SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * DAMON-based page reclamation |
| 4 | * |
| 5 | * Author: SeongJae Park <sj@kernel.org> |
| 6 | */ |
| 7 | |
| 8 | #define pr_fmt(fmt) "damon-reclaim: " fmt |
| 9 | |
| 10 | #include <linux/damon.h> |
Christophe JAILLET | e6aff38 | 2022-11-01 22:14:08 +0100 | [diff] [blame] | 11 | #include <linux/kstrtox.h> |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 12 | #include <linux/module.h> |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 13 | |
SeongJae Park | fdfc119 | 2022-09-13 17:44:38 +0000 | [diff] [blame] | 14 | #include "modules-common.h" |
| 15 | |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 16 | #ifdef MODULE_PARAM_PREFIX |
| 17 | #undef MODULE_PARAM_PREFIX |
| 18 | #endif |
| 19 | #define MODULE_PARAM_PREFIX "damon_reclaim." |
| 20 | |
| 21 | /* |
| 22 | * Enable or disable DAMON_RECLAIM. |
| 23 | * |
| 24 | * You can enable DAMON_RCLAIM by setting the value of this parameter as ``Y``. |
| 25 | * Setting it as ``N`` disables DAMON_RECLAIM. Note that DAMON_RECLAIM could |
| 26 | * do no real monitoring and reclamation due to the watermarks-based activation |
| 27 | * condition. Refer to below descriptions for the watermarks parameter for |
| 28 | * this. |
| 29 | */ |
| 30 | static bool enabled __read_mostly; |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 31 | |
| 32 | /* |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 33 | * Make DAMON_RECLAIM reads the input parameters again, except ``enabled``. |
| 34 | * |
| 35 | * Input parameters that updated while DAMON_RECLAIM is running are not applied |
| 36 | * by default. Once this parameter is set as ``Y``, DAMON_RECLAIM reads values |
| 37 | * of parametrs except ``enabled`` again. Once the re-reading is done, this |
| 38 | * parameter is set as ``N``. If invalid parameters are found while the |
| 39 | * re-reading, DAMON_RECLAIM will be disabled. |
| 40 | */ |
| 41 | static bool commit_inputs __read_mostly; |
| 42 | module_param(commit_inputs, bool, 0600); |
| 43 | |
| 44 | /* |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 45 | * Time threshold for cold memory regions identification in microseconds. |
| 46 | * |
| 47 | * If a memory region is not accessed for this or longer time, DAMON_RECLAIM |
| 48 | * identifies the region as cold, and reclaims. 120 seconds by default. |
| 49 | */ |
| 50 | static unsigned long min_age __read_mostly = 120000000; |
| 51 | module_param(min_age, ulong, 0600); |
| 52 | |
SeongJae Park | a9d57c7 | 2022-09-13 17:44:47 +0000 | [diff] [blame] | 53 | static struct damos_quota damon_reclaim_quota = { |
| 54 | /* use up to 10 ms time, reclaim up to 128 MiB per 1 sec by default */ |
| 55 | .ms = 10, |
| 56 | .sz = 128 * 1024 * 1024, |
| 57 | .reset_interval = 1000, |
| 58 | /* Within the quota, page out older regions first. */ |
| 59 | .weight_sz = 0, |
| 60 | .weight_nr_accesses = 0, |
| 61 | .weight_age = 1 |
| 62 | }; |
| 63 | DEFINE_DAMON_MODULES_DAMOS_QUOTAS(damon_reclaim_quota); |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 64 | |
Yang Yingliang | 81f8f57 | 2022-09-15 10:10:23 +0800 | [diff] [blame] | 65 | static struct damos_watermarks damon_reclaim_wmarks = { |
SeongJae Park | 34f47ea | 2022-09-13 17:44:41 +0000 | [diff] [blame] | 66 | .metric = DAMOS_WMARK_FREE_MEM_RATE, |
| 67 | .interval = 5000000, /* 5 seconds */ |
| 68 | .high = 500, /* 50 percent */ |
| 69 | .mid = 400, /* 40 percent */ |
| 70 | .low = 200, /* 20 percent */ |
| 71 | }; |
| 72 | DEFINE_DAMON_MODULES_WMARKS_PARAMS(damon_reclaim_wmarks); |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 73 | |
SeongJae Park | 8c341ae | 2022-09-13 17:44:34 +0000 | [diff] [blame] | 74 | static struct damon_attrs damon_reclaim_mon_attrs = { |
SeongJae Park | fdfc119 | 2022-09-13 17:44:38 +0000 | [diff] [blame] | 75 | .sample_interval = 5000, /* 5 ms */ |
| 76 | .aggr_interval = 100000, /* 100 ms */ |
SeongJae Park | 8c341ae | 2022-09-13 17:44:34 +0000 | [diff] [blame] | 77 | .ops_update_interval = 0, |
| 78 | .min_nr_regions = 10, |
| 79 | .max_nr_regions = 1000, |
| 80 | }; |
SeongJae Park | fdfc119 | 2022-09-13 17:44:38 +0000 | [diff] [blame] | 81 | DEFINE_DAMON_MODULES_MON_ATTRS_PARAMS(damon_reclaim_mon_attrs); |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 82 | |
| 83 | /* |
| 84 | * Start of the target memory region in physical address. |
| 85 | * |
| 86 | * The start physical address of memory region that DAMON_RECLAIM will do work |
| 87 | * against. By default, biggest System RAM is used as the region. |
| 88 | */ |
| 89 | static unsigned long monitor_region_start __read_mostly; |
| 90 | module_param(monitor_region_start, ulong, 0600); |
| 91 | |
| 92 | /* |
| 93 | * End of the target memory region in physical address. |
| 94 | * |
| 95 | * The end physical address of memory region that DAMON_RECLAIM will do work |
| 96 | * against. By default, biggest System RAM is used as the region. |
| 97 | */ |
| 98 | static unsigned long monitor_region_end __read_mostly; |
| 99 | module_param(monitor_region_end, ulong, 0600); |
| 100 | |
| 101 | /* |
SeongJae Park | 66d9fae | 2022-12-05 23:08:22 +0000 | [diff] [blame] | 102 | * Skip anonymous pages reclamation. |
| 103 | * |
| 104 | * If this parameter is set as ``Y``, DAMON_RECLAIM does not reclaim anonymous |
| 105 | * pages. By default, ``N``. |
| 106 | */ |
| 107 | static bool skip_anon __read_mostly; |
| 108 | module_param(skip_anon, bool, 0600); |
| 109 | |
| 110 | /* |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 111 | * PID of the DAMON thread |
| 112 | * |
| 113 | * If DAMON_RECLAIM is enabled, this becomes the PID of the worker thread. |
| 114 | * Else, -1. |
| 115 | */ |
| 116 | static int kdamond_pid __read_mostly = -1; |
| 117 | module_param(kdamond_pid, int, 0400); |
| 118 | |
SeongJae Park | b71f3ea | 2022-09-13 17:44:43 +0000 | [diff] [blame] | 119 | static struct damos_stat damon_reclaim_stat; |
| 120 | DEFINE_DAMON_MODULES_DAMOS_STATS_PARAMS(damon_reclaim_stat, |
| 121 | reclaim_tried_regions, reclaimed_regions, quota_exceeds); |
SeongJae Park | 60e52e7 | 2022-01-14 14:10:23 -0800 | [diff] [blame] | 122 | |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 123 | static struct damon_ctx *ctx; |
| 124 | static struct damon_target *target; |
| 125 | |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 126 | static struct damos *damon_reclaim_new_scheme(void) |
| 127 | { |
Yajun Deng | f5a79d7 | 2022-09-08 19:14:43 +0000 | [diff] [blame] | 128 | struct damos_access_pattern pattern = { |
| 129 | /* Find regions having PAGE_SIZE or larger size */ |
| 130 | .min_sz_region = PAGE_SIZE, |
| 131 | .max_sz_region = ULONG_MAX, |
| 132 | /* and not accessed at all */ |
| 133 | .min_nr_accesses = 0, |
| 134 | .max_nr_accesses = 0, |
| 135 | /* for min_age or more micro-seconds */ |
SeongJae Park | 8c341ae | 2022-09-13 17:44:34 +0000 | [diff] [blame] | 136 | .min_age_region = min_age / |
| 137 | damon_reclaim_mon_attrs.aggr_interval, |
Yajun Deng | f5a79d7 | 2022-09-08 19:14:43 +0000 | [diff] [blame] | 138 | .max_age_region = UINT_MAX, |
| 139 | }; |
Yajun Deng | f5a79d7 | 2022-09-08 19:14:43 +0000 | [diff] [blame] | 140 | |
| 141 | return damon_new_scheme( |
| 142 | &pattern, |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 143 | /* page out those, as soon as found */ |
| 144 | DAMOS_PAGEOUT, |
| 145 | /* under the quota. */ |
SeongJae Park | a9d57c7 | 2022-09-13 17:44:47 +0000 | [diff] [blame] | 146 | &damon_reclaim_quota, |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 147 | /* (De)activate this according to the watermarks. */ |
SeongJae Park | 34f47ea | 2022-09-13 17:44:41 +0000 | [diff] [blame] | 148 | &damon_reclaim_wmarks); |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 149 | } |
| 150 | |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 151 | static int damon_reclaim_apply_parameters(void) |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 152 | { |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 153 | struct damos *scheme; |
SeongJae Park | 66d9fae | 2022-12-05 23:08:22 +0000 | [diff] [blame] | 154 | struct damos_filter *filter; |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 155 | int err = 0; |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 156 | |
SeongJae Park | 8c341ae | 2022-09-13 17:44:34 +0000 | [diff] [blame] | 157 | err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs); |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 158 | if (err) |
| 159 | return err; |
| 160 | |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 161 | /* Will be freed by next 'damon_set_schemes()' below */ |
| 162 | scheme = damon_reclaim_new_scheme(); |
| 163 | if (!scheme) |
| 164 | return -ENOMEM; |
SeongJae Park | 66d9fae | 2022-12-05 23:08:22 +0000 | [diff] [blame] | 165 | if (skip_anon) { |
| 166 | filter = damos_new_filter(DAMOS_FILTER_TYPE_ANON, true); |
| 167 | if (!filter) { |
| 168 | /* Will be freed by next 'damon_set_schemes()' below */ |
| 169 | damon_destroy_scheme(scheme); |
| 170 | return -ENOMEM; |
| 171 | } |
| 172 | damos_add_filter(scheme, filter); |
| 173 | } |
Kaixu Xia | cc71352 | 2022-09-16 23:20:35 +0800 | [diff] [blame] | 174 | damon_set_schemes(ctx, &scheme, 1); |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 175 | |
Kaixu Xia | 233f0b3 | 2022-09-20 16:53:22 +0000 | [diff] [blame] | 176 | return damon_set_region_biggest_system_ram_default(target, |
| 177 | &monitor_region_start, |
| 178 | &monitor_region_end); |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 179 | } |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 180 | |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 181 | static int damon_reclaim_turn(bool on) |
| 182 | { |
| 183 | int err; |
| 184 | |
| 185 | if (!on) { |
| 186 | err = damon_stop(&ctx, 1); |
| 187 | if (!err) |
| 188 | kdamond_pid = -1; |
| 189 | return err; |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 190 | } |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 191 | |
| 192 | err = damon_reclaim_apply_parameters(); |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 193 | if (err) |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 194 | return err; |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 195 | |
SeongJae Park | 8b9b0d3 | 2022-03-22 14:49:21 -0700 | [diff] [blame] | 196 | err = damon_start(&ctx, 1, true); |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 197 | if (err) |
| 198 | return err; |
| 199 | kdamond_pid = ctx->kdamond->pid; |
| 200 | return 0; |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 201 | } |
| 202 | |
SeongJae Park | d79905c | 2022-06-06 18:23:10 +0000 | [diff] [blame] | 203 | static int damon_reclaim_enabled_store(const char *val, |
Hailong Tu | 059342d | 2022-04-29 14:37:00 -0700 | [diff] [blame] | 204 | const struct kernel_param *kp) |
| 205 | { |
SeongJae Park | 04e9876 | 2022-10-25 17:36:47 +0000 | [diff] [blame] | 206 | bool is_enabled = enabled; |
| 207 | bool enable; |
| 208 | int err; |
Hailong Tu | 059342d | 2022-04-29 14:37:00 -0700 | [diff] [blame] | 209 | |
Christophe JAILLET | e6aff38 | 2022-11-01 22:14:08 +0100 | [diff] [blame] | 210 | err = kstrtobool(val, &enable); |
SeongJae Park | 04e9876 | 2022-10-25 17:36:47 +0000 | [diff] [blame] | 211 | if (err) |
| 212 | return err; |
Hailong Tu | 059342d | 2022-04-29 14:37:00 -0700 | [diff] [blame] | 213 | |
SeongJae Park | 04e9876 | 2022-10-25 17:36:47 +0000 | [diff] [blame] | 214 | if (is_enabled == enable) |
| 215 | return 0; |
SeongJae Park | 2949282 | 2022-06-04 19:50:51 +0000 | [diff] [blame] | 216 | |
SeongJae Park | 04e9876 | 2022-10-25 17:36:47 +0000 | [diff] [blame] | 217 | /* Called before init function. The function will handle this. */ |
| 218 | if (!ctx) |
| 219 | goto set_param_out; |
| 220 | |
| 221 | err = damon_reclaim_turn(enable); |
| 222 | if (err) |
| 223 | return err; |
| 224 | |
| 225 | set_param_out: |
| 226 | enabled = enable; |
| 227 | return err; |
Hailong Tu | 059342d | 2022-04-29 14:37:00 -0700 | [diff] [blame] | 228 | } |
| 229 | |
| 230 | static const struct kernel_param_ops enabled_param_ops = { |
SeongJae Park | d79905c | 2022-06-06 18:23:10 +0000 | [diff] [blame] | 231 | .set = damon_reclaim_enabled_store, |
Hailong Tu | 059342d | 2022-04-29 14:37:00 -0700 | [diff] [blame] | 232 | .get = param_get_bool, |
| 233 | }; |
| 234 | |
| 235 | module_param_cb(enabled, &enabled_param_ops, &enabled, 0600); |
| 236 | MODULE_PARM_DESC(enabled, |
| 237 | "Enable or disable DAMON_RECLAIM (default: disabled)"); |
| 238 | |
SeongJae Park | f25ab3b | 2022-06-06 18:23:07 +0000 | [diff] [blame] | 239 | static int damon_reclaim_handle_commit_inputs(void) |
| 240 | { |
| 241 | int err; |
| 242 | |
| 243 | if (!commit_inputs) |
| 244 | return 0; |
| 245 | |
| 246 | err = damon_reclaim_apply_parameters(); |
| 247 | commit_inputs = false; |
| 248 | return err; |
| 249 | } |
| 250 | |
SeongJae Park | 60e52e7 | 2022-01-14 14:10:23 -0800 | [diff] [blame] | 251 | static int damon_reclaim_after_aggregation(struct damon_ctx *c) |
| 252 | { |
| 253 | struct damos *s; |
| 254 | |
| 255 | /* update the stats parameter */ |
SeongJae Park | b71f3ea | 2022-09-13 17:44:43 +0000 | [diff] [blame] | 256 | damon_for_each_scheme(s, c) |
| 257 | damon_reclaim_stat = s->stat; |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 258 | |
SeongJae Park | f25ab3b | 2022-06-06 18:23:07 +0000 | [diff] [blame] | 259 | return damon_reclaim_handle_commit_inputs(); |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 260 | } |
| 261 | |
| 262 | static int damon_reclaim_after_wmarks_check(struct damon_ctx *c) |
| 263 | { |
SeongJae Park | f25ab3b | 2022-06-06 18:23:07 +0000 | [diff] [blame] | 264 | return damon_reclaim_handle_commit_inputs(); |
SeongJae Park | 60e52e7 | 2022-01-14 14:10:23 -0800 | [diff] [blame] | 265 | } |
| 266 | |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 267 | static int __init damon_reclaim_init(void) |
| 268 | { |
SeongJae Park | 7ae2c17 | 2022-10-26 22:59:42 +0000 | [diff] [blame] | 269 | int err = damon_modules_new_paddr_ctx_target(&ctx, &target); |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 270 | |
SeongJae Park | 7ae2c17 | 2022-10-26 22:59:42 +0000 | [diff] [blame] | 271 | if (err) |
| 272 | return err; |
SeongJae Park | 4d69c34 | 2022-03-22 14:48:55 -0700 | [diff] [blame] | 273 | |
SeongJae Park | e035c28 | 2022-05-09 18:20:56 -0700 | [diff] [blame] | 274 | ctx->callback.after_wmarks_check = damon_reclaim_after_wmarks_check; |
SeongJae Park | 60e52e7 | 2022-01-14 14:10:23 -0800 | [diff] [blame] | 275 | ctx->callback.after_aggregation = damon_reclaim_after_aggregation; |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 276 | |
SeongJae Park | 04e9876 | 2022-10-25 17:36:47 +0000 | [diff] [blame] | 277 | /* 'enabled' has set before this function, probably via command line */ |
| 278 | if (enabled) |
| 279 | err = damon_reclaim_turn(true); |
SeongJae Park | 2949282 | 2022-06-04 19:50:51 +0000 | [diff] [blame] | 280 | |
SeongJae Park | 04e9876 | 2022-10-25 17:36:47 +0000 | [diff] [blame] | 281 | return err; |
SeongJae Park | 43b0536 | 2021-11-05 13:47:57 -0700 | [diff] [blame] | 282 | } |
| 283 | |
| 284 | module_init(damon_reclaim_init); |