ctf: notif-iter: avoid reallocation in stack

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>

diff --git a/plugins/ctf/common/notif-iter/notif-iter.c b/plugins/ctf/common/notif-iter/notif-iter.c
index 4f295a4d31acc6665c6ddd060eb0733ed11f3d2e..4ab01c4ea1b501a99944498511dc4edacba8f6b0 100644 (file)
--- a/plugins/ctf/common/notif-iter/notif-iter.c
+++ b/plugins/ctf/common/notif-iter/notif-iter.c
@@ -64,8 +64,11 @@ struct stack_entry {
 
 /* Visit stack */
 struct stack {
-       /* Entries (struct stack_entry *) (top is last element) */
-       GPtrArray *entries;
+       /* Entries (struct stack_entry) */
+       GArray *entries;
+
+       /* Number of active entries */
+       size_t size;
 };
 
 /* State */
@@ -330,12 +333,6 @@ static
 enum bt_btr_status btr_timestamp_end_cb(void *value,
                struct bt_field_type *type, void *data);
 
-static
-void stack_entry_free_func(gpointer data)
-{
-       g_free(data);
-}
-
 static
 struct stack *stack_new(struct bt_notif_iter *notit)
 {
@@ -347,9 +344,9 @@ struct stack *stack_new(struct bt_notif_iter *notit)
                goto error;
        }
 
-       stack->entries = g_ptr_array_new_with_free_func(stack_entry_free_func);
+       stack->entries = g_array_new(FALSE, TRUE, sizeof(struct stack_entry));
        if (!stack->entries) {
-               BT_LOGE_STR("Failed to allocate a GPtrArray.");
+               BT_LOGE_STR("Failed to allocate a GArray.");
                goto error;
        }
 
@@ -366,41 +363,41 @@ void stack_destroy(struct stack *stack)
 {
        BT_ASSERT(stack);
        BT_LOGD("Destroying stack: addr=%p", stack);
-       g_ptr_array_free(stack->entries, TRUE);
+
+       if (stack->entries) {
+               g_array_free(stack->entries, TRUE);
+       }
+
        g_free(stack);
 }
 
 static
 int stack_push(struct stack *stack, struct bt_field *base)
 {
-       int ret = 0;
        struct stack_entry *entry;
 
        BT_ASSERT(stack);
        BT_ASSERT(base);
        BT_LOGV("Pushing base field on stack: stack-addr=%p, "
-               "stack-size-before=%u, stack-size-after=%u",
-               stack, stack->entries->len, stack->entries->len + 1);
-       entry = g_new0(struct stack_entry, 1);
-       if (!entry) {
-               BT_LOGE_STR("Failed to allocate one stack entry.");
-               ret = -1;
-               goto end;
+               "stack-size-before=%zu, stack-size-after=%zu",
+               stack, stack->size, stack->size + 1);
+
+       if (stack->entries->len == stack->size) {
+               g_array_set_size(stack->entries, stack->size + 1);
        }
 
+       entry = &g_array_index(stack->entries, struct stack_entry, stack->size);
        entry->base = base;
-       g_ptr_array_add(stack->entries, entry);
-
-end:
-       return ret;
+       entry->index = 0;
+       stack->size++;
+       return 0;
 }
 
 static inline
 unsigned int stack_size(struct stack *stack)
 {
        BT_ASSERT(stack);
-
-       return stack->entries->len;
+       return stack->size;
 }
 
 static
@@ -409,9 +406,9 @@ void stack_pop(struct stack *stack)
        BT_ASSERT(stack);
        BT_ASSERT(stack_size(stack));
        BT_LOGV("Popping from stack: "
-               "stack-addr=%p, stack-size-before=%u, stack-size-after=%u",
-               stack, stack->entries->len, stack->entries->len - 1);
-       g_ptr_array_remove_index(stack->entries, stack->entries->len - 1);
+               "stack-addr=%p, stack-size-before=%zu, stack-size-after=%zu",
+               stack, stack->size, stack->size - 1);
+       stack->size--;
 }
 
 static inline
@@ -419,8 +416,8 @@ struct stack_entry *stack_top(struct stack *stack)
 {
        BT_ASSERT(stack);
        BT_ASSERT(stack_size(stack));
-
-       return g_ptr_array_index(stack->entries, stack->entries->len - 1);
+       return &g_array_index(stack->entries, struct stack_entry,
+               stack->size - 1);
 }
 
 static inline
@@ -433,14 +430,7 @@ static
 void stack_clear(struct stack *stack)
 {
        BT_ASSERT(stack);
-
-       if (!stack_empty(stack)) {
-               BT_LOGV("Clearing stack: stack-addr=%p, stack-size=%u",
-                       stack, stack->entries->len);
-               g_ptr_array_remove_range(stack->entries, 0, stack_size(stack));
-       }
-
-       BT_ASSERT(stack_empty(stack));
+       stack->size = 0;
 }
 
 static inline