/* * @file op_model_ppro.h * Family 6 perfmon and architectural perfmon MSR operations * * @remark Copyright 2002 OProfile authors * @remark Copyright 2008 Intel Corporation * @remark Read the file COPYING * * @author John Levon * @author Philippe Elie * @author Graydon Hoare * @author Andi Kleen */ #include <linux/oprofile.h> #include <linux/slab.h> #include <asm/ptrace.h> #include <asm/msr.h> #include <asm/apic.h> #include <asm/nmi.h> #include <asm/intel_arch_perfmon.h> #include "op_x86_model.h" #include "op_counter.h" static int num_counters = 2; static int counter_width = 32; #define CTR_IS_RESERVED(msrs, c) (msrs->counters[(c)].addr ? 1 : 0) #define CTR_OVERFLOWED(n) (!((n) & (1ULL<<(counter_width-1)))) #define CTRL_IS_RESERVED(msrs, c) (msrs->controls[(c)].addr ? 1 : 0) #define CTRL_READ(l, h, msrs, c) do {rdmsr((msrs->controls[(c)].addr), (l), (h)); } while (0) #define CTRL_WRITE(l, h, msrs, c) do {wrmsr((msrs->controls[(c)].addr), (l), (h)); } while (0) #define CTRL_SET_ACTIVE(n) (n |= (1<<22)) #define CTRL_SET_INACTIVE(n) (n &= ~(1<<22)) #define CTRL_CLEAR(x) (x &= (1<<21)) #define CTRL_SET_ENABLE(val) (val |= 1<<20) #define CTRL_SET_USR(val, u) (val |= ((u & 1) << 16)) #define CTRL_SET_KERN(val, k) (val |= ((k & 1) << 17)) #define CTRL_SET_UM(val, m) (val |= (m << 8)) #define CTRL_SET_EVENT(val, e) (val |= e) static u64 *reset_value; static void ppro_fill_in_addresses(struct op_msrs * const msrs) { int i; for (i = 0; i < num_counters; i++) { if (reserve_perfctr_nmi(MSR_P6_PERFCTR0 + i)) msrs->counters[i].addr = MSR_P6_PERFCTR0 + i; else msrs->counters[i].addr = 0; } for (i = 0; i < num_counters; i++) { if (reserve_evntsel_nmi(MSR_P6_EVNTSEL0 + i)) msrs->controls[i].addr = MSR_P6_EVNTSEL0 + i; else msrs->controls[i].addr = 0; } } static void ppro_setup_ctrs(struct op_msrs const * const msrs) { unsigned int low, high; int i; if (!reset_value) { reset_value = kmalloc(sizeof(reset_value[0]) * num_counters, GFP_ATOMIC); if (!reset_value) return; } if (cpu_has_arch_perfmon) { union cpuid10_eax eax; eax.full = cpuid_eax(0xa); if (counter_width < eax.split.bit_width) counter_width = eax.split.bit_width; } /* clear all counters */ for (i = 0 ; i < num_counters; ++i) { if (unlikely(!CTRL_IS_RESERVED(msrs, i))) continue; CTRL_READ(low, high, msrs, i); CTRL_CLEAR(low); CTRL_WRITE(low, high, msrs, i); } /* avoid a false detection of ctr overflows in NMI handler */ for (i = 0; i < num_counters; ++i) { if (unlikely(!CTR_IS_RESERVED(msrs, i))) continue; wrmsrl(msrs->counters[i].addr, -1LL); } /* enable active counters */ for (i = 0; i < num_counters; ++i) { if ((counter_config[i].enabled) && (CTR_IS_RESERVED(msrs, i))) { reset_value[i] = counter_config[i].count; wrmsrl(msrs->counters[i].addr, -reset_value[i]); CTRL_READ(low, high, msrs, i); CTRL_CLEAR(low); CTRL_SET_ENABLE(low); CTRL_SET_USR(low, counter_config[i].user); CTRL_SET_KERN(low, counter_config[i].kernel); CTRL_SET_UM(low, counter_config[i].unit_mask); CTRL_SET_EVENT(low, counter_config[i].event); CTRL_WRITE(low, high, msrs, i); } else { reset_value[i] = 0; } } } static int ppro_check_ctrs(struct pt_regs * const regs, struct op_msrs const * const msrs) { u64 val; int i; for (i = 0 ; i < num_counters; ++i) { if (!reset_value[i]) continue; rdmsrl(msrs->counters[i].addr, val); if (CTR_OVERFLOWED(val)) { oprofile_add_sample(regs, i); wrmsrl(msrs->counters[i].addr, -reset_value[i]); } } /* Only P6 based Pentium M need to re-unmask the apic vector but it * doesn't hurt other P6 variant */ apic_write(APIC_LVTPC, apic_read(APIC_LVTPC) & ~APIC_LVT_MASKED); /* We can't work out if we really handled an interrupt. We * might have caught a *second* counter just after overflowing * the interrupt for this counter then arrives * and we don't find a counter that's overflowed, so we * would return 0 and get dazed + confused. Instead we always * assume we found an overflow. This sucks. */ return 1; } static void ppro_start(struct op_msrs const * const msrs) { unsigned int low, high; int i; if (!reset_value) return; for (i = 0; i < num_counters; ++i) { if (reset_value[i]) { CTRL_READ(low, high, msrs, i); CTRL_SET_ACTIVE(low); CTRL_WRITE(low, high, msrs, i); } } } static void ppro_stop(struct op_msrs const * const msrs) { unsigned int low, high; int i; if (!reset_value) return; for (i = 0; i < num_counters; ++i) { if (!reset_value[i]) continue; CTRL_READ(low, high, msrs, i); CTRL_SET_INACTIVE(low); CTRL_WRITE(low, high, msrs, i); } } static void ppro_shutdown(struct op_msrs const * const msrs) { int i; for (i = 0 ; i < num_counters ; ++i) { if (CTR_IS_RESERVED(msrs, i)) release_perfctr_nmi(MSR_P6_PERFCTR0 + i); } for (i = 0 ; i < num_counters ; ++i) { if (CTRL_IS_RESERVED(msrs, i)) release_evntsel_nmi(MSR_P6_EVNTSEL0 + i); } if (reset_value) { kfree(reset_value); reset_value = NULL; } } struct op_x86_model_spec op_ppro_spec = { .num_counters = 2, /* can be overriden */ .num_controls = 2, /* dito */ .fill_in_addresses = &ppro_fill_in_addresses, .setup_ctrs = &ppro_setup_ctrs, .check_ctrs = &ppro_check_ctrs, .start = &ppro_start, .stop = &ppro_stop, .shutdown = &ppro_shutdown }; /* * Architectural performance monitoring. * * Newer Intel CPUs (Core1+) have support for architectural * events described in CPUID 0xA. See the IA32 SDM Vol3b.18 for details. * The advantage of this is that it can be done without knowing about * the specific CPU. */ void arch_perfmon_setup_counters(void) { union cpuid10_eax eax; eax.full = cpuid_eax(0xa); /* Workaround for BIOS bugs in 6/15. Taken from perfmon2 */ if (eax.split.version_id == 0 && current_cpu_data.x86 == 6 && current_cpu_data.x86_model == 15) { eax.split.version_id = 2; eax.split.num_counters = 2; eax.split.bit_width = 40; } num_counters = eax.split.num_counters; op_arch_perfmon_spec.num_counters = num_counters; op_arch_perfmon_spec.num_controls = num_counters; op_ppro_spec.num_counters = num_counters; op_ppro_spec.num_controls = num_counters; } struct op_x86_model_spec op_arch_perfmon_spec = { /* num_counters/num_controls filled in at runtime */ .fill_in_addresses = &ppro_fill_in_addresses, /* user space does the cpuid check for available events */ .setup_ctrs = &ppro_setup_ctrs, .check_ctrs = &ppro_check_ctrs, .start = &ppro_start, .stop = &ppro_stop, .shutdown = &ppro_shutdown };