s390/topology: add drawer scheduling domain level

The z13 machine added a fourth level to the cpu topology
information. The new top level is called drawer.

A drawer contains two books, which used to be the top level.

Adding this additional scheduling domain did show performance
improvements for some workloads of up to 8%, while there don't
seem to be any workloads impacted in a negative way.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 20 insertions, 5 deletions

diff --git a/arch/s390/numa/mode_emu.c b/arch/s390/numa/mode_emu.c
index 828d0695d0d4..fbc394e16b2c 100644
--- a/arch/s390/numa/mode_emu.c
+++ b/arch/s390/numa/mode_emu.c
@@ -34,7 +34,8 @@
 #define DIST_CORE	1
 #define DIST_MC		2
 #define DIST_BOOK	3
-#define DIST_MAX	4
+#define DIST_DRAWER	4
+#define DIST_MAX	5
 
 /* Node distance reported to common code */
 #define EMU_NODE_DIST	10
@@ -43,7 +44,7 @@
 #define NODE_ID_FREE	-1
 
 /* Different levels of toptree */
-enum toptree_level {CORE, MC, BOOK, NODE, TOPOLOGY};
+enum toptree_level {CORE, MC, BOOK, DRAWER, NODE, TOPOLOGY};
 
 /* The two toptree IDs */
 enum {TOPTREE_ID_PHYS, TOPTREE_ID_NUMA};
@@ -114,6 +115,14 @@ static int cores_free(struct toptree *tree)
  */
 static struct toptree *core_node(struct toptree *core)
 {
+	return core->parent->parent->parent->parent;
+}
+
+/*
+ * Return drawer of core
+ */
+static struct toptree *core_drawer(struct toptree *core)
+{
 	return core->parent->parent->parent;
 }
 
@@ -138,6 +147,8 @@ static struct toptree *core_mc(struct toptree *core)
  */
 static int dist_core_to_core(struct toptree *core1, struct toptree *core2)
 {
+	if (core_drawer(core1)->id != core_drawer(core2)->id)
+		return DIST_DRAWER;
 	if (core_book(core1)->id != core_book(core2)->id)
 		return DIST_BOOK;
 	if (core_mc(core1)->id != core_mc(core2)->id)
@@ -262,6 +273,8 @@ static void toptree_to_numa_first(struct toptree *numa, struct toptree *phys)
 	struct toptree *core;
 
 	/* Always try to move perfectly fitting structures first */
+	move_level_to_numa(numa, phys, DRAWER, true);
+	move_level_to_numa(numa, phys, DRAWER, false);
 	move_level_to_numa(numa, phys, BOOK, true);
 	move_level_to_numa(numa, phys, BOOK, false);
 	move_level_to_numa(numa, phys, MC, true);
@@ -335,7 +348,7 @@ static struct toptree *toptree_to_numa(struct toptree *phys)
  */
 static struct toptree *toptree_from_topology(void)
 {
-	struct toptree *phys, *node, *book, *mc, *core;
+	struct toptree *phys, *node, *drawer, *book, *mc, *core;
 	struct cpu_topology_s390 *top;
 	int cpu;
 
@@ -344,10 +357,11 @@ static struct toptree *toptree_from_topology(void)
 	for_each_online_cpu(cpu) {
 		top = &per_cpu(cpu_topology, cpu);
 		node = toptree_get_child(phys, 0);
-		book = toptree_get_child(node, top->book_id);
+		drawer = toptree_get_child(node, top->drawer_id);
+		book = toptree_get_child(drawer, top->book_id);
 		mc = toptree_get_child(book, top->socket_id);
 		core = toptree_get_child(mc, top->core_id);
-		if (!book || !mc || !core)
+		if (!drawer || !book || !mc || !core)
 			panic("NUMA emulation could not allocate memory");
 		cpumask_set_cpu(cpu, &core->mask);
 		toptree_update_mask(mc);
@@ -368,6 +382,7 @@ static void topology_add_core(struct toptree *core)
 		cpumask_copy(&top->thread_mask, &core->mask);
 		cpumask_copy(&top->core_mask, &core_mc(core)->mask);
 		cpumask_copy(&top->book_mask, &core_book(core)->mask);
+		cpumask_copy(&top->drawer_mask, &core_drawer(core)->mask);
 		cpumask_set_cpu(cpu, &node_to_cpumask_map[core_node(core)->id]);
 		top->node_id = core_node(core)->id;
 	}