From 1887aa07b6765d345dd79f26017aa2d15d49d7af Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 22 Sep 2017 14:17:41 +0200 Subject: s390/topology: add detection of dedicated vs shared CPUs The topology information returned by STSI 15.x.x contains a flag if the CPUs of a topology-list are dedicated or shared. Make this information available if the machine provides topology information. Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/smp.c | 10 ++++++++-- arch/s390/kernel/topology.c | 43 ++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 50 insertions(+), 3 deletions(-) (limited to 'arch/s390/kernel') diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 1cee6753d47a..b9fc9b00d845 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -800,6 +800,8 @@ void __init smp_detect_cpus(void) */ static void smp_start_secondary(void *cpuvoid) { + int cpu = smp_processor_id(); + S390_lowcore.last_update_clock = get_tod_clock(); S390_lowcore.restart_stack = (unsigned long) restart_stack; S390_lowcore.restart_fn = (unsigned long) do_restart; @@ -813,8 +815,12 @@ static void smp_start_secondary(void *cpuvoid) init_cpu_timer(); vtime_init(); pfault_init(); - notify_cpu_starting(smp_processor_id()); - set_cpu_online(smp_processor_id(), true); + notify_cpu_starting(cpu); + if (topology_cpu_dedicated(cpu)) + set_cpu_flag(CIF_DEDICATED_CPU); + else + clear_cpu_flag(CIF_DEDICATED_CPU); + set_cpu_online(cpu, true); inc_irq_stat(CPU_RST); local_irq_enable(); cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c index ed0bdd220e1a..d49940fb43b1 100644 --- a/arch/s390/kernel/topology.c +++ b/arch/s390/kernel/topology.c @@ -133,6 +133,7 @@ static void add_cpus_to_mask(struct topology_core *tl_core, topo->socket_id = socket->id; topo->core_id = rcore; topo->thread_id = lcpu + i; + topo->dedicated = tl_core->d; cpumask_set_cpu(lcpu + i, &drawer->mask); cpumask_set_cpu(lcpu + i, &book->mask); cpumask_set_cpu(lcpu + i, &socket->mask); @@ -273,6 +274,14 @@ void store_topology(struct sysinfo_15_1_x *info) stsi(info, 15, 1, topology_mnest_limit()); } +static void __arch_update_dedicated_flag(void *arg) +{ + if (topology_cpu_dedicated(smp_processor_id())) + set_cpu_flag(CIF_DEDICATED_CPU); + else + clear_cpu_flag(CIF_DEDICATED_CPU); +} + static int __arch_update_cpu_topology(void) { struct sysinfo_15_1_x *info = tl_info; @@ -298,6 +307,7 @@ int arch_update_cpu_topology(void) int cpu, rc; rc = __arch_update_cpu_topology(); + on_each_cpu(__arch_update_dedicated_flag, NULL, 0); for_each_online_cpu(cpu) { dev = get_cpu_device(cpu); kobject_uevent(&dev->kobj, KOBJ_CHANGE); @@ -435,9 +445,39 @@ static struct attribute_group topology_cpu_attr_group = { .attrs = topology_cpu_attrs, }; +static ssize_t cpu_dedicated_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int cpu = dev->id; + ssize_t count; + + mutex_lock(&smp_cpu_state_mutex); + count = sprintf(buf, "%d\n", topology_cpu_dedicated(cpu)); + mutex_unlock(&smp_cpu_state_mutex); + return count; +} +static DEVICE_ATTR(dedicated, 0444, cpu_dedicated_show, NULL); + +static struct attribute *topology_extra_cpu_attrs[] = { + &dev_attr_dedicated.attr, + NULL, +}; + +static struct attribute_group topology_extra_cpu_attr_group = { + .attrs = topology_extra_cpu_attrs, +}; + int topology_cpu_init(struct cpu *cpu) { - return sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group); + int rc; + + rc = sysfs_create_group(&cpu->dev.kobj, &topology_cpu_attr_group); + if (rc || !MACHINE_HAS_TOPOLOGY) + return rc; + rc = sysfs_create_group(&cpu->dev.kobj, &topology_extra_cpu_attr_group); + if (rc) + sysfs_remove_group(&cpu->dev.kobj, &topology_cpu_attr_group); + return rc; } static const struct cpumask *cpu_thread_mask(int cpu) @@ -509,6 +549,7 @@ void __init topology_init_early(void) alloc_masks(info, &drawer_info, 3); out: __arch_update_cpu_topology(); + __arch_update_dedicated_flag(NULL); } static inline int topology_get_mode(int enabled) -- cgit v1.2.3