From 3a0c394fa2eafdb3be3da59920556071b2a20d0a Mon Sep 17 00:00:00 2001
From: Jan Polensky <japo@linux.ibm.com>
Date: Mon, 29 Sep 2025 12:58:52 +0200
Subject: [PATCH] libcpumf: Relocate ctr_in_list() for shared use
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Move ctr_in_list() from cpumf/lspai.c to a shared location to enable
reuse in other binaries that require counter list filtering.

Reviewed-by:  Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Jan Polensky <japo@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
---
 cpumf/lspai.c               | 28 ++--------------------------
 include/lib/libcpumf.h      | 15 +++++++++++++++
 libcpumf/libcpumf_support.c | 23 +++++++++++++++++++++++
 3 files changed, 40 insertions(+), 26 deletions(-)

diff --git a/cpumf/lspai.c b/cpumf/lspai.c
index 20a57fd4..8df91387 100644
--- a/cpumf/lspai.c
+++ b/cpumf/lspai.c
@@ -233,31 +233,6 @@ static int pai_ctrcmp(const void *p1, const void *p2)
 	return l->nr > r->nr ? 1 : -1;
 }
 
-/* Return true if the counter is in the ctrlist. An empty ctrlist
- * disables all counters.
- */
-static bool ctr_in_list(char *name)
-{
-	char *token;
-	char *list;
-
-	if (!ctrlist)		/* No --counters means all counters */
-		return true;
-
-	list = util_strdup(ctrlist);
-	token = strtok(list, ",");
-	while (token) {
-		if (strcmp(token, name) == 0) {
-			free(list);
-			return true;
-		}
-		token = strtok(NULL, ",");
-	}
-
-	free(list);
-	return false;
-}
-
 /* Read counter names and assigned event number from sysfs file tree.
  * Exit when sysfs directory can not be scanned.
  */
@@ -280,7 +255,8 @@ static void read_counternames(struct pai_node *node)
 		if (util_file_read_va(ctrpath, "event=%x", &ctr) == 1) {
 			snprintf(sname, sizeof(sname), "%c%ld",
 				 pai_type_char(node->type), ctr - node->base);
-			if (!ctr_in_list(sname) && !ctr_in_list(namelist[i]->d_name)) {
+			if (!ctr_in_list(sname, ctrlist) &&
+			    !ctr_in_list(namelist[i]->d_name, ctrlist)) {
 				/* Counter not listed in --counters option */
 				continue;
 			}
diff --git a/include/lib/libcpumf.h b/include/lib/libcpumf.h
index f960018d..faef0589 100644
--- a/include/lib/libcpumf.h
+++ b/include/lib/libcpumf.h
@@ -202,4 +202,19 @@ bool libcpumf_have_pai_nnpa(void);
 
 long perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu, int group_fd,
 		     unsigned long flags);
+
+/**
+ * Check if a counter name is present in a comma-separated list of counters.
+ *
+ * This function checks whether the given counter name appears in the
+ * provided list. If the list is NULL, the function assumes all counters
+ * are allowed and returns true.
+ *
+ * @param name      Name of the counter to search for
+ * @param ctrlist   Comma-separated list of counter names, or NULL
+ *
+ * @return          true if the counter is in the list or list is NULL
+ * @return          false otherwise
+ */
+bool ctr_in_list(char *name, char *ctrlist);
 #endif
diff --git a/libcpumf/libcpumf_support.c b/libcpumf/libcpumf_support.c
index a4f672c4..76e7065c 100644
--- a/libcpumf/libcpumf_support.c
+++ b/libcpumf/libcpumf_support.c
@@ -14,6 +14,7 @@
 
 #include "lib/libcpumf.h"
 #include "lib/util_path.h"
+#include "lib/util_libc.h"
 
 #define	SERVICELEVEL	"/proc/service_levels"
 
@@ -175,3 +176,25 @@ long perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu, int g
 {
 	return syscall(__NR_perf_event_open, hw_event, pid, cpu, group_fd, flags);
 }
+
+bool ctr_in_list(char *name, char *ctrlist)
+{
+	char *token;
+	char *list;
+
+	if (!ctrlist) /* No --counters means all counters */
+		return true;
+
+	list = util_strdup(ctrlist);
+	token = strtok(list, ",");
+	while (token) {
+		if (strcmp(token, name) == 0) {
+			free(list);
+			return true;
+		}
+		token = strtok(NULL, ",");
+	}
+
+	free(list);
+	return false;
+}