diff options
author | Mark Brown <broonie@linaro.org> | 2013-12-11 22:36:52 +0000 |
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committer | Mark Brown <broonie@linaro.org> | 2013-12-11 22:36:52 +0000 |
commit | 48a904c88d3768312b638ae2cffce6fa51231acc (patch) | |
tree | 3fc0a4e90a15bb9bf61d97a6431daaa6b0513596 /arch | |
parent | 09905258e4846b60a6b1e2432c0f1653a2f49641 (diff) | |
parent | e101473817ddc5e10919e4e22c3b421a350ad742 (diff) |
Merge remote-tracking branch 'lsk/v3.10/topic/arm64-topology' into linux-linaro-lsk
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arm64/Kconfig | 8 | ||||
-rw-r--r-- | arch/arm64/include/asm/topology.h | 42 | ||||
-rw-r--r-- | arch/arm64/kernel/Makefile | 1 | ||||
-rw-r--r-- | arch/arm64/kernel/smp.c | 12 | ||||
-rw-r--r-- | arch/arm64/kernel/topology.c | 418 | ||||
-rw-r--r-- | arch/powerpc/include/asm/prom.h | 3 | ||||
-rw-r--r-- | arch/powerpc/kernel/prom.c | 43 |
7 files changed, 483 insertions, 44 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index c2b4a765ff4..37cbbdd7248 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -144,6 +144,14 @@ config SMP If you don't know what to do here, say N. +config ARM_CPU_TOPOLOGY + bool "Support CPU topology definition" + depends on SMP + default y + help + Support CPU topology definition, based on configuration + provided by the firmware. + config NR_CPUS int "Maximum number of CPUs (2-32)" range 2 32 diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h new file mode 100644 index 00000000000..611edefaeaf --- /dev/null +++ b/arch/arm64/include/asm/topology.h @@ -0,0 +1,42 @@ +#ifndef _ASM_ARM_TOPOLOGY_H +#define _ASM_ARM_TOPOLOGY_H + +#ifdef CONFIG_ARM_CPU_TOPOLOGY + +#include <linux/cpumask.h> + +struct cputopo_arm { + int thread_id; + int core_id; + int socket_id; + cpumask_t thread_sibling; + cpumask_t core_sibling; +}; + +extern struct cputopo_arm cpu_topology[NR_CPUS]; + +#define topology_physical_package_id(cpu) (cpu_topology[cpu].socket_id) +#define topology_core_id(cpu) (cpu_topology[cpu].core_id) +#define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling) +#define topology_thread_cpumask(cpu) (&cpu_topology[cpu].thread_sibling) + +#define mc_capable() (cpu_topology[0].socket_id != -1) +#define smt_capable() (cpu_topology[0].thread_id != -1) + +void init_cpu_topology(void); +void store_cpu_topology(unsigned int cpuid); +const struct cpumask *cpu_coregroup_mask(int cpu); +int cluster_to_logical_mask(unsigned int socket_id, cpumask_t *cluster_mask); + +#else + +static inline void init_cpu_topology(void) { } +static inline void store_cpu_topology(unsigned int cpuid) { } +static inline int cluster_to_logical_mask(unsigned int socket_id, + cpumask_t *cluster_mask) { return -EINVAL; } + +#endif + +#include <asm-generic/topology.h> + +#endif /* _ASM_ARM_TOPOLOGY_H */ diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 7b4b564961d..4e4c80d1150 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -18,6 +18,7 @@ arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o smp_psci.o arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o +arm64-obj-$(CONFIG_ARM_CPU_TOPOLOGY) += topology.o obj-y += $(arm64-obj-y) vdso/ obj-m += $(arm64-obj-m) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index a28d2859932..8d8a1f2af29 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -161,6 +161,11 @@ int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) return ret; } +static void __cpuinit smp_store_cpu_info(unsigned int cpuid) +{ + store_cpu_topology(cpuid); +} + /* * This is the secondary CPU boot entry. We're using this CPUs * idle thread stack, but a set of temporary page tables. @@ -209,6 +214,8 @@ asmlinkage void __cpuinit secondary_start_kernel(void) local_irq_enable(); local_fiq_enable(); + smp_store_cpu_info(cpu); + /* * OK, now it's safe to let the boot CPU continue. Wait for * the CPU migration code to notice that the CPU is online @@ -389,6 +396,11 @@ void __init smp_prepare_cpus(unsigned int max_cpus) int cpu, err; unsigned int ncores = num_possible_cpus(); + init_cpu_topology(); + + smp_store_cpu_info(smp_processor_id()); + + /* * are we trying to boot more cores than exist? */ diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c new file mode 100644 index 00000000000..83d6919d4e0 --- /dev/null +++ b/arch/arm64/kernel/topology.c @@ -0,0 +1,418 @@ +/* + * arch/arm64/kernel/topology.c + * + * Copyright (C) 2011,2013 Linaro Limited. + * Written by: Vincent Guittot + * + * based on arch/sh/kernel/topology.c + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/cpu.h> +#include <linux/cpumask.h> +#include <linux/export.h> +#include <linux/init.h> +#include <linux/percpu.h> +#include <linux/node.h> +#include <linux/nodemask.h> +#include <linux/of.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#include <asm/cputype.h> +#include <asm/smp_plat.h> +#include <asm/topology.h> + +/* + * cpu power scale management + */ + +/* + * cpu power table + * This per cpu data structure describes the relative capacity of each core. + * On a heteregenous system, cores don't have the same computation capacity + * and we reflect that difference in the cpu_power field so the scheduler can + * take this difference into account during load balance. A per cpu structure + * is preferred because each CPU updates its own cpu_power field during the + * load balance except for idle cores. One idle core is selected to run the + * rebalance_domains for all idle cores and the cpu_power can be updated + * during this sequence. + */ +static DEFINE_PER_CPU(unsigned long, cpu_scale); + +unsigned long arch_scale_freq_power(struct sched_domain *sd, int cpu) +{ + return per_cpu(cpu_scale, cpu); +} + +static void set_power_scale(unsigned int cpu, unsigned long power) +{ + per_cpu(cpu_scale, cpu) = power; +} + +#ifdef CONFIG_OF +struct cpu_efficiency { + const char *compatible; + unsigned long efficiency; +}; + +/* + * Table of relative efficiency of each processors + * The efficiency value must fit in 20bit and the final + * cpu_scale value must be in the range + * 0 < cpu_scale < 3*SCHED_POWER_SCALE/2 + * in order to return at most 1 when DIV_ROUND_CLOSEST + * is used to compute the capacity of a CPU. + * Processors that are not defined in the table, + * use the default SCHED_POWER_SCALE value for cpu_scale. + */ +static const struct cpu_efficiency table_efficiency[] = { + { "arm,cortex-a57", 3891 }, + { "arm,cortex-a53", 2048 }, + { NULL, }, +}; + +static unsigned long *__cpu_capacity; +#define cpu_capacity(cpu) __cpu_capacity[cpu] + +static unsigned long middle_capacity = 1; +static int cluster_id; + +static int __init get_cpu_for_node(struct device_node *node) +{ + struct device_node *cpu_node; + int cpu; + + cpu_node = of_parse_phandle(node, "cpu", 0); + if (!cpu_node) { + pr_crit("%s: Unable to parse CPU phandle\n", node->full_name); + return -1; + } + + for_each_possible_cpu(cpu) { + if (of_get_cpu_node(cpu, NULL) == cpu_node) + return cpu; + } + + pr_crit("Unable to find CPU node for %s\n", cpu_node->full_name); + return -1; +} + +static void __init parse_core(struct device_node *core, int core_id) +{ + char name[10]; + bool leaf = true; + int i, cpu; + struct device_node *t; + + i = 0; + do { + snprintf(name, sizeof(name), "thread%d", i); + t = of_get_child_by_name(core, name); + if (t) { + leaf = false; + cpu = get_cpu_for_node(t); + if (cpu) { + pr_info("CPU%d: socket %d core %d thread %d\n", + cpu, cluster_id, core_id, i); + cpu_topology[cpu].socket_id = cluster_id; + cpu_topology[cpu].core_id = core_id; + cpu_topology[cpu].thread_id = i; + } else { + pr_err("%s: Can't get CPU for thread\n", + t->full_name); + } + } + i++; + } while (t); + + cpu = get_cpu_for_node(core); + if (cpu >= 0) { + if (!leaf) { + pr_err("%s: Core has both threads and CPU\n", + core->full_name); + return; + } + + pr_info("CPU%d: socket %d core %d\n", + cpu, cluster_id, core_id); + cpu_topology[cpu].socket_id = cluster_id; + cpu_topology[cpu].core_id = core_id; + } else if (leaf) { + pr_err("%s: Can't get CPU for leaf core\n", core->full_name); + } +} + +static void __init parse_cluster(struct device_node *cluster) +{ + char name[10]; + bool leaf = true; + bool has_cores = false; + struct device_node *c; + int core_id = 0; + int i; + + /* + * First check for child clusters; we currently ignore any + * information about the nesting of clusters and present the + * scheduler with a flat list of them. + */ + i = 0; + do { + snprintf(name, sizeof(name), "cluster%d", i); + c = of_get_child_by_name(cluster, name); + if (c) { + parse_cluster(c); + leaf = false; + } + i++; + } while (c); + + /* Now check for cores */ + i = 0; + do { + snprintf(name, sizeof(name), "core%d", i); + c = of_get_child_by_name(cluster, name); + if (c) { + has_cores = true; + + if (leaf) + parse_core(c, core_id++); + else + pr_err("%s: Non-leaf cluster with core %s\n", + cluster->full_name, name); + } + i++; + } while (c); + + if (leaf && !has_cores) + pr_warn("%s: empty cluster\n", cluster->full_name); + + if (leaf) + cluster_id++; +} + +/* + * Iterate all CPUs' descriptor in DT and compute the efficiency + * (as per table_efficiency). Also calculate a middle efficiency + * as close as possible to (max{eff_i} - min{eff_i}) / 2 + * This is later used to scale the cpu_power field such that an + * 'average' CPU is of middle power. Also see the comments near + * table_efficiency[] and update_cpu_power(). + */ +static void __init parse_dt_topology(void) +{ + const struct cpu_efficiency *cpu_eff; + struct device_node *cn = NULL; + unsigned long min_capacity = (unsigned long)(-1); + unsigned long max_capacity = 0; + unsigned long capacity = 0; + int alloc_size, cpu; + + alloc_size = nr_cpu_ids * sizeof(*__cpu_capacity); + __cpu_capacity = kzalloc(alloc_size, GFP_NOWAIT); + + cn = of_find_node_by_path("/cpus"); + if (!cn) { + pr_err("No CPU information found in DT\n"); + return; + } + + /* + * If topology is provided as a cpu-map it is essentially a + * root cluster. + */ + cn = of_find_node_by_name(cn, "cpu-map"); + if (!cn) + return; + parse_cluster(cn); + + for_each_possible_cpu(cpu) { + const u32 *rate; + int len; + + /* Too early to use cpu->of_node */ + cn = of_get_cpu_node(cpu, NULL); + if (!cn) { + pr_err("Missing device node for CPU %d\n", cpu); + continue; + } + + /* check if the cpu is marked as "disabled", if so ignore */ + if (!of_device_is_available(cn)) + continue; + + for (cpu_eff = table_efficiency; cpu_eff->compatible; cpu_eff++) + if (of_device_is_compatible(cn, cpu_eff->compatible)) + break; + + if (cpu_eff->compatible == NULL) { + pr_warn("%s: Unknown CPU type\n", cn->full_name); + continue; + } + + rate = of_get_property(cn, "clock-frequency", &len); + if (!rate || len != 4) { + pr_err("%s: Missing clock-frequency property\n", + cn->full_name); + continue; + } + + capacity = ((be32_to_cpup(rate)) >> 20) * cpu_eff->efficiency; + + /* Save min capacity of the system */ + if (capacity < min_capacity) + min_capacity = capacity; + + /* Save max capacity of the system */ + if (capacity > max_capacity) + max_capacity = capacity; + + cpu_capacity(cpu) = capacity; + } + + /* If min and max capacities are equal we bypass the update of the + * cpu_scale because all CPUs have the same capacity. Otherwise, we + * compute a middle_capacity factor that will ensure that the capacity + * of an 'average' CPU of the system will be as close as possible to + * SCHED_POWER_SCALE, which is the default value, but with the + * constraint explained near table_efficiency[]. + */ + if (min_capacity == max_capacity) + return; + else if (4 * max_capacity < (3 * (max_capacity + min_capacity))) + middle_capacity = (min_capacity + max_capacity) + >> (SCHED_POWER_SHIFT+1); + else + middle_capacity = ((max_capacity / 3) + >> (SCHED_POWER_SHIFT-1)) + 1; + +} + +/* + * Look for a customed capacity of a CPU in the cpu_topo_data table during the + * boot. The update of all CPUs is in O(n^2) for heteregeneous system but the + * function returns directly for SMP system. + */ +static void update_cpu_power(unsigned int cpu) +{ + if (!cpu_capacity(cpu)) + return; + + set_power_scale(cpu, cpu_capacity(cpu) / middle_capacity); + + pr_info("CPU%u: update cpu_power %lu\n", + cpu, arch_scale_freq_power(NULL, cpu)); +} + +#else +static inline void parse_dt_topology(void) {} +static inline void update_cpu_power(unsigned int cpuid) {} +#endif + +/* + * cpu topology table + */ +struct cputopo_arm cpu_topology[NR_CPUS]; +EXPORT_SYMBOL_GPL(cpu_topology); + +const struct cpumask *cpu_coregroup_mask(int cpu) +{ + return &cpu_topology[cpu].core_sibling; +} + +static void update_siblings_masks(unsigned int cpuid) +{ + struct cputopo_arm *cpu_topo, *cpuid_topo = &cpu_topology[cpuid]; + int cpu; + + /* update core and thread sibling masks */ + for_each_possible_cpu(cpu) { + cpu_topo = &cpu_topology[cpu]; + + if (cpuid_topo->socket_id != cpu_topo->socket_id) + continue; + + cpumask_set_cpu(cpuid, &cpu_topo->core_sibling); + if (cpu != cpuid) + cpumask_set_cpu(cpu, &cpuid_topo->core_sibling); + + if (cpuid_topo->core_id != cpu_topo->core_id) + continue; + + cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling); + if (cpu != cpuid) + cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling); + } + smp_wmb(); +} + +void store_cpu_topology(unsigned int cpuid) +{ + struct cputopo_arm *cpuid_topo = &cpu_topology[cpuid]; + + /* DT should have been parsed by the time we get here */ + if (cpuid_topo->core_id == -1) + pr_info("CPU%u: No topology information configured\n", cpuid); + else + update_siblings_masks(cpuid); + + update_cpu_power(cpuid); +} + + +/* + * cluster_to_logical_mask - return cpu logical mask of CPUs in a cluster + * @socket_id: cluster HW identifier + * @cluster_mask: the cpumask location to be initialized, modified by the + * function only if return value == 0 + * + * Return: + * + * 0 on success + * -EINVAL if cluster_mask is NULL or there is no record matching socket_id + */ +int cluster_to_logical_mask(unsigned int socket_id, cpumask_t *cluster_mask) +{ + int cpu; + + if (!cluster_mask) + return -EINVAL; + + for_each_online_cpu(cpu) { + if (socket_id == topology_physical_package_id(cpu)) { + cpumask_copy(cluster_mask, topology_core_cpumask(cpu)); + return 0; + } + } + + return -EINVAL; +} + +/* + * init_cpu_topology is called at boot when only one cpu is running + * which prevent simultaneous write access to cpu_topology array + */ +void __init init_cpu_topology(void) +{ + unsigned int cpu; + + /* init core mask and power*/ + for_each_possible_cpu(cpu) { + struct cputopo_arm *cpu_topo = &(cpu_topology[cpu]); + + cpu_topo->thread_id = -1; + cpu_topo->core_id = -1; + cpu_topo->socket_id = -1; + cpumask_clear(&cpu_topo->core_sibling); + cpumask_clear(&cpu_topo->thread_sibling); + + set_power_scale(cpu, SCHED_POWER_SCALE); + } + smp_wmb(); + + parse_dt_topology(); +} diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h index bc2da154f68..ac204e02292 100644 --- a/arch/powerpc/include/asm/prom.h +++ b/arch/powerpc/include/asm/prom.h @@ -43,9 +43,6 @@ void of_parse_dma_window(struct device_node *dn, const void *dma_window_prop, extern void kdump_move_device_tree(void); -/* CPU OF node matching */ -struct device_node *of_get_cpu_node(int cpu, unsigned int *thread); - /* cache lookup */ struct device_node *of_find_next_cache_node(struct device_node *np); diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index 8b6f7a99cce..00610a34fb9 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -827,49 +827,10 @@ static int __init prom_reconfig_setup(void) __initcall(prom_reconfig_setup); #endif -/* Find the device node for a given logical cpu number, also returns the cpu - * local thread number (index in ibm,interrupt-server#s) if relevant and - * asked for (non NULL) - */ -struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) +bool arch_match_cpu_phys_id(int cpu, u64 phys_id) { - int hardid; - struct device_node *np; - - hardid = get_hard_smp_processor_id(cpu); - - for_each_node_by_type(np, "cpu") { - const u32 *intserv; - unsigned int plen, t; - - /* Check for ibm,ppc-interrupt-server#s. If it doesn't exist - * fallback to "reg" property and assume no threads - */ - intserv = of_get_property(np, "ibm,ppc-interrupt-server#s", - &plen); - if (intserv == NULL) { - const u32 *reg = of_get_property(np, "reg", NULL); - if (reg == NULL) - continue; - if (*reg == hardid) { - if (thread) - *thread = 0; - return np; - } - } else { - plen /= sizeof(u32); - for (t = 0; t < plen; t++) { - if (hardid == intserv[t]) { - if (thread) - *thread = t; - return np; - } - } - } - } - return NULL; + return (int)phys_id == get_hard_smp_processor_id(cpu); } -EXPORT_SYMBOL(of_get_cpu_node); #if defined(CONFIG_DEBUG_FS) && defined(DEBUG) static struct debugfs_blob_wrapper flat_dt_blob; |