVENT(truncate);
+DEFINE_NFS_UPDATE_SIZE_EVENT(wcc);
+DEFINE_NFS_UPDATE_SIZE_EVENT(update);
+DEFINE_NFS_UPDATE_SIZE_EVENT(grow);
+
#define show_lookup_flags(flags) \
__print_flags(flags, "|", \
{ LOOKUP_FOLLOW, "FOLLOW" }, \
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index eae9bf114041..1ded0d232ece 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -288,6 +288,7 @@ static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int c
end = page_file_offset(page) + ((loff_t)offset+count);
if (i_size >= end)
goto out;
+ trace_nfs_size_grow(inode, end);
i_size_write(inode, end);
NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE;
nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
