tree: https://github.com/kdave/btrfs-devel.git misc-next head: e6c69fcbee7ef1d7bde4ff78eb1377dbe09d71cf commit: e6c69fcbee7ef1d7bde4ff78eb1377dbe09d71cf [68/68] btrfs: defrag: use control structure in btrfs_defrag_file() config: arm64-randconfig-r036-20220214 (https://download.01.org/0day-ci/archive/20220216/202202160409.lvaZWYmg-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 37f422f4ac31c8b8041c6b62065263314282dab6) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/kdave/btrfs-devel/commit/e6c69fcbee7ef1d7bde4ff78eb1377dbe09d71cf git remote add kdave-btrfs-devel https://github.com/kdave/btrfs-devel.git git fetch --no-tags kdave-btrfs-devel misc-next git checkout e6c69fcbee7ef1d7bde4ff78eb1377dbe09d71cf # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/mfd/ fs/btrfs/ mm/kasan/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> fs/btrfs/ioctl.c:1192: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Collect all valid target extents. fs/btrfs/ioctl.c:1598: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Entry point to file defragmentation. vim +1192 fs/btrfs/ioctl.c 4cb5300bc839b8a Chris Mason 2011-05-24 1190 e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1191 /** eb793cf857828db Qu Wenruo 2021-08-06 @1192 * Collect all valid target extents. eb793cf857828db Qu Wenruo 2021-08-06 1193 * e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1194 * @inode: inode to defragment e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1195 * @ctrl: extra defrag policy control eb793cf857828db Qu Wenruo 2021-08-06 1196 * @start: file offset to lookup eb793cf857828db Qu Wenruo 2021-08-06 1197 * @len: length to lookup e9eec72151e215c Qu Wenruo 2021-08-06 1198 * @locked: if the range has already held extent lock eb793cf857828db Qu Wenruo 2021-08-06 1199 * @target_list: list of targets file extents e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1200 * e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1201 * Will update ctrl::last_scanned. 4cb5300bc839b8a Chris Mason 2011-05-24 1202 */ eb793cf857828db Qu Wenruo 2021-08-06 1203 static int defrag_collect_targets(struct btrfs_inode *inode, e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1204 struct btrfs_defrag_ctrl *ctrl, e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1205 u64 start, u32 len, e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1206 bool locked, struct list_head *target_list) eb793cf857828db Qu Wenruo 2021-08-06 1207 { e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1208 bool do_compress = (ctrl->flags & BTRFS_DEFRAG_RANGE_COMPRESS); c0a67d1ead1393b Qu Wenruo 2022-02-11 1209 bool last_is_target = false; eb793cf857828db Qu Wenruo 2021-08-06 1210 u64 cur = start; eb793cf857828db Qu Wenruo 2021-08-06 1211 int ret = 0; 4cb5300bc839b8a Chris Mason 2011-05-24 1212 eb793cf857828db Qu Wenruo 2021-08-06 1213 while (cur < start + len) { eb793cf857828db Qu Wenruo 2021-08-06 1214 struct extent_map *em; eb793cf857828db Qu Wenruo 2021-08-06 1215 struct defrag_target_range *new; eb793cf857828db Qu Wenruo 2021-08-06 1216 bool next_mergeable = true; eb793cf857828db Qu Wenruo 2021-08-06 1217 u64 range_len; eb793cf857828db Qu Wenruo 2021-08-06 1218 c0a67d1ead1393b Qu Wenruo 2022-02-11 1219 last_is_target = false; e9eec72151e215c Qu Wenruo 2021-08-06 1220 em = defrag_lookup_extent(&inode->vfs_inode, cur, locked); eb793cf857828db Qu Wenruo 2021-08-06 1221 if (!em) eb793cf857828db Qu Wenruo 2021-08-06 1222 break; eb793cf857828db Qu Wenruo 2021-08-06 1223 eb793cf857828db Qu Wenruo 2021-08-06 1224 /* Skip hole/inline/preallocated extents */ eb793cf857828db Qu Wenruo 2021-08-06 1225 if (em->block_start >= EXTENT_MAP_LAST_BYTE || eb793cf857828db Qu Wenruo 2021-08-06 1226 test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) eb793cf857828db Qu Wenruo 2021-08-06 1227 goto next; 4cb5300bc839b8a Chris Mason 2011-05-24 1228 eb793cf857828db Qu Wenruo 2021-08-06 1229 /* Skip older extent */ e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1230 if (em->generation < ctrl->newer_than) eb793cf857828db Qu Wenruo 2021-08-06 1231 goto next; 7f458a3873ae94e Filipe Manana 2020-11-04 1232 79c19b4d71f61a3 Qu Wenruo 2022-02-08 1233 /* This em is under writeback, no need to defrag */ 79c19b4d71f61a3 Qu Wenruo 2022-02-08 1234 if (em->generation == (u64)-1) 79c19b4d71f61a3 Qu Wenruo 2022-02-08 1235 goto next; 79c19b4d71f61a3 Qu Wenruo 2022-02-08 1236 0cb5950f3f3b51a Filipe Manana 2022-01-20 1237 /* 0cb5950f3f3b51a Filipe Manana 2022-01-20 1238 * Our start offset might be in the middle of an existing extent 0cb5950f3f3b51a Filipe Manana 2022-01-20 1239 * map, so take that into account. 0cb5950f3f3b51a Filipe Manana 2022-01-20 1240 */ 0cb5950f3f3b51a Filipe Manana 2022-01-20 1241 range_len = em->len - (cur - em->start); 0cb5950f3f3b51a Filipe Manana 2022-01-20 1242 /* 0cb5950f3f3b51a Filipe Manana 2022-01-20 1243 * If this range of the extent map is already flagged for delalloc, 0cb5950f3f3b51a Filipe Manana 2022-01-20 1244 * skip it, because: 0cb5950f3f3b51a Filipe Manana 2022-01-20 1245 * 0cb5950f3f3b51a Filipe Manana 2022-01-20 1246 * 1) We could deadlock later, when trying to reserve space for 0cb5950f3f3b51a Filipe Manana 2022-01-20 1247 * delalloc, because in case we can't immediately reserve space 0cb5950f3f3b51a Filipe Manana 2022-01-20 1248 * the flusher can start delalloc and wait for the respective 0cb5950f3f3b51a Filipe Manana 2022-01-20 1249 * ordered extents to complete. The deadlock would happen 0cb5950f3f3b51a Filipe Manana 2022-01-20 1250 * because we do the space reservation while holding the range 0cb5950f3f3b51a Filipe Manana 2022-01-20 1251 * locked, and starting writeback, or finishing an ordered 0cb5950f3f3b51a Filipe Manana 2022-01-20 1252 * extent, requires locking the range; 0cb5950f3f3b51a Filipe Manana 2022-01-20 1253 * 0cb5950f3f3b51a Filipe Manana 2022-01-20 1254 * 2) If there's delalloc there, it means there's dirty pages for 0cb5950f3f3b51a Filipe Manana 2022-01-20 1255 * which writeback has not started yet (we clean the delalloc 0cb5950f3f3b51a Filipe Manana 2022-01-20 1256 * flag when starting writeback and after creating an ordered 0cb5950f3f3b51a Filipe Manana 2022-01-20 1257 * extent). If we mark pages in an adjacent range for defrag, 0cb5950f3f3b51a Filipe Manana 2022-01-20 1258 * then we will have a larger contiguous range for delalloc, 0cb5950f3f3b51a Filipe Manana 2022-01-20 1259 * very likely resulting in a larger extent after writeback is 0cb5950f3f3b51a Filipe Manana 2022-01-20 1260 * triggered (except in a case of free space fragmentation). 0cb5950f3f3b51a Filipe Manana 2022-01-20 1261 */ 0cb5950f3f3b51a Filipe Manana 2022-01-20 1262 if (test_range_bit(&inode->io_tree, cur, cur + range_len - 1, 0cb5950f3f3b51a Filipe Manana 2022-01-20 1263 EXTENT_DELALLOC, 0, NULL)) 0cb5950f3f3b51a Filipe Manana 2022-01-20 1264 goto next; 0cb5950f3f3b51a Filipe Manana 2022-01-20 1265 7f458a3873ae94e Filipe Manana 2020-11-04 1266 /* eb793cf857828db Qu Wenruo 2021-08-06 1267 * For do_compress case, we want to compress all valid file eb793cf857828db Qu Wenruo 2021-08-06 1268 * extents, thus no @extent_thresh or mergeable check. 7f458a3873ae94e Filipe Manana 2020-11-04 1269 */ eb793cf857828db Qu Wenruo 2021-08-06 1270 if (do_compress) eb793cf857828db Qu Wenruo 2021-08-06 1271 goto add; eb793cf857828db Qu Wenruo 2021-08-06 1272 eb793cf857828db Qu Wenruo 2021-08-06 1273 /* Skip too large extent */ e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1274 if (range_len >= ctrl->extent_thresh) eb793cf857828db Qu Wenruo 2021-08-06 1275 goto next; eb793cf857828db Qu Wenruo 2021-08-06 1276 c55eaee8366f0b9 Qu Wenruo 2022-01-28 1277 /* c55eaee8366f0b9 Qu Wenruo 2022-01-28 1278 * Skip extents already at its max capacity, this is mostly for c55eaee8366f0b9 Qu Wenruo 2022-01-28 1279 * compressed extents, which max cap is only 128K. c55eaee8366f0b9 Qu Wenruo 2022-01-28 1280 */ c55eaee8366f0b9 Qu Wenruo 2022-01-28 1281 if (em->len >= get_extent_max_capacity(em)) c55eaee8366f0b9 Qu Wenruo 2022-01-28 1282 goto next; c55eaee8366f0b9 Qu Wenruo 2022-01-28 1283 e9eec72151e215c Qu Wenruo 2021-08-06 1284 next_mergeable = defrag_check_next_extent(&inode->vfs_inode, em, e9eec72151e215c Qu Wenruo 2021-08-06 1285 locked); eb793cf857828db Qu Wenruo 2021-08-06 1286 if (!next_mergeable) { eb793cf857828db Qu Wenruo 2021-08-06 1287 struct defrag_target_range *last; eb793cf857828db Qu Wenruo 2021-08-06 1288 eb793cf857828db Qu Wenruo 2021-08-06 1289 /* Empty target list, no way to merge with last entry */ eb793cf857828db Qu Wenruo 2021-08-06 1290 if (list_empty(target_list)) eb793cf857828db Qu Wenruo 2021-08-06 1291 goto next; eb793cf857828db Qu Wenruo 2021-08-06 1292 last = list_entry(target_list->prev, eb793cf857828db Qu Wenruo 2021-08-06 1293 struct defrag_target_range, list); eb793cf857828db Qu Wenruo 2021-08-06 1294 /* Not mergeable with last entry */ eb793cf857828db Qu Wenruo 2021-08-06 1295 if (last->start + last->len != cur) eb793cf857828db Qu Wenruo 2021-08-06 1296 goto next; 7f458a3873ae94e Filipe Manana 2020-11-04 1297 eb793cf857828db Qu Wenruo 2021-08-06 1298 /* Mergeable, fall through to add it to @target_list. */ 7f458a3873ae94e Filipe Manana 2020-11-04 1299 } eb793cf857828db Qu Wenruo 2021-08-06 1300 eb793cf857828db Qu Wenruo 2021-08-06 1301 add: c0a67d1ead1393b Qu Wenruo 2022-02-11 1302 last_is_target = true; eb793cf857828db Qu Wenruo 2021-08-06 1303 range_len = min(extent_map_end(em), start + len) - cur; eb793cf857828db Qu Wenruo 2021-08-06 1304 /* eb793cf857828db Qu Wenruo 2021-08-06 1305 * This one is a good target, check if it can be merged into eb793cf857828db Qu Wenruo 2021-08-06 1306 * last range of the target list. eb793cf857828db Qu Wenruo 2021-08-06 1307 */ eb793cf857828db Qu Wenruo 2021-08-06 1308 if (!list_empty(target_list)) { eb793cf857828db Qu Wenruo 2021-08-06 1309 struct defrag_target_range *last; eb793cf857828db Qu Wenruo 2021-08-06 1310 eb793cf857828db Qu Wenruo 2021-08-06 1311 last = list_entry(target_list->prev, eb793cf857828db Qu Wenruo 2021-08-06 1312 struct defrag_target_range, list); eb793cf857828db Qu Wenruo 2021-08-06 1313 ASSERT(last->start + last->len <= cur); eb793cf857828db Qu Wenruo 2021-08-06 1314 if (last->start + last->len == cur) { eb793cf857828db Qu Wenruo 2021-08-06 1315 /* Mergeable, enlarge the last entry */ eb793cf857828db Qu Wenruo 2021-08-06 1316 last->len += range_len; eb793cf857828db Qu Wenruo 2021-08-06 1317 goto next; 7f458a3873ae94e Filipe Manana 2020-11-04 1318 } eb793cf857828db Qu Wenruo 2021-08-06 1319 /* Fall through to allocate a new entry */ eb793cf857828db Qu Wenruo 2021-08-06 1320 } eb793cf857828db Qu Wenruo 2021-08-06 1321 eb793cf857828db Qu Wenruo 2021-08-06 1322 /* Allocate new defrag_target_range */ eb793cf857828db Qu Wenruo 2021-08-06 1323 new = kmalloc(sizeof(*new), GFP_NOFS); eb793cf857828db Qu Wenruo 2021-08-06 1324 if (!new) { 7f458a3873ae94e Filipe Manana 2020-11-04 1325 free_extent_map(em); eb793cf857828db Qu Wenruo 2021-08-06 1326 ret = -ENOMEM; eb793cf857828db Qu Wenruo 2021-08-06 1327 break; 7f458a3873ae94e Filipe Manana 2020-11-04 1328 } eb793cf857828db Qu Wenruo 2021-08-06 1329 new->start = cur; eb793cf857828db Qu Wenruo 2021-08-06 1330 new->len = range_len; eb793cf857828db Qu Wenruo 2021-08-06 1331 list_add_tail(&new->list, target_list); 7f458a3873ae94e Filipe Manana 2020-11-04 1332 eb793cf857828db Qu Wenruo 2021-08-06 1333 next: eb793cf857828db Qu Wenruo 2021-08-06 1334 cur = extent_map_end(em); eb793cf857828db Qu Wenruo 2021-08-06 1335 free_extent_map(em); eb793cf857828db Qu Wenruo 2021-08-06 1336 } eb793cf857828db Qu Wenruo 2021-08-06 1337 if (ret < 0) { eb793cf857828db Qu Wenruo 2021-08-06 1338 struct defrag_target_range *entry; eb793cf857828db Qu Wenruo 2021-08-06 1339 struct defrag_target_range *tmp; 4cb5300bc839b8a Chris Mason 2011-05-24 1340 eb793cf857828db Qu Wenruo 2021-08-06 1341 list_for_each_entry_safe(entry, tmp, target_list, list) { eb793cf857828db Qu Wenruo 2021-08-06 1342 list_del_init(&entry->list); eb793cf857828db Qu Wenruo 2021-08-06 1343 kfree(entry); eb793cf857828db Qu Wenruo 2021-08-06 1344 } eb793cf857828db Qu Wenruo 2021-08-06 1345 } e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1346 if (!ret) { c0a67d1ead1393b Qu Wenruo 2022-02-11 1347 /* c0a67d1ead1393b Qu Wenruo 2022-02-11 1348 * If the last extent is not a target, the caller can skip to c0a67d1ead1393b Qu Wenruo 2022-02-11 1349 * the end of that extent. c0a67d1ead1393b Qu Wenruo 2022-02-11 1350 * Otherwise, we can only go the end of the specified range. e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1351 * e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1352 * And we may got a range smaller than current e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1353 * ctrl->last_scanned (e.g. executed in the defrag_one_range e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1354 * call), so we have to ensure we didn't decrease e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1355 * ctrl->last_scanned. c0a67d1ead1393b Qu Wenruo 2022-02-11 1356 */ c0a67d1ead1393b Qu Wenruo 2022-02-11 1357 if (!last_is_target) e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1358 ctrl->last_scanned = max(cur, ctrl->last_scanned); c0a67d1ead1393b Qu Wenruo 2022-02-11 1359 else e6c69fcbee7ef1d Qu Wenruo 2022-02-11 1360 ctrl->last_scanned = max(start + len, ctrl->last_scanned); c0a67d1ead1393b Qu Wenruo 2022-02-11 1361 } eb793cf857828db Qu Wenruo 2021-08-06 1362 return ret; 4cb5300bc839b8a Chris Mason 2011-05-24 1363 } 4cb5300bc839b8a Chris Mason 2011-05-24 1364 :::::: The code at line 1192 was first introduced by commit :::::: eb793cf857828dbb1f21bfe405e5e493fdceae6c btrfs: defrag: introduce helper to collect target file extents :::::: TO: Qu Wenruo <wqu@xxxxxxxx> :::::: CC: David Sterba <dsterba@xxxxxxxx> --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
