NFS: Add tracepoints for debugging NFS rename and sillyrename issues

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 146 insertions, 0 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index e41dec5cfbc9..dca7deb1609b 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1909,6 +1909,7 @@ int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
                  new_dentry->d_parent->d_name.name, new_dentry->d_name.name,
                  d_count(new_dentry));
 
+        trace_nfs_rename_enter(old_dir, old_dentry, new_dir, new_dentry);
         /*
          * For non-directories, check whether the target is busy and if so,
          * make a copy of the dentry and then do a silly-rename. If the
@@ -1955,6 +1956,8 @@ int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 out:
         if (rehash)
                 d_rehash(rehash);
+        trace_nfs_rename_exit(old_dir, old_dentry,
+                        new_dir, new_dentry, error);
         if (!error) {
                 if (new_inode != NULL)
                         nfs_drop_nlink(new_inode);
diff --git a/fs/nfs/nfstrace.h b/fs/nfs/nfstrace.h
index 58279063b9a1..a20f0d147cf2 100644
--- a/fs/nfs/nfstrace.h
+++ b/fs/nfs/nfstrace.h
@@ -512,6 +512,144 @@ DEFINE_NFS_DIRECTORY_EVENT_DONE(nfs_unlink_exit);
 DEFINE_NFS_DIRECTORY_EVENT(nfs_symlink_enter);
 DEFINE_NFS_DIRECTORY_EVENT_DONE(nfs_symlink_exit);
 
+DECLARE_EVENT_CLASS(nfs_rename_event,
+                TP_PROTO(
+                        const struct inode *old_dir,
+                        const struct dentry *old_dentry,
+                        const struct inode *new_dir,
+                        const struct dentry *new_dentry
+                ),
+
+                TP_ARGS(old_dir, old_dentry, new_dir, new_dentry),
+
+                TP_STRUCT__entry(
+                        __field(dev_t, dev)
+                        __field(u64, old_dir)
+                        __field(u64, new_dir)
+                        __string(old_name, old_dentry->d_name.name)
+                        __string(new_name, new_dentry->d_name.name)
+                ),
+
+                TP_fast_assign(
+                        __entry->dev = old_dir->i_sb->s_dev;
+                        __entry->old_dir = NFS_FILEID(old_dir);
+                        __entry->new_dir = NFS_FILEID(new_dir);
+                        __assign_str(old_name, old_dentry->d_name.name);
+                        __assign_str(new_name, new_dentry->d_name.name);
+                ),
+
+                TP_printk(
+                        "old_name=%02x:%02x:%llu/%s new_name=%02x:%02x:%llu/%s",
+                        MAJOR(__entry->dev), MINOR(__entry->dev),
+                        (unsigned long long)__entry->old_dir,
+                        __get_str(old_name),
+                        MAJOR(__entry->dev), MINOR(__entry->dev),
+                        (unsigned long long)__entry->new_dir,
+                        __get_str(new_name)
+                )
+);
+#define DEFINE_NFS_RENAME_EVENT(name) \
+        DEFINE_EVENT(nfs_rename_event, name, \
+                        TP_PROTO( \
+                                const struct inode *old_dir, \
+                                const struct dentry *old_dentry, \
+                                const struct inode *new_dir, \
+                                const struct dentry *new_dentry \
+                        ), \
+                        TP_ARGS(old_dir, old_dentry, new_dir, new_dentry))
+
+DECLARE_EVENT_CLASS(nfs_rename_event_done,
+                TP_PROTO(
+                        const struct inode *old_dir,
+                        const struct dentry *old_dentry,
+                        const struct inode *new_dir,
+                        const struct dentry *new_dentry,
+                        int error
+                ),
+
+                TP_ARGS(old_dir, old_dentry, new_dir, new_dentry, error),
+
+                TP_STRUCT__entry(
+                        __field(dev_t, dev)
+                        __field(int, error)
+                        __field(u64, old_dir)
+                        __string(old_name, old_dentry->d_name.name)
+                        __field(u64, new_dir)
+                        __string(new_name, new_dentry->d_name.name)
+                ),
+
+                TP_fast_assign(
+                        __entry->dev = old_dir->i_sb->s_dev;
+                        __entry->old_dir = NFS_FILEID(old_dir);
+                        __entry->new_dir = NFS_FILEID(new_dir);
+                        __entry->error = error;
+                        __assign_str(old_name, old_dentry->d_name.name);
+                        __assign_str(new_name, new_dentry->d_name.name);
+                ),
+
+                TP_printk(
+                        "error=%d old_name=%02x:%02x:%llu/%s "
+                        "new_name=%02x:%02x:%llu/%s",
+                        __entry->error,
+                        MAJOR(__entry->dev), MINOR(__entry->dev),
+                        (unsigned long long)__entry->old_dir,
+                        __get_str(old_name),
+                        MAJOR(__entry->dev), MINOR(__entry->dev),
+                        (unsigned long long)__entry->new_dir,
+                        __get_str(new_name)
+                )
+);
+#define DEFINE_NFS_RENAME_EVENT_DONE(name) \
+        DEFINE_EVENT(nfs_rename_event_done, name, \
+                        TP_PROTO( \
+                                const struct inode *old_dir, \
+                                const struct dentry *old_dentry, \
+                                const struct inode *new_dir, \
+                                const struct dentry *new_dentry, \
+                                int error \
+                        ), \
+                        TP_ARGS(old_dir, old_dentry, new_dir, \
+                                new_dentry, error))
+
+DEFINE_NFS_RENAME_EVENT(nfs_rename_enter);
+DEFINE_NFS_RENAME_EVENT_DONE(nfs_rename_exit);
+
+DEFINE_NFS_RENAME_EVENT_DONE(nfs_sillyrename_rename);
+
+TRACE_EVENT(nfs_sillyrename_unlink,
+                TP_PROTO(
+                        const struct nfs_unlinkdata *data,
+                        int error
+                ),
+
+                TP_ARGS(data, error),
+
+                TP_STRUCT__entry(
+                        __field(dev_t, dev)
+                        __field(int, error)
+                        __field(u64, dir)
+                        __dynamic_array(char, name, data->args.name.len + 1)
+                ),
+
+                TP_fast_assign(
+                        struct inode *dir = data->dir;
+                        size_t len = data->args.name.len;
+                        __entry->dev = dir->i_sb->s_dev;
+                        __entry->dir = NFS_FILEID(dir);
+                        __entry->error = error;
+                        memcpy(__get_dynamic_array(name),
+                                data->args.name.name, len);
+                        ((char *)__get_dynamic_array(name))[len] = 0;
+                ),
+
+                TP_printk(
+                        "error=%d name=%02x:%02x:%llu/%s",
+                        __entry->error,
+                        MAJOR(__entry->dev), MINOR(__entry->dev),
+                        (unsigned long long)__entry->dir,
+                        __get_str(name)
+                )
+);
 #endif /* _TRACE_NFS_H */
 
 #undef TRACE_INCLUDE_PATH
diff --git a/fs/nfs/unlink.c b/fs/nfs/unlink.c
index 488fd162f75b..2c1485d18419 100644
--- a/fs/nfs/unlink.c
+++ b/fs/nfs/unlink.c
@@ -20,6 +20,8 @@
 #include "iostat.h"
 #include "delegation.h"
 
+#include "nfstrace.h"
+
 /**
  * nfs_free_unlinkdata - release data from a sillydelete operation.
  * @data: pointer to unlink structure.
@@ -77,6 +79,7 @@ static void nfs_async_unlink_done(struct rpc_task *task, void *calldata)
         struct nfs_unlinkdata *data = calldata;
         struct inode *dir = data->dir;
 
+        trace_nfs_sillyrename_unlink(data, task->tk_status);
         if (!NFS_PROTO(dir)->unlink_done(task, dir))
                 rpc_restart_call_prepare(task);
 }
@@ -336,6 +339,8 @@ static void nfs_async_rename_done(struct rpc_task *task, void *calldata)
         struct inode *new_dir = data->new_dir;
         struct dentry *old_dentry = data->old_dentry;
 
+        trace_nfs_sillyrename_rename(old_dir, old_dentry,
+                        new_dir, data->new_dentry, task->tk_status);
         if (!NFS_PROTO(old_dir)->rename_done(task, old_dir, new_dir)) {
                 rpc_restart_call_prepare(task);
                 return;