diff options
Diffstat (limited to 'sys/vm/vm_glue.c')
| -rw-r--r-- | sys/vm/vm_glue.c | 683 |
1 files changed, 683 insertions, 0 deletions
diff --git a/sys/vm/vm_glue.c b/sys/vm/vm_glue.c new file mode 100644 index 0000000..2fc7aba --- /dev/null +++ b/sys/vm/vm_glue.c @@ -0,0 +1,683 @@ +/* + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * The Mach Operating System project at Carnegie-Mellon University. + * + * 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 University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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. + * + * from: @(#)vm_glue.c 8.6 (Berkeley) 1/5/94 + * + * + * Copyright (c) 1987, 1990 Carnegie-Mellon University. + * All rights reserved. + * + * Permission to use, copy, modify and distribute this software and + * its documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND + * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie the + * rights to redistribute these changes. + * + * $Id: vm_glue.c,v 1.5 1994/08/09 10:42:41 davidg Exp $ + */ + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/proc.h> +#include <sys/resourcevar.h> +#include <sys/buf.h> +#include <sys/user.h> + +#include <sys/kernel.h> +#include <sys/dkstat.h> + +#include <vm/vm.h> +#include <vm/vm_page.h> +#include <vm/vm_pageout.h> +#include <vm/vm_kern.h> + +#include <machine/stdarg.h> + +extern char kstack[]; +int avefree = 0; /* XXX */ +int readbuffers = 0; /* XXX allow kgdb to read kernel buffer pool */ +/* vm_map_t upages_map; */ + +int +kernacc(addr, len, rw) + caddr_t addr; + int len, rw; +{ + boolean_t rv; + vm_offset_t saddr, eaddr; + vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE; + + saddr = trunc_page(addr); + eaddr = round_page(addr+len); + rv = vm_map_check_protection(kernel_map, saddr, eaddr, prot); + return(rv == TRUE); +} + +int +useracc(addr, len, rw) + caddr_t addr; + int len, rw; +{ + boolean_t rv; + vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE; + + /* + * XXX - check separately to disallow access to user area and user + * page tables - they are in the map. + * + * XXX - VM_MAXUSER_ADDRESS is an end address, not a max. It was + * once only used (as an end address) in trap.c. Use it as an end + * address here too. This bogusness has spread. I just fixed + * where it was used as a max in vm_mmap.c. + */ + if ((vm_offset_t) addr + len > /* XXX */ VM_MAXUSER_ADDRESS + || (vm_offset_t) addr + len < (vm_offset_t) addr) { + return (FALSE); + } + + rv = vm_map_check_protection(&curproc->p_vmspace->vm_map, + trunc_page(addr), round_page(addr+len), prot); + return(rv == TRUE); +} + +#ifdef KGDB +/* + * Change protections on kernel pages from addr to addr+len + * (presumably so debugger can plant a breakpoint). + * All addresses are assumed to reside in the Sysmap, + */ +chgkprot(addr, len, rw) + register caddr_t addr; + int len, rw; +{ + vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE; + + vm_map_protect(kernel_map, trunc_page(addr), + round_page(addr+len), prot, FALSE); +} +#endif +void +vslock(addr, len) + caddr_t addr; + u_int len; +{ + vm_map_pageable(&curproc->p_vmspace->vm_map, trunc_page(addr), + round_page(addr+len), FALSE); +} + +void +vsunlock(addr, len, dirtied) + caddr_t addr; + u_int len; + int dirtied; +{ +#ifdef lint + dirtied++; +#endif lint + vm_map_pageable(&curproc->p_vmspace->vm_map, trunc_page(addr), + round_page(addr+len), TRUE); +} + +/* + * Implement fork's actions on an address space. + * Here we arrange for the address space to be copied or referenced, + * allocate a user struct (pcb and kernel stack), then call the + * machine-dependent layer to fill those in and make the new process + * ready to run. + * NOTE: the kernel stack may be at a different location in the child + * process, and thus addresses of automatic variables may be invalid + * after cpu_fork returns in the child process. We do nothing here + * after cpu_fork returns. + */ +int +vm_fork(p1, p2, isvfork) + register struct proc *p1, *p2; + int isvfork; +{ + register struct user *up; + vm_offset_t addr, ptaddr; + int i; + struct vm_map *vp; + + while( cnt.v_free_count < cnt.v_free_min) + VM_WAIT; + + /* + * avoid copying any of the parent's pagetables or other per-process + * objects that reside in the map by marking all of them non-inheritable + */ + (void)vm_map_inherit(&p1->p_vmspace->vm_map, + UPT_MIN_ADDRESS - UPAGES * NBPG, VM_MAX_ADDRESS, VM_INHERIT_NONE); + p2->p_vmspace = vmspace_fork(p1->p_vmspace); + +#ifdef SYSVSHM + if (p1->p_vmspace->vm_shm) + shmfork(p1, p2, isvfork); +#endif + + /* + * Allocate a wired-down (for now) pcb and kernel stack for the process + */ + + addr = (vm_offset_t) kstack; + + vp = &p2->p_vmspace->vm_map; + + /* ream out old pagetables and kernel stack */ + (void)vm_deallocate(vp, addr, UPT_MAX_ADDRESS - addr); + + /* get new pagetables and kernel stack */ + (void)vm_allocate(vp, &addr, UPT_MAX_ADDRESS - addr, FALSE); + + /* force in the page table encompassing the UPAGES */ + ptaddr = trunc_page((u_int)vtopte(addr)); + vm_map_pageable(vp, ptaddr, ptaddr + NBPG, FALSE); + + /* and force in (demand-zero) the UPAGES */ + vm_map_pageable(vp, addr, addr + UPAGES * NBPG, FALSE); + + /* get a kernel virtual address for the UPAGES for this proc */ + up = (struct user *)kmem_alloc_pageable(kernel_map, UPAGES * NBPG); + + /* and force-map the upages into the kernel pmap */ + for (i = 0; i < UPAGES; i++) + pmap_enter(vm_map_pmap(kernel_map), + ((vm_offset_t) up) + NBPG * i, + pmap_extract(vp->pmap, addr + NBPG * i), + VM_PROT_READ|VM_PROT_WRITE, 1); + + /* and allow the UPAGES page table entry to be paged (at the vm system level) */ + vm_map_pageable(vp, ptaddr, ptaddr + NBPG, TRUE); + + p2->p_addr = up; + + /* + * p_stats and p_sigacts currently point at fields + * in the user struct but not at &u, instead at p_addr. + * Copy p_sigacts and parts of p_stats; zero the rest + * of p_stats (statistics). + */ + p2->p_stats = &up->u_stats; + p2->p_sigacts = &up->u_sigacts; + up->u_sigacts = *p1->p_sigacts; + bzero(&up->u_stats.pstat_startzero, + (unsigned) ((caddr_t)&up->u_stats.pstat_endzero - + (caddr_t)&up->u_stats.pstat_startzero)); + bcopy(&p1->p_stats->pstat_startcopy, &up->u_stats.pstat_startcopy, + ((caddr_t)&up->u_stats.pstat_endcopy - + (caddr_t)&up->u_stats.pstat_startcopy)); + + + /* + * cpu_fork will copy and update the kernel stack and pcb, + * and make the child ready to run. It marks the child + * so that it can return differently than the parent. + * It returns twice, once in the parent process and + * once in the child. + */ + return (cpu_fork(p1, p2)); +} + +/* + * Set default limits for VM system. + * Called for proc 0, and then inherited by all others. + */ +void +vm_init_limits(p) + register struct proc *p; +{ + int rss_limit; + + /* + * Set up the initial limits on process VM. + * Set the maximum resident set size to be half + * of (reasonably) available memory. Since this + * is a soft limit, it comes into effect only + * when the system is out of memory - half of + * main memory helps to favor smaller processes, + * and reduces thrashing of the object cache. + */ + p->p_rlimit[RLIMIT_STACK].rlim_cur = DFLSSIZ; + p->p_rlimit[RLIMIT_STACK].rlim_max = MAXSSIZ; + p->p_rlimit[RLIMIT_DATA].rlim_cur = DFLDSIZ; + p->p_rlimit[RLIMIT_DATA].rlim_max = MAXDSIZ; + /* limit the limit to no less than 128K */ + rss_limit = max(cnt.v_free_count / 2, 32); + p->p_rlimit[RLIMIT_RSS].rlim_cur = ptoa(rss_limit); + p->p_rlimit[RLIMIT_RSS].rlim_max = RLIM_INFINITY; +} + +#ifdef DEBUG +int enableswap = 1; +int swapdebug = 0; +#define SDB_FOLLOW 1 +#define SDB_SWAPIN 2 +#define SDB_SWAPOUT 4 +#endif + +void +faultin(p) +struct proc *p; +{ + vm_offset_t i; + vm_offset_t vaddr, ptaddr; + vm_offset_t v, v1; + struct user *up; + int s; + int opflag; + + if ((p->p_flag & P_INMEM) == 0) { + int rv0, rv1; + vm_map_t map; + + ++p->p_lock; + + map = &p->p_vmspace->vm_map; + /* force the page table encompassing the kernel stack (upages) */ + ptaddr = trunc_page((u_int)vtopte(kstack)); + vm_map_pageable(map, ptaddr, ptaddr + NBPG, FALSE); + + /* wire in the UPAGES */ + vm_map_pageable(map, (vm_offset_t) kstack, + (vm_offset_t) kstack + UPAGES * NBPG, FALSE); + + /* and map them nicely into the kernel pmap */ + for (i = 0; i < UPAGES; i++) { + vm_offset_t off = i * NBPG; + vm_offset_t pa = (vm_offset_t) + pmap_extract(&p->p_vmspace->vm_pmap, + (vm_offset_t) kstack + off); + pmap_enter(vm_map_pmap(kernel_map), + ((vm_offset_t)p->p_addr) + off, + pa, VM_PROT_READ|VM_PROT_WRITE, 1); + } + + /* and let the page table pages go (at least above pmap level) */ + vm_map_pageable(map, ptaddr, ptaddr + NBPG, TRUE); + + s = splhigh(); + + if (p->p_stat == SRUN) + setrunqueue(p); + + p->p_flag |= P_INMEM; + + /* undo the effect of setting SLOCK above */ + --p->p_lock; + splx(s); + + } + +} + +int swapinreq; +int percentactive; +/* + * This swapin algorithm attempts to swap-in processes only if there + * is enough space for them. Of course, if a process waits for a long + * time, it will be swapped in anyway. + */ +void +scheduler() +{ + register struct proc *p; + register int pri; + struct proc *pp; + int ppri; + vm_offset_t addr; + int lastidle, lastrun; + int curidle, currun; + int forceload; + int percent; + int ntries; + + lastidle = 0; + lastrun = 0; + +loop: + ntries = 0; + + curidle = cp_time[CP_IDLE]; + currun = cp_time[CP_USER] + cp_time[CP_SYS] + cp_time[CP_NICE]; + percent = (100*(currun-lastrun)) / ( 1 + (currun-lastrun) + (curidle-lastidle)); + lastrun = currun; + lastidle = curidle; + if( percent > 100) + percent = 100; + percentactive = percent; + + if( percentactive < 25) + forceload = 1; + else + forceload = 0; + +loop1: + pp = NULL; + ppri = INT_MIN; + for (p = (struct proc *)allproc; p != NULL; p = p->p_next) { + if (p->p_stat == SRUN && (p->p_flag & P_INMEM) == 0) { + int mempri; + pri = p->p_swtime + p->p_slptime - p->p_nice * 8; + mempri = pri > 0 ? pri : 0; + /* + * if this process is higher priority and there is + * enough space, then select this process instead + * of the previous selection. + */ + if (pri > ppri && + (((cnt.v_free_count + (mempri * (4*PAGE_SIZE) / PAGE_SIZE) >= (p->p_vmspace->vm_swrss)) || (ntries > 0 && forceload)))) { + pp = p; + ppri = pri; + } + } + } + + if ((pp == NULL) && (ntries == 0) && forceload) { + ++ntries; + goto loop1; + } + + /* + * Nothing to do, back to sleep + */ + if ((p = pp) == NULL) { + tsleep((caddr_t)&proc0, PVM, "sched", 0); + goto loop; + } + + /* + * We would like to bring someone in. (only if there is space). + */ +/* + printf("swapin: %d, free: %d, res: %d, min: %d\n", + p->p_pid, cnt.v_free_count, cnt.v_free_reserved, cnt.v_free_min); +*/ + (void) splhigh(); + if ((forceload && (cnt.v_free_count > (cnt.v_free_reserved + UPAGES + 1))) || + (cnt.v_free_count >= cnt.v_free_min)) { + spl0(); + faultin(p); + p->p_swtime = 0; + goto loop; + } + /* + * log the memory shortage + */ + swapinreq += p->p_vmspace->vm_swrss; + /* + * Not enough memory, jab the pageout daemon and wait til the + * coast is clear. + */ + if( cnt.v_free_count < cnt.v_free_min) { + VM_WAIT; + } else { + tsleep((caddr_t)&proc0, PVM, "sched", 0); + } + (void) spl0(); + goto loop; +} + +#define swappable(p) \ + (((p)->p_lock == 0) && \ + ((p)->p_flag & (P_TRACED|P_NOSWAP|P_SYSTEM|P_INMEM|P_WEXIT|P_PHYSIO)) == P_INMEM) + +extern int vm_pageout_free_min; +/* + * Swapout is driven by the pageout daemon. Very simple, we find eligible + * procs and unwire their u-areas. We try to always "swap" at least one + * process in case we need the room for a swapin. + * If any procs have been sleeping/stopped for at least maxslp seconds, + * they are swapped. Else, we swap the longest-sleeping or stopped process, + * if any, otherwise the longest-resident process. + */ +void +swapout_threads() +{ + register struct proc *p; + struct proc *outp, *outp2; + int outpri, outpri2; + int tpri; + int didswap = 0; + int swapneeded = swapinreq; + extern int maxslp; + int runnablenow; + int s; + +swapmore: + runnablenow = 0; + outp = outp2 = NULL; + outpri = outpri2 = INT_MIN; + for (p = (struct proc *)allproc; p != NULL; p = p->p_next) { + if (!swappable(p)) + continue; + switch (p->p_stat) { + case SRUN: + ++runnablenow; + /* + * count the process as being in a runnable state + */ + if ((tpri = p->p_swtime + p->p_nice * 8) > outpri2) { + outp2 = p; + outpri2 = tpri; + } + continue; + + case SSLEEP: + case SSTOP: + /* + * do not swapout a process that is waiting for VM datastructures + * there is a possible deadlock. + */ + if (!lock_try_write( &p->p_vmspace->vm_map.lock)) { + continue; + } + vm_map_unlock( &p->p_vmspace->vm_map); + if (p->p_slptime > maxslp) { + swapout(p); + didswap++; + } else if ((tpri = p->p_slptime + p->p_nice * 8) > outpri) { + outp = p; + outpri = tpri ; + } + continue; + } + } + /* + * We swapout only if there are more than two runnable processes or if + * another process needs some space to swapin. + */ + if ((swapinreq || ((percentactive > 90) && (runnablenow > 2))) && + (((cnt.v_free_count + cnt.v_inactive_count) <= (cnt.v_free_target + cnt.v_inactive_target)) || + (cnt.v_free_count < cnt.v_free_min))) { + if ((p = outp) == 0) { + p = outp2; + } + + if (p) { + swapout(p); + didswap = 1; + } + } + + /* + * if we previously had found a process to swapout, and we need to swapout + * more then try again. + */ +#if 0 + if( p && swapinreq) + goto swapmore; +#endif + + /* + * If we swapped something out, and another process needed memory, + * then wakeup the sched process. + */ + if (didswap) { + if (swapneeded) + wakeup((caddr_t)&proc0); + swapinreq = 0; + } +} + +void +swapout(p) + register struct proc *p; +{ + vm_offset_t addr; + struct pmap *pmap = &p->p_vmspace->vm_pmap; + vm_map_t map = &p->p_vmspace->vm_map; + vm_offset_t ptaddr; + int i; + + ++p->p_stats->p_ru.ru_nswap; + /* + * remember the process resident count + */ + p->p_vmspace->vm_swrss = + p->p_vmspace->vm_pmap.pm_stats.resident_count; + /* + * and decrement the amount of needed space + */ + swapinreq -= min(swapinreq, p->p_vmspace->vm_pmap.pm_stats.resident_count); + + (void) splhigh(); + p->p_flag &= ~P_INMEM; + if (p->p_stat == SRUN) + remrq(p); + (void) spl0(); + + ++p->p_lock; +/* let the upages be paged */ + pmap_remove(vm_map_pmap(kernel_map), + (vm_offset_t) p->p_addr, ((vm_offset_t) p->p_addr) + UPAGES * NBPG); + + vm_map_pageable(map, (vm_offset_t) kstack, + (vm_offset_t) kstack + UPAGES * NBPG, TRUE); + + --p->p_lock; + p->p_swtime = 0; +} + +/* + * The rest of these routines fake thread handling + */ + +#ifndef assert_wait +void +assert_wait(event, ruptible) + int event; + boolean_t ruptible; +{ +#ifdef lint + ruptible++; +#endif + curproc->p_thread = event; +} +#endif + +void +thread_block(char *msg) +{ + if (curproc->p_thread) + tsleep((caddr_t)curproc->p_thread, PVM, msg, 0); +} + + +void +thread_sleep_(event, lock, wmesg) + int event; + simple_lock_t lock; + char *wmesg; +{ + + curproc->p_thread = event; + simple_unlock(lock); + if (curproc->p_thread) { + tsleep((caddr_t)event, PVM, wmesg, 0); + } +} + +#ifndef thread_wakeup +void +thread_wakeup(event) + int event; +{ + wakeup((caddr_t)event); +} +#endif + +/* + * DEBUG stuff + */ + +int indent = 0; + +#include <machine/stdarg.h> /* see subr_prf.c */ + +/*ARGSUSED2*/ +void +#if __STDC__ +iprintf(const char *fmt, ...) +#else +iprintf(fmt /* , va_alist */) + char *fmt; + /* va_dcl */ +#endif +{ + register int i; + va_list ap; + + for (i = indent; i >= 8; i -= 8) + printf("\t"); + while (--i >= 0) + printf(" "); + va_start(ap, fmt); + printf("%r", fmt, ap); + va_end(ap); +} |
