arch/x86/oprofile/nmi_int.c - maze/linux - Git at Google

 /**
  * @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 |= (event & 0x0F00) << 24;

 	return val;
 }


 static int profile_exceptions_notify(unsigned int val, struct pt_regs *regs)
 {
 	if (ctr_running)
 		model->check_ctrs(regs, &__get_cpu_var(cpu_msrs));
 	else if (!nmi_enabled)
 		return NMI_DONE;
 	else
 		model->stop(&__get_cpu_var(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 = &__get_cpu_var(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 = &__get_cpu_var(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 *dummy)
 {
 	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 *dummy)
 {
 	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 void nmi_cpu_up(void *dummy)
 {
 	if (nmi_enabled)
 		nmi_cpu_setup(dummy);
 	if (ctr_running)
 		nmi_cpu_start(dummy);
 }

 static void nmi_cpu_down(void *dummy)
 {
 	if (ctr_running)
 		nmi_cpu_stop(dummy);
 	if (nmi_enabled)
 		nmi_cpu_shutdown(dummy);
 }

 static int nmi_create_files(struct super_block *sb, 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(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);
 		oprofilefs_create_ulong(sb, dir, "extra", &counter_config[i].extra);
 	}

 	return 0;
 }

 static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action,
 				 void *data)
 {
 	int cpu = (unsigned long)data;
 	switch (action) {
 	case CPU_DOWN_FAILED:
 	case CPU_ONLINE:
 		smp_call_function_single(cpu, nmi_cpu_up, NULL, 0);
 		break;
 	case CPU_DOWN_PREPARE:
 		smp_call_function_single(cpu, nmi_cpu_down, NULL, 1);
 		break;
 	}
 	return NOTIFY_DONE;
 }

 static struct notifier_block oprofile_cpu_nb = {
 	.notifier_call = oprofile_cpu_notifier
 };

 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 (!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;

 	get_online_cpus();
 	register_cpu_notifier(&oprofile_cpu_nb);
 	nmi_enabled = 1;
 	/* make nmi_enabled visible to the nmi handler: */
 	smp_mb();
 	on_each_cpu(nmi_cpu_setup, NULL, 1);
 	put_online_cpus();

 	return 0;
 fail:
 	free_msrs();
 	return err;
 }

 static void nmi_shutdown(void)
 {
 	struct op_msrs *msrs;

 	get_online_cpus();
 	unregister_cpu_notifier(&oprofile_cpu_nb);
 	on_each_cpu(nmi_cpu_shutdown, NULL, 1);
 	nmi_enabled = 0;
 	ctr_running = 0;
 	put_online_cpus();
 	/* 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, 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 && cpu_has_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 (!cpu_has_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 (!cpu_has_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();
 }
	/**
	* @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 \|= (event & 0x0F00) << 24;

	return val;
	}


	static int profile_exceptions_notify(unsigned int val, struct pt_regs *regs)
	{
	if (ctr_running)
	model->check_ctrs(regs, &__get_cpu_var(cpu_msrs));
	else if (!nmi_enabled)
	return NMI_DONE;
	else
	model->stop(&__get_cpu_var(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 = &__get_cpu_var(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 = &__get_cpu_var(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 *dummy)
	{
	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 *dummy)
	{
	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 void nmi_cpu_up(void *dummy)
	{
	if (nmi_enabled)
	nmi_cpu_setup(dummy);
	if (ctr_running)
	nmi_cpu_start(dummy);
	}

	static void nmi_cpu_down(void *dummy)
	{
	if (ctr_running)
	nmi_cpu_stop(dummy);
	if (nmi_enabled)
	nmi_cpu_shutdown(dummy);
	}

	static int nmi_create_files(struct super_block sb, 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(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);
	oprofilefs_create_ulong(sb, dir, "extra", &counter_config[i].extra);
	}

	return 0;
	}

	static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action,
	void *data)
	{
	int cpu = (unsigned long)data;
	switch (action) {
	case CPU_DOWN_FAILED:
	case CPU_ONLINE:
	smp_call_function_single(cpu, nmi_cpu_up, NULL, 0);
	break;
	case CPU_DOWN_PREPARE:
	smp_call_function_single(cpu, nmi_cpu_down, NULL, 1);
	break;
	}
	return NOTIFY_DONE;
	}

	static struct notifier_block oprofile_cpu_nb = {
	.notifier_call = oprofile_cpu_notifier
	};

	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 (!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;

	get_online_cpus();
	register_cpu_notifier(&oprofile_cpu_nb);
	nmi_enabled = 1;
	/* make nmi_enabled visible to the nmi handler: */
	smp_mb();
	on_each_cpu(nmi_cpu_setup, NULL, 1);
	put_online_cpus();

	return 0;
	fail:
	free_msrs();
	return err;
	}

	static void nmi_shutdown(void)
	{
	struct op_msrs *msrs;

	get_online_cpus();
	unregister_cpu_notifier(&oprofile_cpu_nb);
	on_each_cpu(nmi_cpu_shutdown, NULL, 1);
	nmi_enabled = 0;
	ctr_running = 0;
	put_online_cpus();
	/* 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, 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 && cpu_has_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 (!cpu_has_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 (!cpu_has_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();
	}