perf/x86: Use update attribute groups for caps

Using the new pmu::update_attrs attribute group for
"caps" directory.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190512155518.21468-7-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/events/core.c

@@ -1821,14 +1821,6 @@ static int __init init_hw_perf_events(void)
 
 	x86_pmu_format_group.attrs = x86_pmu.format_attrs;
 
-	if (x86_pmu.caps_attrs) {
-		struct attribute **tmp;
-
-		tmp = merge_attr(x86_pmu_caps_group.attrs, x86_pmu.caps_attrs);
-		if (!WARN_ON(!tmp))
-			x86_pmu_caps_group.attrs = tmp;
-	}
-
 	if (!x86_pmu.events_sysfs_show)
 		x86_pmu_events_group.attrs = &empty_attrs;
 

arch/x86/events/intel/core.c

@@ -4411,6 +4411,12 @@ pebs_is_visible(struct kobject *kobj, struct attribute *attr, int i)
 	return x86_pmu.pebs ? attr->mode : 0;
 }
 
+static umode_t
+lbr_is_visible(struct kobject *kobj, struct attribute *attr, int i)
+{
+	return x86_pmu.lbr_nr ? attr->mode : 0;
+}
+
 static struct attribute_group group_events_td  = {
 	.name = "events",
 };
@@ -4425,10 +4431,23 @@ static struct attribute_group group_events_tsx = {
 	.is_visible = tsx_is_visible,
 };
 
+static struct attribute_group group_caps_gen = {
+	.name  = "caps",
+	.attrs = intel_pmu_caps_attrs,
+};
+
+static struct attribute_group group_caps_lbr = {
+	.name       = "caps",
+	.attrs	    = lbr_attrs,
+	.is_visible = lbr_is_visible,
+};
+
 static const struct attribute_group *attr_update[] = {
 	&group_events_td,
 	&group_events_mem,
 	&group_events_tsx,
+	&group_caps_gen,
+	&group_caps_lbr,
 	NULL,
 };
 
@@ -5055,12 +5074,8 @@ __init int intel_pmu_init(void)
 			x86_pmu.lbr_nr = 0;
 	}
 
-	x86_pmu.caps_attrs = intel_pmu_caps_attrs;
-
-	if (x86_pmu.lbr_nr) {
-		x86_pmu.caps_attrs = merge_attr(x86_pmu.caps_attrs, lbr_attrs);
+	if (x86_pmu.lbr_nr)
 		pr_cont("%d-deep LBR, ", x86_pmu.lbr_nr);
-	}
 
 	/*
 	 * Access extra MSR may cause #GP under certain circumstances.

arch/x86/events/perf_event.h

@@ -631,7 +631,6 @@ struct x86_pmu {
 	int		attr_rdpmc_broken;
 	int		attr_rdpmc;
 	struct attribute **format_attrs;
-	struct attribute **caps_attrs;
 
 	ssize_t		(*events_sysfs_show)(char *page, u64 config);
 	const struct attribute_group **attr_update;