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author | Juri Lelli <juri.lelli@arm.com> | 2017-05-31 17:59:28 +0100 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-06-03 19:10:09 +0900 |
commit | 2ef7a2953c81ee6b341e3ffb33570adc894cf4a5 (patch) | |
tree | 98723c186755eed6b067867f0dd80eba352c544e /arch/arm64/kernel/topology.c | |
parent | f70b281b59a871545362a494d99a644153fbbaac (diff) | |
download | linux-stable-2ef7a2953c81ee6b341e3ffb33570adc894cf4a5.tar.gz linux-stable-2ef7a2953c81ee6b341e3ffb33570adc894cf4a5.tar.bz2 linux-stable-2ef7a2953c81ee6b341e3ffb33570adc894cf4a5.zip |
arm, arm64: factorize common cpu capacity default code
arm and arm64 share lot of code relative to parsing CPU capacity
information from DT, using that information for appropriate scaling and
exposing a sysfs interface for chaging such values at runtime.
Factorize such code in a common place (driver/base/arch_topology.c) in
preparation for further additions.
Suggested-by: Will Deacon <will.deacon@arm.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm64/kernel/topology.c')
-rw-r--r-- | arch/arm64/kernel/topology.c | 219 |
1 files changed, 3 insertions, 216 deletions
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 08243533e5ee..c5bc31eb97e8 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -11,7 +11,6 @@ * for more details. */ -#include <linux/acpi.h> #include <linux/cpu.h> #include <linux/cpumask.h> #include <linux/init.h> @@ -23,226 +22,14 @@ #include <linux/sched/topology.h> #include <linux/slab.h> #include <linux/string.h> -#include <linux/cpufreq.h> #include <asm/cpu.h> #include <asm/cputype.h> #include <asm/topology.h> -static DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE; -static DEFINE_MUTEX(cpu_scale_mutex); - -unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) -{ - return per_cpu(cpu_scale, cpu); -} - -static void set_capacity_scale(unsigned int cpu, unsigned long capacity) -{ - per_cpu(cpu_scale, cpu) = capacity; -} - -static ssize_t cpu_capacity_show(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - struct cpu *cpu = container_of(dev, struct cpu, dev); - - return sprintf(buf, "%lu\n", - arch_scale_cpu_capacity(NULL, cpu->dev.id)); -} - -static ssize_t cpu_capacity_store(struct device *dev, - struct device_attribute *attr, - const char *buf, - size_t count) -{ - struct cpu *cpu = container_of(dev, struct cpu, dev); - int this_cpu = cpu->dev.id, i; - unsigned long new_capacity; - ssize_t ret; - - if (count) { - ret = kstrtoul(buf, 0, &new_capacity); - if (ret) - return ret; - if (new_capacity > SCHED_CAPACITY_SCALE) - return -EINVAL; - - mutex_lock(&cpu_scale_mutex); - for_each_cpu(i, &cpu_topology[this_cpu].core_sibling) - set_capacity_scale(i, new_capacity); - mutex_unlock(&cpu_scale_mutex); - } - - return count; -} - -static DEVICE_ATTR_RW(cpu_capacity); - -static int register_cpu_capacity_sysctl(void) -{ - int i; - struct device *cpu; - - for_each_possible_cpu(i) { - cpu = get_cpu_device(i); - if (!cpu) { - pr_err("%s: too early to get CPU%d device!\n", - __func__, i); - continue; - } - device_create_file(cpu, &dev_attr_cpu_capacity); - } - - return 0; -} -subsys_initcall(register_cpu_capacity_sysctl); - -static u32 capacity_scale; -static u32 *raw_capacity; -static bool cap_parsing_failed; - -static void __init parse_cpu_capacity(struct device_node *cpu_node, int cpu) -{ - int ret; - u32 cpu_capacity; - - if (cap_parsing_failed) - return; - - ret = of_property_read_u32(cpu_node, - "capacity-dmips-mhz", - &cpu_capacity); - if (!ret) { - if (!raw_capacity) { - raw_capacity = kcalloc(num_possible_cpus(), - sizeof(*raw_capacity), - GFP_KERNEL); - if (!raw_capacity) { - pr_err("cpu_capacity: failed to allocate memory for raw capacities\n"); - cap_parsing_failed = true; - return; - } - } - capacity_scale = max(cpu_capacity, capacity_scale); - raw_capacity[cpu] = cpu_capacity; - pr_debug("cpu_capacity: %s cpu_capacity=%u (raw)\n", - cpu_node->full_name, raw_capacity[cpu]); - } else { - if (raw_capacity) { - pr_err("cpu_capacity: missing %s raw capacity\n", - cpu_node->full_name); - pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n"); - } - cap_parsing_failed = true; - kfree(raw_capacity); - } -} - -static void normalize_cpu_capacity(void) -{ - u64 capacity; - int cpu; - - if (!raw_capacity || cap_parsing_failed) - return; - - pr_debug("cpu_capacity: capacity_scale=%u\n", capacity_scale); - mutex_lock(&cpu_scale_mutex); - for_each_possible_cpu(cpu) { - pr_debug("cpu_capacity: cpu=%d raw_capacity=%u\n", - cpu, raw_capacity[cpu]); - capacity = (raw_capacity[cpu] << SCHED_CAPACITY_SHIFT) - / capacity_scale; - set_capacity_scale(cpu, capacity); - pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n", - cpu, arch_scale_cpu_capacity(NULL, cpu)); - } - mutex_unlock(&cpu_scale_mutex); -} - -#ifdef CONFIG_CPU_FREQ -static cpumask_var_t cpus_to_visit; -static bool cap_parsing_done; -static void parsing_done_workfn(struct work_struct *work); -static DECLARE_WORK(parsing_done_work, parsing_done_workfn); - -static int -init_cpu_capacity_callback(struct notifier_block *nb, - unsigned long val, - void *data) -{ - struct cpufreq_policy *policy = data; - int cpu; - - if (cap_parsing_failed || cap_parsing_done) - return 0; - - switch (val) { - case CPUFREQ_NOTIFY: - pr_debug("cpu_capacity: init cpu capacity for CPUs [%*pbl] (to_visit=%*pbl)\n", - cpumask_pr_args(policy->related_cpus), - cpumask_pr_args(cpus_to_visit)); - cpumask_andnot(cpus_to_visit, - cpus_to_visit, - policy->related_cpus); - for_each_cpu(cpu, policy->related_cpus) { - raw_capacity[cpu] = arch_scale_cpu_capacity(NULL, cpu) * - policy->cpuinfo.max_freq / 1000UL; - capacity_scale = max(raw_capacity[cpu], capacity_scale); - } - if (cpumask_empty(cpus_to_visit)) { - normalize_cpu_capacity(); - kfree(raw_capacity); - pr_debug("cpu_capacity: parsing done\n"); - cap_parsing_done = true; - schedule_work(&parsing_done_work); - } - } - return 0; -} - -static struct notifier_block init_cpu_capacity_notifier = { - .notifier_call = init_cpu_capacity_callback, -}; - -static int __init register_cpufreq_notifier(void) -{ - /* - * on ACPI-based systems we need to use the default cpu capacity - * until we have the necessary code to parse the cpu capacity, so - * skip registering cpufreq notifier. - */ - if (!acpi_disabled || cap_parsing_failed) - return -EINVAL; - - if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL)) { - pr_err("cpu_capacity: failed to allocate memory for cpus_to_visit\n"); - return -ENOMEM; - } - cpumask_copy(cpus_to_visit, cpu_possible_mask); - - return cpufreq_register_notifier(&init_cpu_capacity_notifier, - CPUFREQ_POLICY_NOTIFIER); -} -core_initcall(register_cpufreq_notifier); - -static void parsing_done_workfn(struct work_struct *work) -{ - cpufreq_unregister_notifier(&init_cpu_capacity_notifier, - CPUFREQ_POLICY_NOTIFIER); -} - -#else -static int __init free_raw_capacity(void) -{ - kfree(raw_capacity); - - return 0; -} -core_initcall(free_raw_capacity); -#endif +extern bool cap_parsing_failed; +extern void normalize_cpu_capacity(void); +extern int __init parse_cpu_capacity(struct device_node *cpu_node, int cpu); static int __init get_cpu_for_node(struct device_node *node) { |