NetBSD/sys/kern/kern_cpu.c

342 lines
8.3 KiB
C

/* $NetBSD: kern_cpu.c,v 1.36 2008/10/15 08:13:17 ad Exp $ */
/*-
* Copyright (c) 2007, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Andrew Doran.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*-
* Copyright (c)2007 YAMAMOTO Takashi,
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_cpu.c,v 1.36 2008/10/15 08:13:17 ad Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/idle.h>
#include <sys/sched.h>
#include <sys/intr.h>
#include <sys/conf.h>
#include <sys/cpu.h>
#include <sys/cpuio.h>
#include <sys/proc.h>
#include <sys/percpu.h>
#include <sys/kernel.h>
#include <sys/kauth.h>
#include <sys/xcall.h>
#include <sys/pool.h>
#include <sys/kmem.h>
#include <sys/select.h>
#include <sys/namei.h>
#include <sys/callout.h>
#include <uvm/uvm_extern.h>
void cpuctlattach(int);
static void cpu_xc_online(struct cpu_info *);
static void cpu_xc_offline(struct cpu_info *);
dev_type_ioctl(cpuctl_ioctl);
const struct cdevsw cpuctl_cdevsw = {
nullopen, nullclose, nullread, nullwrite, cpuctl_ioctl,
nullstop, notty, nopoll, nommap, nokqfilter,
D_OTHER | D_MPSAFE
};
kmutex_t cpu_lock;
int ncpu;
int ncpuonline;
bool mp_online;
struct cpuqueue cpu_queue = CIRCLEQ_HEAD_INITIALIZER(cpu_queue);
static struct cpu_info *cpu_infos[MAXCPUS];
int
mi_cpu_attach(struct cpu_info *ci)
{
int error;
ci->ci_index = ncpu;
cpu_infos[cpu_index(ci)] = ci;
CIRCLEQ_INSERT_TAIL(&cpu_queue, ci, ci_data.cpu_qchain);
TAILQ_INIT(&ci->ci_data.cpu_ld_locks);
__cpu_simple_lock_init(&ci->ci_data.cpu_ld_lock);
sched_cpuattach(ci);
error = create_idle_lwp(ci);
if (error != 0) {
/* XXX revert sched_cpuattach */
return error;
}
if (ci == curcpu())
ci->ci_data.cpu_onproc = curlwp;
else
ci->ci_data.cpu_onproc = ci->ci_data.cpu_idlelwp;
percpu_init_cpu(ci);
softint_init(ci);
callout_init_cpu(ci);
xc_init_cpu(ci);
pool_cache_cpu_init(ci);
selsysinit(ci);
cache_cpu_init(ci);
TAILQ_INIT(&ci->ci_data.cpu_biodone);
ncpu++;
ncpuonline++;
return 0;
}
void
cpuctlattach(int dummy)
{
}
int
cpuctl_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l)
{
CPU_INFO_ITERATOR cii;
cpustate_t *cs;
struct cpu_info *ci;
int error, i;
u_int id;
error = 0;
mutex_enter(&cpu_lock);
switch (cmd) {
case IOC_CPU_SETSTATE:
cs = data;
error = kauth_authorize_system(l->l_cred,
KAUTH_SYSTEM_CPU, KAUTH_REQ_SYSTEM_CPU_SETSTATE, cs, NULL,
NULL);
if (error != 0)
break;
if (cs->cs_id >= __arraycount(cpu_infos) ||
(ci = cpu_lookup(cs->cs_id)) == NULL) {
error = ESRCH;
break;
}
if (!cs->cs_intr) {
error = EOPNOTSUPP;
break;
}
error = cpu_setonline(ci, cs->cs_online);
break;
case IOC_CPU_GETSTATE:
cs = data;
id = cs->cs_id;
memset(cs, 0, sizeof(*cs));
cs->cs_id = id;
if (cs->cs_id >= __arraycount(cpu_infos) ||
(ci = cpu_lookup(id)) == NULL) {
error = ESRCH;
break;
}
if ((ci->ci_schedstate.spc_flags & SPCF_OFFLINE) != 0)
cs->cs_online = false;
else
cs->cs_online = true;
cs->cs_intr = true;
cs->cs_lastmod = ci->ci_schedstate.spc_lastmod;
break;
case IOC_CPU_MAPID:
i = 0;
for (CPU_INFO_FOREACH(cii, ci)) {
if (i++ == *(int *)data)
break;
}
if (ci == NULL)
error = ESRCH;
else
*(int *)data = ci->ci_cpuid;
break;
case IOC_CPU_GETCOUNT:
*(int *)data = ncpu;
break;
default:
error = ENOTTY;
break;
}
mutex_exit(&cpu_lock);
return error;
}
struct cpu_info *
cpu_lookup(u_int idx)
{
struct cpu_info *ci = cpu_infos[idx];
KASSERT(idx < __arraycount(cpu_infos));
KASSERT(ci == NULL || cpu_index(ci) == idx);
return ci;
}
static void
cpu_xc_offline(struct cpu_info *ci)
{
struct schedstate_percpu *spc, *mspc = NULL;
struct cpu_info *mci;
struct lwp *l;
CPU_INFO_ITERATOR cii;
int s;
spc = &ci->ci_schedstate;
s = splsched();
spc->spc_flags |= SPCF_OFFLINE;
splx(s);
/* Take the first available CPU for the migration */
for (CPU_INFO_FOREACH(cii, mci)) {
mspc = &mci->ci_schedstate;
if ((mspc->spc_flags & SPCF_OFFLINE) == 0)
break;
}
KASSERT(mci != NULL);
/*
* Migrate all non-bound threads to the other CPU.
*
* Please note, that this runs from the xcall thread, thus handling
* of LSONPROC is not needed. Threads which change the state will
* be handled by sched_takecpu().
*/
mutex_enter(proc_lock);
LIST_FOREACH(l, &alllwp, l_list) {
lwp_lock(l);
if ((l->l_pflag & LP_BOUND) == 0 && l->l_cpu == ci) {
lwp_migrate(l, mci);
} else {
lwp_unlock(l);
}
}
mutex_exit(proc_lock);
#ifdef __HAVE_MD_CPU_OFFLINE
cpu_offline_md();
#endif
}
static void
cpu_xc_online(struct cpu_info *ci)
{
struct schedstate_percpu *spc;
int s;
spc = &ci->ci_schedstate;
s = splsched();
spc->spc_flags &= ~SPCF_OFFLINE;
splx(s);
}
int
cpu_setonline(struct cpu_info *ci, bool online)
{
struct schedstate_percpu *spc;
CPU_INFO_ITERATOR cii;
struct cpu_info *ci2;
uint64_t where;
xcfunc_t func;
int nonline;
spc = &ci->ci_schedstate;
KASSERT(mutex_owned(&cpu_lock));
if (online) {
if ((spc->spc_flags & SPCF_OFFLINE) == 0)
return 0;
func = (xcfunc_t)cpu_xc_online;
ncpuonline++;
} else {
if ((spc->spc_flags & SPCF_OFFLINE) != 0)
return 0;
nonline = 0;
/*
* Ensure that at least one CPU within the processor set
* stays online. Revisit this later.
*/
for (CPU_INFO_FOREACH(cii, ci2)) {
if ((ci2->ci_schedstate.spc_flags & SPCF_OFFLINE) != 0)
continue;
if (ci2->ci_schedstate.spc_psid != spc->spc_psid)
continue;
nonline++;
}
if (nonline == 1)
return EBUSY;
func = (xcfunc_t)cpu_xc_offline;
ncpuonline--;
}
where = xc_unicast(0, func, ci, NULL, ci);
xc_wait(where);
if (online) {
KASSERT((spc->spc_flags & SPCF_OFFLINE) == 0);
} else {
KASSERT(spc->spc_flags & SPCF_OFFLINE);
}
spc->spc_lastmod = time_second;
return 0;
}