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Diffstat (limited to 'arch/i386/oprofile/nmi_int.c')
-rw-r--r--arch/i386/oprofile/nmi_int.c427
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();
+}