/* $NetBSD: kern_sa.c,v 1.46 2003/11/28 08:18:03 scw Exp $ */ /*- * Copyright (c) 2001 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Nathan J. Williams. * * 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the NetBSD * Foundation, Inc. and its contributors. * 4. Neither the name of The NetBSD Foundation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * 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. */ #include __KERNEL_RCSID(0, "$NetBSD: kern_sa.c,v 1.46 2003/11/28 08:18:03 scw Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include static __inline int sast_compare(struct sastack *, struct sastack *); static void sa_setwoken(struct lwp *); static int sa_newcachelwp(struct lwp *); static struct lwp *sa_vp_repossess(struct lwp *l); static __inline int sa_pagefault(struct lwp *, ucontext_t *); void sa_upcall_getstate(union sau_state *, struct lwp *); MALLOC_DEFINE(M_SA, "sa", "Scheduler activations"); #define SA_DEBUG #ifdef SA_DEBUG #define DPRINTF(x) do { if (sadebug) printf x; } while (0) #define DPRINTFN(n,x) do { if (sadebug & (1<<(n-1))) printf x; } while (0) int sadebug = 0; #else #define DPRINTF(x) #define DPRINTFN(n,x) #endif #define SA_LWP_STATE_LOCK(l, f) do { \ (f) = (l)->l_flag; \ (l)->l_flag &= ~L_SA; \ } while (/*CONSTCOND*/ 0) #define SA_LWP_STATE_UNLOCK(l, f) do { \ (l)->l_flag |= (f) & L_SA; \ } while (/*CONSTCOND*/ 0) SPLAY_PROTOTYPE(sasttree, sastack, sast_node, sast_compare); SPLAY_GENERATE(sasttree, sastack, sast_node, sast_compare); /* * sadata_upcall_alloc: * * Allocate an sadata_upcall structure. */ struct sadata_upcall * sadata_upcall_alloc(int waitok) { /* XXX zero the memory? */ return (pool_get(&saupcall_pool, waitok ? PR_WAITOK : PR_NOWAIT)); } /* * sadata_upcall_free: * * Free an sadata_upcall structure, and any associated * argument data. */ void sadata_upcall_free(struct sadata_upcall *sau) { extern struct pool siginfo_pool; /* XXX Ew. */ /* * XXX We have to know what the origin of sau_arg is * XXX in order to do the right thing, here. Sucks * XXX to be a non-garbage-collecting kernel. */ if (sau->sau_arg) { switch (sau->sau_type) { case SA_UPCALL_SIGNAL: case SA_UPCALL_SIGEV: pool_put(&siginfo_pool, sau->sau_arg); break; default: panic("sadata_free: unknown type of sau_arg: %d", sau->sau_type); } } pool_put(&saupcall_pool, sau); } int sys_sa_register(struct lwp *l, void *v, register_t *retval) { struct sys_sa_register_args /* { syscallarg(sa_upcall_t) new; syscallarg(sa_upcall_t *) old; syscallarg(int) flags; } */ *uap = v; struct proc *p = l->l_proc; struct sadata *sa; sa_upcall_t prev; int error; if (p->p_sa == NULL) { /* Allocate scheduler activations data structure */ sa = pool_get(&sadata_pool, PR_WAITOK); /* Initialize. */ memset(sa, 0, sizeof(*sa)); simple_lock_init(&sa->sa_lock); sa->sa_flag = SCARG(uap, flags) & SA_FLAG_ALL; sa->sa_vp = NULL; sa->sa_wokenq_head = NULL; sa->sa_concurrency = 1; SPLAY_INIT(&sa->sa_stackstree); SLIST_INIT(&sa->sa_stackslist); sa->sa_nstacks = 0; sa->sa_vp_faultaddr = 0; sa->sa_vp_ofaultaddr = 0; LIST_INIT(&sa->sa_lwpcache); SIMPLEQ_INIT(&sa->sa_upcalls); p->p_sa = sa; sa_newcachelwp(l); } prev = p->p_sa->sa_upcall; p->p_sa->sa_upcall = SCARG(uap, new); if (SCARG(uap, old)) { error = copyout(&prev, SCARG(uap, old), sizeof(prev)); if (error) return (error); } return (0); } void sa_release(struct proc *p) { struct sadata *sa; struct sastack *sast, *next; sa = p->p_sa; KDASSERT(sa != NULL); for (sast = SPLAY_MIN(sasttree, &sa->sa_stackstree); sast != NULL; sast = next) { next = SPLAY_NEXT(sasttree, &sa->sa_stackstree, sast); SPLAY_REMOVE(sasttree, &sa->sa_stackstree, sast); pool_put(&sastack_pool, sast); } p->p_flag &= ~P_SA; pool_put(&sadata_pool, sa); p->p_sa = NULL; } static __inline int sast_compare(struct sastack *a, struct sastack *b) { if ((vaddr_t)a->sast_stack.ss_sp + a->sast_stack.ss_size <= (vaddr_t)b->sast_stack.ss_sp) return (-1); if ((vaddr_t)a->sast_stack.ss_sp >= (vaddr_t)b->sast_stack.ss_sp + b->sast_stack.ss_size) return (1); return (0); } int sys_sa_stacks(struct lwp *l, void *v, register_t *retval) { struct sys_sa_stacks_args /* { syscallarg(int) num; syscallarg(stack_t *) stacks; } */ *uap = v; struct sadata *sa = l->l_proc->p_sa; struct lwp *l2; struct sastack *sast, newsast; int count, error, f, i; /* We have to be using scheduler activations */ if (sa == NULL) return (EINVAL); count = SCARG(uap, num); if (count < 0) return (EINVAL); SA_LWP_STATE_LOCK(l, f); error = 0; for (i = 0; i < count; i++) { error = copyin(SCARG(uap, stacks) + i, &newsast.sast_stack, sizeof(stack_t)); if (error) { count = i; break; } if ((sast = SPLAY_FIND(sasttree, &sa->sa_stackstree, &newsast))) { DPRINTFN(9, ("sa_stacks(%d.%d) returning stack %p\n", l->l_proc->p_pid, l->l_lid, newsast.sast_stack.ss_sp)); if ((l2 = sast->sast_blocker)) { l2->l_upcallstack = NULL; sast->sast_blocker = NULL; } if (SLIST_NEXT(sast, sast_list) != (void *)-1) { count = i; error = EEXIST; break; } } else if (sa->sa_nstacks >= SA_MAXNUMSTACKS * sa->sa_concurrency) { DPRINTFN(9, ("sa_stacks(%d.%d) already using %d stacks\n", l->l_proc->p_pid, l->l_lid, SA_MAXNUMSTACKS * sa->sa_concurrency)); count = i; error = ENOMEM; break; } else { DPRINTFN(9, ("sa_stacks(%d.%d) adding stack %p\n", l->l_proc->p_pid, l->l_lid, newsast.sast_stack.ss_sp)); sast = pool_get(&sastack_pool, PR_WAITOK); sast->sast_stack = newsast.sast_stack; sast->sast_blocker = NULL; SPLAY_INSERT(sasttree, &sa->sa_stackstree, sast); sa->sa_nstacks++; } SLIST_INSERT_HEAD(&sa->sa_stackslist, sast, sast_list); } /* * Check if there are any pending upcalls we didn't make * because there were not enough stacks. */ if (sa->sa_wokenq_head != NULL) l->l_flag |= L_SA_UPCALL; SA_LWP_STATE_UNLOCK(l, f); *retval = count; return (error); } int sys_sa_enable(struct lwp *l, void *v, register_t *retval) { struct proc *p = l->l_proc; struct sadata *sa = p->p_sa; int error; DPRINTF(("sys_sa_enable(%d.%d)\n", l->l_proc->p_pid, l->l_lid)); /* We have to be using scheduler activations */ if (sa == NULL) return (EINVAL); if (p->p_flag & P_SA) /* Already running! */ return (EBUSY); error = sa_upcall(l, SA_UPCALL_NEWPROC, l, NULL, 0, NULL); if (error) return (error); /* Assign this LWP to the virtual processor */ sa->sa_vp = l; p->p_flag |= P_SA; l->l_flag |= L_SA; /* We are now an activation LWP */ /* This will not return to the place in user space it came from. */ return (0); } int sys_sa_setconcurrency(struct lwp *l, void *v, register_t *retval) { struct sys_sa_setconcurrency_args /* { syscallarg(int) concurrency; } */ *uap = v; struct sadata *sa = l->l_proc->p_sa; DPRINTF(("sys_sa_concurrency(%d.%d)\n", l->l_proc->p_pid, l->l_lid)); /* We have to be using scheduler activations */ if (sa == NULL) return (EINVAL); if (SCARG(uap, concurrency) < 1) return (EINVAL); *retval = sa->sa_concurrency; /* * Concurrency greater than the number of physical CPUs does * not make sense. * XXX Should we ever support hot-plug CPUs, this will need * adjustment. */ sa->sa_concurrency = min(SCARG(uap, concurrency), 1 /* XXX ncpus */); return (0); } int sys_sa_yield(struct lwp *l, void *v, register_t *retval) { struct proc *p = l->l_proc; if (p->p_sa == NULL || !(p->p_flag & P_SA)) { DPRINTFN(1,("sys_sa_yield(%d.%d) proc %p not SA (p_sa %p, flag %s)\n", p->p_pid, l->l_lid, p, p->p_sa, p->p_flag & P_SA ? "T" : "F")); return (EINVAL); } sa_yield(l); return (0); } void sa_yield(struct lwp *l) { struct proc *p = l->l_proc; #ifdef DEBUG struct sadata *sa = p->p_sa; #endif int ret, s; #if defined(MULTIPROCESSOR) KDASSERT(l->l_flag & L_BIGLOCK); #endif /* * If we're the last running LWP, stick around to recieve * signals. */ KDASSERT((l->l_flag & L_SA_YIELD) == 0); DPRINTFN(1,("sa_yield(%d.%d) going dormant\n", p->p_pid, l->l_lid)); /* * A signal will probably wake us up. Worst case, the upcall * happens and just causes the process to yield again. */ s = splsched(); /* Protect from timer expirations */ KDASSERT(sa->sa_vp == l); /* * If we were told to make an upcall or exit before * the splsched(), make sure we process it instead of * going to sleep. It might make more sense for this to * be handled inside of tsleep.... */ ret = 0; while (ret == 0 && p->p_userret == NULL && (l->l_flag & L_SA_UPCALL) == 0) { l->l_flag |= L_SA_YIELD; ret = tsleep((caddr_t) l, PUSER | PCATCH, "sawait", 0); l->l_flag &= ~L_SA_YIELD; if (p->p_flag & P_WEXIT) lwp_exit(l); KDASSERT(sa->sa_vp == l); } splx(s); DPRINTFN(1,("sa_yield(%d.%d) returned\n", p->p_pid, l->l_lid)); } int sys_sa_preempt(struct lwp *l, void *v, register_t *retval) { /* XXX Implement me. */ return (ENOSYS); } /* XXX Hm, naming collision. */ void sa_preempt(struct lwp *l) { struct proc *p = l->l_proc; struct sadata *sa = p->p_sa; /* * Defer saving the lwp's state because on some ports * preemption can occur between generating an unblocked upcall * and processing the upcall queue. */ if (sa->sa_flag & SA_FLAG_PREEMPT) sa_upcall(l, SA_UPCALL_PREEMPTED | SA_UPCALL_DEFER_EVENT, l, NULL, 0, NULL); } /* * Help userspace library resolve locks and critical sections: * - return if the unblocked upcall has already been delivered. * This case is usually already detected in userspace. * - recycles the calling LWP and its stack if it was not preempted * and the unblocked upcall was not yet delivered. Put the sa_id * LWP on the VP and wait until it unblocks or switch to it if it's * ready. There will be no unblocked upcall. * - recycles the blocked LWP if up_preempted == NULL. This is used * if the blocked LWP is an idle thread and we don't care for the * unblocked upcall. * - otherwise, wait for the blocked LWP to get ready. The unblocked * upcall is delivered when we return. * This is used if a thread blocks (mostly because of a pagefault) and * is in a critical section in the userspace library and the critical * section resolving code cannot continue until the blocked thread is * unblocked. */ int sys_sa_unblockyield(struct lwp *l, void *v, register_t *retval) { struct sys_sa_unblockyield_args /* { syscallarg(int) sa_id; syscallarg(void *) up_preempted; syscallarg(stack_t *) up_stack; } */ *uap = v; struct sadata *sa = l->l_proc->p_sa; struct proc *p = l->l_proc; struct lwp *l2, **hp; struct sastack sast; int error, f, s; void *preempted; if (sa == NULL) return (EINVAL); SA_LWP_STATE_LOCK(l, f); error = copyin(SCARG(uap, up_stack), &sast.sast_stack, sizeof(stack_t)); if (error) { SA_LWP_STATE_UNLOCK(l, f); return (error); } if (SCARG(uap, up_preempted) != NULL) { error = copyin(SCARG(uap, up_preempted), &preempted, sizeof(void *)); if (error) { SA_LWP_STATE_UNLOCK(l, f); return (error); } } else preempted = (void *)-1; SA_LWP_STATE_UNLOCK(l, f); SCHED_LOCK(s); LIST_FOREACH(l2, &p->p_lwps, l_sibling) { if (l2->l_lid == SCARG(uap, sa_id)) { break; } } if (l2 && (l2->l_upcallstack == NULL || (l2->l_upcallstack->sast_blocker != l2 && l2->l_upcallstack->sast_blocker != NULL))) l2 = NULL; if (l2 == NULL) { /* just return, prevented in userland most of the time */ DPRINTFN(11,("sys_sa_unblockyield(%d.%d) unblocked upcall done\n", p->p_pid, l->l_lid)); KDASSERT(preempted != NULL); } else if (preempted == (void *)-1) { /* recycle blocked LWP */ DPRINTFN(11,("sys_sa_unblockyield(%d.%d) recycle %d " "(was %sready) upcall stack %p\n", p->p_pid, l->l_lid, l2->l_lid, (l2->l_upcallstack->sast_blocker == NULL) ? "" : "not ", l2->l_upcallstack->sast_stack.ss_sp)); if (l2->l_upcallstack->sast_blocker == NULL) { /* * l2 is on the wokenq, remove it and put l2 * in the cache */ hp = &sa->sa_wokenq_head; while (*hp != l2) hp = &(*hp)->l_forw; *hp = l2->l_forw; if (sa->sa_wokenq_tailp == &l2->l_forw) sa->sa_wokenq_tailp = hp; l2->l_flag &= ~L_SA_BLOCKING; l2->l_upcallstack = NULL; sa_putcachelwp(p, l2); /* PHOLD from sa_setwoken */ } else /* let sa_setwoken put it in the cache */ l2->l_upcallstack->sast_blocker = NULL; } else if (preempted != NULL) { /* wait for the blocked LWP to get ready, then return */ DPRINTFN(11,("sys_sa_unblockyield(%d.%d) waiting for %d " "(was %sready) upcall stack %p\n", p->p_pid, l->l_lid, l2->l_lid, (l2->l_upcallstack->sast_blocker == NULL) ? "" : "not ", l2->l_upcallstack->sast_stack.ss_sp)); if (l2->l_upcallstack->sast_blocker != NULL) { l2->l_upcallstack->sast_blocker = l; SCHED_UNLOCK(s); /* XXXcl we're still holding * the kernel lock, is that * good enough? */ SA_LWP_STATE_LOCK(l, f); tsleep((caddr_t) &l2->l_upcallstack, PWAIT, "saunblock", 0); SA_LWP_STATE_UNLOCK(l, f); if (p->p_flag & P_WEXIT) lwp_exit(l); return(0); } } else { /* recycle calling LWP and resume blocked LWP */ DPRINTFN(11,("sys_sa_unblockyield(%d.%d) resuming %d " "(is %sready) upcall stack %p\n", p->p_pid, l->l_lid, l2->l_lid, (l2->l_upcallstack->sast_blocker == NULL) ? "" : "not ", l2->l_upcallstack->sast_stack.ss_sp)); sa->sa_vp = l2; l2->l_flag &= ~L_SA_BLOCKING; SLIST_INSERT_HEAD(&sa->sa_stackslist, l2->l_upcallstack, sast_list); if (l2->l_upcallstack->sast_blocker == NULL) { /* * l2 is on the wokenq, remove it and * continue l2 */ hp = &sa->sa_wokenq_head; while (*hp != l2) hp = &(*hp)->l_forw; *hp = l2->l_forw; if (sa->sa_wokenq_tailp == &l2->l_forw) sa->sa_wokenq_tailp = hp; l2->l_upcallstack = NULL; setrunnable(l2); PRELE(l2); /* PHOLD from sa_setwoken */ } else { /* cleanup l_upcallstack */ l2->l_upcallstack->sast_blocker = NULL; l2->l_upcallstack = NULL; l2 = NULL; /* don't continue l2 yet */ } p->p_nrlwps--; PHOLD(l); sa_putcachelwp(p, l); mi_switch(l, l2); /* mostly NOTREACHED */ SCHED_ASSERT_UNLOCKED(); splx(s); KDASSERT(p->p_flag & P_WEXIT); lwp_exit(l); } SCHED_UNLOCK(s); return (0); } /* * Set up the user-level stack and trapframe to do an upcall. * * NOTE: This routine WILL FREE "arg" in the case of failure! Callers * should not touch the "arg" pointer once calling sa_upcall(). */ int sa_upcall(struct lwp *l, int type, struct lwp *event, struct lwp *interrupted, size_t argsize, void *arg) { struct sadata_upcall *sau; struct sadata *sa = l->l_proc->p_sa; struct sastack *sast; int error, f; /* XXX prevent recursive upcalls if we sleep formemory */ SA_LWP_STATE_LOCK(l, f); sau = sadata_upcall_alloc(1); SA_LWP_STATE_UNLOCK(l, f); sast = SLIST_FIRST(&sa->sa_stackslist); if (sast == NULL) { /* assign to assure that it gets freed */ sau->sau_type = type & SA_UPCALL_TYPE_MASK; sau->sau_arg = arg; sadata_upcall_free(sau); return (ENOMEM); } SLIST_REMOVE_HEAD(&sa->sa_stackslist, sast_list); SLIST_NEXT(sast, sast_list) = (void *)-1; DPRINTFN(9,("sa_upcall(%d.%d) using stack %p\n", l->l_proc->p_pid, l->l_lid, sast->sast_stack.ss_sp)); error = sa_upcall0(l, type, event, interrupted, argsize, arg, sau, &sast->sast_stack); if (error) { SLIST_INSERT_HEAD(&sa->sa_stackslist, sast, sast_list); sadata_upcall_free(sau); return (error); } SIMPLEQ_INSERT_TAIL(&sa->sa_upcalls, sau, sau_next); l->l_flag |= L_SA_UPCALL; return (0); } int sa_upcall0(struct lwp *l, int type, struct lwp *event, struct lwp *interrupted, size_t argsize, void *arg, struct sadata_upcall *sau, stack_t *st) { KDASSERT((event == NULL) || (event != interrupted)); sau->sau_flags = 0; sau->sau_type = type & SA_UPCALL_TYPE_MASK; sau->sau_argsize = argsize; sau->sau_arg = arg; sau->sau_stack = *st; if (type & SA_UPCALL_DEFER_EVENT) { sau->sau_event.ss_deferred.ss_lwp = event; sau->sau_flags |= SAU_FLAG_DEFERRED_EVENT; } else sa_upcall_getstate(&sau->sau_event, event); if (type & SA_UPCALL_DEFER_INTERRUPTED) { sau->sau_interrupted.ss_deferred.ss_lwp = interrupted; sau->sau_flags |= SAU_FLAG_DEFERRED_INTERRUPTED; } else sa_upcall_getstate(&sau->sau_interrupted, interrupted); return (0); } void sa_upcall_getstate(union sau_state *ss, struct lwp *l) { if (l) { getucontext(l, &ss->ss_captured.ss_ctx); ss->ss_captured.ss_sa.sa_context = (ucontext_t *) (intptr_t)((_UC_MACHINE_SP(&ss->ss_captured.ss_ctx) - sizeof(ucontext_t)) #ifdef _UC_UCONTEXT_ALIGN & _UC_UCONTEXT_ALIGN #endif ); ss->ss_captured.ss_sa.sa_id = l->l_lid; ss->ss_captured.ss_sa.sa_cpu = 0; /* XXX extract from l_cpu */ } else ss->ss_captured.ss_sa.sa_context = NULL; } /* * Detect double pagefaults and pagefaults on upcalls. * - double pagefaults are detected by comparing the previous faultaddr * against the current faultaddr * - pagefaults on upcalls are detected by checking if the userspace * thread is running on an upcall stack */ static __inline int sa_pagefault(struct lwp *l, ucontext_t *l_ctx) { struct proc *p; struct sadata *sa; struct sastack sast; p = l->l_proc; sa = p->p_sa; KDASSERT(sa->sa_vp == l); if (sa->sa_vp_faultaddr == sa->sa_vp_ofaultaddr) { DPRINTFN(10,("sa_pagefault(%d.%d) double page fault\n", p->p_pid, l->l_lid)); return 1; } sast.sast_stack.ss_sp = (void *)(intptr_t)_UC_MACHINE_SP(l_ctx); sast.sast_stack.ss_size = 1; if (SPLAY_FIND(sasttree, &sa->sa_stackstree, &sast)) { DPRINTFN(10,("sa_pagefault(%d.%d) upcall page fault\n", p->p_pid, l->l_lid)); return 1; } sa->sa_vp_ofaultaddr = sa->sa_vp_faultaddr; return 0; } /* * Called by tsleep(). Block current LWP and switch to another. * * WE ARE NOT ALLOWED TO SLEEP HERE! WE ARE CALLED FROM WITHIN * TSLEEP() ITSELF! We are called with sched_lock held, and must * hold it right through the mi_switch() call. */ void sa_switch(struct lwp *l, int type) { struct proc *p = l->l_proc; struct sadata *sa = p->p_sa; struct sadata_upcall *sau; struct lwp *l2; struct sastack *sast; int error, s; DPRINTFN(4,("sa_switch(%d.%d type %d VP %d)\n", p->p_pid, l->l_lid, type, sa->sa_vp ? sa->sa_vp->l_lid : 0)); SCHED_ASSERT_LOCKED(); if (p->p_flag & P_WEXIT) { mi_switch(l, NULL); return; } if (l->l_flag & L_SA_YIELD) { /* * Case 0: we're blocking in sa_yield */ if (sa->sa_wokenq_head == NULL) { l->l_flag |= L_SA_IDLE; mi_switch(l, NULL); } else { /* make us running again. */ unsleep(l); l->l_stat = LSONPROC; l->l_proc->p_nrlwps++; s = splsched(); SCHED_UNLOCK(s); } return; } else if (sa->sa_vp == l) { /* * Case 1: we're blocking for the first time; generate * a SA_BLOCKED upcall and allocate resources for the * UNBLOCKED upcall. */ /* * The process of allocating a new LWP could cause * sleeps. We're called from inside sleep, so that * would be Bad. Therefore, we must use a cached new * LWP. The first thing that this new LWP must do is * allocate another LWP for the cache. */ l2 = sa_getcachelwp(p); if (l2 == NULL) { /* XXXSMP */ /* No upcall for you! */ /* XXX The consequences of this are more subtle and * XXX the recovery from this situation deserves * XXX more thought. */ /* XXXUPSXXX Should only happen with concurrency > 1 */ #ifdef DIAGNOSTIC printf("sa_switch(%d.%d): no cached LWP for upcall.\n", p->p_pid, l->l_lid); #endif mi_switch(l, NULL); return; } sast = SLIST_FIRST(&sa->sa_stackslist); if (sast == NULL) { #ifdef DIAGNOSTIC printf("sa_switch(%d.%d flag %x): Not enough stacks.\n", p->p_pid, l->l_lid, l->l_flag); #endif sa_putcachelwp(p, l2); /* PHOLD from sa_getcachelwp */ mi_switch(l, NULL); return; } SLIST_REMOVE_HEAD(&sa->sa_stackslist, sast_list); SLIST_NEXT(sast, sast_list) = (void *)-1; DPRINTFN(9,("sa_switch(%d.%d) using stack %p\n", l->l_proc->p_pid, l->l_lid, sast->sast_stack.ss_sp)); /* * XXX We need to allocate the sadata_upcall structure here, * XXX since we can't sleep while waiting for memory inside * XXX sa_upcall(). It would be nice if we could safely * XXX allocate the sadata_upcall structure on the stack, here. */ sau = sadata_upcall_alloc(0); if (sau == NULL) { #ifdef DIAGNOSTIC printf("sa_switch(%d.%d): couldn't allocate upcall data.\n", p->p_pid, l->l_lid); #endif SLIST_INSERT_HEAD(&sa->sa_stackslist, sast, sast_list); sa_putcachelwp(p, l2); /* PHOLD from sa_getcachelwp */ mi_switch(l, NULL); return; } cpu_setfunc(l2, sa_switchcall, l2); error = sa_upcall0(l2, SA_UPCALL_BLOCKED, l, NULL, 0, NULL, sau, &sast->sast_stack); if (error) { #ifdef DIAGNOSTIC printf("sa_switch(%d.%d): Error %d from sa_upcall()\n", p->p_pid, l->l_lid, error); #endif SLIST_INSERT_HEAD(&sa->sa_stackslist, sast, sast_list); sa_putcachelwp(p, l2); /* PHOLD from sa_getcachelwp */ mi_switch(l, NULL); return; } /* * Perform the double/upcall pagefault check. * We do this only here since we need l's ucontext to * get l's userspace stack. sa_upcall0 above has saved * it for us. * The L_SA_PAGEFAULT flag is set in the MD * pagefault code to indicate a pagefault. The MD * pagefault code also saves the faultaddr for us. */ if ((l->l_flag & L_SA_PAGEFAULT) && sa_pagefault(l, &sau->sau_event.ss_captured.ss_ctx) != 0) { sadata_upcall_free(sau); SLIST_INSERT_HEAD(&sa->sa_stackslist, sast, sast_list); sa_putcachelwp(p, l2); /* PHOLD from sa_getcachelwp */ mi_switch(l, NULL); DPRINTFN(10,("sa_switch(%d.%d) page fault resolved\n", p->p_pid, l->l_lid)); return; } DPRINTFN(8,("sa_switch(%d.%d) blocked upcall %d, stack %p\n", p->p_pid, l->l_lid, l2->l_lid, sast->sast_stack.ss_sp)); SIMPLEQ_INSERT_TAIL(&sa->sa_upcalls, sau, sau_next); l2->l_flag |= L_SA_UPCALL; l->l_flag |= L_SA_BLOCKING; sast->sast_blocker = l; l->l_upcallstack = sast; l2->l_priority = l2->l_usrpri; sa->sa_vp = l2; setrunnable(l2); PRELE(l2); /* Remove the artificial hold-count */ KDASSERT(l2 != l); } else if (sa->sa_vp != NULL) { /* * Case 2: We've been woken up while another LWP was * on the VP, but we're going back to sleep without * having returned to userland and delivering the * SA_UNBLOCKED upcall (select and poll cause this * kind of behavior a lot). We just switch back to the * LWP that had been running and let it have another * go. If the LWP on the VP was idling, don't make it * run again, though. */ if (sa->sa_vp->l_flag & L_SA_YIELD) l2 = NULL; else { l2 = sa->sa_vp; /* XXXUPSXXX Unfair advantage for l2 ? */ if((l2->l_stat != LSRUN) || ((l2->l_flag & L_INMEM) == 0)) l2 = NULL; } } else { /* NOTREACHED */ panic("sa_vp empty"); } DPRINTFN(4,("sa_switch(%d.%d) switching to LWP %d.\n", p->p_pid, l->l_lid, l2 ? l2->l_lid : 0)); mi_switch(l, l2); DPRINTFN(4,("sa_switch(%d.%d flag %x) returned.\n", p->p_pid, l->l_lid, l->l_flag)); KDASSERT(l->l_wchan == 0); SCHED_ASSERT_UNLOCKED(); } void sa_switchcall(void *arg) { struct lwp *l; struct proc *p; struct sadata *sa; int f; l = arg; p = l->l_proc; sa = p->p_sa; sa->sa_vp = l; DPRINTFN(6,("sa_switchcall(%d.%d)\n", p->p_pid, l->l_lid)); if (LIST_EMPTY(&sa->sa_lwpcache)) { /* Allocate the next cache LWP */ DPRINTFN(6,("sa_switchcall(%d.%d) allocating LWP\n", p->p_pid, l->l_lid)); SA_LWP_STATE_LOCK(l, f); sa_newcachelwp(l); SA_LWP_STATE_UNLOCK(l, f); } upcallret(l); } static int sa_newcachelwp(struct lwp *l) { struct proc *p; struct lwp *l2; vaddr_t uaddr; boolean_t inmem; int s; p = l->l_proc; if (p->p_flag & P_WEXIT) return (0); inmem = uvm_uarea_alloc(&uaddr); if (__predict_false(uaddr == 0)) { return (ENOMEM); } else { newlwp(l, p, uaddr, inmem, 0, NULL, 0, child_return, 0, &l2); /* We don't want this LWP on the process's main LWP list, but * newlwp helpfully puts it there. Unclear if newlwp should * be tweaked. */ PHOLD(l2); SCHED_LOCK(s); sa_putcachelwp(p, l2); SCHED_UNLOCK(s); } return (0); } /* * Take a normal process LWP and place it in the SA cache. * LWP must not be running! */ void sa_putcachelwp(struct proc *p, struct lwp *l) { struct sadata *sa; SCHED_ASSERT_LOCKED(); sa = p->p_sa; LIST_REMOVE(l, l_sibling); p->p_nlwps--; l->l_stat = LSSUSPENDED; l->l_flag |= (L_DETACHED | L_SA); /* XXX lock sadata */ DPRINTFN(5,("sa_putcachelwp(%d.%d) Adding LWP %d to cache\n", p->p_pid, curlwp->l_lid, l->l_lid)); LIST_INSERT_HEAD(&sa->sa_lwpcache, l, l_sibling); sa->sa_ncached++; /* XXX unlock */ } /* * Fetch a LWP from the cache. */ struct lwp * sa_getcachelwp(struct proc *p) { struct sadata *sa; struct lwp *l; SCHED_ASSERT_LOCKED(); l = NULL; sa = p->p_sa; /* XXX lock sadata */ if (sa->sa_ncached > 0) { sa->sa_ncached--; l = LIST_FIRST(&sa->sa_lwpcache); LIST_REMOVE(l, l_sibling); LIST_INSERT_HEAD(&p->p_lwps, l, l_sibling); p->p_nlwps++; DPRINTFN(5,("sa_getcachelwp(%d.%d) Got LWP %d from cache.\n", p->p_pid, curlwp->l_lid, l->l_lid)); } /* XXX unlock */ return l; } void sa_unblock_userret(struct lwp *l) { struct proc *p; struct lwp *l2; struct sadata *sa; struct sadata_upcall *sau; struct sastack *sast; int f, s; p = l->l_proc; sa = p->p_sa; if (p->p_flag & P_WEXIT) return; SCHED_ASSERT_UNLOCKED(); KERNEL_PROC_LOCK(l); SA_LWP_STATE_LOCK(l, f); DPRINTFN(7,("sa_unblock_userret(%d.%d %x) \n", p->p_pid, l->l_lid, l->l_flag)); sa_setwoken(l); /* maybe NOTREACHED */ SCHED_LOCK(s); if (l != sa->sa_vp) { /* Invoke an "unblocked" upcall */ DPRINTFN(8,("sa_unblock_userret(%d.%d) unblocking\n", p->p_pid, l->l_lid)); l2 = sa_vp_repossess(l); SCHED_UNLOCK(s); if (l2 == NULL) lwp_exit(l); PHOLD(l2); sau = sadata_upcall_alloc(1); sau->sau_arg = NULL; if (p->p_flag & P_WEXIT) { sadata_upcall_free(sau); lwp_exit(l); } sast = SLIST_FIRST(&sa->sa_stackslist); KDASSERT(sast != NULL); SLIST_REMOVE_HEAD(&sa->sa_stackslist, sast_list); SLIST_NEXT(sast, sast_list) = (void *)-1; DPRINTFN(9,("sa_unblock_userret(%d.%d) using stack %p\n", l->l_proc->p_pid, l->l_lid, sast->sast_stack.ss_sp)); /* * Defer saving the event lwp's state because a * PREEMPT upcall could be on the queue already. */ if (sa_upcall0(l, SA_UPCALL_UNBLOCKED | SA_UPCALL_DEFER_EVENT, l, l2, 0, NULL, sau, &sast->sast_stack) != 0) { /* * We were supposed to deliver an UNBLOCKED * upcall, but don't have resources to do so. */ #ifdef DIAGNOSTIC printf("sa_unblock_userret: out of upcall resources" " for %d.%d\n", p->p_pid, l->l_lid); #endif sigexit(l, SIGABRT); /* NOTREACHED */ } SCHED_LOCK(s); SIMPLEQ_INSERT_TAIL(&sa->sa_upcalls, sau, sau_next); l->l_flag |= L_SA_UPCALL; l->l_flag &= ~L_SA_BLOCKING; l->l_upcallstack = NULL; sa_putcachelwp(p, l2); } SCHED_UNLOCK(s); SA_LWP_STATE_UNLOCK(l, f); KERNEL_PROC_UNLOCK(l); } void sa_upcall_userret(struct lwp *l) { struct lwp *l2, *eventq; struct proc *p; struct sadata *sa; struct sa_t **sapp, *sap; struct sadata_upcall *sau; struct sa_t self_sa; struct sa_t *sas[3], *sasp; union sau_state e_ss; struct sastack *sast; void *stack, *ap; ucontext_t u, *up; int f, i, nint, nevents, s, type; p = l->l_proc; sa = p->p_sa; SCHED_ASSERT_UNLOCKED(); KERNEL_PROC_LOCK(l); SA_LWP_STATE_LOCK(l, f); DPRINTFN(7,("sa_upcall_userret(%d.%d %x) \n", p->p_pid, l->l_lid, l->l_flag)); KDASSERT(l->l_upcallstack == NULL); SCHED_LOCK(s); if (SIMPLEQ_EMPTY(&sa->sa_upcalls) && sa->sa_wokenq_head != NULL && !SLIST_EMPTY(&sa->sa_stackslist)) { /* Invoke an "unblocked" upcall */ l2 = sa->sa_wokenq_head; sa->sa_wokenq_head = l2->l_forw; sast = SLIST_FIRST(&sa->sa_stackslist); KDASSERT(sast != NULL); SLIST_REMOVE_HEAD(&sa->sa_stackslist, sast_list); SLIST_NEXT(sast, sast_list) = (void *)-1; DPRINTFN(9,("sa_upcall_userret(%d.%d) using stack %p\n", l->l_proc->p_pid, l->l_lid, sast->sast_stack.ss_sp)); SCHED_UNLOCK(s); if (p->p_flag & P_WEXIT) lwp_exit(l); DPRINTFN(8,("sa_upcall_userret(%d.%d) unblocking %d\n", p->p_pid, l->l_lid, l2->l_lid)); sau = sadata_upcall_alloc(1); sau->sau_arg = NULL; if (p->p_flag & P_WEXIT) { sadata_upcall_free(sau); lwp_exit(l); } if (sa_upcall0(l, SA_UPCALL_UNBLOCKED, l2, l, 0, NULL, sau, &sast->sast_stack) != 0) { /* * We were supposed to deliver an UNBLOCKED * upcall, but don't have resources to do so. */ #ifdef DIAGNOSTIC printf("sa_upcall_userret: out of upcall resources" " for %d.%d\n", p->p_pid, l->l_lid); #endif sigexit(l, SIGABRT); /* NOTREACHED */ } SIMPLEQ_INSERT_TAIL(&sa->sa_upcalls, sau, sau_next); l2->l_flag &= ~L_SA_BLOCKING; l2->l_upcallstack = NULL; SCHED_LOCK(s); sa_putcachelwp(p, l2); /* PHOLD from sa_setwoken */ } SCHED_UNLOCK(s); KDASSERT(sa->sa_vp == l); if (SIMPLEQ_EMPTY(&sa->sa_upcalls)) { l->l_flag &= ~L_SA_UPCALL; SA_LWP_STATE_UNLOCK(l, f); KERNEL_PROC_UNLOCK(l); return; } sau = SIMPLEQ_FIRST(&sa->sa_upcalls); SIMPLEQ_REMOVE_HEAD(&sa->sa_upcalls, sau_next); if (sau->sau_flags & SAU_FLAG_DEFERRED_EVENT) sa_upcall_getstate(&sau->sau_event, sau->sau_event.ss_deferred.ss_lwp); if (sau->sau_flags & SAU_FLAG_DEFERRED_INTERRUPTED) sa_upcall_getstate(&sau->sau_interrupted, sau->sau_interrupted.ss_deferred.ss_lwp); stack = (void *) (((uintptr_t)sau->sau_stack.ss_sp + sau->sau_stack.ss_size) & ~ALIGNBYTES); self_sa.sa_id = l->l_lid; self_sa.sa_cpu = 0; /* XXX l->l_cpu; */ sas[0] = &self_sa; nevents = 0; nint = 0; if (sau->sau_event.ss_captured.ss_sa.sa_context != NULL) { if (copyout(&sau->sau_event.ss_captured.ss_ctx, sau->sau_event.ss_captured.ss_sa.sa_context, sizeof(ucontext_t)) != 0) { #ifdef DIAGNOSTIC printf("sa_upcall_userret(%d.%d): couldn't copyout" " context of event LWP %d\n", p->p_pid, l->l_lid, sau->sau_event.ss_captured.ss_sa.sa_id); #endif sigexit(l, SIGILL); /* NOTREACHED */ } sas[1] = &sau->sau_event.ss_captured.ss_sa; nevents = 1; } if (sau->sau_interrupted.ss_captured.ss_sa.sa_context != NULL) { KDASSERT(sau->sau_interrupted.ss_captured.ss_sa.sa_context != sau->sau_event.ss_captured.ss_sa.sa_context); if (copyout(&sau->sau_interrupted.ss_captured.ss_ctx, sau->sau_interrupted.ss_captured.ss_sa.sa_context, sizeof(ucontext_t)) != 0) { #ifdef DIAGNOSTIC printf("sa_upcall_userret(%d.%d): couldn't copyout" " context of interrupted LWP %d\n", p->p_pid, l->l_lid, sau->sau_interrupted.ss_captured.ss_sa.sa_id); #endif sigexit(l, SIGILL); /* NOTREACHED */ } sas[2] = &sau->sau_interrupted.ss_captured.ss_sa; nint = 1; } eventq = NULL; if (sau->sau_type == SA_UPCALL_UNBLOCKED) { SCHED_LOCK(s); eventq = sa->sa_wokenq_head; sa->sa_wokenq_head = NULL; SCHED_UNLOCK(s); l2 = eventq; while (l2 != NULL) { nevents++; l2 = l2->l_forw; } } /* Copy out the activation's ucontext */ u.uc_stack = sau->sau_stack; u.uc_flags = _UC_STACK; up = stack; up--; if (copyout(&u, up, sizeof(ucontext_t)) != 0) { sadata_upcall_free(sau); #ifdef DIAGNOSTIC printf("sa_upcall_userret: couldn't copyout activation" " ucontext for %d.%d\n", l->l_proc->p_pid, l->l_lid); #endif sigexit(l, SIGILL); /* NOTREACHED */ } sas[0]->sa_context = up; /* Next, copy out the sa_t's and pointers to them. */ sap = (struct sa_t *) up; sapp = (struct sa_t **) (sap - (1 + nevents + nint)); KDASSERT(nint <= 1); for (i = nevents + nint; i >= 0; i--) { sap--; sapp--; if (i == 1 + nevents) /* interrupted sa */ sasp = sas[2]; else if (i <= 1) /* self_sa and event sa */ sasp = sas[i]; else { /* extra sas */ KDASSERT(sau->sau_type == SA_UPCALL_UNBLOCKED); KDASSERT(eventq != NULL); l2 = eventq; KDASSERT(l2 != NULL); eventq = l2->l_forw; DPRINTFN(8,("sa_upcall_userret(%d.%d) unblocking extra %d\n", p->p_pid, l->l_lid, l2->l_lid)); sa_upcall_getstate(&e_ss, l2); SCHED_LOCK(s); l2->l_flag &= ~L_SA_BLOCKING; l2->l_upcallstack = NULL; sa_putcachelwp(p, l2); /* PHOLD from sa_setwoken */ SCHED_UNLOCK(s); if (copyout(&e_ss.ss_captured.ss_ctx, e_ss.ss_captured.ss_sa.sa_context, sizeof(ucontext_t)) != 0) { #ifdef DIAGNOSTIC printf("sa_upcall_userret(%d.%d): couldn't copyout" " context of event LWP %d\n", p->p_pid, l->l_lid, e_ss.ss_captured.ss_sa.sa_id); #endif sigexit(l, SIGILL); /* NOTREACHED */ } sasp = &e_ss.ss_captured.ss_sa; } if ((copyout(sasp, sap, sizeof(struct sa_t)) != 0) || (copyout(&sap, sapp, sizeof(struct sa_t *)) != 0)) { /* Copying onto the stack didn't work. Die. */ sadata_upcall_free(sau); #ifdef DIAGNOSTIC printf("sa_upcall_userret: couldn't copyout sa_t " "%d for %d.%d\n", i, p->p_pid, l->l_lid); #endif sigexit(l, SIGILL); /* NOTREACHED */ } } KDASSERT(eventq == NULL); /* Copy out the arg, if any */ /* xxx assume alignment works out; everything so far has been * a structure, so... */ if (sau->sau_arg) { ap = (char *)sapp - sau->sau_argsize; stack = ap; if (copyout(sau->sau_arg, ap, sau->sau_argsize) != 0) { /* Copying onto the stack didn't work. Die. */ sadata_upcall_free(sau); #ifdef DIAGNOSTIC printf("sa_upcall_userret(%d.%d): couldn't copyout" " sadata_upcall arg %p size %ld to %p \n", p->p_pid, l->l_lid, sau->sau_arg, (long) sau->sau_argsize, ap); #endif sigexit(l, SIGILL); /* NOTREACHED */ } } else { ap = 0; stack = sapp; } type = sau->sau_type; sadata_upcall_free(sau); DPRINTFN(7,("sa_upcall_userret(%d.%d): type %d\n", p->p_pid, l->l_lid, type)); cpu_upcall(l, type, nevents, nint, sapp, ap, stack, sa->sa_upcall); if (sa->sa_wokenq_head != NULL) l->l_flag |= L_SA_UPCALL; else if (SIMPLEQ_EMPTY(&sa->sa_upcalls)) l->l_flag &= ~L_SA_UPCALL; SA_LWP_STATE_UNLOCK(l, f); KERNEL_PROC_UNLOCK(l); } static void sa_setwoken(struct lwp *l) { struct lwp *l2, *vp_lwp; struct proc *p; struct sadata *sa; int s; SCHED_LOCK(s); if ((l->l_flag & L_SA_BLOCKING) == 0) { SCHED_UNLOCK(s); return; } p = l->l_proc; sa = p->p_sa; vp_lwp = sa->sa_vp; l2 = NULL; KDASSERT(vp_lwp != NULL); DPRINTFN(3,("sa_setwoken(%d.%d) woken, flags %x, vp %d\n", l->l_proc->p_pid, l->l_lid, l->l_flag, vp_lwp->l_lid)); if (l->l_upcallstack && l->l_upcallstack->sast_blocker == NULL) { DPRINTFN(11,("sa_setwoken(%d.%d) recycle\n", l->l_proc->p_pid, l->l_lid)); l->l_flag &= ~(L_SA_UPCALL|L_SA_BLOCKING); l->l_flag |= L_SA; l->l_upcallstack = NULL; p->p_nrlwps--; PHOLD(l); sa_putcachelwp(p, l); mi_switch(l, NULL); /* mostly NOTREACHED */ SCHED_ASSERT_UNLOCKED(); splx(s); KDASSERT(p->p_flag & P_WEXIT); lwp_exit(l); } #if notyet if (vp_lwp->l_flag & L_SA_IDLE) { KDASSERT((vp_lwp->l_flag & L_SA_UPCALL) == 0); KDASSERT(sa->sa_wokenq_head == NULL); DPRINTFN(3,("sa_setwoken(%d.%d) repossess: idle vp_lwp %d state %d\n", l->l_proc->p_pid, l->l_lid, vp_lwp->l_lid, vp_lwp->l_stat)); vp_lwp->l_flag &= ~L_SA_IDLE; SCHED_UNLOCK(s); return; } #endif DPRINTFN(3,("sa_setwoken(%d.%d) put on wokenq: vp_lwp %d state %d\n", l->l_proc->p_pid, l->l_lid, vp_lwp->l_lid, vp_lwp->l_stat)); PHOLD(l); if (sa->sa_wokenq_head == NULL) sa->sa_wokenq_head = l; else *sa->sa_wokenq_tailp = l; *(sa->sa_wokenq_tailp = &l->l_forw) = NULL; switch (vp_lwp->l_stat) { case LSONPROC: if (vp_lwp->l_flag & L_SA_UPCALL) break; vp_lwp->l_flag |= L_SA_UPCALL; if (vp_lwp->l_flag & L_SA_YIELD) break; /* XXX IPI vp_lwp->l_cpu */ break; case LSSLEEP: if (vp_lwp->l_flag & L_SA_IDLE) { vp_lwp->l_flag &= ~L_SA_IDLE; vp_lwp->l_flag |= L_SA_UPCALL; setrunnable(vp_lwp); break; } vp_lwp->l_flag |= L_SA_UPCALL; break; case LSSUSPENDED: #ifdef DIAGNOSTIC printf("sa_setwoken(%d.%d) vp lwp %d LSSUSPENDED\n", l->l_proc->p_pid, l->l_lid, vp_lwp->l_lid); #endif break; case LSSTOP: vp_lwp->l_flag |= L_SA_UPCALL; break; case LSRUN: if (vp_lwp->l_flag & L_SA_UPCALL) break; vp_lwp->l_flag |= L_SA_UPCALL; if (vp_lwp->l_flag & L_SA_YIELD) break; if (vp_lwp->l_slptime > 1) { void updatepri(struct lwp *); updatepri(vp_lwp); } vp_lwp->l_slptime = 0; if (vp_lwp->l_flag & L_INMEM) { if (vp_lwp->l_cpu == curcpu()) l2 = vp_lwp; else need_resched(vp_lwp->l_cpu); } else sched_wakeup(&proc0); break; default: panic("sa_vp LWP not sleeping/onproc/runnable"); } if (l->l_upcallstack) { if (l->l_upcallstack->sast_blocker != l) sched_wakeup(&l->l_upcallstack); l->l_upcallstack->sast_blocker = NULL; } l->l_stat = LSSUSPENDED; p->p_nrlwps--; mi_switch(l, l2); /* maybe NOTREACHED */ SCHED_ASSERT_UNLOCKED(); splx(s); if (p->p_flag & P_WEXIT) lwp_exit(l); } static struct lwp * sa_vp_repossess(struct lwp *l) { struct lwp *l2; struct proc *p = l->l_proc; struct sadata *sa = p->p_sa; SCHED_ASSERT_LOCKED(); /* * Put ourselves on the virtual processor and note that the * previous occupant of that position was interrupted. */ l2 = sa->sa_vp; sa->sa_vp = l; if (l2->l_flag & L_SA_YIELD) l2->l_flag &= ~(L_SA_YIELD|L_SA_IDLE); DPRINTFN(1,("sa_vp_repossess(%d.%d) vp lwp %d state %d\n", p->p_pid, l->l_lid, l2->l_lid, l2->l_stat)); KDASSERT(l2 != l); if (l2) { switch (l2->l_stat) { case LSRUN: remrunqueue(l2); p->p_nrlwps--; break; case LSSLEEP: unsleep(l2); l2->l_flag &= ~L_SINTR; break; case LSSUSPENDED: #ifdef DIAGNOSTIC printf("sa_vp_repossess(%d.%d) vp lwp %d LSSUSPENDED\n", l->l_proc->p_pid, l->l_lid, l2->l_lid); #endif break; #ifdef DIAGNOSTIC default: panic("SA VP %d.%d is in state %d, not running" " or sleeping\n", p->p_pid, l2->l_lid, l2->l_stat); #endif } l2->l_stat = LSSUSPENDED; } return l2; } #ifdef DEBUG int debug_print_sa(struct proc *); int debug_print_lwp(struct lwp *); int debug_print_proc(int); int debug_print_proc(int pid) { struct proc *p; p = pfind(pid); if (p == NULL) printf("No process %d\n", pid); else debug_print_sa(p); return 0; } int debug_print_sa(struct proc *p) { struct lwp *l; struct sadata *sa; printf("Process %d (%s), state %d, address %p, flags %x\n", p->p_pid, p->p_comm, p->p_stat, p, p->p_flag); printf("LWPs: %d (%d running, %d zombies)\n", p->p_nlwps, p->p_nrlwps, p->p_nzlwps); LIST_FOREACH(l, &p->p_lwps, l_sibling) debug_print_lwp(l); sa = p->p_sa; if (sa) { if (sa->sa_vp) printf("SA VP: %d %s\n", sa->sa_vp->l_lid, sa->sa_vp->l_flag & L_SA_YIELD ? (sa->sa_vp->l_flag & L_SA_IDLE ? "idle" : "yielding") : ""); printf("SAs: %d cached LWPs\n", sa->sa_ncached); LIST_FOREACH(l, &sa->sa_lwpcache, l_sibling) debug_print_lwp(l); } return 0; } int debug_print_lwp(struct lwp *l) { printf("LWP %d address %p ", l->l_lid, l); printf("state %d flags %x ", l->l_stat, l->l_flag); if (l->l_wchan) printf("wait %p %s", l->l_wchan, l->l_wmesg); printf("\n"); return 0; } #endif