From d22c3e0088e85be8131f7a9283f759cdbb20726d Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Wed, 9 Sep 2026 11:29:53 +0200 Subject: selftests/ftrace: Fix unique symbol check in kprobe_non_uniq_symbol.tc The current regex also matches symbols in modules, which makes the test fail on s390 where name_show is present only once in the kernel, but also multiple times in modules: 000001b1401cdc20 t name_show 000001b0c05e6c40 t name_show [mdev] 000001b0c0495f30 t name_show [i2c_core] Fix this by changing the regular expression to only match the function name. Link: https://lore.kernel.org/all/20260909092954.2200558-1-svens@linux.ibm.com/ Fixes: 03b80ff8023a ("selftests/ftrace: Add new test case which checks non unique symbol") Signed-off-by: Sven Schnelle Reviewed-by: Steven Rostedt Signed-off-by: Masami Hiramatsu (Google) --- lib/union_find.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 lib/union_find.c (limited to 'lib/union_find.c') diff --git a/lib/union_find.c b/lib/union_find.c new file mode 100644 index 000000000..413b0f8ad --- /dev/null +++ b/lib/union_find.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0 +#include + +/** + * uf_find - Find the root of a node and perform path compression + * @node: the node to find the root of + * + * This function returns the root of the node by following the parent + * pointers. It also performs path compression, making the tree shallower. + * + * Returns the root node of the set containing node. + */ +struct uf_node *uf_find(struct uf_node *node) +{ + struct uf_node *parent; + + while (node->parent != node) { + parent = node->parent; + node->parent = parent->parent; + node = parent; + } + return node; +} + +/** + * uf_union - Merge two sets, using union by rank + * @node1: the first node + * @node2: the second node + * + * This function merges the sets containing node1 and node2, by comparing + * the ranks to keep the tree balanced. + */ +void uf_union(struct uf_node *node1, struct uf_node *node2) +{ + struct uf_node *root1 = uf_find(node1); + struct uf_node *root2 = uf_find(node2); + + if (root1 == root2) + return; + + if (root1->rank < root2->rank) { + root1->parent = root2; + } else if (root1->rank > root2->rank) { + root2->parent = root1; + } else { + root2->parent = root1; + root1->rank++; + } +} -- cgit v1.3.1