[PATCH v2 31/31] nfsd: convert dprintks in check_export() to tracepoints

[Jeff Layton]

Get rid of the dprintk messages in check_export(). Instead add new
tracepoints that show the terminal inode and the flags.

Signed-off-by: Jeff Layton <jlayton at kernel.org>
---
 fs/nfsd/export.c | 11 ++++++-----
 fs/nfsd/trace.h  | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+), 5 deletions(-)

diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index bc703cf58bfa210c7c57d49f22f15bc10d7cfc91..3cc336b953b38573966c43000f31cd341380837b 100644
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -435,31 +435,32 @@ static int check_export(const struct path *path, int *flags, unsigned char *uuid
 	if (!(inode->i_sb->s_type->fs_flags & FS_REQUIRES_DEV) &&
 	    !(*flags & NFSEXP_FSID) &&
 	    uuid == NULL) {
-		dprintk("exp_export: export of non-dev fs without fsid\n");
+		trace_nfsd_check_export_need_fsid(inode, *flags);
 		return -EINVAL;
 	}
 
 	if (!exportfs_can_decode_fh(inode->i_sb->s_export_op)) {
-		dprintk("exp_export: export of invalid fs type.\n");
+		trace_nfsd_check_export_invalid_fstype(inode, *flags);
 		return -EINVAL;
 	}
 
 	if (!(inode->i_sb->s_export_op->flags & EXPORT_OP_STABLE_HANDLES)) {
-		dprintk("%s: fs does not provide stable filehandles!\n", __func__);
+		trace_nfsd_check_export_no_stable_fh(inode, *flags);
 		return -EINVAL;
 	}
 
 	if (is_idmapped_mnt(path->mnt)) {
 		dprintk("exp_export: export of idmapped mounts not yet supported.\n");
+		trace_nfsd_check_export_idmapped(inode, *flags);
 		return -EINVAL;
 	}
 
 	if (inode->i_sb->s_export_op->flags & EXPORT_OP_NOSUBTREECHK &&
 	    !(*flags & NFSEXP_NOSUBTREECHECK)) {
-		dprintk("%s: %s does not support subtree checking!\n",
-			__func__, inode->i_sb->s_type->name);
+		trace_nfsd_check_export_subtree(inode, *flags);
 		return -EINVAL;
 	}
+	trace_nfsd_check_export_success(inode, *flags);
 	return 0;
 }
 
diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index 5ae2a611e57f4b4e51a4d9eb6e0fccb66ad8d288..e3f5fe1181b605b34cb70d53f32739c3ef9b82f6 100644
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -339,6 +339,58 @@ DEFINE_EVENT_CONDITION(nfsd_fh_err_class, nfsd_##name,	\
 DEFINE_NFSD_FH_ERR_EVENT(set_fh_dentry_badexport);
 DEFINE_NFSD_FH_ERR_EVENT(set_fh_dentry_badhandle);
 
+#define show_export_flags(val)						\
+	__print_flags(val, "|",						\
+		{ NFSEXP_READONLY,		"READONLY" },		\
+		{ NFSEXP_INSECURE_PORT,		"INSECURE" },		\
+		{ NFSEXP_ROOTSQUASH,		"ROOTSQUASH" },		\
+		{ NFSEXP_ALLSQUASH,		"ALLSQUASH" },		\
+		{ NFSEXP_ASYNC,			"ASYNC" },		\
+		{ NFSEXP_GATHERED_WRITES,	"GATHERED_WRITES" },	\
+		{ NFSEXP_NOREADDIRPLUS,		"NOREADDIRPLUS" },	\
+		{ NFSEXP_SECURITY_LABEL,	"SECURITY_LABEL" },	\
+		{ NFSEXP_NOHIDE,		"NOHIDE" },		\
+		{ NFSEXP_NOSUBTREECHECK,	"NOSUBTREECHECK" },	\
+		{ NFSEXP_NOAUTHNLM,		"NOAUTHNLM" },		\
+		{ NFSEXP_MSNFS,			"MSNFS" },		\
+		{ NFSEXP_FSID,			"FSID" },		\
+		{ NFSEXP_CROSSMOUNT,		"CROSSMOUNT" },		\
+		{ NFSEXP_NOACL,			"NOACL" },		\
+		{ NFSEXP_V4ROOT,		"V4ROOT" },		\
+		{ NFSEXP_PNFS,			"PNFS" })
+
+DECLARE_EVENT_CLASS(nfsd_check_export_class,
+	TP_PROTO(const struct inode *inode,
+		 int flags),
+	TP_ARGS(inode, flags),
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(ino_t, ino)
+		__field(int, flags)
+	),
+	TP_fast_assign(
+		__entry->dev = inode->i_sb->s_dev;
+		__entry->ino = inode->i_ino;
+		__entry->flags = flags;
+	),
+	TP_printk("dev=%u:%u:%lu flags=%s",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->ino, show_export_flags(__entry->flags))
+)
+
+#define DEFINE_NFSD_CHECK_EXPORT_EVENT(name)			\
+DEFINE_EVENT(nfsd_check_export_class, nfsd_check_export_##name,	\
+	TP_PROTO(const struct inode *inode,			\
+		 int flags),					\
+	TP_ARGS(inode, flags))
+
+DEFINE_NFSD_CHECK_EXPORT_EVENT(need_fsid);
+DEFINE_NFSD_CHECK_EXPORT_EVENT(invalid_fstype);
+DEFINE_NFSD_CHECK_EXPORT_EVENT(no_stable_fh);
+DEFINE_NFSD_CHECK_EXPORT_EVENT(idmapped);
+DEFINE_NFSD_CHECK_EXPORT_EVENT(subtree);
+DEFINE_NFSD_CHECK_EXPORT_EVENT(success);
+
 TRACE_EVENT(nfsd_exp_find_key,
 	TP_PROTO(const struct svc_expkey *key,
 		 int status),

-- 
2.52.0