The append_chain() might return either result of match_chain() or other (error) code. But match_chain() can return any value in s64 type so it's hard to check the error case. Add new enum match_result and make match_chain() return non-negative values only so that we can check the error cases.
Cc: Frederic Weisbecker <[email protected]> Signed-off-by: Namhyung Kim <[email protected]> --- tools/perf/util/callchain.c | 44 ++++++++++++++++++++++++++++++-------------- 1 file changed, 30 insertions(+), 14 deletions(-) diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c index a82ea6f6fc0f..7139d438ee6d 100644 --- a/tools/perf/util/callchain.c +++ b/tools/perf/util/callchain.c @@ -475,16 +475,32 @@ add_child(struct callchain_node *parent, return new; } +enum match_result { + MATCH_ERROR = -1, + MATCH_EQ, + MATCH_LT, + MATCH_GT, +}; + static s64 match_chain(struct callchain_cursor_node *node, struct callchain_list *cnode) { struct symbol *sym = node->sym; + u64 left, right; if (cnode->ms.sym && sym && - callchain_param.key == CCKEY_FUNCTION) - return cnode->ms.sym->start - sym->start; - else - return cnode->ip - node->ip; + callchain_param.key == CCKEY_FUNCTION) { + left = cnode->ms.sym->start; + right = sym->start; + } else { + left = cnode->ip; + right = node->ip; + } + + if (left == right) + return MATCH_EQ; + + return left > right ? MATCH_GT : MATCH_LT; } /* @@ -562,7 +578,7 @@ split_add_child(struct callchain_node *parent, } } -static int +static enum match_result append_chain(struct callchain_node *root, struct callchain_cursor *cursor, u64 period); @@ -583,17 +599,17 @@ append_chain_children(struct callchain_node *root, /* lookup in childrens */ while (*p) { - s64 ret; + enum match_result ret; parent = *p; rnode = rb_entry(parent, struct callchain_node, rb_node_in); /* If at least first entry matches, rely to children */ ret = append_chain(rnode, cursor, period); - if (ret == 0) + if (ret == MATCH_EQ) goto inc_children_hit; - if (ret < 0) + if (ret == MATCH_LT) p = &parent->rb_left; else p = &parent->rb_right; @@ -611,7 +627,7 @@ inc_children_hit: root->children_count++; } -static int +static enum match_result append_chain(struct callchain_node *root, struct callchain_cursor *cursor, u64 period) @@ -620,7 +636,7 @@ append_chain(struct callchain_node *root, u64 start = cursor->pos; bool found = false; u64 matches; - int cmp = 0; + enum match_result cmp = MATCH_ERROR; /* * Lookup in the current node @@ -646,7 +662,7 @@ append_chain(struct callchain_node *root, /* matches not, relay no the parent */ if (!found) { - WARN_ONCE(!cmp, "Chain comparison error\n"); + WARN_ONCE(cmp == MATCH_ERROR, "Chain comparison error\n"); return cmp; } @@ -655,20 +671,20 @@ append_chain(struct callchain_node *root, /* we match only a part of the node. Split it and add the new chain */ if (matches < root->val_nr) { split_add_child(root, cursor, cnode, start, matches, period); - return 0; + return MATCH_EQ; } /* we match 100% of the path, increment the hit */ if (matches == root->val_nr && cursor->pos == cursor->nr) { root->hit += period; root->count++; - return 0; + return MATCH_EQ; } /* We match the node and still have a part remaining */ append_chain_children(root, cursor, period); - return 0; + return MATCH_EQ; } int callchain_append(struct callchain_root *root, -- 2.6.4
