/* $NetBSD: kern_cpu.c,v 1.34 2008/07/14 01:27:15 rmind 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 __KERNEL_RCSID(0, "$NetBSD: kern_cpu.c,v 1.34 2008/07/14 01:27:15 rmind Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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 ((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 ((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(cpuid_t id) { CPU_INFO_ITERATOR cii; struct cpu_info *ci; for (CPU_INFO_FOREACH(cii, ci)) { if (ci->ci_cpuid == id) return ci; } return NULL; } struct cpu_info * cpu_lookup_byindex(u_int idx) { struct cpu_info *ci = cpu_infos[idx]; KASSERT(idx < MAXCPUS); 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); spc_dlock(ci, mci); LIST_FOREACH(l, &alllwp, l_list) { /* * Since runqueues are locked - LWPs cannot be enqueued (and * cannot change the state), thus is safe to perform the * checks without locking each LWP. */ if (l->l_cpu != ci || (l->l_pflag & LP_BOUND) != 0 || l->l_stat != LSRUN) continue; /* At this point, we are sure about the state of LWP */ KASSERT(lwp_locked(l, spc->spc_mutex)); if ((l->l_flag & LW_INMEM) != 0) { sched_dequeue(l); l->l_cpu = mci; lwp_setlock(l, mspc->spc_mutex); sched_enqueue(l, false); } else { l->l_cpu = mci; lwp_setlock(l, mspc->spc_mutex); } } spc_dunlock(ci, mci); 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; }