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authorDapeng Mi <dapeng1.mi@linux.intel.com>2026-09-17 09:52:33 +0800
committerIngo Molnar <mingo@kernel.org>2026-09-22 11:37:46 +0200
commit0102c8c7fdfc4bd700971daff2b94470f4eafae4 (patch)
tree531306c2299f9a269f0a986e29f17ba972180104 /lib/union_find.c
downloadlinux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.tar.gz
linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.zip
perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted
DMR introduces Offmodule Response events in place of the legacy Offcore Response events, but it still exposes the inherited offcore_rsp PMU attribute for programming the corresponding MSR data. Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface matches the underlying event name and avoids user & tooling confusion. Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com
Diffstat (limited to 'lib/union_find.c')
-rw-r--r--lib/union_find.c49
1 files changed, 49 insertions, 0 deletions
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 <linux/union_find.h>
+
+/**
+ * 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++;
+ }
+}