cephfs-journal-tool: add usage help info for header set <field>

Signed-off-by: dongdong tao <tdd21151186@gmail.com>

diff --git a/src/tools/cephfs/JournalTool.cc b/src/tools/cephfs/JournalTool.cc
index d49bedd8ecb28078476ae095919c9904ab35f882..d134769f8b2cfe38fabfb4f225c32caf6bafc2e8 100644 (file)
--- a/src/tools/cephfs/JournalTool.cc
+++ b/src/tools/cephfs/JournalTool.cc
@@ -49,6 +49,7 @@ void JournalTool::usage()
     << "      export <path>\n"
     << "      reset [--force]\n"
     << "  cephfs-journal-tool [options] header <get|set <field> <value>\n"
+    << "    <field>: [trimmed_pos|expire_pos|write_pos|pool_id]"
     << "  cephfs-journal-tool [options] event <effect> <selector> <output> [special options]\n"
     << "    <selector>:\n"
     << "      --range=<start>..<end>\n"