sun4/os/mp_states.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include <sys/systm.h>
#include <sys/membar.h>
#include <sys/machsystm.h>
#include <sys/x_call.h>
#include <sys/platform_module.h>
#include <sys/cpuvar.h>
#include <sys/cpu_module.h>
#include <sys/cmp.h>
#include <sys/dumphdr.h>

#include <sys/cpu_sgnblk_defs.h>

static cpuset_t cpu_idle_set;
static kmutex_t cpu_idle_lock;
typedef const char *fn_t;

/*
 * flags to determine if the PROM routines
 * should be used to idle/resume/stop cpus
 */
static int kern_idle[NCPU];     /* kernel's idle loop */
static int cpu_are_paused;
extern void debug_flush_windows();

/*
 * Initialize the idlestop mutex
 */
void
idlestop_init(void)
{
    mutex_init(&cpu_idle_lock, NULL, MUTEX_SPIN, (void *)ipltospl(PIL_15));
}

static void
cpu_idle_self(void)
{
    uint_t s;
    label_t save;

    s = spl8();
    debug_flush_windows();

    CPU->cpu_m.in_prom = 1;
    membar_stld();

    save = curthread->t_pcb;
    (void) setjmp(&curthread->t_pcb);

    kern_idle[CPU->cpu_id] = 1;
    while (kern_idle[CPU->cpu_id])
        dumpsys_helper_nw();

    CPU->cpu_m.in_prom = 0;
    membar_stld();

    curthread->t_pcb = save;
    splx(s);
}

void
idle_other_cpus(void)
{
    int i, cpuid, ntries;
    int failed = 0;

    if (ncpus == 1)
        return;

    mutex_enter(&cpu_idle_lock);

    cpuid = CPU->cpu_id;
    ASSERT(cpuid < NCPU);

    cpu_idle_set = cpu_ready_set;
    CPUSET_DEL(cpu_idle_set, cpuid);

    if (CPUSET_ISNULL(cpu_idle_set))
        return;

    xt_some(cpu_idle_set, (xcfunc_t *)idle_stop_xcall,
        (uint64_t)cpu_idle_self, NULL);

    for (i = 0; i < NCPU; i++) {
        if (!CPU_IN_SET(cpu_idle_set, i))
            continue;

        ntries = 0x10000;
        while (!cpu[i]->cpu_m.in_prom && ntries) {
            DELAY(50);
            ntries--;
        }

        /*
         * A cpu failing to idle is an error condition, since
         * we can't be sure anymore of its state.
         */
        if (!cpu[i]->cpu_m.in_prom) {
            cmn_err(CE_WARN, "cpuid 0x%x failed to idle", i);
            failed++;
        }
    }

    if (failed) {
        mutex_exit(&cpu_idle_lock);
        cmn_err(CE_PANIC, "idle_other_cpus: not all cpus idled");
    }
}

void
resume_other_cpus(void)
{
    int i, ntries;
    int cpuid = CPU->cpu_id;
    boolean_t failed = B_FALSE;

    if (ncpus == 1)
        return;

    ASSERT(cpuid < NCPU);
    ASSERT(MUTEX_HELD(&cpu_idle_lock));

    for (i = 0; i < NCPU; i++) {
        if (!CPU_IN_SET(cpu_idle_set, i))
            continue;

        kern_idle[i] = 0;
        membar_stld();
    }

    for (i = 0; i < NCPU; i++) {
        if (!CPU_IN_SET(cpu_idle_set, i))
            continue;

        ntries = 0x10000;
        while (cpu[i]->cpu_m.in_prom && ntries) {
            DELAY(50);
            ntries--;
        }

        /*
         * A cpu failing to resume is an error condition, since
         * intrs may have been directed there.
         */
        if (cpu[i]->cpu_m.in_prom) {
            cmn_err(CE_WARN, "cpuid 0x%x failed to resume", i);
            continue;
        }
        CPUSET_DEL(cpu_idle_set, i);
    }

    failed = !CPUSET_ISNULL(cpu_idle_set);

    mutex_exit(&cpu_idle_lock);

    /*
     * Non-zero if a cpu failed to resume
     */
    if (failed)
        cmn_err(CE_PANIC, "resume_other_cpus: not all cpus resumed");

}

/*
 * Stop all other cpu's before halting or rebooting. We pause the cpu's
 * instead of sending a cross call.
 */
void
stop_other_cpus(void)
{
    mutex_enter(&cpu_lock);
    if (cpu_are_paused) {
        mutex_exit(&cpu_lock);
        return;
    }

    if (ncpus > 1)
        intr_redist_all_cpus_shutdown();

    pause_cpus(NULL, NULL);
    cpu_are_paused = 1;

    mutex_exit(&cpu_lock);
}

int cpu_quiesce_microsecond_sanity_limit = 60 * 1000000;

void
mp_cpu_quiesce(cpu_t *cp0)
{

    volatile cpu_t  *cp = (volatile cpu_t *) cp0;
    int i, sanity_limit = cpu_quiesce_microsecond_sanity_limit;
    int     cpuid = cp->cpu_id;
    int         found_intr = 1;
    static fn_t f = "mp_cpu_quiesce";

    ASSERT(CPU->cpu_id != cpuid);
    ASSERT(MUTEX_HELD(&cpu_lock));
    ASSERT(cp->cpu_flags & CPU_QUIESCED);


    /*
     * Declare CPU as no longer being READY to process interrupts and
     * wait for them to stop. A CPU that is not READY can no longer
     * participate in x-calls or x-traps.
     */
    cp->cpu_flags &= ~CPU_READY;
    CPUSET_DEL(cpu_ready_set, cpuid);
    membar_sync();

    for (i = 0; i < sanity_limit; i++) {
        if (cp->cpu_intr_actv == 0 &&
            (cp->cpu_thread == cp->cpu_idle_thread ||
            cp->cpu_thread == cp->cpu_startup_thread)) {
            found_intr = 0;
            break;
        }
        DELAY(1);
    }

    if (found_intr) {

        if (cp->cpu_intr_actv) {
            cmn_err(CE_PANIC, "%s: cpu_intr_actv != 0", f);
        } else if (cp->cpu_thread != cp->cpu_idle_thread &&
            cp->cpu_thread != cp->cpu_startup_thread) {
            cmn_err(CE_PANIC, "%s: CPU %d is not quiesced",
                f, cpuid);
        }

    }
}

/*
 * Start CPU on user request.
 */
/* ARGSUSED */
int
mp_cpu_start(struct cpu *cp)
{
    ASSERT(MUTEX_HELD(&cpu_lock));
    /*
     * Platforms that use CPU signatures require the signature
     * block update to indicate that this CPU is in the OS now.
     */
    CPU_SIGNATURE(OS_SIG, SIGST_RUN, SIGSUBST_NULL, cp->cpu_id);

    cmp_error_resteer(cp->cpu_id);

    return (0);         /* nothing special to do on this arch */
}

/*
 * Stop CPU on user request.
 */
/* ARGSUSED */
int
mp_cpu_stop(struct cpu *cp)
{
    ASSERT(MUTEX_HELD(&cpu_lock));

    cmp_error_resteer(cp->cpu_id);

    /*
     * Platforms that use CPU signatures require the signature
     * block update to indicate that this CPU is offlined now.
     */
    CPU_SIGNATURE(OS_SIG, SIGST_OFFLINE, SIGSUBST_NULL, cp->cpu_id);
    return (0);         /* nothing special to do on this arch */
}

/*
 * Power on CPU.
 */
int
mp_cpu_poweron(struct cpu *cp)
{
    ASSERT(MUTEX_HELD(&cpu_lock));
    if (&plat_cpu_poweron)
        return (plat_cpu_poweron(cp));  /* platform-dependent hook */

    return (ENOTSUP);
}

/*
 * Power off CPU.
 */
int
mp_cpu_poweroff(struct cpu *cp)
{
    ASSERT(MUTEX_HELD(&cpu_lock));
    if (&plat_cpu_poweroff)
        return (plat_cpu_poweroff(cp)); /* platform-dependent hook */

    return (ENOTSUP);
}

void
mp_cpu_faulted_enter(struct cpu *cp)
{
    cpu_faulted_enter(cp);
}

void
mp_cpu_faulted_exit(struct cpu *cp)
{
    cpu_faulted_exit(cp);
}