[tip: perf/core] perf/amd/ibs: Advertise zen4_ibs_extensions as pmu capability attribute

tip-bot2 for Ravi Bangoria
2022-05-11T19:47:11Z

The following commit has been merged into the perf/core branch of tip:

Commit-ID: 838de1d843fc9b6161e0e1c6308a8c027d08606d
Gitweb: https://git.kernel.org/tip/838de1d843fc9b6161e0e1c6308a8c027d08606d
Author: Ravi Bangoria <ravi.bangoria@amd.com>
AuthorDate: Mon, 09 May 2022 10:19:10 +05:30
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 11 May 2022 16:27:10 +02:00

perf/amd/ibs: Advertise zen4_ibs_extensions as pmu capability attribute

PMU driver can advertise certain feature via capability attribute('caps'
sysfs directory) which can be consumed by userspace tools like perf. Add
zen4_ibs_extensions capability attribute for IBS pmus. This attribute
will be enabled when CPUID_Fn8000001B_EAX[11] is set.

With patch on Zen4:

$ ls /sys/bus/event_source/devices/ibs_op/caps
zen4_ibs_extensions

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220509044914.1473-5-ravi.bangoria@amd.com
---
arch/x86/events/amd/ibs.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c
index 2dc8b7e..c251bc4 100644
--- a/arch/x86/events/amd/ibs.c
+++ b/arch/x86/events/amd/ibs.c
@@ -537,8 +537,14 @@ static struct attribute_group empty_format_group = {
.attrs = attrs_empty,
};

+static struct attribute_group empty_caps_group = {
+ .name = "caps",
+ .attrs = attrs_empty,
+};
+
static const struct attribute_group *empty_attr_groups[] = {
&empty_format_group,
+ &empty_caps_group,
NULL,
};

@@ -546,6 +552,7 @@ PMU_FORMAT_ATTR(rand_en, "config:57");
PMU_FORMAT_ATTR(cnt_ctl, "config:19");
PMU_EVENT_ATTR_STRING(l3missonly, fetch_l3missonly, "config:59");
PMU_EVENT_ATTR_STRING(l3missonly, op_l3missonly, "config:16");
+PMU_EVENT_ATTR_STRING(zen4_ibs_extensions, zen4_ibs_extensions, "1");

static umode_t
zen4_ibs_extensions_is_visible(struct kobject *kobj, struct attribute *attr, int i)
@@ -563,6 +570,11 @@ static struct attribute *fetch_l3missonly_attrs[] = {
NULL,
};

+static struct attribute *zen4_ibs_extensions_attrs[] = {
+ &zen4_ibs_extensions.attr.attr,
+ NULL,
+};
+
static struct attribute_group group_rand_en = {
.name = "format",
.attrs = rand_en_attrs,
@@ -574,13 +586,21 @@ static struct attribute_group group_fetch_l3missonly = {
.is_visible = zen4_ibs_extensions_is_visible,
};

+static struct attribute_group group_zen4_ibs_extensions = {
+ .name = "caps",
+ .attrs = zen4_ibs_extensions_attrs,
+ .is_visible = zen4_ibs_extensions_is_visible,
+};
+
static const struct attribute_group *fetch_attr_groups[] = {
&group_rand_en,
+ &empty_caps_group,
NULL,
};

static const struct attribute_group *fetch_attr_update[] = {
&group_fetch_l3missonly,
+ &group_zen4_ibs_extensions,
NULL,
};

@@ -615,6 +635,7 @@ static struct attribute_group group_op_l3missonly = {
static const struct attribute_group *op_attr_update[] = {
&group_cnt_ctl,
&group_op_l3missonly,
+ &group_zen4_ibs_extensions,
NULL,
};