From: Thomas Tai <thomas.tai@oracle.com>
Date: Fri, 2 Sep 2016 19:18:19 +0000 (-0700)
Subject: sparc64: Fixes NUMA node cpulist sysfs file in single NUMA node case.
X-Git-Tag: v4.1.12-92~30^2~3
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=fdf8e9c846df76995f80e79cdc48a8ee7ad45a57;p=users%2Fjedix%2Flinux-maple.git

sparc64: Fixes NUMA node cpulist sysfs file in single NUMA node case.

Forward port 23175351 to UEK4

The sysfs file /sys/devices/system/node/node0/cpulist is incorrect in the
single node case on sun4v machines as the machine description record in this
case does not contain any NUMA information. A default list from 0 to NR_CPUS
was used prior. This file is read by utilities such as 'numactl --hardware'
and lscpu to show CPU-to-node assignment.

In order to fix this issue, the numa_cpumask_lookup_table is cleared at
bootup. Whenever an extra cpu is bringup via __cpu_up, the corresponding
cpu mask is set in the numa_cpumask_lookup_table.

Orabug: 24500614
Orabug: 22546851

Signed-off-by: Chris Hyser <chris.hyser@oracle.com>
Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
---

diff --git a/arch/sparc/kernel/cpumap.h b/arch/sparc/kernel/cpumap.h
index 9dac398c434a4..e6173aaccbc70 100644
--- a/arch/sparc/kernel/cpumap.h
+++ b/arch/sparc/kernel/cpumap.h
@@ -13,4 +13,6 @@ static inline int map_to_cpu(unsigned int index)
 }
 #endif
 
+void sparc64_update_numa_mask(unsigned int cpu);
+
 #endif
diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c
index c4b6221d0f206..6263c03ab2a5f 100644
--- a/arch/sparc/kernel/smp_64.c
+++ b/arch/sparc/kernel/smp_64.c
@@ -1315,6 +1315,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *tidle)
 			if (tlb_type != hypervisor)
 				smp_synchronize_one_tick(cpu);
 			cpu_map_rebuild();
+			sparc64_update_numa_mask(cpu);
 		}
 	}
 	return ret;
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index c28abb62367c7..2fde60da480a0 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -1266,7 +1266,10 @@ static void init_node_masks_nonnuma(void)
 	for (i = 0; i < NR_CPUS; i++)
 		numa_cpu_lookup_table[i] = 0;
 
-	cpumask_setall(&numa_cpumask_lookup_table[0]);
+	/* Add current cpu into numa_cpumask_lookup_table[0],
+	 * the rest of the numa cpumask will be set in __cpu_up().
+	 */
+	cpumask_set_cpu(smp_processor_id(), &numa_cpumask_lookup_table[0]);
 #endif
 }
 
@@ -1831,6 +1834,13 @@ static int __init bootmem_init_numa(void)
 	return err;
 }
 
+void sparc64_update_numa_mask(unsigned int cpu)
+{
+	if (num_node_masks > 1)
+		return;
+
+	cpumask_set_cpu(cpu, &numa_cpumask_lookup_table[0]);
+}
 #else
 
 static int bootmem_init_numa(void)
@@ -1838,6 +1848,10 @@ static int bootmem_init_numa(void)
 	return -1;
 }
 
+void sparc64_update_numa_mask(unsigned int cpu)
+{
+}
+
 #endif
 
 static void __init bootmem_init_nonnuma(void)