1096e95c0SMatthew Dillon /* 28e7c4729SMatthew Dillon * (MPSAFE) 38e7c4729SMatthew Dillon * 4096e95c0SMatthew Dillon * Copyright (c) 2010 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 78096e95c0SMatthew Dillon #include <sys/thread2.h> 79b12defdcSMatthew Dillon #include <sys/spinlock2.h> 80096e95c0SMatthew Dillon #include <vm/vm_page2.h> 81096e95c0SMatthew Dillon 82096e95c0SMatthew Dillon /* the kernel process "vm_pageout"*/ 83aabd5ce8SMatthew Dillon static int vm_swapcached_flush (vm_page_t m, int isblkdev); 843ffc7051SMatthew Dillon static int vm_swapcache_test(vm_page_t m); 8564949baaSMatthew Dillon static int vm_swapcache_writing_heuristic(void); 8664949baaSMatthew Dillon static int vm_swapcache_writing(vm_page_t marker, int count, int scount); 87fde6be6aSMatthew Dillon static void vm_swapcache_cleaning(vm_object_t marker, 88fde6be6aSMatthew Dillon struct vm_object_hash **swindexp); 89fde6be6aSMatthew Dillon static void vm_swapcache_movemarker(vm_object_t marker, 90fde6be6aSMatthew Dillon struct vm_object_hash *swindex, vm_object_t object); 91096e95c0SMatthew Dillon struct thread *swapcached_thread; 92096e95c0SMatthew Dillon 93096e95c0SMatthew Dillon SYSCTL_NODE(_vm, OID_AUTO, swapcache, CTLFLAG_RW, NULL, NULL); 94096e95c0SMatthew Dillon 95c504e38eSMatthew Dillon int vm_swapcache_read_enable; 96e527fb6bSMatthew Dillon int vm_swapcache_inactive_heuristic; 97096e95c0SMatthew Dillon static int vm_swapcache_sleep; 9864949baaSMatthew Dillon static int vm_swapcache_maxscan = PQ_L2_SIZE * 8; 9964949baaSMatthew Dillon static int vm_swapcache_maxlaunder = PQ_L2_SIZE * 4; 100096e95c0SMatthew Dillon static int vm_swapcache_data_enable = 0; 101096e95c0SMatthew Dillon static int vm_swapcache_meta_enable = 0; 102e9b56058SMatthew Dillon static int vm_swapcache_maxswappct = 75; 103e527fb6bSMatthew Dillon static int vm_swapcache_hysteresis; 10464949baaSMatthew Dillon static int vm_swapcache_min_hysteresis; 105d4d9221dSMatthew Dillon int vm_swapcache_use_chflags = 0; /* require chflags cache */ 1063ffc7051SMatthew Dillon static int64_t vm_swapcache_minburst = 10000000LL; /* 10MB */ 1073ffc7051SMatthew Dillon static int64_t vm_swapcache_curburst = 4000000000LL; /* 4G after boot */ 1083ffc7051SMatthew Dillon static int64_t vm_swapcache_maxburst = 2000000000LL; /* 2G nominal max */ 1093ffc7051SMatthew Dillon static int64_t vm_swapcache_accrate = 100000LL; /* 100K/s */ 110096e95c0SMatthew Dillon static int64_t vm_swapcache_write_count; 1113ffc7051SMatthew Dillon static int64_t vm_swapcache_maxfilesize; 112f5f6d247SMatthew Dillon static int64_t vm_swapcache_cleanperobj = 16*1024*1024; 113096e95c0SMatthew Dillon 114096e95c0SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, maxlaunder, 115096e95c0SMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxlaunder, 0, ""); 1160bf81261SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, maxscan, 1170bf81261SMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxscan, 0, ""); 118c504e38eSMatthew Dillon 119096e95c0SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, data_enable, 120096e95c0SMatthew Dillon CTLFLAG_RW, &vm_swapcache_data_enable, 0, ""); 121096e95c0SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, meta_enable, 122096e95c0SMatthew Dillon CTLFLAG_RW, &vm_swapcache_meta_enable, 0, ""); 123c504e38eSMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, read_enable, 124c504e38eSMatthew Dillon CTLFLAG_RW, &vm_swapcache_read_enable, 0, ""); 125e9b56058SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, maxswappct, 126e9b56058SMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxswappct, 0, ""); 127e527fb6bSMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, hysteresis, 12864949baaSMatthew Dillon CTLFLAG_RD, &vm_swapcache_hysteresis, 0, ""); 12964949baaSMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, min_hysteresis, 13064949baaSMatthew Dillon CTLFLAG_RW, &vm_swapcache_min_hysteresis, 0, ""); 131e9b56058SMatthew Dillon SYSCTL_INT(_vm_swapcache, OID_AUTO, use_chflags, 132e9b56058SMatthew Dillon CTLFLAG_RW, &vm_swapcache_use_chflags, 0, ""); 133c504e38eSMatthew Dillon 1343ffc7051SMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, minburst, 1353ffc7051SMatthew Dillon CTLFLAG_RW, &vm_swapcache_minburst, 0, ""); 136c504e38eSMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, curburst, 137c504e38eSMatthew Dillon CTLFLAG_RW, &vm_swapcache_curburst, 0, ""); 138c504e38eSMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, maxburst, 139c504e38eSMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxburst, 0, ""); 1403ffc7051SMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, maxfilesize, 1413ffc7051SMatthew Dillon CTLFLAG_RW, &vm_swapcache_maxfilesize, 0, ""); 142c504e38eSMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, accrate, 143c504e38eSMatthew Dillon CTLFLAG_RW, &vm_swapcache_accrate, 0, ""); 144096e95c0SMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, write_count, 145096e95c0SMatthew Dillon CTLFLAG_RW, &vm_swapcache_write_count, 0, ""); 146f5f6d247SMatthew Dillon SYSCTL_QUAD(_vm_swapcache, OID_AUTO, cleanperobj, 147f5f6d247SMatthew Dillon CTLFLAG_RW, &vm_swapcache_cleanperobj, 0, ""); 148096e95c0SMatthew Dillon 149e9b56058SMatthew Dillon #define SWAPMAX(adj) \ 150e9b56058SMatthew Dillon ((int64_t)vm_swap_max * (vm_swapcache_maxswappct + (adj)) / 100) 151e9b56058SMatthew Dillon 152096e95c0SMatthew Dillon /* 153497524bfSMatthew Dillon * When shutting down the machine we want to stop swapcache operation 154497524bfSMatthew Dillon * immediately so swap is not accessed after devices have been shuttered. 155497524bfSMatthew Dillon */ 156497524bfSMatthew Dillon static void 157497524bfSMatthew Dillon shutdown_swapcache(void *arg __unused) 158497524bfSMatthew Dillon { 159497524bfSMatthew Dillon vm_swapcache_read_enable = 0; 160497524bfSMatthew Dillon vm_swapcache_data_enable = 0; 161497524bfSMatthew Dillon vm_swapcache_meta_enable = 0; 162497524bfSMatthew Dillon wakeup(&vm_swapcache_sleep); /* shortcut 5-second wait */ 163497524bfSMatthew Dillon } 164497524bfSMatthew Dillon 165497524bfSMatthew Dillon /* 166096e95c0SMatthew Dillon * vm_swapcached is the high level pageout daemon. 1678e7c4729SMatthew Dillon * 1688e7c4729SMatthew Dillon * No requirements. 169096e95c0SMatthew Dillon */ 170096e95c0SMatthew Dillon static void 171cd8ab232SMatthew Dillon vm_swapcached_thread(void) 172096e95c0SMatthew Dillon { 17300a3fdcaSMatthew Dillon enum { SWAPC_WRITING, SWAPC_CLEANING } state = SWAPC_WRITING; 1743ffc7051SMatthew Dillon enum { SWAPB_BURSTING, SWAPB_RECOVERING } burst = SWAPB_BURSTING; 17551c99c61SMatthew Dillon static struct vm_page page_marker[PQ_L2_SIZE]; 1767b00fbb4SMatthew Dillon static struct vm_object swmarker; 177fde6be6aSMatthew Dillon static struct vm_object_hash *swindex; 178027193ebSMatthew Dillon int q; 179096e95c0SMatthew Dillon 180096e95c0SMatthew Dillon /* 181096e95c0SMatthew Dillon * Thread setup 182096e95c0SMatthew Dillon */ 183096e95c0SMatthew Dillon curthread->td_flags |= TDF_SYSTHREAD; 184497524bfSMatthew Dillon EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, 185497524bfSMatthew Dillon swapcached_thread, SHUTDOWN_PRI_FIRST); 186497524bfSMatthew Dillon EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_swapcache, 187497524bfSMatthew Dillon NULL, SHUTDOWN_PRI_SECOND); 188096e95c0SMatthew Dillon 189096e95c0SMatthew Dillon /* 19000a3fdcaSMatthew Dillon * Initialize our marker for the inactive scan (SWAPC_WRITING) 191096e95c0SMatthew Dillon */ 19200a3fdcaSMatthew Dillon bzero(&page_marker, sizeof(page_marker)); 19351c99c61SMatthew Dillon for (q = 0; q < PQ_L2_SIZE; ++q) { 194bc0aa189SMatthew Dillon page_marker[q].flags = PG_FICTITIOUS | PG_MARKER; 195bc0aa189SMatthew Dillon page_marker[q].busy_count = PBUSY_LOCKED; 196027193ebSMatthew Dillon page_marker[q].queue = PQ_INACTIVE + q; 197027193ebSMatthew Dillon page_marker[q].pc = q; 198027193ebSMatthew Dillon page_marker[q].wire_count = 1; 199027193ebSMatthew Dillon vm_page_queues_spin_lock(PQ_INACTIVE + q); 200027193ebSMatthew Dillon TAILQ_INSERT_HEAD( 201027193ebSMatthew Dillon &vm_page_queues[PQ_INACTIVE + q].pl, 202027193ebSMatthew Dillon &page_marker[q], pageq); 203027193ebSMatthew Dillon vm_page_queues_spin_unlock(PQ_INACTIVE + q); 204027193ebSMatthew Dillon } 205b12defdcSMatthew Dillon 20664949baaSMatthew Dillon vm_swapcache_min_hysteresis = 1024; 20764949baaSMatthew Dillon vm_swapcache_hysteresis = vm_swapcache_min_hysteresis; 208e527fb6bSMatthew Dillon vm_swapcache_inactive_heuristic = -vm_swapcache_hysteresis; 209096e95c0SMatthew Dillon 21000a3fdcaSMatthew Dillon /* 21100a3fdcaSMatthew Dillon * Initialize our marker for the vm_object scan (SWAPC_CLEANING) 21200a3fdcaSMatthew Dillon */ 2137b00fbb4SMatthew Dillon bzero(&swmarker, sizeof(swmarker)); 2147b00fbb4SMatthew Dillon swmarker.type = OBJT_MARKER; 215fde6be6aSMatthew Dillon swindex = &vm_object_hash[0]; 216fde6be6aSMatthew Dillon lwkt_gettoken(&swindex->token); 217fde6be6aSMatthew Dillon TAILQ_INSERT_HEAD(&swindex->list, &swmarker, object_list); 218fde6be6aSMatthew Dillon lwkt_reltoken(&swindex->token); 219096e95c0SMatthew Dillon 220096e95c0SMatthew Dillon for (;;) { 22164949baaSMatthew Dillon int reached_end; 22264949baaSMatthew Dillon int scount; 22364949baaSMatthew Dillon int count; 22464949baaSMatthew Dillon 225096e95c0SMatthew Dillon /* 226497524bfSMatthew Dillon * Handle shutdown 227497524bfSMatthew Dillon */ 228497524bfSMatthew Dillon kproc_suspend_loop(); 229497524bfSMatthew Dillon 230497524bfSMatthew Dillon /* 2313da46bd7SMatthew Dillon * Check every 5 seconds when not enabled or if no swap 2323da46bd7SMatthew Dillon * is present. 233096e95c0SMatthew Dillon */ 2343da46bd7SMatthew Dillon if ((vm_swapcache_data_enable == 0 && 235c8ddd5d8SMatthew Dillon vm_swapcache_meta_enable == 0 && 236c8ddd5d8SMatthew Dillon vm_swap_cache_use <= SWAPMAX(0)) || 2373da46bd7SMatthew Dillon vm_swap_max == 0) { 238096e95c0SMatthew Dillon tsleep(&vm_swapcache_sleep, 0, "csleep", hz * 5); 239096e95c0SMatthew Dillon continue; 240096e95c0SMatthew Dillon } 241c504e38eSMatthew Dillon 242c504e38eSMatthew Dillon /* 2433da46bd7SMatthew Dillon * Polling rate when enabled is approximately 10 hz. 244c504e38eSMatthew Dillon */ 245c504e38eSMatthew Dillon tsleep(&vm_swapcache_sleep, 0, "csleep", hz / 10); 24600a3fdcaSMatthew Dillon 24700a3fdcaSMatthew Dillon /* 24800a3fdcaSMatthew Dillon * State hysteresis. Generate write activity up to 75% of 24900a3fdcaSMatthew Dillon * swap, then clean out swap assignments down to 70%, then 25000a3fdcaSMatthew Dillon * repeat. 25100a3fdcaSMatthew Dillon */ 25200a3fdcaSMatthew Dillon if (state == SWAPC_WRITING) { 253e9b56058SMatthew Dillon if (vm_swap_cache_use > SWAPMAX(0)) 25400a3fdcaSMatthew Dillon state = SWAPC_CLEANING; 25500a3fdcaSMatthew Dillon } else { 25608fb7a9dSMatthew Dillon if (vm_swap_cache_use < SWAPMAX(-10)) 25700a3fdcaSMatthew Dillon state = SWAPC_WRITING; 25800a3fdcaSMatthew Dillon } 25900a3fdcaSMatthew Dillon 26000a3fdcaSMatthew Dillon /* 26100a3fdcaSMatthew Dillon * We are allowed to continue accumulating burst value 2623ffc7051SMatthew Dillon * in either state. Allow the user to set curburst > maxburst 2633ffc7051SMatthew Dillon * for the initial load-in. 26400a3fdcaSMatthew Dillon */ 2653ffc7051SMatthew Dillon if (vm_swapcache_curburst < vm_swapcache_maxburst) { 266c504e38eSMatthew Dillon vm_swapcache_curburst += vm_swapcache_accrate / 10; 267c504e38eSMatthew Dillon if (vm_swapcache_curburst > vm_swapcache_maxburst) 268c504e38eSMatthew Dillon vm_swapcache_curburst = vm_swapcache_maxburst; 2693ffc7051SMatthew Dillon } 270c504e38eSMatthew Dillon 271c504e38eSMatthew Dillon /* 27200a3fdcaSMatthew Dillon * We don't want to nickle-and-dime the scan as that will 27300a3fdcaSMatthew Dillon * create unnecessary fragmentation. The minimum burst 27400a3fdcaSMatthew Dillon * is one-seconds worth of accumulation. 275c504e38eSMatthew Dillon */ 27664949baaSMatthew Dillon if (state != SWAPC_WRITING) { 2777b00fbb4SMatthew Dillon vm_swapcache_cleaning(&swmarker, &swindex); 27864949baaSMatthew Dillon continue; 27964949baaSMatthew Dillon } 28064949baaSMatthew Dillon if (vm_swapcache_curburst < vm_swapcache_accrate) 28164949baaSMatthew Dillon continue; 28264949baaSMatthew Dillon 28364949baaSMatthew Dillon reached_end = 0; 28464949baaSMatthew Dillon count = vm_swapcache_maxlaunder / PQ_L2_SIZE + 2; 28564949baaSMatthew Dillon scount = vm_swapcache_maxscan / PQ_L2_SIZE + 2; 28664949baaSMatthew Dillon 2873ffc7051SMatthew Dillon if (burst == SWAPB_BURSTING) { 28864949baaSMatthew Dillon if (vm_swapcache_writing_heuristic()) { 28951c99c61SMatthew Dillon for (q = 0; q < PQ_L2_SIZE; ++q) { 29064949baaSMatthew Dillon reached_end += 291027193ebSMatthew Dillon vm_swapcache_writing( 29264949baaSMatthew Dillon &page_marker[q], 29364949baaSMatthew Dillon count, 29464949baaSMatthew Dillon scount); 29564949baaSMatthew Dillon } 296027193ebSMatthew Dillon } 2973ffc7051SMatthew Dillon if (vm_swapcache_curburst <= 0) 2983ffc7051SMatthew Dillon burst = SWAPB_RECOVERING; 29964949baaSMatthew Dillon } else if (vm_swapcache_curburst > vm_swapcache_minburst) { 30064949baaSMatthew Dillon if (vm_swapcache_writing_heuristic()) { 30151c99c61SMatthew Dillon for (q = 0; q < PQ_L2_SIZE; ++q) { 30264949baaSMatthew Dillon reached_end += 303027193ebSMatthew Dillon vm_swapcache_writing( 30464949baaSMatthew Dillon &page_marker[q], 30564949baaSMatthew Dillon count, 30664949baaSMatthew Dillon scount); 30764949baaSMatthew Dillon } 308027193ebSMatthew Dillon } 3093ffc7051SMatthew Dillon burst = SWAPB_BURSTING; 3103ffc7051SMatthew Dillon } 31164949baaSMatthew Dillon if (reached_end == PQ_L2_SIZE) { 31264949baaSMatthew Dillon vm_swapcache_inactive_heuristic = 31364949baaSMatthew Dillon -vm_swapcache_hysteresis; 31400a3fdcaSMatthew Dillon } 31500a3fdcaSMatthew Dillon } 316eccc8ca1SMatthew Dillon 317eccc8ca1SMatthew Dillon /* 318eccc8ca1SMatthew Dillon * Cleanup (NOT REACHED) 319eccc8ca1SMatthew Dillon */ 32051c99c61SMatthew Dillon for (q = 0; q < PQ_L2_SIZE; ++q) { 321027193ebSMatthew Dillon vm_page_queues_spin_lock(PQ_INACTIVE + q); 322027193ebSMatthew Dillon TAILQ_REMOVE( 323027193ebSMatthew Dillon &vm_page_queues[PQ_INACTIVE + q].pl, 324027193ebSMatthew Dillon &page_marker[q], pageq); 325027193ebSMatthew Dillon vm_page_queues_spin_unlock(PQ_INACTIVE + q); 326027193ebSMatthew Dillon } 327eccc8ca1SMatthew Dillon 328fde6be6aSMatthew Dillon lwkt_gettoken(&swindex->token); 329fde6be6aSMatthew Dillon TAILQ_REMOVE(&swindex->list, &swmarker, object_list); 330fde6be6aSMatthew Dillon lwkt_reltoken(&swindex->token); 33100a3fdcaSMatthew Dillon } 332096e95c0SMatthew Dillon 333cd8ab232SMatthew Dillon static struct kproc_desc swpc_kp = { 334cd8ab232SMatthew Dillon "swapcached", 335cd8ab232SMatthew Dillon vm_swapcached_thread, 336cd8ab232SMatthew Dillon &swapcached_thread 337cd8ab232SMatthew Dillon }; 338f3f3eadbSSascha Wildner SYSINIT(swapcached, SI_SUB_KTHREAD_PAGE, SI_ORDER_SECOND, kproc_start, &swpc_kp); 339cd8ab232SMatthew Dillon 340096e95c0SMatthew Dillon /* 341fdc53cc7SMatthew Dillon * Deal with an overflow of the heuristic counter or if the user 342fdc53cc7SMatthew Dillon * manually changes the hysteresis. 343fdc53cc7SMatthew Dillon * 344e527fb6bSMatthew Dillon * Try to avoid small incremental pageouts by waiting for enough 345e527fb6bSMatthew Dillon * pages to buildup in the inactive queue to hopefully get a good 346e527fb6bSMatthew Dillon * burst in. This heuristic is bumped by the VM system and reset 347e527fb6bSMatthew Dillon * when our scan hits the end of the queue. 34864949baaSMatthew Dillon * 34964949baaSMatthew Dillon * Return TRUE if we need to take a writing pass. 350e527fb6bSMatthew Dillon */ 35164949baaSMatthew Dillon static int 35264949baaSMatthew Dillon vm_swapcache_writing_heuristic(void) 35364949baaSMatthew Dillon { 35464949baaSMatthew Dillon int hyst; 35564949baaSMatthew Dillon 35664949baaSMatthew Dillon hyst = vmstats.v_inactive_count / 4; 35764949baaSMatthew Dillon if (hyst < vm_swapcache_min_hysteresis) 35864949baaSMatthew Dillon hyst = vm_swapcache_min_hysteresis; 35964949baaSMatthew Dillon cpu_ccfence(); 36064949baaSMatthew Dillon vm_swapcache_hysteresis = hyst; 36164949baaSMatthew Dillon 36264949baaSMatthew Dillon if (vm_swapcache_inactive_heuristic < -hyst) 36364949baaSMatthew Dillon vm_swapcache_inactive_heuristic = -hyst; 36464949baaSMatthew Dillon 36564949baaSMatthew Dillon return (vm_swapcache_inactive_heuristic >= 0); 36664949baaSMatthew Dillon } 36764949baaSMatthew Dillon 36864949baaSMatthew Dillon /* 36964949baaSMatthew Dillon * Take a writing pass on one of the inactive queues, return non-zero if 37064949baaSMatthew Dillon * we hit the end of the queue. 37164949baaSMatthew Dillon */ 37264949baaSMatthew Dillon static int 37364949baaSMatthew Dillon vm_swapcache_writing(vm_page_t marker, int count, int scount) 37464949baaSMatthew Dillon { 37564949baaSMatthew Dillon vm_object_t object; 37664949baaSMatthew Dillon struct vnode *vp; 37764949baaSMatthew Dillon vm_page_t m; 37864949baaSMatthew Dillon int isblkdev; 379e527fb6bSMatthew Dillon 380e527fb6bSMatthew Dillon /* 381096e95c0SMatthew Dillon * Scan the inactive queue from our marker to locate 382096e95c0SMatthew Dillon * suitable pages to push to the swap cache. 383096e95c0SMatthew Dillon * 384096e95c0SMatthew Dillon * We are looking for clean vnode-backed pages. 385096e95c0SMatthew Dillon */ 386027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 3870bf81261SMatthew Dillon while ((m = TAILQ_NEXT(marker, pageq)) != NULL && 3880bf81261SMatthew Dillon count > 0 && scount-- > 0) { 389027193ebSMatthew Dillon KKASSERT(m->queue == marker->queue); 390b12defdcSMatthew Dillon 3911de864f0SMatthew Dillon /* 3921de864f0SMatthew Dillon * Stop using swap if paniced, dumping, or dumped. 3931de864f0SMatthew Dillon * Don't try to write if our curburst has been exhausted. 3941de864f0SMatthew Dillon */ 3951de864f0SMatthew Dillon if (panicstr || dumping) 3961de864f0SMatthew Dillon break; 397b12defdcSMatthew Dillon if (vm_swapcache_curburst < 0) 398b12defdcSMatthew Dillon break; 3991de864f0SMatthew Dillon 4001de864f0SMatthew Dillon /* 4011de864f0SMatthew Dillon * Move marker 4021de864f0SMatthew Dillon */ 403027193ebSMatthew Dillon TAILQ_REMOVE( 404027193ebSMatthew Dillon &vm_page_queues[marker->queue].pl, marker, pageq); 405027193ebSMatthew Dillon TAILQ_INSERT_AFTER( 406027193ebSMatthew Dillon &vm_page_queues[marker->queue].pl, m, marker, pageq); 407f5f6d247SMatthew Dillon 408f5f6d247SMatthew Dillon /* 409f5f6d247SMatthew Dillon * Ignore markers and ignore pages that already have a swap 410f5f6d247SMatthew Dillon * assignment. 411f5f6d247SMatthew Dillon */ 4120bf81261SMatthew Dillon if (m->flags & (PG_MARKER | PG_SWAPPED)) 413096e95c0SMatthew Dillon continue; 414b12defdcSMatthew Dillon if (vm_page_busy_try(m, TRUE)) 415096e95c0SMatthew Dillon continue; 416027193ebSMatthew Dillon vm_page_queues_spin_unlock(marker->queue); 417b12defdcSMatthew Dillon 418b12defdcSMatthew Dillon if ((object = m->object) == NULL) { 419b12defdcSMatthew Dillon vm_page_wakeup(m); 420027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 421b12defdcSMatthew Dillon continue; 422b12defdcSMatthew Dillon } 423b12defdcSMatthew Dillon vm_object_hold(object); 424b12defdcSMatthew Dillon if (m->object != object) { 425b12defdcSMatthew Dillon vm_object_drop(object); 426b12defdcSMatthew Dillon vm_page_wakeup(m); 427027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 428b12defdcSMatthew Dillon continue; 429b12defdcSMatthew Dillon } 430b12defdcSMatthew Dillon if (vm_swapcache_test(m)) { 431b12defdcSMatthew Dillon vm_object_drop(object); 432b12defdcSMatthew Dillon vm_page_wakeup(m); 433027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 434b12defdcSMatthew Dillon continue; 435b12defdcSMatthew Dillon } 436b12defdcSMatthew Dillon 437c504e38eSMatthew Dillon vp = object->handle; 438b12defdcSMatthew Dillon if (vp == NULL) { 439b12defdcSMatthew Dillon vm_object_drop(object); 440b12defdcSMatthew Dillon vm_page_wakeup(m); 441027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 442c504e38eSMatthew Dillon continue; 443b12defdcSMatthew Dillon } 444d3070b8dSMatthew Dillon 445c504e38eSMatthew Dillon switch(vp->v_type) { 446c504e38eSMatthew Dillon case VREG: 447e9b56058SMatthew Dillon /* 448bfa86281SMatthew Dillon * PG_NOTMETA generically means 'don't swapcache this', 449bfa86281SMatthew Dillon * and HAMMER will set this for regular data buffers 450bfa86281SMatthew Dillon * (and leave it unset for meta-data buffers) as 451bfa86281SMatthew Dillon * appropriate when double buffering is enabled. 452bfa86281SMatthew Dillon */ 453b12defdcSMatthew Dillon if (m->flags & PG_NOTMETA) { 454b12defdcSMatthew Dillon vm_object_drop(object); 455b12defdcSMatthew Dillon vm_page_wakeup(m); 456027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 457bfa86281SMatthew Dillon continue; 458b12defdcSMatthew Dillon } 459bfa86281SMatthew Dillon 460bfa86281SMatthew Dillon /* 461e9b56058SMatthew Dillon * If data_enable is 0 do not try to swapcache data. 462e9b56058SMatthew Dillon * If use_chflags is set then only swapcache data for 463e9b56058SMatthew Dillon * VSWAPCACHE marked vnodes, otherwise any vnode. 464e9b56058SMatthew Dillon */ 465e9b56058SMatthew Dillon if (vm_swapcache_data_enable == 0 || 466e9b56058SMatthew Dillon ((vp->v_flag & VSWAPCACHE) == 0 && 467e9b56058SMatthew Dillon vm_swapcache_use_chflags)) { 468b12defdcSMatthew Dillon vm_object_drop(object); 469b12defdcSMatthew Dillon vm_page_wakeup(m); 470027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 471c504e38eSMatthew Dillon continue; 472e9b56058SMatthew Dillon } 473d3070b8dSMatthew Dillon if (vm_swapcache_maxfilesize && 474d3070b8dSMatthew Dillon object->size > 475d3070b8dSMatthew Dillon (vm_swapcache_maxfilesize >> PAGE_SHIFT)) { 476b12defdcSMatthew Dillon vm_object_drop(object); 477b12defdcSMatthew Dillon vm_page_wakeup(m); 478027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 479d3070b8dSMatthew Dillon continue; 480d3070b8dSMatthew Dillon } 481aabd5ce8SMatthew Dillon isblkdev = 0; 482c504e38eSMatthew Dillon break; 483c504e38eSMatthew Dillon case VCHR: 484aabd5ce8SMatthew Dillon /* 485bfa86281SMatthew Dillon * PG_NOTMETA generically means 'don't swapcache this', 486bfa86281SMatthew Dillon * and HAMMER will set this for regular data buffers 487bfa86281SMatthew Dillon * (and leave it unset for meta-data buffers) as 488bfa86281SMatthew Dillon * appropriate when double buffering is enabled. 489aabd5ce8SMatthew Dillon */ 490b12defdcSMatthew Dillon if (m->flags & PG_NOTMETA) { 491b12defdcSMatthew Dillon vm_object_drop(object); 492b12defdcSMatthew Dillon vm_page_wakeup(m); 493027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 494aabd5ce8SMatthew Dillon continue; 495b12defdcSMatthew Dillon } 496b12defdcSMatthew Dillon if (vm_swapcache_meta_enable == 0) { 497b12defdcSMatthew Dillon vm_object_drop(object); 498b12defdcSMatthew Dillon vm_page_wakeup(m); 499027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 500c504e38eSMatthew Dillon continue; 501b12defdcSMatthew Dillon } 502aabd5ce8SMatthew Dillon isblkdev = 1; 503c504e38eSMatthew Dillon break; 504c504e38eSMatthew Dillon default: 505b12defdcSMatthew Dillon vm_object_drop(object); 506b12defdcSMatthew Dillon vm_page_wakeup(m); 507027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 508c504e38eSMatthew Dillon continue; 509c504e38eSMatthew Dillon } 510096e95c0SMatthew Dillon 511096e95c0SMatthew Dillon 512096e95c0SMatthew Dillon /* 5133ffc7051SMatthew Dillon * Assign swap and initiate I/O. 5143ffc7051SMatthew Dillon * 5153ffc7051SMatthew Dillon * (adjust for the --count which also occurs in the loop) 516096e95c0SMatthew Dillon */ 5170bf81261SMatthew Dillon count -= vm_swapcached_flush(m, isblkdev); 518096e95c0SMatthew Dillon 519096e95c0SMatthew Dillon /* 520096e95c0SMatthew Dillon * Setup for next loop using marker. 521096e95c0SMatthew Dillon */ 522b12defdcSMatthew Dillon vm_object_drop(object); 523027193ebSMatthew Dillon vm_page_queues_spin_lock(marker->queue); 524096e95c0SMatthew Dillon } 5251e5196f0SMatthew Dillon 5261e5196f0SMatthew Dillon /* 527b12defdcSMatthew Dillon * The marker could wind up at the end, which is ok. If we hit the 528b12defdcSMatthew Dillon * end of the list adjust the heuristic. 5291e5196f0SMatthew Dillon * 5301e5196f0SMatthew Dillon * Earlier inactive pages that were dirty and become clean 5311e5196f0SMatthew Dillon * are typically moved to the end of PQ_INACTIVE by virtue 5321e5196f0SMatthew Dillon * of vfs_vmio_release() when they become unwired from the 5331e5196f0SMatthew Dillon * buffer cache. 5341e5196f0SMatthew Dillon */ 535027193ebSMatthew Dillon vm_page_queues_spin_unlock(marker->queue); 53664949baaSMatthew Dillon 53764949baaSMatthew Dillon /* 53864949baaSMatthew Dillon * m invalid but can be used to test for NULL 53964949baaSMatthew Dillon */ 54064949baaSMatthew Dillon return (m == NULL); 541096e95c0SMatthew Dillon } 542096e95c0SMatthew Dillon 543096e95c0SMatthew Dillon /* 544b12defdcSMatthew Dillon * Flush the specified page using the swap_pager. The page 545b12defdcSMatthew Dillon * must be busied by the caller and its disposition will become 546b12defdcSMatthew Dillon * the responsibility of this function. 5473ffc7051SMatthew Dillon * 5483ffc7051SMatthew Dillon * Try to collect surrounding pages, including pages which may 5493ffc7051SMatthew Dillon * have already been assigned swap. Try to cluster within a 5503ffc7051SMatthew Dillon * contiguous aligned SMAP_META_PAGES (typ 16 x PAGE_SIZE) block 5513ffc7051SMatthew Dillon * to match what swap_pager_putpages() can do. 5523ffc7051SMatthew Dillon * 5533ffc7051SMatthew Dillon * We also want to try to match against the buffer cache blocksize 5543ffc7051SMatthew Dillon * but we don't really know what it is here. Since the buffer cache 5553ffc7051SMatthew Dillon * wires and unwires pages in groups the fact that we skip wired pages 5563ffc7051SMatthew Dillon * should be sufficient. 5573ffc7051SMatthew Dillon * 5583ffc7051SMatthew Dillon * Returns a count of pages we might have flushed (minimum 1) 559096e95c0SMatthew Dillon */ 560096e95c0SMatthew Dillon static 5613ffc7051SMatthew Dillon int 562aabd5ce8SMatthew Dillon vm_swapcached_flush(vm_page_t m, int isblkdev) 563096e95c0SMatthew Dillon { 564096e95c0SMatthew Dillon vm_object_t object; 5653ffc7051SMatthew Dillon vm_page_t marray[SWAP_META_PAGES]; 5663ffc7051SMatthew Dillon vm_pindex_t basei; 5673ffc7051SMatthew Dillon int rtvals[SWAP_META_PAGES]; 5683ffc7051SMatthew Dillon int x; 5693ffc7051SMatthew Dillon int i; 5703ffc7051SMatthew Dillon int j; 5713ffc7051SMatthew Dillon int count; 572b12defdcSMatthew Dillon int error; 573096e95c0SMatthew Dillon 574096e95c0SMatthew Dillon vm_page_io_start(m); 575096e95c0SMatthew Dillon vm_page_protect(m, VM_PROT_READ); 576096e95c0SMatthew Dillon object = m->object; 577b12defdcSMatthew Dillon vm_object_hold(object); 578096e95c0SMatthew Dillon 5793ffc7051SMatthew Dillon /* 5803ffc7051SMatthew Dillon * Try to cluster around (m), keeping in mind that the swap pager 5813ffc7051SMatthew Dillon * can only do SMAP_META_PAGES worth of continguous write. 5823ffc7051SMatthew Dillon */ 5833ffc7051SMatthew Dillon x = (int)m->pindex & SWAP_META_MASK; 5843ffc7051SMatthew Dillon marray[x] = m; 5853ffc7051SMatthew Dillon basei = m->pindex; 586b12defdcSMatthew Dillon vm_page_wakeup(m); 5873ffc7051SMatthew Dillon 5883ffc7051SMatthew Dillon for (i = x - 1; i >= 0; --i) { 589b12defdcSMatthew Dillon m = vm_page_lookup_busy_try(object, basei - x + i, 590b12defdcSMatthew Dillon TRUE, &error); 591b12defdcSMatthew Dillon if (error || m == NULL) 5923ffc7051SMatthew Dillon break; 593b12defdcSMatthew Dillon if (vm_swapcache_test(m)) { 594b12defdcSMatthew Dillon vm_page_wakeup(m); 5953ffc7051SMatthew Dillon break; 596b12defdcSMatthew Dillon } 597b12defdcSMatthew Dillon if (isblkdev && (m->flags & PG_NOTMETA)) { 598b12defdcSMatthew Dillon vm_page_wakeup(m); 599aabd5ce8SMatthew Dillon break; 600b12defdcSMatthew Dillon } 6013ffc7051SMatthew Dillon vm_page_io_start(m); 6023ffc7051SMatthew Dillon vm_page_protect(m, VM_PROT_READ); 6033ffc7051SMatthew Dillon if (m->queue - m->pc == PQ_CACHE) { 6043ffc7051SMatthew Dillon vm_page_unqueue_nowakeup(m); 6053ffc7051SMatthew Dillon vm_page_deactivate(m); 6063ffc7051SMatthew Dillon } 6073ffc7051SMatthew Dillon marray[i] = m; 608b12defdcSMatthew Dillon vm_page_wakeup(m); 6093ffc7051SMatthew Dillon } 6103ffc7051SMatthew Dillon ++i; 6113ffc7051SMatthew Dillon 6123ffc7051SMatthew Dillon for (j = x + 1; j < SWAP_META_PAGES; ++j) { 613b12defdcSMatthew Dillon m = vm_page_lookup_busy_try(object, basei - x + j, 614b12defdcSMatthew Dillon TRUE, &error); 615b12defdcSMatthew Dillon if (error || m == NULL) 6163ffc7051SMatthew Dillon break; 617b12defdcSMatthew Dillon if (vm_swapcache_test(m)) { 618b12defdcSMatthew Dillon vm_page_wakeup(m); 6193ffc7051SMatthew Dillon break; 620b12defdcSMatthew Dillon } 621b12defdcSMatthew Dillon if (isblkdev && (m->flags & PG_NOTMETA)) { 622b12defdcSMatthew Dillon vm_page_wakeup(m); 623aabd5ce8SMatthew Dillon break; 624b12defdcSMatthew Dillon } 6253ffc7051SMatthew Dillon vm_page_io_start(m); 6263ffc7051SMatthew Dillon vm_page_protect(m, VM_PROT_READ); 6273ffc7051SMatthew Dillon if (m->queue - m->pc == PQ_CACHE) { 6283ffc7051SMatthew Dillon vm_page_unqueue_nowakeup(m); 6293ffc7051SMatthew Dillon vm_page_deactivate(m); 6303ffc7051SMatthew Dillon } 6313ffc7051SMatthew Dillon marray[j] = m; 632b12defdcSMatthew Dillon vm_page_wakeup(m); 6333ffc7051SMatthew Dillon } 6343ffc7051SMatthew Dillon 6353ffc7051SMatthew Dillon count = j - i; 6363ffc7051SMatthew Dillon vm_object_pip_add(object, count); 6373ffc7051SMatthew Dillon swap_pager_putpages(object, marray + i, count, FALSE, rtvals + i); 6383ffc7051SMatthew Dillon vm_swapcache_write_count += count * PAGE_SIZE; 6393ffc7051SMatthew Dillon vm_swapcache_curburst -= count * PAGE_SIZE; 6403ffc7051SMatthew Dillon 6413ffc7051SMatthew Dillon while (i < j) { 6423ffc7051SMatthew Dillon if (rtvals[i] != VM_PAGER_PEND) { 643b12defdcSMatthew Dillon vm_page_busy_wait(marray[i], FALSE, "swppgfd"); 6443ffc7051SMatthew Dillon vm_page_io_finish(marray[i]); 645b12defdcSMatthew Dillon vm_page_wakeup(marray[i]); 646096e95c0SMatthew Dillon vm_object_pip_wakeup(object); 647096e95c0SMatthew Dillon } 6483ffc7051SMatthew Dillon ++i; 6493ffc7051SMatthew Dillon } 650b12defdcSMatthew Dillon vm_object_drop(object); 6513ffc7051SMatthew Dillon return(count); 652096e95c0SMatthew Dillon } 65300a3fdcaSMatthew Dillon 6543ffc7051SMatthew Dillon /* 6553ffc7051SMatthew Dillon * Test whether a VM page is suitable for writing to the swapcache. 6563ffc7051SMatthew Dillon * Does not test m->queue, PG_MARKER, or PG_SWAPPED. 6573ffc7051SMatthew Dillon * 6583ffc7051SMatthew Dillon * Returns 0 on success, 1 on failure 6593ffc7051SMatthew Dillon */ 6603ffc7051SMatthew Dillon static int 6613ffc7051SMatthew Dillon vm_swapcache_test(vm_page_t m) 6623ffc7051SMatthew Dillon { 6633ffc7051SMatthew Dillon vm_object_t object; 6643ffc7051SMatthew Dillon 665b12defdcSMatthew Dillon if (m->flags & PG_UNMANAGED) 6663ffc7051SMatthew Dillon return(1); 667b12defdcSMatthew Dillon if (m->hold_count || m->wire_count) 6683ffc7051SMatthew Dillon return(1); 6693ffc7051SMatthew Dillon if (m->valid != VM_PAGE_BITS_ALL) 6703ffc7051SMatthew Dillon return(1); 6713ffc7051SMatthew Dillon if (m->dirty & m->valid) 6723ffc7051SMatthew Dillon return(1); 6733ffc7051SMatthew Dillon if ((object = m->object) == NULL) 6743ffc7051SMatthew Dillon return(1); 6753ffc7051SMatthew Dillon if (object->type != OBJT_VNODE || 6763ffc7051SMatthew Dillon (object->flags & OBJ_DEAD)) { 6773ffc7051SMatthew Dillon return(1); 6783ffc7051SMatthew Dillon } 6793ffc7051SMatthew Dillon vm_page_test_dirty(m); 6803ffc7051SMatthew Dillon if (m->dirty & m->valid) 6813ffc7051SMatthew Dillon return(1); 6823ffc7051SMatthew Dillon return(0); 6833ffc7051SMatthew Dillon } 6843ffc7051SMatthew Dillon 6853ffc7051SMatthew Dillon /* 686f5f6d247SMatthew Dillon * Cleaning pass. 687f5f6d247SMatthew Dillon * 688f5f6d247SMatthew Dillon * We clean whole objects up to 16MB 6893ffc7051SMatthew Dillon */ 69000a3fdcaSMatthew Dillon static 69100a3fdcaSMatthew Dillon void 692fde6be6aSMatthew Dillon vm_swapcache_cleaning(vm_object_t marker, struct vm_object_hash **swindexp) 69300a3fdcaSMatthew Dillon { 69400a3fdcaSMatthew Dillon vm_object_t object; 69500a3fdcaSMatthew Dillon struct vnode *vp; 69600a3fdcaSMatthew Dillon int count; 6970bf81261SMatthew Dillon int scount; 69800a3fdcaSMatthew Dillon int n; 699*eea5ad68SMatthew Dillon int didmove; 70000a3fdcaSMatthew Dillon 70100a3fdcaSMatthew Dillon count = vm_swapcache_maxlaunder; 7020bf81261SMatthew Dillon scount = vm_swapcache_maxscan; 70300a3fdcaSMatthew Dillon 70400a3fdcaSMatthew Dillon /* 70500a3fdcaSMatthew Dillon * Look for vnode objects 70600a3fdcaSMatthew Dillon */ 707fde6be6aSMatthew Dillon lwkt_gettoken(&(*swindexp)->token); 7082de4f77eSMatthew Dillon 709*eea5ad68SMatthew Dillon didmove = 0; 710b2286ce7SMatthew Dillon outerloop: 711f5f6d247SMatthew Dillon while ((object = TAILQ_NEXT(marker, object_list)) != NULL) { 7122f2d9e58SVenkatesh Srinivas /* 713f5f6d247SMatthew Dillon * We have to skip markers. We cannot hold/drop marker 714f5f6d247SMatthew Dillon * objects! 7152f2d9e58SVenkatesh Srinivas */ 716f5f6d247SMatthew Dillon if (object->type == OBJT_MARKER) { 7177b00fbb4SMatthew Dillon vm_swapcache_movemarker(marker, *swindexp, object); 718*eea5ad68SMatthew Dillon didmove = 1; 71900a3fdcaSMatthew Dillon continue; 7202f2d9e58SVenkatesh Srinivas } 72100a3fdcaSMatthew Dillon 72200a3fdcaSMatthew Dillon /* 723f5f6d247SMatthew Dillon * Safety, or in case there are millions of VM objects 724f5f6d247SMatthew Dillon * without swapcache backing. 72500a3fdcaSMatthew Dillon */ 7260bf81261SMatthew Dillon if (--scount <= 0) 7277b00fbb4SMatthew Dillon goto breakout; 72800a3fdcaSMatthew Dillon 72900a3fdcaSMatthew Dillon /* 730f5f6d247SMatthew Dillon * We must hold the object before potentially yielding. 73100a3fdcaSMatthew Dillon */ 732f5f6d247SMatthew Dillon vm_object_hold(object); 733f5f6d247SMatthew Dillon lwkt_yield(); 734f5f6d247SMatthew Dillon 735f5f6d247SMatthew Dillon /* 736f5f6d247SMatthew Dillon * Only operate on live VNODE objects that are either 737f5f6d247SMatthew Dillon * VREG or VCHR (VCHR for meta-data). 738f5f6d247SMatthew Dillon */ 739f5f6d247SMatthew Dillon if ((object->type != OBJT_VNODE) || 740f5f6d247SMatthew Dillon ((object->flags & OBJ_DEAD) || 741f5f6d247SMatthew Dillon object->swblock_count == 0) || 742f5f6d247SMatthew Dillon ((vp = object->handle) == NULL) || 743f5f6d247SMatthew Dillon (vp->v_type != VREG && vp->v_type != VCHR)) { 744f5f6d247SMatthew Dillon vm_object_drop(object); 745f5f6d247SMatthew Dillon /* object may be invalid now */ 7467b00fbb4SMatthew Dillon vm_swapcache_movemarker(marker, *swindexp, object); 747*eea5ad68SMatthew Dillon didmove = 1; 748f5f6d247SMatthew Dillon continue; 749f5f6d247SMatthew Dillon } 750f5f6d247SMatthew Dillon 751f5f6d247SMatthew Dillon /* 752f5f6d247SMatthew Dillon * Reset the object pindex stored in the marker if the 753f5f6d247SMatthew Dillon * working object has changed. 754f5f6d247SMatthew Dillon */ 755*eea5ad68SMatthew Dillon if (marker->backing_object != object || didmove) { 756f5f6d247SMatthew Dillon marker->size = 0; 757f5f6d247SMatthew Dillon marker->backing_object_offset = 0; 758f5f6d247SMatthew Dillon marker->backing_object = object; 759*eea5ad68SMatthew Dillon didmove = 0; 760f5f6d247SMatthew Dillon } 76100a3fdcaSMatthew Dillon 76200a3fdcaSMatthew Dillon /* 76300a3fdcaSMatthew Dillon * Look for swblocks starting at our iterator. 76400a3fdcaSMatthew Dillon * 76500a3fdcaSMatthew Dillon * The swap_pager_condfree() function attempts to free 76600a3fdcaSMatthew Dillon * swap space starting at the specified index. The index 76700a3fdcaSMatthew Dillon * will be updated on return. The function will return 76800a3fdcaSMatthew Dillon * a scan factor (NOT the number of blocks freed). 76900a3fdcaSMatthew Dillon * 77000a3fdcaSMatthew Dillon * If it must cut its scan of the object short due to an 77100a3fdcaSMatthew Dillon * excessive number of swblocks, or is able to free the 77200a3fdcaSMatthew Dillon * requested number of blocks, it will return n >= count 77300a3fdcaSMatthew Dillon * and we break and pick it back up on a future attempt. 774f5f6d247SMatthew Dillon * 775f5f6d247SMatthew Dillon * Scan the object linearly and try to batch large sets of 776f5f6d247SMatthew Dillon * blocks that are likely to clean out entire swap radix 777f5f6d247SMatthew Dillon * tree leafs. 77800a3fdcaSMatthew Dillon */ 779739be60bSMatthew Dillon lwkt_token_swap(); 780fde6be6aSMatthew Dillon lwkt_reltoken(&(*swindexp)->token); 78127b6ee03SMatthew Dillon 782f5f6d247SMatthew Dillon n = swap_pager_condfree(object, &marker->size, 783f5f6d247SMatthew Dillon (count + SWAP_META_MASK) & ~SWAP_META_MASK); 7842f2d9e58SVenkatesh Srinivas 785f5f6d247SMatthew Dillon vm_object_drop(object); /* object may be invalid now */ 786fde6be6aSMatthew Dillon lwkt_gettoken(&(*swindexp)->token); 7872f2d9e58SVenkatesh Srinivas 78800a3fdcaSMatthew Dillon /* 789f5f6d247SMatthew Dillon * If we have exhausted the object or deleted our per-pass 790f5f6d247SMatthew Dillon * page limit then move us to the next object. Note that 791f5f6d247SMatthew Dillon * the current object may no longer be on the vm_object_list. 79200a3fdcaSMatthew Dillon */ 793f5f6d247SMatthew Dillon if (n <= 0 || 794f5f6d247SMatthew Dillon marker->backing_object_offset > vm_swapcache_cleanperobj) { 7957b00fbb4SMatthew Dillon vm_swapcache_movemarker(marker, *swindexp, object); 796*eea5ad68SMatthew Dillon didmove = 1; 79700a3fdcaSMatthew Dillon } 79800a3fdcaSMatthew Dillon 79900a3fdcaSMatthew Dillon /* 800f5f6d247SMatthew Dillon * If we have exhausted our max-launder stop for now. 80100a3fdcaSMatthew Dillon */ 802f5f6d247SMatthew Dillon count -= n; 803f5f6d247SMatthew Dillon marker->backing_object_offset += n * PAGE_SIZE; 804f5f6d247SMatthew Dillon if (count < 0) 8057b00fbb4SMatthew Dillon goto breakout; 806f5f6d247SMatthew Dillon } 8077a175765SMatthew Dillon 8087a175765SMatthew Dillon /* 8097b00fbb4SMatthew Dillon * Iterate vm_object_lists[] hash table 8107a175765SMatthew Dillon */ 811fde6be6aSMatthew Dillon TAILQ_REMOVE(&(*swindexp)->list, marker, object_list); 812fde6be6aSMatthew Dillon lwkt_reltoken(&(*swindexp)->token); 813fde6be6aSMatthew Dillon if (++*swindexp >= &vm_object_hash[VMOBJ_HSIZE]) 814fde6be6aSMatthew Dillon *swindexp = &vm_object_hash[0]; 815fde6be6aSMatthew Dillon lwkt_gettoken(&(*swindexp)->token); 816fde6be6aSMatthew Dillon TAILQ_INSERT_HEAD(&(*swindexp)->list, marker, object_list); 8177a175765SMatthew Dillon 818fde6be6aSMatthew Dillon if (*swindexp != &vm_object_hash[0]) 8197b00fbb4SMatthew Dillon goto outerloop; 8207b00fbb4SMatthew Dillon 8217b00fbb4SMatthew Dillon breakout: 822fde6be6aSMatthew Dillon lwkt_reltoken(&(*swindexp)->token); 82300a3fdcaSMatthew Dillon } 824f5f6d247SMatthew Dillon 825f5f6d247SMatthew Dillon /* 826f5f6d247SMatthew Dillon * Move the marker past the current object. Object can be stale, but we 827f5f6d247SMatthew Dillon * still need it to determine if the marker has to be moved. If the object 828f5f6d247SMatthew Dillon * is still the 'current object' (object after the marker), we hop-scotch 829f5f6d247SMatthew Dillon * the marker past it. 830f5f6d247SMatthew Dillon */ 831f5f6d247SMatthew Dillon static void 832fde6be6aSMatthew Dillon vm_swapcache_movemarker(vm_object_t marker, struct vm_object_hash *swindex, 833fde6be6aSMatthew Dillon vm_object_t object) 834f5f6d247SMatthew Dillon { 835f5f6d247SMatthew Dillon if (TAILQ_NEXT(marker, object_list) == object) { 836fde6be6aSMatthew Dillon TAILQ_REMOVE(&swindex->list, marker, object_list); 837fde6be6aSMatthew Dillon TAILQ_INSERT_AFTER(&swindex->list, object, marker, object_list); 838f5f6d247SMatthew Dillon } 839f5f6d247SMatthew Dillon } 840