Add FUNCTION FLUSH command to flush all functions (#9936)

Added `FUNCTION FLUSH` command. The new sub-command allows delete all the functions.
An optional `[SYNC|ASYNC]` argument can be given to control whether or not to flush the
functions synchronously or asynchronously. if not given the default flush mode is chosen by
`lazyfree-lazy-user-flush` configuration values.

Add the missing `functions.tcl` test to the list of tests that are executed in test_helper.tcl,
and call FUNCTION FLUSH in between servers in external mode

1 files changed, 20 insertions, 0 deletions

diff --git a/src/lazyfree.c b/src/lazyfree.c
index 6127abe77..1cc521cbd 100644
--- a/src/lazyfree.c
+++ b/src/lazyfree.c
@@ -1,6 +1,7 @@
 #include "server.h"
 #include "bio.h"
 #include "atomicvar.h"
+#include "functions.h"
 
 static redisAtomic size_t lazyfree_objects = 0;
 static redisAtomic size_t lazyfreed_objects = 0;
@@ -46,6 +47,15 @@ void lazyFreeLuaScripts(void *args[]) {
     atomicIncr(lazyfreed_objects,len);
 }
 
+/* Release the functions ctx. */
+void lazyFreeFunctionsCtx(void *args[]) {
+    functionsCtx *f_ctx = args[0];
+    size_t len = functionsLen(f_ctx);
+    functionsCtxFree(f_ctx);
+    atomicDecr(lazyfree_objects,len);
+    atomicIncr(lazyfreed_objects,len);
+}
+
 /* Release replication backlog referencing memory. */
 void lazyFreeReplicationBacklogRefMem(void *args[]) {
     list *blocks = args[0];
@@ -193,6 +203,16 @@ void freeLuaScriptsAsync(dict *lua_scripts) {
     }
 }
 
+/* Free functions ctx, if the functions ctx contains enough functions, free it in async way. */
+void freeFunctionsAsync(functionsCtx *f_ctx) {
+    if (functionsLen(f_ctx) > LAZYFREE_THRESHOLD) {
+        atomicIncr(lazyfree_objects,functionsLen(f_ctx));
+        bioCreateLazyFreeJob(lazyFreeFunctionsCtx,1,f_ctx);
+    } else {
+        functionsCtxFree(f_ctx);
+    }
+}
+
 /* Free replication backlog referencing buffer blocks and rax index. */
 void freeReplicationBacklogRefMemAsync(list *blocks, rax *index) {
     if (listLength(blocks) > LAZYFREE_THRESHOLD ||