diff --git a/src/gausskernel/cbb/bbox/bbox_lib.cpp b/src/gausskernel/cbb/bbox/bbox_lib.cpp
index 41f522373..cdb2520e2 100644
--- a/src/gausskernel/cbb/bbox/bbox_lib.cpp
+++ b/src/gausskernel/cbb/bbox/bbox_lib.cpp
@@ -326,8 +326,14 @@ struct PIPE_ID* bbox_GetFreePid(void)
 }
 
 /*
- * Release the occupied pipeid
- */
+function name: bbox_PutPid
+description: Release the occupied pipe.
+arguments: A pointer of type struct PIPE_ID*.
+return value: void
+note: If the argument pointer is null, then there is no need to free the storage, the function ends.
+date: 2022/8/2
+contact tel: same
+*/
 void bbox_PutPid(struct PIPE_ID* pstPid)
 {
     struct PIPE_IDS* pstPids = NULL;
@@ -344,6 +350,17 @@ void bbox_PutPid(struct PIPE_ID* pstPid)
 /*
  * find available pipe id by file handle
  */
+/*
+function name: bbox_FindPid
+description: In all occupied pipes, the function search the flag pipe through compare all structure
+					array elements's member variable stPid's member variable iFd with the function 
+                    argument iFd, if they are equal, then return the addres of this array elements.
+arguments: An integer that indicates a file's file handle.
+return value: A pointer of type struct PIPE_ID* or NULL.
+note: none
+date: 2022/8/2
+contact tel: same
+*/
 struct PIPE_ID* bbox_FindPid(int iFd)
 {
     u32 i;