1096e95c0SMatthew Dillon /* 28e7c4729SMatthew Dillon * (MPSAFE) 38e7c4729SMatthew Dillon * 49de48eadSMatthew Dillon * Copyright (c) 2010,2019 The DragonFly Project. All rights reserved. 5096e95c0SMatthew Dillon * 6096e95c0SMatthew Dillon * This code is derived from software contributed to The DragonFly Project 7096e95c0SMatthew Dillon * by Matthew Dillon <dillon@backplane.com> 8096e95c0SMatthew Dillon * 9096e95c0SMatthew Dillon * Redistribution and use in source and binary forms, with or without 10096e95c0SMatthew Dillon * modification, are permitted provided that the following conditions 11096e95c0SMatthew Dillon * are met: 12096e95c0SMatthew Dillon * 13096e95c0SMatthew Dillon * 1. Redistributions of source code must retain the above copyright 14096e95c0SMatthew Dillon * notice, this list of conditions and the following disclaimer. 15096e95c0SMatthew Dillon * 2. Redistributions in binary form must reproduce the above copyright 16096e95c0SMatthew Dillon * notice, this list of conditions and the following disclaimer in 17096e95c0SMatthew Dillon * the documentation and/or other materials provided with the 18096e95c0SMatthew Dillon * distribution. 19096e95c0SMatthew Dillon * 3. Neither the name of The DragonFly Project nor the names of its 20096e95c0SMatthew Dillon * contributors may be used to endorse or promote products derived 21096e95c0SMatthew Dillon * from this software without specific, prior written permission. 22096e95c0SMatthew Dillon * 23096e95c0SMatthew Dillon * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24096e95c0SMatthew Dillon * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25096e95c0SMatthew Dillon * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 26096e95c0SMatthew Dillon * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 27096e95c0SMatthew Dillon * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 28096e95c0SMatthew Dillon * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 29096e95c0SMatthew Dillon * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 30096e95c0SMatthew Dillon * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 31096e95c0SMatthew Dillon * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 32096e95c0SMatthew Dillon * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 33096e95c0SMatthew Dillon * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34096e95c0SMatthew Dillon * SUCH DAMAGE. 35096e95c0SMatthew Dillon */ 36096e95c0SMatthew Dillon 37096e95c0SMatthew Dillon /* 38096e95c0SMatthew Dillon * Implement the swapcache daemon. When enabled swap is assumed to be 39096e95c0SMatthew Dillon * configured on a fast storage device such as a SSD. Swap is assigned 40096e95c0SMatthew Dillon * to clean vnode-backed pages in the inactive queue, clustered by object 41096e95c0SMatthew Dillon * if possible, and written out. The swap assignment sticks around even 42096e95c0SMatthew Dillon * after the underlying pages have been recycled. 43096e95c0SMatthew Dillon * 44096e95c0SMatthew Dillon * The daemon manages write bandwidth based on sysctl settings to control 45096e95c0SMatthew Dillon * wear on the SSD. 46096e95c0SMatthew Dillon * 47096e95c0SMatthew Dillon * The vnode strategy code will check for the swap assignments and divert 483ffc7051SMatthew Dillon * reads to the swap device when the data is present in the swapcache. 49096e95c0SMatthew Dillon * 50096e95c0SMatthew Dillon * This operates on both regular files and the block device vnodes used by 51096e95c0SMatthew Dillon * filesystems to manage meta-data. 52096e95c0SMatthew Dillon */ 53096e95c0SMatthew Dillon 54096e95c0SMatthew Dillon #include "opt_vm.h" 55096e95c0SMatthew Dillon #include <sys/param.h> 56096e95c0SMatthew Dillon #include <sys/systm.h> 57096e95c0SMatthew Dillon #include <sys/kernel.h> 58096e95c0SMatthew Dillon #include <sys/proc.h> 59096e95c0SMatthew Dillon #include <sys/kthread.h> 60096e95c0SMatthew Dillon #include <sys/resourcevar.h> 61096e95c0SMatthew Dillon #include <sys/signalvar.h> 62096e95c0SMatthew Dillon #include <sys/vnode.h> 63096e95c0SMatthew Dillon #include <sys/vmmeter.h> 64096e95c0SMatthew Dillon #include <sys/sysctl.h> 65497524bfSMatthew Dillon #include <sys/eventhandler.h> 66096e95c0SMatthew Dillon 67096e95c0SMatthew Dillon #include <vm/vm.h> 68096e95c0SMatthew Dillon #include <vm/vm_param.h> 69096e95c0SMatthew Dillon #include <sys/lock.h> 70096e95c0SMatthew Dillon #include <vm/vm_object.h> 71096e95c0SMatthew Dillon #include <vm/vm_page.h> 72096e95c0SMatthew Dillon #include <vm/vm_map.h> 73096e95c0SMatthew Dillon #include <vm/vm_pageout.h> 74096e95c0SMatthew Dillon #include <vm/vm_pager.h> 75096e95c0SMatthew Dillon #include <vm/swap_pager.h> 76096e95c0SMatthew Dillon #include <vm/vm_extern.h> 77096e95c0SMatthew Dillon 78b12defdcSMatthew Dillon #include <sys/spinlock2.h> 79096e95c0SMatthew Dillon #include <vm/vm_page2.h> 80096e95c0SMatthew Dillon 819de48eadSMatthew Dillon struct swmarker { 829de48eadSMatthew Dillon struct vm_object dummy_obj; 839de48eadSMatthew Dillon struct vm_object *save_obj; 849de48eadSMatthew Dillon vm_ooffset_t save_off; 859de48eadSMatthew Dillon }; 869de48eadSMatthew Dillon 879de48eadSMatthew Dillon typedef struct swmarker swmarker_t; 889de48eadSMatthew Dillon 89096e95c0SMatthew Dillon /* the kernel process "vm_pageout"*/ 90aabd5ce8SMatthew Dillon static int vm_swapcached_flush (vm_page_t m, int isblkdev); 913ffc7051SMatthew Dillon static int vm_swapcache_test(vm_page_t m); 9264949baaSMatthew Dillon static int vm_swapcache_writing_heuristic(void); 9364949baaSMatthew Dillon static int vm_swapcache_writing(vm_page_t marker, int count, int scount); 949de48eadSMatthew Dillon static void vm_swapcache_cleaning(swmarker_t *marker, 95fde6be6aSMatthew Dillon struct vm_object_hash **swindexp); 969de48eadSMatthew Dillon static void vm_swapcache_movemarker(swmarker_t *marker, 97fde6be6aSMatthew Dillon struct vm_object_hash *swindex, vm_object_t object); 98096e95c0SMatthew Dillon struct thread *swapcached_thread; 99096e95c0SMatthew Dillon 100096e95c0SMatthew Dillon SYSCTL_NODE(_vm, OID_AUTO, swapcache, CTLFLAG_RW, NULL, NULL); 101096e95c0SMatthew Dillon 102c504e38eSMatthew Dillon int vm_swapcache_read_enable; 103b396bb03SMatthew Dillon static long vm_swapcache_wtrigger; 104096e95c0SMatthew Dillon static int vm_swapcache_sleep; 10564949baaSMatthew Dillon static int vm_swapcache_maxscan = PQ_L2_SIZE * 8; 10664949baaSMatthew Dillon static int vm_swapcache_maxlaunder = PQ_L2_SIZE * 4; 107096e95c0SMatthew Dillon static int vm_swapcache_data_enable = 0; 108096e95c0SMatthew Dillon static int vm_swapcache_meta_enable = 0; 109e9b56058SMatthew Dillon static int vm_swapcache_maxswappct = 75; 110e527fb6bSMatthew Dillon static int vm_swapcache_hysteresis; 11164949baaSMatthew Dillon static int vm_swapcache_min_hysteresis; 112d4d9221dSMatthew Dillon int vm_swapcache_use_chflags = 0; /* require chflags cache */ 1133ffc7051SMatthew Dillon static int64_t vm_swapcache_minburst = 10000000LL; /* 10MB */ 1143ffc7051SMatthew Dillon static int64_t vm_swapcache_curburst = 4000000000LL; /* 4G after boot */ 1153ffc7051SMatthew Dillon static int64_t vm_swapcache_maxburst = 2000000000LL; /* 2G nominal max */ 1163ffc7051SMatthew Dillon static int64_t vm_swapcache_accrate = 100000LL; /* 100K/s */ 117096e95c0SMatthew Dillon static int64_t vm_swapcache_write_count; 1183ffc7051SMatthew Dillon static int64_t vm_swapcache_maxfilesize; 119f5f6d247SMatthew Dillon static int64_t vm_swapcache_cleanperobj = 16*1024*1024; 120096e95c0SMatthew Dillon 121096e95c0SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, maxlaunder, 122096e95c0SMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxlaunder, 0, ""); 1230bf81261SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, maxscan, 1240bf81261SMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxscan, 0, ""); 125c504e38eSMatthew Dillon 126096e95c0SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, data_enable, 127096e95c0SMatthew Dillon CTLFLAG_RW, &vm_swapcache_data_enable, 0, ""); 128096e95c0SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, meta_enable, 129096e95c0SMatthew Dillon CTLFLAG_RW, &vm_swapcache_meta_enable, 0, ""); 130c504e38eSMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, read_enable, 131c504e38eSMatthew Dillon CTLFLAG_RW, &vm_swapcache_read_enable, 0, ""); 132e9b56058SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, maxswappct, 133e9b56058SMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxswappct, 0, ""); 134e527fb6bSMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, hysteresis, 13564949baaSMatthew Dillon CTLFLAG_RD, &vm_swapcache_hysteresis, 0, ""); 13664949baaSMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, min_hysteresis, 13764949baaSMatthew Dillon CTLFLAG_RW, &vm_swapcache_min_hysteresis, 0, ""); 138e9b56058SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, use_chflags, 139e9b56058SMatthew Dillon CTLFLAG_RW, &vm_swapcache_use_chflags, 0, ""); 140c504e38eSMatthew Dillon 1413ffc7051SMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, minburst, 1423ffc7051SMatthew Dillon CTLFLAG_RW, &vm_swapcache_minburst, 0, ""); 143c504e38eSMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, curburst, 144c504e38eSMatthew Dillon CTLFLAG_RW, &vm_swapcache_curburst, 0, ""); 145c504e38eSMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, maxburst, 146c504e38eSMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxburst, 0, ""); 1473ffc7051SMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, maxfilesize, 1483ffc7051SMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxfilesize, 0, ""); 149c504e38eSMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, accrate, 150c504e38eSMatthew Dillon CTLFLAG_RW, &vm_swapcache_accrate, 0, ""); 151096e95c0SMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, write_count, 152096e95c0SMatthew Dillon CTLFLAG_RW, &vm_swapcache_write_count, 0, ""); 153f5f6d247SMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, cleanperobj, 154f5f6d247SMatthew Dillon CTLFLAG_RW, &vm_swapcache_cleanperobj, 0, ""); 155096e95c0SMatthew Dillon 156e9b56058SMatthew Dillon #define SWAPMAX(adj) \ 157e9b56058SMatthew Dillon ((int64_t)vm_swap_max * (vm_swapcache_maxswappct + (adj)) / 100) 158e9b56058SMatthew Dillon 159096e95c0SMatthew Dillon /* 160497524bfSMatthew Dillon * When shutting down the machine we want to stop swapcache operation 161497524bfSMatthew Dillon * immediately so swap is not accessed after devices have been shuttered. 162497524bfSMatthew Dillon */ 163497524bfSMatthew Dillon static void 164497524bfSMatthew Dillon shutdown_swapcache(void *arg __unused) 165497524bfSMatthew Dillon { 166497524bfSMatthew Dillon vm_swapcache_read_enable = 0; 167497524bfSMatthew Dillon vm_swapcache_data_enable = 0; 168497524bfSMatthew Dillon vm_swapcache_meta_enable = 0; 169497524bfSMatthew Dillon wakeup(&vm_swapcache_sleep); /* shortcut 5-second wait */ 170497524bfSMatthew Dillon } 171497524bfSMatthew Dillon 172497524bfSMatthew Dillon /* 173096e95c0SMatthew Dillon * vm_swapcached is the high level pageout daemon. 1748e7c4729SMatthew Dillon * 1758e7c4729SMatthew Dillon * No requirements. 176096e95c0SMatthew Dillon */ 177096e95c0SMatthew Dillon static void 178cd8ab232SMatthew Dillon vm_swapcached_thread(void) 179096e95c0SMatthew Dillon { 18000a3fdcaSMatthew Dillon enum { SWAPC_WRITING, SWAPC_CLEANING } state = SWAPC_WRITING; 1813ffc7051SMatthew Dillon enum { SWAPB_BURSTING, SWAPB_RECOVERING } burst = SWAPB_BURSTING; 18251c99c61SMatthew Dillon static struct vm_page page_marker[PQ_L2_SIZE]; 1839de48eadSMatthew Dillon static swmarker_t swmarker; 184fde6be6aSMatthew Dillon static struct vm_object_hash *swindex; 185027193ebSMatthew Dillon int q; 186096e95c0SMatthew Dillon 187096e95c0SMatthew Dillon /* 188096e95c0SMatthew Dillon * Thread setup 189096e95c0SMatthew Dillon */ 190096e95c0SMatthew Dillon curthread->td_flags |= TDF_SYSTHREAD; 191497524bfSMatthew Dillon EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, 192497524bfSMatthew Dillon swapcached_thread, SHUTDOWN_PRI_FIRST); 193497524bfSMatthew Dillon EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_swapcache, 194497524bfSMatthew Dillon NULL, SHUTDOWN_PRI_SECOND); 195096e95c0SMatthew Dillon 196096e95c0SMatthew Dillon /* 19700a3fdcaSMatthew Dillon * Initialize our marker for the inactive scan (SWAPC_WRITING) 198096e95c0SMatthew Dillon */ 19900a3fdcaSMatthew Dillon bzero(&page_marker, sizeof(page_marker)); 20051c99c61SMatthew Dillon for (q = 0; q < PQ_L2_SIZE; ++q) { 201bc0aa189SMatthew Dillon page_marker[q].flags = PG_FICTITIOUS | PG_MARKER; 202bc0aa189SMatthew Dillon page_marker[q].busy_count = PBUSY_LOCKED; 203027193ebSMatthew Dillon page_marker[q].queue = PQ_INACTIVE + q; 204027193ebSMatthew Dillon page_marker[q].pc = q; 205027193ebSMatthew Dillon page_marker[q].wire_count = 1; 206027193ebSMatthew Dillon vm_page_queues_spin_lock(PQ_INACTIVE + q); 207027193ebSMatthew Dillon TAILQ_INSERT_HEAD( 208027193ebSMatthew Dillon &vm_page_queues[PQ_INACTIVE + q].pl, 209027193ebSMatthew Dillon &page_marker[q], pageq); 210027193ebSMatthew Dillon vm_page_queues_spin_unlock(PQ_INACTIVE + q); 211027193ebSMatthew Dillon } 212b12defdcSMatthew Dillon 21364949baaSMatthew Dillon vm_swapcache_min_hysteresis = 1024; 21464949baaSMatthew Dillon vm_swapcache_hysteresis = vm_swapcache_min_hysteresis; 215b396bb03SMatthew Dillon vm_swapcache_wtrigger = -vm_swapcache_hysteresis; 216096e95c0SMatthew Dillon 21700a3fdcaSMatthew Dillon /* 21800a3fdcaSMatthew Dillon * Initialize our marker for the vm_object scan (SWAPC_CLEANING) 21900a3fdcaSMatthew Dillon */ 2207b00fbb4SMatthew Dillon bzero(&swmarker, sizeof(swmarker)); 2219de48eadSMatthew Dillon swmarker.dummy_obj.type = OBJT_MARKER; 222fde6be6aSMatthew Dillon swindex = &vm_object_hash[0]; 223fde6be6aSMatthew Dillon lwkt_gettoken(&swindex->token); 2245b329e62SMatthew Dillon TAILQ_INSERT_HEAD(&swindex->list, &swmarker.dummy_obj, object_entry); 225fde6be6aSMatthew Dillon lwkt_reltoken(&swindex->token); 226096e95c0SMatthew Dillon 227096e95c0SMatthew Dillon for (;;) { 22864949baaSMatthew Dillon int reached_end; 22964949baaSMatthew Dillon int scount; 23064949baaSMatthew Dillon int count; 23164949baaSMatthew Dillon 232096e95c0SMatthew Dillon /* 233497524bfSMatthew Dillon * Handle shutdown 234497524bfSMatthew Dillon */ 235497524bfSMatthew Dillon kproc_suspend_loop(); 236497524bfSMatthew Dillon 237497524bfSMatthew Dillon /* 2383da46bd7SMatthew Dillon * Check every 5 seconds when not enabled or if no swap 2393da46bd7SMatthew Dillon * is present. 240096e95c0SMatthew Dillon */ 2413da46bd7SMatthew Dillon if ((vm_swapcache_data_enable == 0 && 242c8ddd5d8SMatthew Dillon vm_swapcache_meta_enable == 0 && 243c8ddd5d8SMatthew Dillon vm_swap_cache_use <= SWAPMAX(0)) || 2443da46bd7SMatthew Dillon vm_swap_max == 0) { 245096e95c0SMatthew Dillon tsleep(&vm_swapcache_sleep, 0, "csleep", hz * 5); 246096e95c0SMatthew Dillon continue; 247096e95c0SMatthew Dillon } 248c504e38eSMatthew Dillon 249c504e38eSMatthew Dillon /* 2503da46bd7SMatthew Dillon * Polling rate when enabled is approximately 10 hz. 251c504e38eSMatthew Dillon */ 252c504e38eSMatthew Dillon tsleep(&vm_swapcache_sleep, 0, "csleep", hz / 10); 25300a3fdcaSMatthew Dillon 25400a3fdcaSMatthew Dillon /* 25500a3fdcaSMatthew Dillon * State hysteresis. Generate write activity up to 75% of 25600a3fdcaSMatthew Dillon * swap, then clean out swap assignments down to 70%, then 25700a3fdcaSMatthew Dillon * repeat. 25800a3fdcaSMatthew Dillon */ 25900a3fdcaSMatthew Dillon if (state == SWAPC_WRITING) { 260e9b56058SMatthew Dillon if (vm_swap_cache_use > SWAPMAX(0)) 26100a3fdcaSMatthew Dillon state = SWAPC_CLEANING; 26200a3fdcaSMatthew Dillon } else { 26308fb7a9dSMatthew Dillon if (vm_swap_cache_use < SWAPMAX(-10)) 26400a3fdcaSMatthew Dillon state = SWAPC_WRITING; 26500a3fdcaSMatthew Dillon } 26600a3fdcaSMatthew Dillon 26700a3fdcaSMatthew Dillon /* 26800a3fdcaSMatthew Dillon * We are allowed to continue accumulating burst value 2693ffc7051SMatthew Dillon * in either state. Allow the user to set curburst > maxburst 2703ffc7051SMatthew Dillon * for the initial load-in. 27100a3fdcaSMatthew Dillon */ 2723ffc7051SMatthew Dillon if (vm_swapcache_curburst < vm_swapcache_maxburst) { 273c504e38eSMatthew Dillon vm_swapcache_curburst += vm_swapcache_accrate / 10; 274c504e38eSMatthew Dillon if (vm_swapcache_curburst > vm_swapcache_maxburst) 275c504e38eSMatthew Dillon vm_swapcache_curburst = vm_swapcache_maxburst; 2763ffc7051SMatthew Dillon } 277c504e38eSMatthew Dillon 278c504e38eSMatthew Dillon /* 27900a3fdcaSMatthew Dillon * We don't want to nickle-and-dime the scan as that will 28000a3fdcaSMatthew Dillon * create unnecessary fragmentation. The minimum burst 28100a3fdcaSMatthew Dillon * is one-seconds worth of accumulation. 282c504e38eSMatthew Dillon */ 28364949baaSMatthew Dillon if (state != SWAPC_WRITING) { 2847b00fbb4SMatthew Dillon vm_swapcache_cleaning(&swmarker, &swindex); 28564949baaSMatthew Dillon continue; 28664949baaSMatthew Dillon } 28764949baaSMatthew Dillon if (vm_swapcache_curburst < vm_swapcache_accrate) 28864949baaSMatthew Dillon continue; 28964949baaSMatthew Dillon 29064949baaSMatthew Dillon reached_end = 0; 29164949baaSMatthew Dillon count = vm_swapcache_maxlaunder / PQ_L2_SIZE + 2; 29264949baaSMatthew Dillon scount = vm_swapcache_maxscan / PQ_L2_SIZE + 2; 29364949baaSMatthew Dillon 2943ffc7051SMatthew Dillon if (burst == SWAPB_BURSTING) { 29564949baaSMatthew Dillon if (vm_swapcache_writing_heuristic()) { 29651c99c61SMatthew Dillon for (q = 0; q < PQ_L2_SIZE; ++q) { 29764949baaSMatthew Dillon reached_end += 298027193ebSMatthew Dillon vm_swapcache_writing( 29964949baaSMatthew Dillon &page_marker[q], 30064949baaSMatthew Dillon count, 30164949baaSMatthew Dillon scount); 30264949baaSMatthew Dillon } 303027193ebSMatthew Dillon } 3043ffc7051SMatthew Dillon if (vm_swapcache_curburst <= 0) 3053ffc7051SMatthew Dillon burst = SWAPB_RECOVERING; 30664949baaSMatthew Dillon } else if (vm_swapcache_curburst > vm_swapcache_minburst) { 30764949baaSMatthew Dillon if (vm_swapcache_writing_heuristic()) { 30851c99c61SMatthew Dillon for (q = 0; q < PQ_L2_SIZE; ++q) { 30964949baaSMatthew Dillon reached_end += 310027193ebSMatthew Dillon vm_swapcache_writing( 31164949baaSMatthew Dillon &page_marker[q], 31264949baaSMatthew Dillon count, 31364949baaSMatthew Dillon scount); 31464949baaSMatthew Dillon } 315027193ebSMatthew Dillon } 3163ffc7051SMatthew Dillon burst = SWAPB_BURSTING; 3173ffc7051SMatthew Dillon } 31864949baaSMatthew Dillon if (reached_end == PQ_L2_SIZE) { 319b396bb03SMatthew Dillon vm_swapcache_wtrigger = -vm_swapcache_hysteresis; 32000a3fdcaSMatthew Dillon } 32100a3fdcaSMatthew Dillon } 322eccc8ca1SMatthew Dillon 323eccc8ca1SMatthew Dillon /* 324eccc8ca1SMatthew Dillon * Cleanup (NOT REACHED) 325eccc8ca1SMatthew Dillon */ 32651c99c61SMatthew Dillon for (q = 0; q < PQ_L2_SIZE; ++q) { 327027193ebSMatthew Dillon vm_page_queues_spin_lock(PQ_INACTIVE + q); 328027193ebSMatthew Dillon TAILQ_REMOVE( 329027193ebSMatthew Dillon &vm_page_queues[PQ_INACTIVE + q].pl, 330027193ebSMatthew Dillon &page_marker[q], pageq); 331027193ebSMatthew Dillon vm_page_queues_spin_unlock(PQ_INACTIVE + q); 332027193ebSMatthew Dillon } 333eccc8ca1SMatthew Dillon 334fde6be6aSMatthew Dillon lwkt_gettoken(&swindex->token); 3355b329e62SMatthew Dillon TAILQ_REMOVE(&swindex->list, &swmarker.dummy_obj, object_entry); 336fde6be6aSMatthew Dillon lwkt_reltoken(&swindex->token); 33700a3fdcaSMatthew Dillon } 338096e95c0SMatthew Dillon 339cd8ab232SMatthew Dillon static struct kproc_desc swpc_kp = { 340cd8ab232SMatthew Dillon "swapcached", 341cd8ab232SMatthew Dillon vm_swapcached_thread, 342cd8ab232SMatthew Dillon &swapcached_thread 343cd8ab232SMatthew Dillon }; 344f3f3eadbSSascha Wildner SYSINIT(swapcached, SI_SUB_KTHREAD_PAGE, SI_ORDER_SECOND, kproc_start, &swpc_kp); 345cd8ab232SMatthew Dillon 346096e95c0SMatthew Dillon /* 347fdc53cc7SMatthew Dillon * Deal with an overflow of the heuristic counter or if the user 348fdc53cc7SMatthew Dillon * manually changes the hysteresis. 349fdc53cc7SMatthew Dillon * 350e527fb6bSMatthew Dillon * Try to avoid small incremental pageouts by waiting for enough 351e527fb6bSMatthew Dillon * pages to buildup in the inactive queue to hopefully get a good 352e527fb6bSMatthew Dillon * burst in. This heuristic is bumped by the VM system and reset 353e527fb6bSMatthew Dillon * when our scan hits the end of the queue. 35464949baaSMatthew Dillon * 35564949baaSMatthew Dillon * Return TRUE if we need to take a writing pass. 356e527fb6bSMatthew Dillon */ 35764949baaSMatthew Dillon static int 35864949baaSMatthew Dillon vm_swapcache_writing_heuristic(void) 35964949baaSMatthew Dillon { 36064949baaSMatthew Dillon int hyst; 361b396bb03SMatthew Dillon int q; 362b396bb03SMatthew Dillon long adds; 36364949baaSMatthew Dillon 36464949baaSMatthew Dillon hyst = vmstats.v_inactive_count / 4; 36564949baaSMatthew Dillon if (hyst < vm_swapcache_min_hysteresis) 36664949baaSMatthew Dillon hyst = vm_swapcache_min_hysteresis; 36764949baaSMatthew Dillon cpu_ccfence(); 36864949baaSMatthew Dillon vm_swapcache_hysteresis = hyst; 36964949baaSMatthew Dillon 370b396bb03SMatthew Dillon adds = 0; 371b396bb03SMatthew Dillon for (q = PQ_INACTIVE; q < PQ_INACTIVE + PQ_L2_SIZE; ++q) { 372b396bb03SMatthew Dillon adds += atomic_swap_long(&vm_page_queues[q].adds, 0); 373b396bb03SMatthew Dillon } 374b396bb03SMatthew Dillon vm_swapcache_wtrigger += adds; 375b396bb03SMatthew Dillon if (vm_swapcache_wtrigger < -hyst) 376b396bb03SMatthew Dillon vm_swapcache_wtrigger = -hyst; 377b396bb03SMatthew Dillon return (vm_swapcache_wtrigger >= 0); 37864949baaSMatthew Dillon } 37964949baaSMatthew Dillon 38064949baaSMatthew Dillon /* 38164949baaSMatthew Dillon * Take a writing pass on one of the inactive queues, return non-zero if 38264949baaSMatthew Dillon * we hit the end of the queue. 38364949baaSMatthew Dillon */ 38464949baaSMatthew Dillon static int 38564949baaSMatthew Dillon vm_swapcache_writing(vm_page_t marker, int count, int scount) 38664949baaSMatthew Dillon { 38764949baaSMatthew Dillon vm_object_t object; 38864949baaSMatthew Dillon struct vnode *vp; 38964949baaSMatthew Dillon vm_page_t m; 39064949baaSMatthew Dillon int isblkdev; 391e527fb6bSMatthew Dillon 392e527fb6bSMatthew Dillon /* 393096e95c0SMatthew Dillon * Scan the inactive queue from our marker to locate 394096e95c0SMatthew Dillon * suitable pages to push to the swap cache. 395096e95c0SMatthew Dillon * 396096e95c0SMatthew Dillon * We are looking for clean vnode-backed pages. 397096e95c0SMatthew Dillon */ 398027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 3990bf81261SMatthew Dillon while ((m = TAILQ_NEXT(marker, pageq)) != NULL && 4000bf81261SMatthew Dillon count > 0 && scount-- > 0) { 401027193ebSMatthew Dillon KKASSERT(m->queue == marker->queue); 402b12defdcSMatthew Dillon 4031de864f0SMatthew Dillon /* 4041de864f0SMatthew Dillon * Stop using swap if paniced, dumping, or dumped. 4051de864f0SMatthew Dillon * Don't try to write if our curburst has been exhausted. 4061de864f0SMatthew Dillon */ 4071de864f0SMatthew Dillon if (panicstr || dumping) 4081de864f0SMatthew Dillon break; 409b12defdcSMatthew Dillon if (vm_swapcache_curburst < 0) 410b12defdcSMatthew Dillon break; 4111de864f0SMatthew Dillon 4121de864f0SMatthew Dillon /* 4131de864f0SMatthew Dillon * Move marker 4141de864f0SMatthew Dillon */ 415027193ebSMatthew Dillon TAILQ_REMOVE( 416027193ebSMatthew Dillon &vm_page_queues[marker->queue].pl, marker, pageq); 417027193ebSMatthew Dillon TAILQ_INSERT_AFTER( 418027193ebSMatthew Dillon &vm_page_queues[marker->queue].pl, m, marker, pageq); 419f5f6d247SMatthew Dillon 420f5f6d247SMatthew Dillon /* 421f5f6d247SMatthew Dillon * Ignore markers and ignore pages that already have a swap 422f5f6d247SMatthew Dillon * assignment. 423f5f6d247SMatthew Dillon */ 4240bf81261SMatthew Dillon if (m->flags & (PG_MARKER | PG_SWAPPED)) 425096e95c0SMatthew Dillon continue; 426b12defdcSMatthew Dillon if (vm_page_busy_try(m, TRUE)) 427096e95c0SMatthew Dillon continue; 428027193ebSMatthew Dillon vm_page_queues_spin_unlock(marker->queue); 429b12defdcSMatthew Dillon 430b12defdcSMatthew Dillon if ((object = m->object) == NULL) { 431b12defdcSMatthew Dillon vm_page_wakeup(m); 432027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 433b12defdcSMatthew Dillon continue; 434b12defdcSMatthew Dillon } 435b12defdcSMatthew Dillon vm_object_hold(object); 436b12defdcSMatthew Dillon if (m->object != object) { 437b12defdcSMatthew Dillon vm_object_drop(object); 438b12defdcSMatthew Dillon vm_page_wakeup(m); 439027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 440b12defdcSMatthew Dillon continue; 441b12defdcSMatthew Dillon } 442b12defdcSMatthew Dillon if (vm_swapcache_test(m)) { 443b12defdcSMatthew Dillon vm_object_drop(object); 444b12defdcSMatthew Dillon vm_page_wakeup(m); 445027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 446b12defdcSMatthew Dillon continue; 447b12defdcSMatthew Dillon } 448b12defdcSMatthew Dillon 449c504e38eSMatthew Dillon vp = object->handle; 450b12defdcSMatthew Dillon if (vp == NULL) { 451b12defdcSMatthew Dillon vm_object_drop(object); 452b12defdcSMatthew Dillon vm_page_wakeup(m); 453027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 454c504e38eSMatthew Dillon continue; 455b12defdcSMatthew Dillon } 456d3070b8dSMatthew Dillon 457c504e38eSMatthew Dillon switch(vp->v_type) { 458c504e38eSMatthew Dillon case VREG: 459e9b56058SMatthew Dillon /* 460bfa86281SMatthew Dillon * PG_NOTMETA generically means 'don't swapcache this', 461bfa86281SMatthew Dillon * and HAMMER will set this for regular data buffers 462bfa86281SMatthew Dillon * (and leave it unset for meta-data buffers) as 463bfa86281SMatthew Dillon * appropriate when double buffering is enabled. 464bfa86281SMatthew Dillon */ 465b12defdcSMatthew Dillon if (m->flags & PG_NOTMETA) { 466b12defdcSMatthew Dillon vm_object_drop(object); 467b12defdcSMatthew Dillon vm_page_wakeup(m); 468027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 469bfa86281SMatthew Dillon continue; 470b12defdcSMatthew Dillon } 471bfa86281SMatthew Dillon 472bfa86281SMatthew Dillon /* 473e9b56058SMatthew Dillon * If data_enable is 0 do not try to swapcache data. 474e9b56058SMatthew Dillon * If use_chflags is set then only swapcache data for 475e9b56058SMatthew Dillon * VSWAPCACHE marked vnodes, otherwise any vnode. 476e9b56058SMatthew Dillon */ 477e9b56058SMatthew Dillon if (vm_swapcache_data_enable == 0 || 478e9b56058SMatthew Dillon ((vp->v_flag & VSWAPCACHE) == 0 && 479e9b56058SMatthew Dillon vm_swapcache_use_chflags)) { 480b12defdcSMatthew Dillon vm_object_drop(object); 481b12defdcSMatthew Dillon vm_page_wakeup(m); 482027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 483c504e38eSMatthew Dillon continue; 484e9b56058SMatthew Dillon } 485d3070b8dSMatthew Dillon if (vm_swapcache_maxfilesize && 486d3070b8dSMatthew Dillon object->size > 487d3070b8dSMatthew Dillon (vm_swapcache_maxfilesize >> PAGE_SHIFT)) { 488b12defdcSMatthew Dillon vm_object_drop(object); 489b12defdcSMatthew Dillon vm_page_wakeup(m); 490027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 491d3070b8dSMatthew Dillon continue; 492d3070b8dSMatthew Dillon } 493aabd5ce8SMatthew Dillon isblkdev = 0; 494c504e38eSMatthew Dillon break; 495c504e38eSMatthew Dillon case VCHR: 496aabd5ce8SMatthew Dillon /* 497bfa86281SMatthew Dillon * PG_NOTMETA generically means 'don't swapcache this', 498bfa86281SMatthew Dillon * and HAMMER will set this for regular data buffers 499bfa86281SMatthew Dillon * (and leave it unset for meta-data buffers) as 500bfa86281SMatthew Dillon * appropriate when double buffering is enabled. 501aabd5ce8SMatthew Dillon */ 502b12defdcSMatthew Dillon if (m->flags & PG_NOTMETA) { 503b12defdcSMatthew Dillon vm_object_drop(object); 504b12defdcSMatthew Dillon vm_page_wakeup(m); 505027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 506aabd5ce8SMatthew Dillon continue; 507b12defdcSMatthew Dillon } 508b12defdcSMatthew Dillon if (vm_swapcache_meta_enable == 0) { 509b12defdcSMatthew Dillon vm_object_drop(object); 510b12defdcSMatthew Dillon vm_page_wakeup(m); 511027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 512c504e38eSMatthew Dillon continue; 513b12defdcSMatthew Dillon } 514aabd5ce8SMatthew Dillon isblkdev = 1; 515c504e38eSMatthew Dillon break; 516c504e38eSMatthew Dillon default: 517b12defdcSMatthew Dillon vm_object_drop(object); 518b12defdcSMatthew Dillon vm_page_wakeup(m); 519027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 520c504e38eSMatthew Dillon continue; 521c504e38eSMatthew Dillon } 522096e95c0SMatthew Dillon 523096e95c0SMatthew Dillon 524096e95c0SMatthew Dillon /* 5253ffc7051SMatthew Dillon * Assign swap and initiate I/O. 5263ffc7051SMatthew Dillon * 5273ffc7051SMatthew Dillon * (adjust for the --count which also occurs in the loop) 528096e95c0SMatthew Dillon */ 5290bf81261SMatthew Dillon count -= vm_swapcached_flush(m, isblkdev); 530096e95c0SMatthew Dillon 531096e95c0SMatthew Dillon /* 532096e95c0SMatthew Dillon * Setup for next loop using marker. 533096e95c0SMatthew Dillon */ 534b12defdcSMatthew Dillon vm_object_drop(object); 535027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 536096e95c0SMatthew Dillon } 5371e5196f0SMatthew Dillon 5381e5196f0SMatthew Dillon /* 539b12defdcSMatthew Dillon * The marker could wind up at the end, which is ok. If we hit the 540b12defdcSMatthew Dillon * end of the list adjust the heuristic. 5411e5196f0SMatthew Dillon * 5421e5196f0SMatthew Dillon * Earlier inactive pages that were dirty and become clean 5431e5196f0SMatthew Dillon * are typically moved to the end of PQ_INACTIVE by virtue 5441e5196f0SMatthew Dillon * of vfs_vmio_release() when they become unwired from the 5451e5196f0SMatthew Dillon * buffer cache. 5461e5196f0SMatthew Dillon */ 547027193ebSMatthew Dillon vm_page_queues_spin_unlock(marker->queue); 54864949baaSMatthew Dillon 54964949baaSMatthew Dillon /* 55064949baaSMatthew Dillon * m invalid but can be used to test for NULL 55164949baaSMatthew Dillon */ 55264949baaSMatthew Dillon return (m == NULL); 553096e95c0SMatthew Dillon } 554096e95c0SMatthew Dillon 555096e95c0SMatthew Dillon /* 556b12defdcSMatthew Dillon * Flush the specified page using the swap_pager. The page 557b12defdcSMatthew Dillon * must be busied by the caller and its disposition will become 558b12defdcSMatthew Dillon * the responsibility of this function. 5593ffc7051SMatthew Dillon * 5603ffc7051SMatthew Dillon * Try to collect surrounding pages, including pages which may 5613ffc7051SMatthew Dillon * have already been assigned swap. Try to cluster within a 5623ffc7051SMatthew Dillon * contiguous aligned SMAP_META_PAGES (typ 16 x PAGE_SIZE) block 5633ffc7051SMatthew Dillon * to match what swap_pager_putpages() can do. 5643ffc7051SMatthew Dillon * 5653ffc7051SMatthew Dillon * We also want to try to match against the buffer cache blocksize 5663ffc7051SMatthew Dillon * but we don't really know what it is here. Since the buffer cache 5673ffc7051SMatthew Dillon * wires and unwires pages in groups the fact that we skip wired pages 5683ffc7051SMatthew Dillon * should be sufficient. 5693ffc7051SMatthew Dillon * 5703ffc7051SMatthew Dillon * Returns a count of pages we might have flushed (minimum 1) 571096e95c0SMatthew Dillon */ 572096e95c0SMatthew Dillon static 5733ffc7051SMatthew Dillon int 574aabd5ce8SMatthew Dillon vm_swapcached_flush(vm_page_t m, int isblkdev) 575096e95c0SMatthew Dillon { 576096e95c0SMatthew Dillon vm_object_t object; 5773ffc7051SMatthew Dillon vm_page_t marray[SWAP_META_PAGES]; 5783ffc7051SMatthew Dillon vm_pindex_t basei; 5793ffc7051SMatthew Dillon int rtvals[SWAP_META_PAGES]; 5803ffc7051SMatthew Dillon int x; 5813ffc7051SMatthew Dillon int i; 5823ffc7051SMatthew Dillon int j; 5833ffc7051SMatthew Dillon int count; 584b12defdcSMatthew Dillon int error; 585096e95c0SMatthew Dillon 586096e95c0SMatthew Dillon vm_page_io_start(m); 587096e95c0SMatthew Dillon vm_page_protect(m, VM_PROT_READ); 588096e95c0SMatthew Dillon object = m->object; 589b12defdcSMatthew Dillon vm_object_hold(object); 590096e95c0SMatthew Dillon 5913ffc7051SMatthew Dillon /* 5923ffc7051SMatthew Dillon * Try to cluster around (m), keeping in mind that the swap pager 5933ffc7051SMatthew Dillon * can only do SMAP_META_PAGES worth of continguous write. 5943ffc7051SMatthew Dillon */ 5953ffc7051SMatthew Dillon x = (int)m->pindex & SWAP_META_MASK; 5963ffc7051SMatthew Dillon marray[x] = m; 5973ffc7051SMatthew Dillon basei = m->pindex; 598b12defdcSMatthew Dillon vm_page_wakeup(m); 5993ffc7051SMatthew Dillon 6003ffc7051SMatthew Dillon for (i = x - 1; i >= 0; --i) { 601b12defdcSMatthew Dillon m = vm_page_lookup_busy_try(object, basei - x + i, 602b12defdcSMatthew Dillon TRUE, &error); 603b12defdcSMatthew Dillon if (error || m == NULL) 6043ffc7051SMatthew Dillon break; 605b12defdcSMatthew Dillon if (vm_swapcache_test(m)) { 606b12defdcSMatthew Dillon vm_page_wakeup(m); 6073ffc7051SMatthew Dillon break; 608b12defdcSMatthew Dillon } 609b12defdcSMatthew Dillon if (isblkdev && (m->flags & PG_NOTMETA)) { 610b12defdcSMatthew Dillon vm_page_wakeup(m); 611aabd5ce8SMatthew Dillon break; 612b12defdcSMatthew Dillon } 6133ffc7051SMatthew Dillon vm_page_io_start(m); 6143ffc7051SMatthew Dillon vm_page_protect(m, VM_PROT_READ); 6153ffc7051SMatthew Dillon if (m->queue - m->pc == PQ_CACHE) { 6163ffc7051SMatthew Dillon vm_page_unqueue_nowakeup(m); 6173ffc7051SMatthew Dillon vm_page_deactivate(m); 6183ffc7051SMatthew Dillon } 6193ffc7051SMatthew Dillon marray[i] = m; 620b12defdcSMatthew Dillon vm_page_wakeup(m); 6213ffc7051SMatthew Dillon } 6223ffc7051SMatthew Dillon ++i; 6233ffc7051SMatthew Dillon 6243ffc7051SMatthew Dillon for (j = x + 1; j < SWAP_META_PAGES; ++j) { 625b12defdcSMatthew Dillon m = vm_page_lookup_busy_try(object, basei - x + j, 626b12defdcSMatthew Dillon TRUE, &error); 627b12defdcSMatthew Dillon if (error || m == NULL) 6283ffc7051SMatthew Dillon break; 629b12defdcSMatthew Dillon if (vm_swapcache_test(m)) { 630b12defdcSMatthew Dillon vm_page_wakeup(m); 6313ffc7051SMatthew Dillon break; 632b12defdcSMatthew Dillon } 633b12defdcSMatthew Dillon if (isblkdev && (m->flags & PG_NOTMETA)) { 634b12defdcSMatthew Dillon vm_page_wakeup(m); 635aabd5ce8SMatthew Dillon break; 636b12defdcSMatthew Dillon } 6373ffc7051SMatthew Dillon vm_page_io_start(m); 6383ffc7051SMatthew Dillon vm_page_protect(m, VM_PROT_READ); 6393ffc7051SMatthew Dillon if (m->queue - m->pc == PQ_CACHE) { 6403ffc7051SMatthew Dillon vm_page_unqueue_nowakeup(m); 6413ffc7051SMatthew Dillon vm_page_deactivate(m); 6423ffc7051SMatthew Dillon } 6433ffc7051SMatthew Dillon marray[j] = m; 644b12defdcSMatthew Dillon vm_page_wakeup(m); 6453ffc7051SMatthew Dillon } 6463ffc7051SMatthew Dillon 6473ffc7051SMatthew Dillon count = j - i; 6483ffc7051SMatthew Dillon vm_object_pip_add(object, count); 6493ffc7051SMatthew Dillon swap_pager_putpages(object, marray + i, count, FALSE, rtvals + i); 6503ffc7051SMatthew Dillon vm_swapcache_write_count += count * PAGE_SIZE; 6513ffc7051SMatthew Dillon vm_swapcache_curburst -= count * PAGE_SIZE; 6523ffc7051SMatthew Dillon 6533ffc7051SMatthew Dillon while (i < j) { 6543ffc7051SMatthew Dillon if (rtvals[i] != VM_PAGER_PEND) { 655b12defdcSMatthew Dillon vm_page_busy_wait(marray[i], FALSE, "swppgfd"); 6563ffc7051SMatthew Dillon vm_page_io_finish(marray[i]); 657b12defdcSMatthew Dillon vm_page_wakeup(marray[i]); 658096e95c0SMatthew Dillon vm_object_pip_wakeup(object); 659096e95c0SMatthew Dillon } 6603ffc7051SMatthew Dillon ++i; 6613ffc7051SMatthew Dillon } 662b12defdcSMatthew Dillon vm_object_drop(object); 6633ffc7051SMatthew Dillon return(count); 664096e95c0SMatthew Dillon } 66500a3fdcaSMatthew Dillon 6663ffc7051SMatthew Dillon /* 6673ffc7051SMatthew Dillon * Test whether a VM page is suitable for writing to the swapcache. 6683ffc7051SMatthew Dillon * Does not test m->queue, PG_MARKER, or PG_SWAPPED. 6693ffc7051SMatthew Dillon * 6703ffc7051SMatthew Dillon * Returns 0 on success, 1 on failure 6713ffc7051SMatthew Dillon */ 6723ffc7051SMatthew Dillon static int 6733ffc7051SMatthew Dillon vm_swapcache_test(vm_page_t m) 6743ffc7051SMatthew Dillon { 6753ffc7051SMatthew Dillon vm_object_t object; 6763ffc7051SMatthew Dillon 677*831a8507SMatthew Dillon if (m->flags & (PG_UNQUEUED | PG_FICTITIOUS)) 6783ffc7051SMatthew Dillon return(1); 679b12defdcSMatthew Dillon if (m->hold_count || m->wire_count) 6803ffc7051SMatthew Dillon return(1); 6813ffc7051SMatthew Dillon if (m->valid != VM_PAGE_BITS_ALL) 6823ffc7051SMatthew Dillon return(1); 6833ffc7051SMatthew Dillon if (m->dirty & m->valid) 6843ffc7051SMatthew Dillon return(1); 6853ffc7051SMatthew Dillon if ((object = m->object) == NULL) 6863ffc7051SMatthew Dillon return(1); 6873ffc7051SMatthew Dillon if (object->type != OBJT_VNODE || 6883ffc7051SMatthew Dillon (object->flags & OBJ_DEAD)) { 6893ffc7051SMatthew Dillon return(1); 6903ffc7051SMatthew Dillon } 6913ffc7051SMatthew Dillon vm_page_test_dirty(m); 6923ffc7051SMatthew Dillon if (m->dirty & m->valid) 6933ffc7051SMatthew Dillon return(1); 6943ffc7051SMatthew Dillon return(0); 6953ffc7051SMatthew Dillon } 6963ffc7051SMatthew Dillon 6973ffc7051SMatthew Dillon /* 698f5f6d247SMatthew Dillon * Cleaning pass. 699f5f6d247SMatthew Dillon * 700f5f6d247SMatthew Dillon * We clean whole objects up to 16MB 7013ffc7051SMatthew Dillon */ 70200a3fdcaSMatthew Dillon static 70300a3fdcaSMatthew Dillon void 7049de48eadSMatthew Dillon vm_swapcache_cleaning(swmarker_t *marker, struct vm_object_hash **swindexp) 70500a3fdcaSMatthew Dillon { 70600a3fdcaSMatthew Dillon vm_object_t object; 70700a3fdcaSMatthew Dillon struct vnode *vp; 70800a3fdcaSMatthew Dillon int count; 7090bf81261SMatthew Dillon int scount; 71000a3fdcaSMatthew Dillon int n; 711eea5ad68SMatthew Dillon int didmove; 71200a3fdcaSMatthew Dillon 71300a3fdcaSMatthew Dillon count = vm_swapcache_maxlaunder; 7140bf81261SMatthew Dillon scount = vm_swapcache_maxscan; 71500a3fdcaSMatthew Dillon 71600a3fdcaSMatthew Dillon /* 71700a3fdcaSMatthew Dillon * Look for vnode objects 71800a3fdcaSMatthew Dillon */ 719fde6be6aSMatthew Dillon lwkt_gettoken(&(*swindexp)->token); 7202de4f77eSMatthew Dillon 721eea5ad68SMatthew Dillon didmove = 0; 722b2286ce7SMatthew Dillon outerloop: 7235b329e62SMatthew Dillon while ((object = TAILQ_NEXT(&marker->dummy_obj, 7245b329e62SMatthew Dillon object_entry)) != NULL) { 7252f2d9e58SVenkatesh Srinivas /* 726f5f6d247SMatthew Dillon * We have to skip markers. We cannot hold/drop marker 727f5f6d247SMatthew Dillon * objects! 7282f2d9e58SVenkatesh Srinivas */ 729f5f6d247SMatthew Dillon if (object->type == OBJT_MARKER) { 7307b00fbb4SMatthew Dillon vm_swapcache_movemarker(marker, *swindexp, object); 731eea5ad68SMatthew Dillon didmove = 1; 73200a3fdcaSMatthew Dillon continue; 7332f2d9e58SVenkatesh Srinivas } 73400a3fdcaSMatthew Dillon 73500a3fdcaSMatthew Dillon /* 736f5f6d247SMatthew Dillon * Safety, or in case there are millions of VM objects 737f5f6d247SMatthew Dillon * without swapcache backing. 73800a3fdcaSMatthew Dillon */ 7390bf81261SMatthew Dillon if (--scount <= 0) 7407b00fbb4SMatthew Dillon goto breakout; 74100a3fdcaSMatthew Dillon 74200a3fdcaSMatthew Dillon /* 743f5f6d247SMatthew Dillon * We must hold the object before potentially yielding. 74400a3fdcaSMatthew Dillon */ 745f5f6d247SMatthew Dillon vm_object_hold(object); 746f5f6d247SMatthew Dillon lwkt_yield(); 747f5f6d247SMatthew Dillon 748f5f6d247SMatthew Dillon /* 749f5f6d247SMatthew Dillon * Only operate on live VNODE objects that are either 750f5f6d247SMatthew Dillon * VREG or VCHR (VCHR for meta-data). 751f5f6d247SMatthew Dillon */ 752f5f6d247SMatthew Dillon if ((object->type != OBJT_VNODE) || 753f5f6d247SMatthew Dillon ((object->flags & OBJ_DEAD) || 754f5f6d247SMatthew Dillon object->swblock_count == 0) || 755f5f6d247SMatthew Dillon ((vp = object->handle) == NULL) || 756f5f6d247SMatthew Dillon (vp->v_type != VREG && vp->v_type != VCHR)) { 757f5f6d247SMatthew Dillon vm_object_drop(object); 758f5f6d247SMatthew Dillon /* object may be invalid now */ 7597b00fbb4SMatthew Dillon vm_swapcache_movemarker(marker, *swindexp, object); 760eea5ad68SMatthew Dillon didmove = 1; 761f5f6d247SMatthew Dillon continue; 762f5f6d247SMatthew Dillon } 763f5f6d247SMatthew Dillon 764f5f6d247SMatthew Dillon /* 765f5f6d247SMatthew Dillon * Reset the object pindex stored in the marker if the 766f5f6d247SMatthew Dillon * working object has changed. 767f5f6d247SMatthew Dillon */ 7689de48eadSMatthew Dillon if (marker->save_obj != object || didmove) { 7699de48eadSMatthew Dillon marker->dummy_obj.size = 0; 7709de48eadSMatthew Dillon marker->save_off = 0; 7719de48eadSMatthew Dillon marker->save_obj = object; 772eea5ad68SMatthew Dillon didmove = 0; 773f5f6d247SMatthew Dillon } 77400a3fdcaSMatthew Dillon 77500a3fdcaSMatthew Dillon /* 77600a3fdcaSMatthew Dillon * Look for swblocks starting at our iterator. 77700a3fdcaSMatthew Dillon * 77800a3fdcaSMatthew Dillon * The swap_pager_condfree() function attempts to free 77900a3fdcaSMatthew Dillon * swap space starting at the specified index. The index 78000a3fdcaSMatthew Dillon * will be updated on return. The function will return 78100a3fdcaSMatthew Dillon * a scan factor (NOT the number of blocks freed). 78200a3fdcaSMatthew Dillon * 78300a3fdcaSMatthew Dillon * If it must cut its scan of the object short due to an 78400a3fdcaSMatthew Dillon * excessive number of swblocks, or is able to free the 78500a3fdcaSMatthew Dillon * requested number of blocks, it will return n >= count 78600a3fdcaSMatthew Dillon * and we break and pick it back up on a future attempt. 787f5f6d247SMatthew Dillon * 788f5f6d247SMatthew Dillon * Scan the object linearly and try to batch large sets of 789f5f6d247SMatthew Dillon * blocks that are likely to clean out entire swap radix 790f5f6d247SMatthew Dillon * tree leafs. 79100a3fdcaSMatthew Dillon */ 792739be60bSMatthew Dillon lwkt_token_swap(); 793fde6be6aSMatthew Dillon lwkt_reltoken(&(*swindexp)->token); 79427b6ee03SMatthew Dillon 7959de48eadSMatthew Dillon n = swap_pager_condfree(object, &marker->dummy_obj.size, 796f5f6d247SMatthew Dillon (count + SWAP_META_MASK) & ~SWAP_META_MASK); 7972f2d9e58SVenkatesh Srinivas 798f5f6d247SMatthew Dillon vm_object_drop(object); /* object may be invalid now */ 799fde6be6aSMatthew Dillon lwkt_gettoken(&(*swindexp)->token); 8002f2d9e58SVenkatesh Srinivas 80100a3fdcaSMatthew Dillon /* 802f5f6d247SMatthew Dillon * If we have exhausted the object or deleted our per-pass 803f5f6d247SMatthew Dillon * page limit then move us to the next object. Note that 8045b329e62SMatthew Dillon * the current object may no longer be on the vm_object_entry. 80500a3fdcaSMatthew Dillon */ 806f5f6d247SMatthew Dillon if (n <= 0 || 8079de48eadSMatthew Dillon marker->save_off > vm_swapcache_cleanperobj) { 8087b00fbb4SMatthew Dillon vm_swapcache_movemarker(marker, *swindexp, object); 809eea5ad68SMatthew Dillon didmove = 1; 81000a3fdcaSMatthew Dillon } 81100a3fdcaSMatthew Dillon 81200a3fdcaSMatthew Dillon /* 813f5f6d247SMatthew Dillon * If we have exhausted our max-launder stop for now. 81400a3fdcaSMatthew Dillon */ 815f5f6d247SMatthew Dillon count -= n; 8169de48eadSMatthew Dillon marker->save_off += n * PAGE_SIZE; 817f5f6d247SMatthew Dillon if (count < 0) 8187b00fbb4SMatthew Dillon goto breakout; 819f5f6d247SMatthew Dillon } 8207a175765SMatthew Dillon 8217a175765SMatthew Dillon /* 8225b329e62SMatthew Dillon * Iterate vm_object_hash[] hash table 8237a175765SMatthew Dillon */ 8245b329e62SMatthew Dillon TAILQ_REMOVE(&(*swindexp)->list, &marker->dummy_obj, object_entry); 825fde6be6aSMatthew Dillon lwkt_reltoken(&(*swindexp)->token); 826fde6be6aSMatthew Dillon if (++*swindexp >= &vm_object_hash[VMOBJ_HSIZE]) 827fde6be6aSMatthew Dillon *swindexp = &vm_object_hash[0]; 828fde6be6aSMatthew Dillon lwkt_gettoken(&(*swindexp)->token); 8295b329e62SMatthew Dillon TAILQ_INSERT_HEAD(&(*swindexp)->list, &marker->dummy_obj, object_entry); 8307a175765SMatthew Dillon 831fde6be6aSMatthew Dillon if (*swindexp != &vm_object_hash[0]) 8327b00fbb4SMatthew Dillon goto outerloop; 8337b00fbb4SMatthew Dillon 8347b00fbb4SMatthew Dillon breakout: 835fde6be6aSMatthew Dillon lwkt_reltoken(&(*swindexp)->token); 83600a3fdcaSMatthew Dillon } 837f5f6d247SMatthew Dillon 838f5f6d247SMatthew Dillon /* 839f5f6d247SMatthew Dillon * Move the marker past the current object. Object can be stale, but we 840f5f6d247SMatthew Dillon * still need it to determine if the marker has to be moved. If the object 841f5f6d247SMatthew Dillon * is still the 'current object' (object after the marker), we hop-scotch 842f5f6d247SMatthew Dillon * the marker past it. 843f5f6d247SMatthew Dillon */ 844f5f6d247SMatthew Dillon static void 8459de48eadSMatthew Dillon vm_swapcache_movemarker(swmarker_t *marker, struct vm_object_hash *swindex, 846fde6be6aSMatthew Dillon vm_object_t object) 847f5f6d247SMatthew Dillon { 8485b329e62SMatthew Dillon if (TAILQ_NEXT(&marker->dummy_obj, object_entry) == object) { 8495b329e62SMatthew Dillon TAILQ_REMOVE(&swindex->list, &marker->dummy_obj, object_entry); 8509de48eadSMatthew Dillon TAILQ_INSERT_AFTER(&swindex->list, object, 8515b329e62SMatthew Dillon &marker->dummy_obj, object_entry); 852f5f6d247SMatthew Dillon } 853f5f6d247SMatthew Dillon } 854