diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/x86/oprofile/nmi_int.c | |
parent | Initial commit. (diff) | |
download | linux-upstream/4.19.249.tar.xz linux-upstream/4.19.249.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/oprofile/nmi_int.c')
-rw-r--r-- | arch/x86/oprofile/nmi_int.c | 780 |
1 files changed, 780 insertions, 0 deletions
diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c new file mode 100644 index 000000000..a7a767726 --- /dev/null +++ b/arch/x86/oprofile/nmi_int.c @@ -0,0 +1,780 @@ +/** + * @file nmi_int.c + * + * @remark Copyright 2002-2009 OProfile authors + * @remark Read the file COPYING + * + * @author John Levon <levon@movementarian.org> + * @author Robert Richter <robert.richter@amd.com> + * @author Barry Kasindorf <barry.kasindorf@amd.com> + * @author Jason Yeh <jason.yeh@amd.com> + * @author Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> + */ + +#include <linux/init.h> +#include <linux/notifier.h> +#include <linux/smp.h> +#include <linux/oprofile.h> +#include <linux/syscore_ops.h> +#include <linux/slab.h> +#include <linux/moduleparam.h> +#include <linux/kdebug.h> +#include <linux/cpu.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 *model; +static DEFINE_PER_CPU(struct op_msrs, cpu_msrs); +static DEFINE_PER_CPU(unsigned long, saved_lvtpc); + +/* must be protected with get_online_cpus()/put_online_cpus(): */ +static int nmi_enabled; +static int ctr_running; + +struct op_counter_config counter_config[OP_MAX_COUNTER]; + +/* common functions */ + +u64 op_x86_get_ctrl(struct op_x86_model_spec const *model, + struct op_counter_config *counter_config) +{ + u64 val = 0; + u16 event = (u16)counter_config->event; + + val |= ARCH_PERFMON_EVENTSEL_INT; + val |= counter_config->user ? ARCH_PERFMON_EVENTSEL_USR : 0; + val |= counter_config->kernel ? ARCH_PERFMON_EVENTSEL_OS : 0; + val |= (counter_config->unit_mask & 0xFF) << 8; + counter_config->extra &= (ARCH_PERFMON_EVENTSEL_INV | + ARCH_PERFMON_EVENTSEL_EDGE | + ARCH_PERFMON_EVENTSEL_CMASK); + val |= counter_config->extra; + event &= model->event_mask ? model->event_mask : 0xFF; + val |= event & 0xFF; + val |= (u64)(event & 0x0F00) << 24; + + return val; +} + + +static int profile_exceptions_notify(unsigned int val, struct pt_regs *regs) +{ + if (ctr_running) + model->check_ctrs(regs, this_cpu_ptr(&cpu_msrs)); + else if (!nmi_enabled) + return NMI_DONE; + else + model->stop(this_cpu_ptr(&cpu_msrs)); + return NMI_HANDLED; +} + +static void nmi_cpu_save_registers(struct op_msrs *msrs) +{ + struct op_msr *counters = msrs->counters; + struct op_msr *controls = msrs->controls; + unsigned int i; + + for (i = 0; i < model->num_counters; ++i) { + if (counters[i].addr) + rdmsrl(counters[i].addr, counters[i].saved); + } + + for (i = 0; i < model->num_controls; ++i) { + if (controls[i].addr) + rdmsrl(controls[i].addr, controls[i].saved); + } +} + +static void nmi_cpu_start(void *dummy) +{ + struct op_msrs const *msrs = this_cpu_ptr(&cpu_msrs); + if (!msrs->controls) + WARN_ON_ONCE(1); + else + model->start(msrs); +} + +static int nmi_start(void) +{ + get_online_cpus(); + ctr_running = 1; + /* make ctr_running visible to the nmi handler: */ + smp_mb(); + on_each_cpu(nmi_cpu_start, NULL, 1); + put_online_cpus(); + return 0; +} + +static void nmi_cpu_stop(void *dummy) +{ + struct op_msrs const *msrs = this_cpu_ptr(&cpu_msrs); + if (!msrs->controls) + WARN_ON_ONCE(1); + else + model->stop(msrs); +} + +static void nmi_stop(void) +{ + get_online_cpus(); + on_each_cpu(nmi_cpu_stop, NULL, 1); + ctr_running = 0; + put_online_cpus(); +} + +#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX + +static DEFINE_PER_CPU(int, switch_index); + +static inline int has_mux(void) +{ + return !!model->switch_ctrl; +} + +inline int op_x86_phys_to_virt(int phys) +{ + return __this_cpu_read(switch_index) + phys; +} + +inline int op_x86_virt_to_phys(int virt) +{ + return virt % model->num_counters; +} + +static void nmi_shutdown_mux(void) +{ + int i; + + if (!has_mux()) + return; + + for_each_possible_cpu(i) { + kfree(per_cpu(cpu_msrs, i).multiplex); + per_cpu(cpu_msrs, i).multiplex = NULL; + per_cpu(switch_index, i) = 0; + } +} + +static int nmi_setup_mux(void) +{ + size_t multiplex_size = + sizeof(struct op_msr) * model->num_virt_counters; + int i; + + if (!has_mux()) + return 1; + + for_each_possible_cpu(i) { + per_cpu(cpu_msrs, i).multiplex = + kzalloc(multiplex_size, GFP_KERNEL); + if (!per_cpu(cpu_msrs, i).multiplex) + return 0; + } + + return 1; +} + +static void nmi_cpu_setup_mux(int cpu, struct op_msrs const * const msrs) +{ + int i; + struct op_msr *multiplex = msrs->multiplex; + + if (!has_mux()) + return; + + for (i = 0; i < model->num_virt_counters; ++i) { + if (counter_config[i].enabled) { + multiplex[i].saved = -(u64)counter_config[i].count; + } else { + multiplex[i].saved = 0; + } + } + + per_cpu(switch_index, cpu) = 0; +} + +static void nmi_cpu_save_mpx_registers(struct op_msrs *msrs) +{ + struct op_msr *counters = msrs->counters; + struct op_msr *multiplex = msrs->multiplex; + int i; + + for (i = 0; i < model->num_counters; ++i) { + int virt = op_x86_phys_to_virt(i); + if (counters[i].addr) + rdmsrl(counters[i].addr, multiplex[virt].saved); + } +} + +static void nmi_cpu_restore_mpx_registers(struct op_msrs *msrs) +{ + struct op_msr *counters = msrs->counters; + struct op_msr *multiplex = msrs->multiplex; + int i; + + for (i = 0; i < model->num_counters; ++i) { + int virt = op_x86_phys_to_virt(i); + if (counters[i].addr) + wrmsrl(counters[i].addr, multiplex[virt].saved); + } +} + +static void nmi_cpu_switch(void *dummy) +{ + int cpu = smp_processor_id(); + int si = per_cpu(switch_index, cpu); + struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu); + + nmi_cpu_stop(NULL); + nmi_cpu_save_mpx_registers(msrs); + + /* move to next set */ + si += model->num_counters; + if ((si >= model->num_virt_counters) || (counter_config[si].count == 0)) + per_cpu(switch_index, cpu) = 0; + else + per_cpu(switch_index, cpu) = si; + + model->switch_ctrl(model, msrs); + nmi_cpu_restore_mpx_registers(msrs); + + nmi_cpu_start(NULL); +} + + +/* + * Quick check to see if multiplexing is necessary. + * The check should be sufficient since counters are used + * in ordre. + */ +static int nmi_multiplex_on(void) +{ + return counter_config[model->num_counters].count ? 0 : -EINVAL; +} + +static int nmi_switch_event(void) +{ + if (!has_mux()) + return -ENOSYS; /* not implemented */ + if (nmi_multiplex_on() < 0) + return -EINVAL; /* not necessary */ + + get_online_cpus(); + if (ctr_running) + on_each_cpu(nmi_cpu_switch, NULL, 1); + put_online_cpus(); + + return 0; +} + +static inline void mux_init(struct oprofile_operations *ops) +{ + if (has_mux()) + ops->switch_events = nmi_switch_event; +} + +static void mux_clone(int cpu) +{ + if (!has_mux()) + return; + + memcpy(per_cpu(cpu_msrs, cpu).multiplex, + per_cpu(cpu_msrs, 0).multiplex, + sizeof(struct op_msr) * model->num_virt_counters); +} + +#else + +inline int op_x86_phys_to_virt(int phys) { return phys; } +inline int op_x86_virt_to_phys(int virt) { return virt; } +static inline void nmi_shutdown_mux(void) { } +static inline int nmi_setup_mux(void) { return 1; } +static inline void +nmi_cpu_setup_mux(int cpu, struct op_msrs const * const msrs) { } +static inline void mux_init(struct oprofile_operations *ops) { } +static void mux_clone(int cpu) { } + +#endif + +static void free_msrs(void) +{ + int i; + for_each_possible_cpu(i) { + kfree(per_cpu(cpu_msrs, i).counters); + per_cpu(cpu_msrs, i).counters = NULL; + kfree(per_cpu(cpu_msrs, i).controls); + per_cpu(cpu_msrs, i).controls = NULL; + } + nmi_shutdown_mux(); +} + +static int allocate_msrs(void) +{ + 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_each_possible_cpu(i) { + per_cpu(cpu_msrs, i).counters = kzalloc(counters_size, + GFP_KERNEL); + if (!per_cpu(cpu_msrs, i).counters) + goto fail; + per_cpu(cpu_msrs, i).controls = kzalloc(controls_size, + GFP_KERNEL); + if (!per_cpu(cpu_msrs, i).controls) + goto fail; + } + + if (!nmi_setup_mux()) + goto fail; + + return 1; + +fail: + free_msrs(); + return 0; +} + +static void nmi_cpu_setup(void) +{ + int cpu = smp_processor_id(); + struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu); + + nmi_cpu_save_registers(msrs); + raw_spin_lock(&oprofilefs_lock); + model->setup_ctrs(model, msrs); + nmi_cpu_setup_mux(cpu, msrs); + raw_spin_unlock(&oprofilefs_lock); + per_cpu(saved_lvtpc, cpu) = apic_read(APIC_LVTPC); + apic_write(APIC_LVTPC, APIC_DM_NMI); +} + +static void nmi_cpu_restore_registers(struct op_msrs *msrs) +{ + struct op_msr *counters = msrs->counters; + struct op_msr *controls = msrs->controls; + unsigned int i; + + for (i = 0; i < model->num_controls; ++i) { + if (controls[i].addr) + wrmsrl(controls[i].addr, controls[i].saved); + } + + for (i = 0; i < model->num_counters; ++i) { + if (counters[i].addr) + wrmsrl(counters[i].addr, counters[i].saved); + } +} + +static void nmi_cpu_shutdown(void) +{ + unsigned int v; + int cpu = smp_processor_id(); + struct op_msrs *msrs = &per_cpu(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, per_cpu(saved_lvtpc, cpu)); + apic_write(APIC_LVTERR, v); + nmi_cpu_restore_registers(msrs); +} + +static int nmi_cpu_online(unsigned int cpu) +{ + local_irq_disable(); + if (nmi_enabled) + nmi_cpu_setup(); + if (ctr_running) + nmi_cpu_start(NULL); + local_irq_enable(); + return 0; +} + +static int nmi_cpu_down_prep(unsigned int cpu) +{ + local_irq_disable(); + if (ctr_running) + nmi_cpu_stop(NULL); + if (nmi_enabled) + nmi_cpu_shutdown(); + local_irq_enable(); + return 0; +} + +static int nmi_create_files(struct dentry *root) +{ + unsigned int i; + + for (i = 0; i < model->num_virt_counters; ++i) { + struct dentry *dir; + char buf[4]; + + /* quick little hack to _not_ expose a counter if it is not + * available for use. This should protect userspace app. + * NOTE: assumes 1:1 mapping here (that counters are organized + * sequentially in their struct assignment). + */ + if (!avail_to_resrv_perfctr_nmi_bit(op_x86_virt_to_phys(i))) + continue; + + snprintf(buf, sizeof(buf), "%d", i); + dir = oprofilefs_mkdir(root, buf); + oprofilefs_create_ulong(dir, "enabled", &counter_config[i].enabled); + oprofilefs_create_ulong(dir, "event", &counter_config[i].event); + oprofilefs_create_ulong(dir, "count", &counter_config[i].count); + oprofilefs_create_ulong(dir, "unit_mask", &counter_config[i].unit_mask); + oprofilefs_create_ulong(dir, "kernel", &counter_config[i].kernel); + oprofilefs_create_ulong(dir, "user", &counter_config[i].user); + oprofilefs_create_ulong(dir, "extra", &counter_config[i].extra); + } + + return 0; +} + +static enum cpuhp_state cpuhp_nmi_online; + +static int nmi_setup(void) +{ + int err = 0; + int cpu; + + if (!allocate_msrs()) + return -ENOMEM; + + /* We need to serialize save and setup for HT because the subset + * of msrs are distinct for save and setup operations + */ + + /* Assume saved/restored counters are the same on all CPUs */ + err = model->fill_in_addresses(&per_cpu(cpu_msrs, 0)); + if (err) + goto fail; + + for_each_possible_cpu(cpu) { + if (!IS_ENABLED(CONFIG_SMP) || !cpu) + continue; + + memcpy(per_cpu(cpu_msrs, cpu).counters, + per_cpu(cpu_msrs, 0).counters, + sizeof(struct op_msr) * model->num_counters); + + memcpy(per_cpu(cpu_msrs, cpu).controls, + per_cpu(cpu_msrs, 0).controls, + sizeof(struct op_msr) * model->num_controls); + + mux_clone(cpu); + } + + nmi_enabled = 0; + ctr_running = 0; + /* make variables visible to the nmi handler: */ + smp_mb(); + err = register_nmi_handler(NMI_LOCAL, profile_exceptions_notify, + 0, "oprofile"); + if (err) + goto fail; + + nmi_enabled = 1; + /* make nmi_enabled visible to the nmi handler: */ + smp_mb(); + err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/oprofile:online", + nmi_cpu_online, nmi_cpu_down_prep); + if (err < 0) + goto fail_nmi; + cpuhp_nmi_online = err; + return 0; +fail_nmi: + unregister_nmi_handler(NMI_LOCAL, "oprofile"); +fail: + free_msrs(); + return err; +} + +static void nmi_shutdown(void) +{ + struct op_msrs *msrs; + + cpuhp_remove_state(cpuhp_nmi_online); + nmi_enabled = 0; + ctr_running = 0; + + /* make variables visible to the nmi handler: */ + smp_mb(); + unregister_nmi_handler(NMI_LOCAL, "oprofile"); + msrs = &get_cpu_var(cpu_msrs); + model->shutdown(msrs); + free_msrs(); + put_cpu_var(cpu_msrs); +} + +#ifdef CONFIG_PM + +static int nmi_suspend(void) +{ + /* Only one CPU left, just stop that one */ + if (nmi_enabled == 1) + nmi_cpu_stop(NULL); + return 0; +} + +static void nmi_resume(void) +{ + if (nmi_enabled == 1) + nmi_cpu_start(NULL); +} + +static struct syscore_ops oprofile_syscore_ops = { + .resume = nmi_resume, + .suspend = nmi_suspend, +}; + +static void __init init_suspend_resume(void) +{ + register_syscore_ops(&oprofile_syscore_ops); +} + +static void exit_suspend_resume(void) +{ + unregister_syscore_ops(&oprofile_syscore_ops); +} + +#else + +static inline void init_suspend_resume(void) { } +static inline void exit_suspend_resume(void) { } + +#endif /* CONFIG_PM */ + +static int __init p4_init(char **cpu_type) +{ + __u8 cpu_model = boot_cpu_data.x86_model; + + if (cpu_model > 6 || cpu_model == 5) + 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; +} + +enum __force_cpu_type { + reserved = 0, /* do not force */ + timer, + arch_perfmon, +}; + +static int force_cpu_type; + +static int set_cpu_type(const char *str, const struct kernel_param *kp) +{ + if (!strcmp(str, "timer")) { + force_cpu_type = timer; + printk(KERN_INFO "oprofile: forcing NMI timer mode\n"); + } else if (!strcmp(str, "arch_perfmon")) { + force_cpu_type = arch_perfmon; + printk(KERN_INFO "oprofile: forcing architectural perfmon\n"); + } else { + force_cpu_type = 0; + } + + return 0; +} +module_param_call(cpu_type, set_cpu_type, NULL, NULL, 0); + +static int __init ppro_init(char **cpu_type) +{ + __u8 cpu_model = boot_cpu_data.x86_model; + struct op_x86_model_spec *spec = &op_ppro_spec; /* default */ + + if (force_cpu_type == arch_perfmon && boot_cpu_has(X86_FEATURE_ARCH_PERFMON)) + return 0; + + /* + * Documentation on identifying Intel processors by CPU family + * and model can be found in the Intel Software Developer's + * Manuals (SDM): + * + * http://www.intel.com/products/processor/manuals/ + * + * As of May 2010 the documentation for this was in the: + * "Intel 64 and IA-32 Architectures Software Developer's + * Manual Volume 3B: System Programming Guide", "Table B-1 + * CPUID Signature Values of DisplayFamily_DisplayModel". + */ + switch (cpu_model) { + case 0 ... 2: + *cpu_type = "i386/ppro"; + break; + case 3 ... 5: + *cpu_type = "i386/pii"; + break; + case 6 ... 8: + case 10 ... 11: + *cpu_type = "i386/piii"; + break; + case 9: + case 13: + *cpu_type = "i386/p6_mobile"; + break; + case 14: + *cpu_type = "i386/core"; + break; + case 0x0f: + case 0x16: + case 0x17: + case 0x1d: + *cpu_type = "i386/core_2"; + break; + case 0x1a: + case 0x1e: + case 0x2e: + spec = &op_arch_perfmon_spec; + *cpu_type = "i386/core_i7"; + break; + case 0x1c: + *cpu_type = "i386/atom"; + break; + default: + /* Unknown */ + return 0; + } + + model = spec; + return 1; +} + +int __init op_nmi_init(struct oprofile_operations *ops) +{ + __u8 vendor = boot_cpu_data.x86_vendor; + __u8 family = boot_cpu_data.x86; + char *cpu_type = NULL; + int ret = 0; + + if (!boot_cpu_has(X86_FEATURE_APIC)) + return -ENODEV; + + if (force_cpu_type == timer) + return -ENODEV; + + switch (vendor) { + case X86_VENDOR_AMD: + /* Needs to be at least an Athlon (or hammer in 32bit mode) */ + + switch (family) { + case 6: + cpu_type = "i386/athlon"; + break; + case 0xf: + /* + * Actually it could be i386/hammer too, but + * give user space an consistent name. + */ + cpu_type = "x86-64/hammer"; + break; + case 0x10: + cpu_type = "x86-64/family10"; + break; + case 0x11: + cpu_type = "x86-64/family11h"; + break; + case 0x12: + cpu_type = "x86-64/family12h"; + break; + case 0x14: + cpu_type = "x86-64/family14h"; + break; + case 0x15: + cpu_type = "x86-64/family15h"; + break; + default: + return -ENODEV; + } + model = &op_amd_spec; + break; + + case X86_VENDOR_INTEL: + switch (family) { + /* Pentium IV */ + case 0xf: + p4_init(&cpu_type); + break; + + /* A P6-class processor */ + case 6: + ppro_init(&cpu_type); + break; + + default: + break; + } + + if (cpu_type) + break; + + if (!boot_cpu_has(X86_FEATURE_ARCH_PERFMON)) + return -ENODEV; + + /* use arch perfmon as fallback */ + cpu_type = "i386/arch_perfmon"; + model = &op_arch_perfmon_spec; + break; + + default: + return -ENODEV; + } + + /* default values, can be overwritten by model */ + 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; + + if (model->init) + ret = model->init(ops); + if (ret) + return ret; + + if (!model->num_virt_counters) + model->num_virt_counters = model->num_counters; + + mux_init(ops); + + init_suspend_resume(); + + printk(KERN_INFO "oprofile: using NMI interrupt.\n"); + return 0; +} + +void op_nmi_exit(void) +{ + exit_suspend_resume(); +} |