diff options
Diffstat (limited to 'arch/i386/oprofile/nmi_int.c')
-rw-r--r-- | arch/i386/oprofile/nmi_int.c | 427 |
1 files changed, 427 insertions, 0 deletions
diff --git a/arch/i386/oprofile/nmi_int.c b/arch/i386/oprofile/nmi_int.c new file mode 100644 index 00000000000..3492d961d3f --- /dev/null +++ b/arch/i386/oprofile/nmi_int.c @@ -0,0 +1,427 @@ +/** + * @file nmi_int.c + * + * @remark Copyright 2002 OProfile authors + * @remark Read the file COPYING + * + * @author John Levon <levon@movementarian.org> + */ + +#include <linux/init.h> +#include <linux/notifier.h> +#include <linux/smp.h> +#include <linux/oprofile.h> +#include <linux/sysdev.h> +#include <linux/slab.h> +#include <asm/nmi.h> +#include <asm/msr.h> +#include <asm/apic.h> + +#include "op_counter.h" +#include "op_x86_model.h" + +static struct op_x86_model_spec const * model; +static struct op_msrs cpu_msrs[NR_CPUS]; +static unsigned long saved_lvtpc[NR_CPUS]; + +static int nmi_start(void); +static void nmi_stop(void); + +/* 0 == registered but off, 1 == registered and on */ +static int nmi_enabled = 0; + +#ifdef CONFIG_PM + +static int nmi_suspend(struct sys_device *dev, u32 state) +{ + if (nmi_enabled == 1) + nmi_stop(); + return 0; +} + + +static int nmi_resume(struct sys_device *dev) +{ + if (nmi_enabled == 1) + nmi_start(); + return 0; +} + + +static struct sysdev_class oprofile_sysclass = { + set_kset_name("oprofile"), + .resume = nmi_resume, + .suspend = nmi_suspend, +}; + + +static struct sys_device device_oprofile = { + .id = 0, + .cls = &oprofile_sysclass, +}; + + +static int __init init_driverfs(void) +{ + int error; + if (!(error = sysdev_class_register(&oprofile_sysclass))) + error = sysdev_register(&device_oprofile); + return error; +} + + +static void exit_driverfs(void) +{ + sysdev_unregister(&device_oprofile); + sysdev_class_unregister(&oprofile_sysclass); +} + +#else +#define init_driverfs() do { } while (0) +#define exit_driverfs() do { } while (0) +#endif /* CONFIG_PM */ + + +static int nmi_callback(struct pt_regs * regs, int cpu) +{ + return model->check_ctrs(regs, &cpu_msrs[cpu]); +} + + +static void nmi_cpu_save_registers(struct op_msrs * msrs) +{ + unsigned int const nr_ctrs = model->num_counters; + unsigned int const nr_ctrls = model->num_controls; + struct op_msr * counters = msrs->counters; + struct op_msr * controls = msrs->controls; + unsigned int i; + + for (i = 0; i < nr_ctrs; ++i) { + rdmsr(counters[i].addr, + counters[i].saved.low, + counters[i].saved.high); + } + + for (i = 0; i < nr_ctrls; ++i) { + rdmsr(controls[i].addr, + controls[i].saved.low, + controls[i].saved.high); + } +} + + +static void nmi_save_registers(void * dummy) +{ + int cpu = smp_processor_id(); + struct op_msrs * msrs = &cpu_msrs[cpu]; + model->fill_in_addresses(msrs); + nmi_cpu_save_registers(msrs); +} + + +static void free_msrs(void) +{ + int i; + for (i = 0; i < NR_CPUS; ++i) { + kfree(cpu_msrs[i].counters); + cpu_msrs[i].counters = NULL; + kfree(cpu_msrs[i].controls); + cpu_msrs[i].controls = NULL; + } +} + + +static int allocate_msrs(void) +{ + int success = 1; + size_t controls_size = sizeof(struct op_msr) * model->num_controls; + size_t counters_size = sizeof(struct op_msr) * model->num_counters; + + int i; + for (i = 0; i < NR_CPUS; ++i) { + if (!cpu_online(i)) + continue; + + cpu_msrs[i].counters = kmalloc(counters_size, GFP_KERNEL); + if (!cpu_msrs[i].counters) { + success = 0; + break; + } + cpu_msrs[i].controls = kmalloc(controls_size, GFP_KERNEL); + if (!cpu_msrs[i].controls) { + success = 0; + break; + } + } + + if (!success) + free_msrs(); + + return success; +} + + +static void nmi_cpu_setup(void * dummy) +{ + int cpu = smp_processor_id(); + struct op_msrs * msrs = &cpu_msrs[cpu]; + spin_lock(&oprofilefs_lock); + model->setup_ctrs(msrs); + spin_unlock(&oprofilefs_lock); + saved_lvtpc[cpu] = apic_read(APIC_LVTPC); + apic_write(APIC_LVTPC, APIC_DM_NMI); +} + + +static int nmi_setup(void) +{ + if (!allocate_msrs()) + return -ENOMEM; + + /* We walk a thin line between law and rape here. + * We need to be careful to install our NMI handler + * without actually triggering any NMIs as this will + * break the core code horrifically. + */ + if (reserve_lapic_nmi() < 0) { + free_msrs(); + return -EBUSY; + } + /* We need to serialize save and setup for HT because the subset + * of msrs are distinct for save and setup operations + */ + on_each_cpu(nmi_save_registers, NULL, 0, 1); + on_each_cpu(nmi_cpu_setup, NULL, 0, 1); + set_nmi_callback(nmi_callback); + nmi_enabled = 1; + return 0; +} + + +static void nmi_restore_registers(struct op_msrs * msrs) +{ + unsigned int const nr_ctrs = model->num_counters; + unsigned int const nr_ctrls = model->num_controls; + struct op_msr * counters = msrs->counters; + struct op_msr * controls = msrs->controls; + unsigned int i; + + for (i = 0; i < nr_ctrls; ++i) { + wrmsr(controls[i].addr, + controls[i].saved.low, + controls[i].saved.high); + } + + for (i = 0; i < nr_ctrs; ++i) { + wrmsr(counters[i].addr, + counters[i].saved.low, + counters[i].saved.high); + } +} + + +static void nmi_cpu_shutdown(void * dummy) +{ + unsigned int v; + int cpu = smp_processor_id(); + struct op_msrs * msrs = &cpu_msrs[cpu]; + + /* restoring APIC_LVTPC can trigger an apic error because the delivery + * mode and vector nr combination can be illegal. That's by design: on + * power on apic lvt contain a zero vector nr which are legal only for + * NMI delivery mode. So inhibit apic err before restoring lvtpc + */ + v = apic_read(APIC_LVTERR); + apic_write(APIC_LVTERR, v | APIC_LVT_MASKED); + apic_write(APIC_LVTPC, saved_lvtpc[cpu]); + apic_write(APIC_LVTERR, v); + nmi_restore_registers(msrs); +} + + +static void nmi_shutdown(void) +{ + nmi_enabled = 0; + on_each_cpu(nmi_cpu_shutdown, NULL, 0, 1); + unset_nmi_callback(); + release_lapic_nmi(); + free_msrs(); +} + + +static void nmi_cpu_start(void * dummy) +{ + struct op_msrs const * msrs = &cpu_msrs[smp_processor_id()]; + model->start(msrs); +} + + +static int nmi_start(void) +{ + on_each_cpu(nmi_cpu_start, NULL, 0, 1); + return 0; +} + + +static void nmi_cpu_stop(void * dummy) +{ + struct op_msrs const * msrs = &cpu_msrs[smp_processor_id()]; + model->stop(msrs); +} + + +static void nmi_stop(void) +{ + on_each_cpu(nmi_cpu_stop, NULL, 0, 1); +} + + +struct op_counter_config counter_config[OP_MAX_COUNTER]; + +static int nmi_create_files(struct super_block * sb, struct dentry * root) +{ + unsigned int i; + + for (i = 0; i < model->num_counters; ++i) { + struct dentry * dir; + char buf[2]; + + snprintf(buf, 2, "%d", i); + dir = oprofilefs_mkdir(sb, root, buf); + oprofilefs_create_ulong(sb, dir, "enabled", &counter_config[i].enabled); + oprofilefs_create_ulong(sb, dir, "event", &counter_config[i].event); + oprofilefs_create_ulong(sb, dir, "count", &counter_config[i].count); + oprofilefs_create_ulong(sb, dir, "unit_mask", &counter_config[i].unit_mask); + oprofilefs_create_ulong(sb, dir, "kernel", &counter_config[i].kernel); + oprofilefs_create_ulong(sb, dir, "user", &counter_config[i].user); + } + + return 0; +} + + +static int __init p4_init(char ** cpu_type) +{ + __u8 cpu_model = boot_cpu_data.x86_model; + + if (cpu_model > 4) + return 0; + +#ifndef CONFIG_SMP + *cpu_type = "i386/p4"; + model = &op_p4_spec; + return 1; +#else + switch (smp_num_siblings) { + case 1: + *cpu_type = "i386/p4"; + model = &op_p4_spec; + return 1; + + case 2: + *cpu_type = "i386/p4-ht"; + model = &op_p4_ht2_spec; + return 1; + } +#endif + + printk(KERN_INFO "oprofile: P4 HyperThreading detected with > 2 threads\n"); + printk(KERN_INFO "oprofile: Reverting to timer mode.\n"); + return 0; +} + + +static int __init ppro_init(char ** cpu_type) +{ + __u8 cpu_model = boot_cpu_data.x86_model; + + if (cpu_model > 0xd) + return 0; + + if (cpu_model == 9) { + *cpu_type = "i386/p6_mobile"; + } else if (cpu_model > 5) { + *cpu_type = "i386/piii"; + } else if (cpu_model > 2) { + *cpu_type = "i386/pii"; + } else { + *cpu_type = "i386/ppro"; + } + + model = &op_ppro_spec; + return 1; +} + +/* in order to get driverfs right */ +static int using_nmi; + +int __init nmi_init(struct oprofile_operations *ops) +{ + __u8 vendor = boot_cpu_data.x86_vendor; + __u8 family = boot_cpu_data.x86; + char *cpu_type; + + if (!cpu_has_apic) + return -ENODEV; + + switch (vendor) { + case X86_VENDOR_AMD: + /* Needs to be at least an Athlon (or hammer in 32bit mode) */ + + switch (family) { + default: + return -ENODEV; + case 6: + model = &op_athlon_spec; + cpu_type = "i386/athlon"; + break; + case 0xf: + model = &op_athlon_spec; + /* Actually it could be i386/hammer too, but give + user space an consistent name. */ + cpu_type = "x86-64/hammer"; + break; + } + break; + + case X86_VENDOR_INTEL: + switch (family) { + /* Pentium IV */ + case 0xf: + if (!p4_init(&cpu_type)) + return -ENODEV; + break; + + /* A P6-class processor */ + case 6: + if (!ppro_init(&cpu_type)) + return -ENODEV; + break; + + default: + return -ENODEV; + } + break; + + default: + return -ENODEV; + } + + init_driverfs(); + using_nmi = 1; + ops->create_files = nmi_create_files; + ops->setup = nmi_setup; + ops->shutdown = nmi_shutdown; + ops->start = nmi_start; + ops->stop = nmi_stop; + ops->cpu_type = cpu_type; + printk(KERN_INFO "oprofile: using NMI interrupt.\n"); + return 0; +} + + +void nmi_exit(void) +{ + if (using_nmi) + exit_driverfs(); +} |