perf/x86/intel/uncore: Add alias PMU name

A perf PMU may have two PMU names. For example, Intel Sapphire Rapids
server supports the discovery mechanism. Without the platform-specific
support, an uncore PMU is named by a type ID plus a box ID, e.g.,
uncore_type_0_0, because the real name of the uncore PMU cannot be
retrieved from the discovery table. With the platform-specific support
later, perf has the mapping information from a type ID to a specific
uncore unit. Just like the previous platforms, the uncore PMU is named
by the real PMU name, e.g., uncore_cha_0. The user scripts which work
well with the old numeric name may not work anymore.

Add a new attribute "alias" to indicate the old numeric name. The
following userspace perf tool patch will handle both names. The user
scripts should work properly with the updated perf tool.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Link: https://lore.kernel.org/r/1625087320-194204-13-git-send-email-kan.liang@linux.intel.com

1 files changed, 27 insertions, 1 deletions

diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
index 1b9ab8ed2523..d0d02e048254 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -5587,6 +5587,26 @@ static const struct attribute_group spr_uncore_chabox_format_group = {
 	.attrs = spr_uncore_cha_formats_attr,
 };
 
+static ssize_t alias_show(struct device *dev,
+			  struct device_attribute *attr,
+			  char *buf)
+{
+	struct intel_uncore_pmu *pmu = dev_to_uncore_pmu(dev);
+	char pmu_name[UNCORE_PMU_NAME_LEN];
+
+	uncore_get_alias_name(pmu_name, pmu);
+	return sysfs_emit(buf, "%s\n", pmu_name);
+}
+
+static DEVICE_ATTR_RO(alias);
+
+static struct attribute *uncore_alias_attrs[] = {
+	&dev_attr_alias.attr,
+	NULL
+};
+
+ATTRIBUTE_GROUPS(uncore_alias);
+
 static struct intel_uncore_type spr_uncore_chabox = {
 	.name			= "cha",
 	.event_mask		= SPR_CHA_PMON_EVENT_MASK,
@@ -5594,6 +5614,7 @@ static struct intel_uncore_type spr_uncore_chabox = {
 	.num_shared_regs	= 1,
 	.ops			= &spr_uncore_chabox_ops,
 	.format_group		= &spr_uncore_chabox_format_group,
+	.attr_update		= uncore_alias_groups,
 };
 
 static struct intel_uncore_type spr_uncore_iio = {
@@ -5601,6 +5622,7 @@ static struct intel_uncore_type spr_uncore_iio = {
 	.event_mask		= SNBEP_PMON_RAW_EVENT_MASK,
 	.event_mask_ext		= SNR_IIO_PMON_RAW_EVENT_MASK_EXT,
 	.format_group		= &snr_uncore_iio_format_group,
+	.attr_update		= uncore_alias_groups,
 };
 
 static struct attribute *spr_uncore_raw_formats_attr[] = {
@@ -5620,7 +5642,8 @@ static const struct attribute_group spr_uncore_raw_format_group = {
 #define SPR_UNCORE_COMMON_FORMAT()				\
 	.event_mask		= SNBEP_PMON_RAW_EVENT_MASK,	\
 	.event_mask_ext		= SPR_RAW_EVENT_MASK_EXT,	\
-	.format_group		= &spr_uncore_raw_format_group
+	.format_group		= &spr_uncore_raw_format_group,	\
+	.attr_update		= uncore_alias_groups
 
 static struct intel_uncore_type spr_uncore_irp = {
 	SPR_UNCORE_COMMON_FORMAT(),
@@ -5635,6 +5658,7 @@ static struct intel_uncore_type spr_uncore_m2pcie = {
 
 static struct intel_uncore_type spr_uncore_pcu = {
 	.name			= "pcu",
+	.attr_update		= uncore_alias_groups,
 };
 
 static void spr_uncore_mmio_enable_event(struct intel_uncore_box *box,
@@ -5760,6 +5784,8 @@ static void uncore_type_customized_copy(struct intel_uncore_type *to_type,
 		to_type->event_descs = from_type->event_descs;
 	if (from_type->format_group)
 		to_type->format_group = from_type->format_group;
+	if (from_type->attr_update)
+		to_type->attr_update = from_type->attr_update;
 }
 
 static struct intel_uncore_type **