From 14f4654cbd531d48651e005cf05907c14bddb193 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Thu, 2 Jul 2009 17:58:19 +0200 Subject: perf_counter tools: Create new chain_for_each_child() iterator Iterating through children of a node in the callchain tree shows something that may be quite confusing at a first glance. The head is the children field of the parent and the list nodes are in the brothers field of the children. This is because the childs are linked to the parent as a list of "brothers" using the "children" list of the parent as a head: --------------- | Parent (head) |------------------------------------- --------------- | | | children | | | ----------- ----------- | | 1st child |---brother---| 2nd child |---brother----- ----------- ----------- This makes the following strange pattern often occuring: list_for_each_entry(child, &parent->children, brothers) { // do something with children } Abstract it to chain_for_each_child() to factorize and simplify this pattern. Signed-off-by: Frederic Weisbecker Cc: Peter Zijlstra Cc: Mike Galbraith Cc: Paul Mackerras Cc: Anton Blanchard Cc: Arnaldo Carvalho de Melo LKML-Reference: <1246550301-8954-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar --- tools/perf/util/callchain.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c index 3dceabd9b5ef..3c4a91fea622 100644 --- a/tools/perf/util/callchain.c +++ b/tools/perf/util/callchain.c @@ -16,6 +16,9 @@ #include "callchain.h" +#define chain_for_each_child(child, parent) \ + list_for_each_entry(child, &parent->children, brothers) + static void rb_insert_callchain(struct rb_root *root, struct callchain_node *chain) @@ -46,7 +49,7 @@ void sort_chain_to_rbtree(struct rb_root *rb_root, struct callchain_node *node) { struct callchain_node *child; - list_for_each_entry(child, &node->children, brothers) + chain_for_each_child(child, node) sort_chain_to_rbtree(rb_root, child); if (node->hit) @@ -77,7 +80,7 @@ create_child(struct callchain_node *parent, bool inherit_children) list_splice(&parent->children, &new->children); INIT_LIST_HEAD(&parent->children); - list_for_each_entry(next, &new->children, brothers) + chain_for_each_child(next, new) next->parent = new; } list_add_tail(&new->brothers, &parent->children); @@ -173,7 +176,7 @@ __append_chain_children(struct callchain_node *root, struct ip_callchain *chain, struct callchain_node *rnode; /* lookup in childrens */ - list_for_each_entry(rnode, &root->children, brothers) { + chain_for_each_child(rnode, root) { unsigned int ret = __append_chain(rnode, chain, start, syms); if (!ret) -- cgit v1.2.3