From 2b1a61f0a8c714c96277bf16a823a84bafa1397d Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Thu, 25 Dec 2008 13:39:23 +0100 Subject: [S390] cpu topology: introduce kernel parameter Introduce a topology=[on|off] kernel parameter which allows to switch cpu topology on/off. Default will be off, since it looks like that for some workloards this doesn't behave very well (on s390). Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/topology.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'arch/s390') diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c index 36faac50e77..71e6f56bfea 100644 --- a/arch/s390/kernel/topology.c +++ b/arch/s390/kernel/topology.c @@ -58,6 +58,7 @@ struct core_info { cpumask_t mask; }; +static int topology_enabled; static void topology_work_fn(struct work_struct *work); static struct tl_info *tl_info; static struct core_info core_info; @@ -78,7 +79,7 @@ cpumask_t cpu_coregroup_map(unsigned int cpu) cpumask_t mask; cpus_clear(mask); - if (!machine_has_topology) + if (!topology_enabled || !machine_has_topology) return cpu_possible_map; spin_lock_irqsave(&topology_lock, flags); while (core) { @@ -263,6 +264,15 @@ static void topology_interrupt(__u16 code) schedule_work(&topology_work); } +static int __init early_parse_topology(char *p) +{ + if (strncmp(p, "on", 2)) + return 0; + topology_enabled = 1; + return 0; +} +early_param("topology", early_parse_topology); + static int __init init_topology_update(void) { int rc; -- cgit v1.2.3