jsval and Garbage Collection

[Masquerade]

My JSNative functions often call many other JSAPI and obtain many
jsval - more than the # of argv elements. So I cannot use the argv
as the sole rooted storage for my jsval. I am not sure if this is a
correct approach to get more rooted tmp storage:

static jsval * getJsvalTmp(JSContext *cx) {
static const int jsvalTmpLen=5;
static jsval jsvalTmp[jsvalTmpLen];// static var initialized only
when function first called.
static bool rooted=false;
if (!rooted) {
rooted=true;
for (int i=0; i<jsvalTmpLen; i++) {
jsvalTmp[i]=JSVAL_VOID;
JS_AddValueRoot(cx, &jsvalTmp[i]);
}
}
return jsvalTmp;
}

void some_other_function() {
jsval* rootedTmp=getJsvalTmp(cx) {
rootedTmp[0]= OBJECT_TO_JSVAL(..);
rootedTmp[1]= STRING_TO_JSVAL(...);
....
// reuse the tmp rooted jsval, would this cause the previous
JSObject/JSString gc'ed?
rootedTmp[0]= OBJECT_TO_JSVAL(..);
rootedTmp[1]= STRING_TO_JSVAL(...);
}
My getJsvalTmp() creates a permanently rooted jsval array on the first
invocation and returns a pointer to it everytime I need some tmp
rooted jsval. They serves as a reusable rooted tmp jsval storage
shared by my functions within the compilation unit.

I am not sure if my understanding is correct: now my jsvalTmp array is
rooted and any JSObject/JSString it points to is rooted and won't be
gc'ed. If yes, do I need to explicitly remove these JSObject/JSString
if I assign another JSObject/JSString to my jsval array?

When will a JS_RemoveValueRoot call needed?