Subject: [PATCH 2182/2944] Intel: perf/x86: Add is_visible attribute_group callback for base events

From: Jiri Olsa <[email-masked]>
Date: Thu, 22 Oct 2020 10:22:52 +0800

to #31064126

commit 3d5672735b2348f5b13679a27f90c0847d22125d upstream
Backport summary: backport to kernel 4.19.57 for ICX perf topdown support

We dont need to pre-filter out unsupported base events,
we can just use its group's is_visible function to do this.

Signed-off-by: Jiri Olsa <[email-masked]>
Signed-off-by: Peter Zijlstra (Intel) <[email-masked]>
Cc: Alexander Shishkin <[email-masked]>
Cc: Arnaldo Carvalho de Melo <[email-masked]>
Cc: Greg Kroah-Hartman <[email-masked]>
Cc: Linus Torvalds <[email-masked]>
Cc: Namhyung Kim <[email-masked]>
Cc: Peter Zijlstra <[email-masked]>
Cc: Thomas Gleixner <[email-masked]>
Link: https://lkml.kernel.org/r/[email-masked]
Signed-off-by: Ingo Molnar <[email-masked]>
Signed-off-by: Yunying Sun <[email-masked]>
Signed-off-by: Peng Wang <[email-masked]>
Reviewed-by: Artie Ding <[email-masked]>
---
 arch/x86/events/core.c | 53 ++++++++++++++------------------------------------
 1 file changed, 15 insertions(+), 38 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index ea2ab71..5e1d0ed 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -1647,42 +1647,6 @@ static void __init pmu_check_apic(void)
 	.attrs = NULL,
 };
 
-/*
- * Remove all undefined events (x86_pmu.event_map(id) == 0)
- * out of events_attr attributes.
- */
-static void __init filter_events(struct attribute **attrs)
-{
-	struct device_attribute *d;
-	struct perf_pmu_events_attr *pmu_attr;
-	int offset = 0;
-	int i, j;
-
-	for (i = 0; attrs[i]; i++) {
-		d = (struct device_attribute *)attrs[i];
-		pmu_attr = container_of(d, struct perf_pmu_events_attr, attr);
-		/* str trumps id */
-		if (pmu_attr->event_str)
-			continue;
-		if (x86_pmu.event_map(i + offset))
-			continue;
-
-		for (j = i; attrs[j]; j++)
-			attrs[j] = attrs[j + 1];
-
-		/* Check the shifted attr. */
-		i--;
-
-		/*
-		 * event_map() is index based, the attrs array is organized
-		 * by increasing event index. If we shift the events, then
-		 * we need to compensate for the event_map(), otherwise
-		 * we are looking up the wrong event in the map
-		 */
-		offset++;
-	}
-}
-
 /* Merge two pointer arrays */
 __init struct attribute **merge_attr(struct attribute **a, struct attribute **b)
 {
@@ -1773,9 +1737,24 @@ ssize_t events_ht_sysfs_show(struct device *dev, struct device_attribute *attr,
 	NULL,
 };
 
+/*
+ * Remove all undefined events (x86_pmu.event_map(id) == 0)
+ * out of events_attr attributes.
+ */
+static umode_t
+is_visible(struct kobject *kobj, struct attribute *attr, int idx)
+{
+	struct perf_pmu_events_attr *pmu_attr;
+
+	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr.attr);
+	/* str trumps id */
+	return pmu_attr->event_str || x86_pmu.event_map(idx) ? attr->mode : 0;
+}
+
 static struct attribute_group x86_pmu_events_group = {
 	.name = "events",
 	.attrs = events_attr,
+	.is_visible = is_visible,
 };
 
 ssize_t x86_event_sysfs_show(char *page, u64 config, u64 event)
@@ -1881,8 +1860,6 @@ static int __init init_hw_perf_events(void)
 
 	if (!x86_pmu.events_sysfs_show)
 		x86_pmu_events_group.attrs = &empty_attrs;
-	else
-		filter_events(x86_pmu_events_group.attrs);
 
 	if (x86_pmu.attrs) {
 		struct attribute **tmp;
-- 
1.8.3.1