[apple/xnu.git] / osfmk / x86_64 / kpc_x86.c

/*
 * Copyright (c) 2012 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

#include <mach/mach_types.h>
#include <machine/machine_routines.h>
#include <kern/processor.h>
#include <i386/cpuid.h>
#include <i386/proc_reg.h>
#include <i386/mp.h>
#include <sys/errno.h>
#include <kperf/buffer.h>

#include <kern/kpc.h>

#include <kperf/kperf.h>
#include <kperf/sample.h>
#include <kperf/context.h>
#include <kperf/action.h>

#include <kern/monotonic.h>

/* Fixed counter mask -- three counters, each with OS and USER */
#define IA32_FIXED_CTR_ENABLE_ALL_CTRS_ALL_RINGS (0x333)
#define IA32_FIXED_CTR_ENABLE_ALL_PMI (0x888)

#define IA32_PERFEVT_USER_EN (0x10000)
#define IA32_PERFEVT_OS_EN (0x20000)

#define IA32_PERFEVTSEL_PMI (1ull << 20)
#define IA32_PERFEVTSEL_EN (1ull << 22)

/* Non-serialising */
#define USE_RDPMC

#define RDPMC_FIXED_COUNTER_SELECTOR (1ULL<<30)

/* track the last config we enabled */
static uint64_t kpc_running_cfg_pmc_mask = 0;
static uint32_t kpc_running_classes = 0;

/* PMC / MSR accesses */

static uint64_t
IA32_FIXED_CTR_CTRL(void)
{
        return rdmsr64( MSR_IA32_PERF_FIXED_CTR_CTRL );
}

#ifdef FIXED_COUNTER_RELOAD
static void
wrIA32_FIXED_CTRx(uint32_t ctr, uint64_t value)
{
        return wrmsr64(MSR_IA32_PERF_FIXED_CTR0 + ctr, value);
}
#endif

static uint64_t
IA32_PMCx(uint32_t ctr)
{
#ifdef USE_RDPMC
        return rdpmc64(ctr);
#else /* !USE_RDPMC */
        return rdmsr64(MSR_IA32_PERFCTR0 + ctr);
#endif /* !USE_RDPMC */
}

static void
wrIA32_PMCx(uint32_t ctr, uint64_t value)
{
        return wrmsr64(MSR_IA32_PERFCTR0 + ctr, value);
}

static uint64_t
IA32_PERFEVTSELx(uint32_t ctr)
{
        return rdmsr64(MSR_IA32_EVNTSEL0 + ctr);
}

static void
wrIA32_PERFEVTSELx(uint32_t ctr, uint64_t value)
{
        wrmsr64(MSR_IA32_EVNTSEL0 + ctr, value);
}


/* internal functions */

boolean_t
kpc_is_running_fixed(void)
{
        return (kpc_running_classes & KPC_CLASS_FIXED_MASK) == KPC_CLASS_FIXED_MASK;
}

boolean_t
kpc_is_running_configurable(uint64_t pmc_mask)
{
        assert(kpc_popcount(pmc_mask) <= kpc_configurable_count());
        return ((kpc_running_classes & KPC_CLASS_CONFIGURABLE_MASK) == KPC_CLASS_CONFIGURABLE_MASK) &&
               ((kpc_running_cfg_pmc_mask & pmc_mask) == pmc_mask);
}

uint32_t
kpc_fixed_count(void)
{
        i386_cpu_info_t *info = NULL;
        info = cpuid_info();
        return info->cpuid_arch_perf_leaf.fixed_number;
}

uint32_t
kpc_configurable_count(void)
{
        i386_cpu_info_t *info = NULL;
        info = cpuid_info();
        return info->cpuid_arch_perf_leaf.number;
}

uint32_t
kpc_fixed_config_count(void)
{
        return KPC_X86_64_FIXED_CONFIGS;
}

uint32_t
kpc_configurable_config_count(uint64_t pmc_mask)
{
        assert(kpc_popcount(pmc_mask) <= kpc_configurable_count());
        return kpc_popcount(pmc_mask);
}

uint32_t
kpc_rawpmu_config_count(void)
{
        // RAW PMU access not implemented.
        return 0;
}

int
kpc_get_rawpmu_config(__unused kpc_config_t *configv)
{
        return 0;
}

static uint8_t
kpc_fixed_width(void)
{
        i386_cpu_info_t *info = NULL;

        info = cpuid_info();

        return info->cpuid_arch_perf_leaf.fixed_width;
}

static uint8_t
kpc_configurable_width(void)
{
        i386_cpu_info_t *info = NULL;

        info = cpuid_info();

        return info->cpuid_arch_perf_leaf.width;
}

uint64_t
kpc_fixed_max(void)
{
        return (1ULL << kpc_fixed_width()) - 1;
}

uint64_t
kpc_configurable_max(void)
{
        return (1ULL << kpc_configurable_width()) - 1;
}

#ifdef FIXED_COUNTER_SHADOW
static uint64_t
kpc_reload_fixed(int ctr)
{
        uint64_t old = IA32_FIXED_CTRx(ctr);
        wrIA32_FIXED_CTRx(ctr, FIXED_RELOAD(ctr));
        return old;
}
#endif

static uint64_t
kpc_reload_configurable(int ctr)
{
        uint64_t cfg = IA32_PERFEVTSELx(ctr);

        /* counters must be disabled before they can be written to */
        uint64_t old = IA32_PMCx(ctr);
        wrIA32_PERFEVTSELx(ctr, cfg & ~IA32_PERFEVTSEL_EN);
        wrIA32_PMCx(ctr, CONFIGURABLE_RELOAD(ctr));
        wrIA32_PERFEVTSELx(ctr, cfg);
        return old;
}

void kpc_pmi_handler(void);

static void
set_running_fixed(boolean_t on)
{
        uint64_t global = 0, mask = 0, fixed_ctrl = 0;
        int i;
        boolean_t enabled;

        if (on) {
                /* these are per-thread in SMT */
                fixed_ctrl = IA32_FIXED_CTR_ENABLE_ALL_CTRS_ALL_RINGS | IA32_FIXED_CTR_ENABLE_ALL_PMI;
        } else {
                /* don't allow disabling fixed counters */
                return;
        }

        wrmsr64( MSR_IA32_PERF_FIXED_CTR_CTRL, fixed_ctrl );

        enabled = ml_set_interrupts_enabled(FALSE);

        /* rmw the global control */
        global = rdmsr64(MSR_IA32_PERF_GLOBAL_CTRL);
        for (i = 0; i < (int) kpc_fixed_count(); i++) {
                mask |= (1ULL << (32 + i));
        }

        if (on) {
                global |= mask;
        } else {
                global &= ~mask;
        }

        wrmsr64(MSR_IA32_PERF_GLOBAL_CTRL, global);

        ml_set_interrupts_enabled(enabled);
}

static void
set_running_configurable(uint64_t target_mask, uint64_t state_mask)
{
        uint32_t cfg_count = kpc_configurable_count();
        uint64_t global = 0ULL, cfg = 0ULL, save = 0ULL;
        boolean_t enabled;

        enabled = ml_set_interrupts_enabled(FALSE);

        /* rmw the global control */
        global = rdmsr64(MSR_IA32_PERF_GLOBAL_CTRL);

        /* need to save and restore counter since it resets when reconfigured */
        for (uint32_t i = 0; i < cfg_count; ++i) {
                cfg = IA32_PERFEVTSELx(i);
                save = IA32_PMCx(i);
                wrIA32_PERFEVTSELx(i, cfg | IA32_PERFEVTSEL_PMI | IA32_PERFEVTSEL_EN);
                wrIA32_PMCx(i, save);
        }

        /* update the global control value */
        global &= ~target_mask; /* clear the targeted PMCs bits */
        global |= state_mask;   /* update the targeted PMCs bits with their new states */
        wrmsr64(MSR_IA32_PERF_GLOBAL_CTRL, global);

        ml_set_interrupts_enabled(enabled);
}

static void
kpc_set_running_mp_call( void *vstate )
{
        struct kpc_running_remote *mp_config = (struct kpc_running_remote*) vstate;
        assert(mp_config);

        if (kpc_controls_fixed_counters()) {
                set_running_fixed(mp_config->classes & KPC_CLASS_FIXED_MASK);
        }

        set_running_configurable(mp_config->cfg_target_mask,
            mp_config->cfg_state_mask);
}

int
kpc_get_fixed_config(kpc_config_t *configv)
{
        configv[0] = IA32_FIXED_CTR_CTRL();
        return 0;
}

static int
kpc_set_fixed_config(kpc_config_t *configv)
{
        (void) configv;

        /* NYI */
        return -1;
}

int
kpc_get_fixed_counters(uint64_t *counterv)
{
#if MONOTONIC
        mt_fixed_counts(counterv);
        return 0;
#else /* MONOTONIC */
#pragma unused(counterv)
        return ENOTSUP;
#endif /* !MONOTONIC */
}

int
kpc_get_configurable_config(kpc_config_t *configv, uint64_t pmc_mask)
{
        uint32_t cfg_count = kpc_configurable_count();

        assert(configv);

        for (uint32_t i = 0; i < cfg_count; ++i) {
                if ((1ULL << i) & pmc_mask) {
                        *configv++  = IA32_PERFEVTSELx(i);
                }
        }
        return 0;
}

static int
kpc_set_configurable_config(kpc_config_t *configv, uint64_t pmc_mask)
{
        uint32_t cfg_count = kpc_configurable_count();
        uint64_t save;

        for (uint32_t i = 0; i < cfg_count; i++) {
                if (((1ULL << i) & pmc_mask) == 0) {
                        continue;
                }

                /* need to save and restore counter since it resets when reconfigured */
                save = IA32_PMCx(i);

                /*
                 * Some bits are not safe to set from user space.
                 * Allow these bits to be set:
                 *
                 *   0-7    Event select
                 *   8-15   UMASK
                 *   16     USR
                 *   17     OS
                 *   18     E
                 *   22     EN
                 *   23     INV
                 *   24-31  CMASK
                 *
                 * Excluding:
                 *
                 *   19     PC
                 *   20     INT
                 *   21     AnyThread
                 *   32     IN_TX
                 *   33     IN_TXCP
                 *   34-63  Reserved
                 */
                wrIA32_PERFEVTSELx(i, *configv & 0xffc7ffffull);
                wrIA32_PMCx(i, save);

                /* next configuration word */
                configv++;
        }

        return 0;
}

int
kpc_get_configurable_counters(uint64_t *counterv, uint64_t pmc_mask)
{
        uint32_t cfg_count = kpc_configurable_count();
        uint64_t status, *it_counterv = counterv;

        /* snap the counters */
        for (uint32_t i = 0; i < cfg_count; ++i) {
                if ((1ULL << i) & pmc_mask) {
                        *it_counterv++ = CONFIGURABLE_SHADOW(i) +
                            (IA32_PMCx(i) - CONFIGURABLE_RELOAD(i));
                }
        }

        /* Grab the overflow bits */
        status = rdmsr64(MSR_IA32_PERF_GLOBAL_STATUS);

        /* reset the iterator */
        it_counterv = counterv;

        /*
         * If the overflow bit is set for a counter, our previous read may or may not have been
         * before the counter overflowed. Re-read any counter with it's overflow bit set so
         * we know for sure that it has overflowed. The reason this matters is that the math
         * is different for a counter that has overflowed.
         */
        for (uint32_t i = 0; i < cfg_count; ++i) {
                if (((1ULL << i) & pmc_mask) &&
                    ((1ULL << i) & status)) {
                        *it_counterv++ = CONFIGURABLE_SHADOW(i) +
                            (kpc_configurable_max() - CONFIGURABLE_RELOAD(i)) + IA32_PMCx(i);
                }
        }

        return 0;
}

static void
kpc_get_curcpu_counters_mp_call(void *args)
{
        struct kpc_get_counters_remote *handler = args;
        int offset = 0, r = 0;

        assert(handler);
        assert(handler->buf);

        offset = cpu_number() * handler->buf_stride;
        r = kpc_get_curcpu_counters(handler->classes, NULL, &handler->buf[offset]);

        /* number of counters added by this CPU, needs to be atomic  */
        os_atomic_add(&(handler->nb_counters), r, relaxed);
}

int
kpc_get_all_cpus_counters(uint32_t classes, int *curcpu, uint64_t *buf)
{
        int enabled = 0;

        struct kpc_get_counters_remote hdl = {
                .classes = classes, .nb_counters = 0,
                .buf_stride = kpc_get_counter_count(classes), .buf = buf
        };

        assert(buf);

        enabled = ml_set_interrupts_enabled(FALSE);

        if (curcpu) {
                *curcpu = cpu_number();
        }
        mp_cpus_call(CPUMASK_ALL, ASYNC, kpc_get_curcpu_counters_mp_call, &hdl);

        ml_set_interrupts_enabled(enabled);

        return hdl.nb_counters;
}

static void
kpc_set_config_mp_call(void *vmp_config)
{
        struct kpc_config_remote *mp_config = vmp_config;
        kpc_config_t *new_config = NULL;
        uint32_t classes = 0, count = 0;
        boolean_t enabled;

        assert(mp_config);
        assert(mp_config->configv);
        classes = mp_config->classes;
        new_config = mp_config->configv;

        enabled = ml_set_interrupts_enabled(FALSE);

        if (classes & KPC_CLASS_FIXED_MASK) {
                kpc_set_fixed_config(&new_config[count]);
                count += kpc_get_config_count(KPC_CLASS_FIXED_MASK);
        }

        if (classes & KPC_CLASS_CONFIGURABLE_MASK) {
                kpc_set_configurable_config(&new_config[count], mp_config->pmc_mask);
                count += kpc_popcount(mp_config->pmc_mask);
        }

        ml_set_interrupts_enabled(enabled);
}

static void
kpc_set_reload_mp_call(void *vmp_config)
{
        struct kpc_config_remote *mp_config = vmp_config;
        uint64_t *new_period = NULL, max = kpc_configurable_max();
        uint32_t classes = 0, count = 0;
        boolean_t enabled;

        assert(mp_config);
        assert(mp_config->configv);
        classes = mp_config->classes;
        new_period = mp_config->configv;

        enabled = ml_set_interrupts_enabled(FALSE);

        if (classes & KPC_CLASS_CONFIGURABLE_MASK) {
                /*
                 * Update _all_ shadow counters, this cannot be done for only
                 * selected PMCs. Otherwise, we would corrupt the configurable
                 * shadow buffer since the PMCs are muxed according to the pmc
                 * mask.
                 */
                uint64_t all_cfg_mask = (1ULL << kpc_configurable_count()) - 1;
                kpc_get_configurable_counters(&CONFIGURABLE_SHADOW(0), all_cfg_mask);

                /* set the new period */
                count = kpc_configurable_count();
                for (uint32_t i = 0; i < count; ++i) {
                        /* ignore the counter */
                        if (((1ULL << i) & mp_config->pmc_mask) == 0) {
                                continue;
                        }

                        if (*new_period == 0) {
                                *new_period = kpc_configurable_max();
                        }

                        CONFIGURABLE_RELOAD(i) = max - *new_period;

                        /* reload the counter */
                        kpc_reload_configurable(i);

                        /* clear overflow bit just in case */
                        wrmsr64(MSR_IA32_PERF_GLOBAL_OVF_CTRL, 1ull << i);

                        /* next period value */
                        new_period++;
                }
        }

        ml_set_interrupts_enabled(enabled);
}

int
kpc_set_period_arch( struct kpc_config_remote *mp_config )
{
        mp_cpus_call( CPUMASK_ALL, ASYNC, kpc_set_reload_mp_call, mp_config );

        return 0;
}


/* interface functions */

void
kpc_arch_init(void)
{
        i386_cpu_info_t *info = cpuid_info();
        uint8_t version_id = info->cpuid_arch_perf_leaf.version;
        /*
         * kpc only supports Intel PMU versions 2 and above.
         */
        if (version_id < 2) {
                kpc_supported = false;
        }
}

uint32_t
kpc_get_classes(void)
{
        return KPC_CLASS_FIXED_MASK | KPC_CLASS_CONFIGURABLE_MASK;
}

int
kpc_set_running_arch(struct kpc_running_remote *mp_config)
{
        assert(mp_config);

        /* dispatch to all CPUs */
        mp_cpus_call(CPUMASK_ALL, ASYNC, kpc_set_running_mp_call, mp_config);

        kpc_running_cfg_pmc_mask = mp_config->cfg_state_mask;
        kpc_running_classes = mp_config->classes;

        return 0;
}

int
kpc_set_config_arch(struct kpc_config_remote *mp_config)
{
        mp_cpus_call( CPUMASK_ALL, ASYNC, kpc_set_config_mp_call, mp_config );

        return 0;
}

static uintptr_t
get_interrupted_pc(bool *kernel_out)
{
        x86_saved_state_t *state = current_cpu_datap()->cpu_int_state;
        if (!state) {
                return 0;
        }

        bool state_64 = is_saved_state64(state);
        uint64_t cs;
        if (state_64) {
                cs = saved_state64(state)->isf.cs;
        } else {
                cs = saved_state32(state)->cs;
        }
        bool kernel = (cs & SEL_PL) != SEL_PL_U;
        *kernel_out = kernel;

        uintptr_t pc = 0;
        if (state_64) {
                pc = saved_state64(state)->isf.rip;
        } else {
                pc = saved_state32(state)->eip;
        }
        if (kernel) {
                pc = VM_KERNEL_UNSLIDE(pc);
        }
        return pc;
}

static void
kpc_sample_kperf_x86(uint32_t ctr, uint64_t count, uint64_t config)
{
        uint32_t actionid = FIXED_ACTIONID(ctr);
        bool kernel = false;
        uintptr_t pc = get_interrupted_pc(&kernel);
        kperf_kpc_flags_t flags = kernel ? KPC_KERNEL_PC : 0;
        if ((config) & IA32_PERFEVT_USER_EN) {
                flags |= KPC_USER_COUNTING;
        }
        if ((config) & IA32_PERFEVT_OS_EN) {
                flags |= KPC_KERNEL_COUNTING;
        }
        kpc_sample_kperf(actionid, ctr,
            config & 0xffff /* just the number and umask */, count, pc, flags);
}

void
kpc_pmi_handler(void)
{
        uint64_t status, extra;
        uint32_t ctr;
        int enabled;

        enabled = ml_set_interrupts_enabled(FALSE);

        status = rdmsr64(MSR_IA32_PERF_GLOBAL_STATUS);

#ifdef FIXED_COUNTER_SHADOW
        for (ctr = 0; ctr < kpc_fixed_count(); ctr++) {
                if ((1ULL << (ctr + 32)) & status) {
                        extra = kpc_reload_fixed(ctr);

                        FIXED_SHADOW(ctr)
                                += (kpc_fixed_max() - FIXED_RELOAD(ctr) + 1 /* Wrap */) + extra;

                        BUF_INFO(PERF_KPC_FCOUNTER, ctr, FIXED_SHADOW(ctr), extra, FIXED_ACTIONID(ctr));

                        if (FIXED_ACTIONID(ctr)) {
                                kpc_sample_kperf_x86(ctr, FIXED_SHADOW(ctr) + extra, 0);
                        }
                }
        }
#endif

        for (ctr = 0; ctr < kpc_configurable_count(); ctr++) {
                if ((1ULL << ctr) & status) {
                        extra = kpc_reload_configurable(ctr);

                        CONFIGURABLE_SHADOW(ctr) += kpc_configurable_max() -
                            CONFIGURABLE_RELOAD(ctr) + extra;

                        /* kperf can grab the PMCs when it samples so we need to make sure the overflow
                         * bits are in the correct state before the call to kperf_sample */
                        wrmsr64(MSR_IA32_PERF_GLOBAL_OVF_CTRL, 1ull << ctr);

                        BUF_INFO(PERF_KPC_COUNTER, ctr, CONFIGURABLE_SHADOW(ctr), extra, CONFIGURABLE_ACTIONID(ctr));

                        if (CONFIGURABLE_ACTIONID(ctr)) {
                                uint64_t config = IA32_PERFEVTSELx(ctr);
                                kpc_sample_kperf_x86(ctr + kpc_configurable_count(),
                                    CONFIGURABLE_SHADOW(ctr) + extra, config);
                        }
                }
        }

        ml_set_interrupts_enabled(enabled);
}

int
kpc_set_sw_inc( uint32_t mask __unused )
{
        return ENOTSUP;
}

int
kpc_get_pmu_version(void)
{
        i386_cpu_info_t *info = cpuid_info();

        uint8_t version_id = info->cpuid_arch_perf_leaf.version;

        if (version_id == 3) {
                return KPC_PMU_INTEL_V3;
        } else if (version_id == 2) {
                return KPC_PMU_INTEL_V2;
        }

        return KPC_PMU_ERROR;
}