[PATCH AUTOSEL 4.14 1/8] mips: cacheinfo: report shared CPU map

[Sasha Levin]

From: Vladimir Kondratiev <vladimir.kondratiev@xxxxxxxxx>

[ Upstream commit 3b1313eb32c499d46dc4c3e896d19d9564c879c4 ]

Report L1 caches as shared per core; L2 - per cluster.

This fixes "perf" that went crazy if shared_cpu_map attribute not
reported on sysfs, in form of

/sys/devices/system/cpu/cpu*/cache/index*/shared_cpu_list
/sys/devices/system/cpu/cpu*/cache/index*/shared_cpu_map

Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@xxxxxxxxx>
Signed-off-by: Paul Burton <paulburton@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: James Hogan <jhogan@xxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/mips/kernel/cacheinfo.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/arch/mips/kernel/cacheinfo.c b/arch/mips/kernel/cacheinfo.c
index 428ef2189203..3ea95568ece4 100644
--- a/arch/mips/kernel/cacheinfo.c
+++ b/arch/mips/kernel/cacheinfo.c
@@ -61,6 +61,25 @@ static int __init_cache_level(unsigned int cpu)
 	return 0;
 }
 
+static void fill_cpumask_siblings(int cpu, cpumask_t *cpu_map)
+{
+	int cpu1;
+
+	for_each_possible_cpu(cpu1)
+		if (cpus_are_siblings(cpu, cpu1))
+			cpumask_set_cpu(cpu1, cpu_map);
+}
+
+static void fill_cpumask_cluster(int cpu, cpumask_t *cpu_map)
+{
+	int cpu1;
+	int cluster = cpu_cluster(&cpu_data[cpu]);
+
+	for_each_possible_cpu(cpu1)
+		if (cpu_cluster(&cpu_data[cpu1]) == cluster)
+			cpumask_set_cpu(cpu1, cpu_map);
+}
+
 static int __populate_cache_leaves(unsigned int cpu)
 {
 	struct cpuinfo_mips *c = &current_cpu_data;
@@ -68,14 +87,20 @@ static int __populate_cache_leaves(unsigned int cpu)
 	struct cacheinfo *this_leaf = this_cpu_ci->info_list;
 
 	if (c->icache.waysize) {
+		/* L1 caches are per core */
+		fill_cpumask_siblings(cpu, &this_leaf->shared_cpu_map);
 		populate_cache(dcache, this_leaf, 1, CACHE_TYPE_DATA);
+		fill_cpumask_siblings(cpu, &this_leaf->shared_cpu_map);
 		populate_cache(icache, this_leaf, 1, CACHE_TYPE_INST);
 	} else {
 		populate_cache(dcache, this_leaf, 1, CACHE_TYPE_UNIFIED);
 	}
 
-	if (c->scache.waysize)
+	if (c->scache.waysize) {
+		/* L2 cache is per cluster */
+		fill_cpumask_cluster(cpu, &this_leaf->shared_cpu_map);
 		populate_cache(scache, this_leaf, 2, CACHE_TYPE_UNIFIED);
+	}
 
 	if (c->tcache.waysize)
 		populate_cache(tcache, this_leaf, 3, CACHE_TYPE_UNIFIED);
-- 
2.20.1