diff options
Diffstat (limited to 'arch/s390/kernel/topology.c')
| -rw-r--r-- | arch/s390/kernel/topology.c | 148 |
1 files changed, 135 insertions, 13 deletions
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c index bb47c92476f0..ed0bdd220e1a 100644 --- a/arch/s390/kernel/topology.c +++ b/arch/s390/kernel/topology.c @@ -8,6 +8,8 @@ #include <linux/workqueue.h> #include <linux/bootmem.h> +#include <linux/uaccess.h> +#include <linux/sysctl.h> #include <linux/cpuset.h> #include <linux/device.h> #include <linux/export.h> @@ -29,12 +31,20 @@ #define PTF_VERTICAL (1UL) #define PTF_CHECK (2UL) +enum { + TOPOLOGY_MODE_HW, + TOPOLOGY_MODE_SINGLE, + TOPOLOGY_MODE_PACKAGE, + TOPOLOGY_MODE_UNINITIALIZED +}; + struct mask_info { struct mask_info *next; unsigned char id; cpumask_t mask; }; +static int topology_mode = TOPOLOGY_MODE_UNINITIALIZED; static void set_topology_timer(void); static void topology_work_fn(struct work_struct *work); static struct sysinfo_15_1_x *tl_info; @@ -59,11 +69,26 @@ static cpumask_t cpu_group_map(struct mask_info *info, unsigned int cpu) cpumask_t mask; cpumask_copy(&mask, cpumask_of(cpu)); - if (!MACHINE_HAS_TOPOLOGY) - return mask; - for (; info; info = info->next) { - if (cpumask_test_cpu(cpu, &info->mask)) - return info->mask; + switch (topology_mode) { + case TOPOLOGY_MODE_HW: + while (info) { + if (cpumask_test_cpu(cpu, &info->mask)) { + mask = info->mask; + break; + } + info = info->next; + } + if (cpumask_empty(&mask)) + cpumask_copy(&mask, cpumask_of(cpu)); + break; + case TOPOLOGY_MODE_PACKAGE: + cpumask_copy(&mask, cpu_present_mask); + break; + default: + /* fallthrough */ + case TOPOLOGY_MODE_SINGLE: + cpumask_copy(&mask, cpumask_of(cpu)); + break; } return mask; } @@ -74,7 +99,7 @@ static cpumask_t cpu_thread_map(unsigned int cpu) int i; cpumask_copy(&mask, cpumask_of(cpu)); - if (!MACHINE_HAS_TOPOLOGY) + if (topology_mode != TOPOLOGY_MODE_HW) return mask; cpu -= cpu % (smp_cpu_mtid + 1); for (i = 0; i <= smp_cpu_mtid; i++) @@ -184,10 +209,8 @@ static void topology_update_polarization_simple(void) { int cpu; - mutex_lock(&smp_cpu_state_mutex); for_each_possible_cpu(cpu) smp_cpu_set_polarization(cpu, POLARIZATION_HRZ); - mutex_unlock(&smp_cpu_state_mutex); } static int ptf(unsigned long fc) @@ -223,7 +246,7 @@ int topology_set_cpu_management(int fc) static void update_cpu_masks(void) { struct cpu_topology_s390 *topo; - int cpu; + int cpu, id; for_each_possible_cpu(cpu) { topo = &cpu_topology[cpu]; @@ -231,12 +254,13 @@ static void update_cpu_masks(void) topo->core_mask = cpu_group_map(&socket_info, cpu); topo->book_mask = cpu_group_map(&book_info, cpu); topo->drawer_mask = cpu_group_map(&drawer_info, cpu); - if (!MACHINE_HAS_TOPOLOGY) { + if (topology_mode != TOPOLOGY_MODE_HW) { + id = topology_mode == TOPOLOGY_MODE_PACKAGE ? 0 : cpu; topo->thread_id = cpu; topo->core_id = cpu; - topo->socket_id = cpu; - topo->book_id = cpu; - topo->drawer_id = cpu; + topo->socket_id = id; + topo->book_id = id; + topo->drawer_id = id; if (cpu_present(cpu)) cpumask_set_cpu(cpu, &cpus_with_topology); } @@ -254,6 +278,7 @@ static int __arch_update_cpu_topology(void) struct sysinfo_15_1_x *info = tl_info; int rc = 0; + mutex_lock(&smp_cpu_state_mutex); cpumask_clear(&cpus_with_topology); if (MACHINE_HAS_TOPOLOGY) { rc = 1; @@ -263,6 +288,7 @@ static int __arch_update_cpu_topology(void) update_cpu_masks(); if (!MACHINE_HAS_TOPOLOGY) topology_update_polarization_simple(); + mutex_unlock(&smp_cpu_state_mutex); return rc; } @@ -289,6 +315,11 @@ void topology_schedule_update(void) schedule_work(&topology_work); } +static void topology_flush_work(void) +{ + flush_work(&topology_work); +} + static void topology_timer_fn(unsigned long ignored) { if (ptf(PTF_CHECK)) @@ -459,6 +490,12 @@ void __init topology_init_early(void) struct sysinfo_15_1_x *info; set_sched_topology(s390_topology); + if (topology_mode == TOPOLOGY_MODE_UNINITIALIZED) { + if (MACHINE_HAS_TOPOLOGY) + topology_mode = TOPOLOGY_MODE_HW; + else + topology_mode = TOPOLOGY_MODE_SINGLE; + } if (!MACHINE_HAS_TOPOLOGY) goto out; tl_info = memblock_virt_alloc(PAGE_SIZE, PAGE_SIZE); @@ -474,12 +511,97 @@ out: __arch_update_cpu_topology(); } +static inline int topology_get_mode(int enabled) +{ + if (!enabled) + return TOPOLOGY_MODE_SINGLE; + return MACHINE_HAS_TOPOLOGY ? TOPOLOGY_MODE_HW : TOPOLOGY_MODE_PACKAGE; +} + +static inline int topology_is_enabled(void) +{ + return topology_mode != TOPOLOGY_MODE_SINGLE; +} + +static int __init topology_setup(char *str) +{ + bool enabled; + int rc; + + rc = kstrtobool(str, &enabled); + if (rc) + return rc; + topology_mode = topology_get_mode(enabled); + return 0; +} +early_param("topology", topology_setup); + +static int topology_ctl_handler(struct ctl_table *ctl, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + unsigned int len; + int new_mode; + char buf[2]; + + if (!*lenp || *ppos) { + *lenp = 0; + return 0; + } + if (!write) { + strncpy(buf, topology_is_enabled() ? "1\n" : "0\n", + ARRAY_SIZE(buf)); + len = strnlen(buf, ARRAY_SIZE(buf)); + if (len > *lenp) + len = *lenp; + if (copy_to_user(buffer, buf, len)) + return -EFAULT; + goto out; + } + len = *lenp; + if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len)) + return -EFAULT; + if (buf[0] != '0' && buf[0] != '1') + return -EINVAL; + mutex_lock(&smp_cpu_state_mutex); + new_mode = topology_get_mode(buf[0] == '1'); + if (topology_mode != new_mode) { + topology_mode = new_mode; + topology_schedule_update(); + } + mutex_unlock(&smp_cpu_state_mutex); + topology_flush_work(); +out: + *lenp = len; + *ppos += len; + return 0; +} + +static struct ctl_table topology_ctl_table[] = { + { + .procname = "topology", + .mode = 0644, + .proc_handler = topology_ctl_handler, + }, + { }, +}; + +static struct ctl_table topology_dir_table[] = { + { + .procname = "s390", + .maxlen = 0, + .mode = 0555, + .child = topology_ctl_table, + }, + { }, +}; + static int __init topology_init(void) { if (MACHINE_HAS_TOPOLOGY) set_topology_timer(); else topology_update_polarization_simple(); + register_sysctl_table(topology_dir_table); return device_create_file(cpu_subsys.dev_root, &dev_attr_dispatching); } device_initcall(topology_init); |