Re: [RFC PATCH v2 05/20] tracing/filters: Optimise cpumask vs cpumask filtering when user mask is a single CPU
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2023-07-29 19:35:02
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On Thu, 20 Jul 2023 17:30:41 +0100 Valentin Schneider [off-list ref] wrote:
/* Move along */
i++;
+
+ /*
+ * Optimisation: if the user-provided mask has a weight of one
+ * then we can treat it as a scalar input.
+ */
+ single = cpumask_weight(pred->mask) == 1;
+ if (single && field->filter_type == FILTER_CPUMASK) {
+ pred->val = cpumask_first(pred->mask);
+ kfree(pred->mask);Don't we need: pred->mask = NULL; here, or the free_predicate() will cause a double free? -- Steve
+ } +