[tip: perf/core] perf/x86/intel/uncore: Clear attr_update properly

[tip-bot2 for Alexander Antonov]

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

Commit-ID:     6532783310e2b2f50dc13f46c49aa6546cb6e7a3
Gitweb:        https://git.kernel.org/tip/6532783310e2b2f50dc13f46c49aa6546cb6e7a3
Author:        Alexander Antonov <alexander.antonov@xxxxxxxxxxxxxxx>
AuthorDate:    Thu, 17 Nov 2022 12:28:25 
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Thu, 24 Nov 2022 11:09:20 +01:00

perf/x86/intel/uncore: Clear attr_update properly

Current clear_attr_update procedure in pmu_set_mapping() sets attr_update
field in NULL that is not correct because intel_uncore_type pmu types can
contain several groups in attr_update field. For example, SPR platform
already has uncore_alias_group to update and then UPI topology group will
be added in next patches.

Fix current behavior and clear attr_update group related to mapping only.

Fixes: bb42b3d39781 ("perf/x86/intel/uncore: Expose an Uncore unit to IIO PMON mapping")
Signed-off-by: Alexander Antonov <alexander.antonov@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20221117122833.3103580-4-alexander.antonov@xxxxxxxxxxxxxxx
---
 arch/x86/events/intel/uncore_snbep.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c
index d3323f1..0d06b56 100644
--- a/arch/x86/events/intel/uncore_snbep.c
+++ b/arch/x86/events/intel/uncore_snbep.c
@@ -3872,6 +3872,21 @@ static const struct attribute_group *skx_iio_attr_update[] = {
 	NULL,
 };
 
+static void pmu_clear_mapping_attr(const struct attribute_group **groups,
+				   struct attribute_group *ag)
+{
+	int i;
+
+	for (i = 0; groups[i]; i++) {
+		if (groups[i] == ag) {
+			for (i++; groups[i]; i++)
+				groups[i - 1] = groups[i];
+			groups[i - 1] = NULL;
+			break;
+		}
+	}
+}
+
 static int
 pmu_set_mapping(struct intel_uncore_type *type, struct attribute_group *ag,
 		ssize_t (*show)(struct device*, struct device_attribute*, char*),
@@ -3926,7 +3941,7 @@ clear_attrs:
 clear_topology:
 	pmu_free_topology(type);
 clear_attr_update:
-	type->attr_update = NULL;
+	pmu_clear_mapping_attr(type->attr_update, ag);
 	return ret;
 }