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Diffstat (limited to 'arch/x86/oprofile/nmi_int.c')
-rw-r--r--arch/x86/oprofile/nmi_int.c780
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();
+}