debug.c 15 KB

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  1. /*
  2. * f2fs debugging statistics
  3. *
  4. * Copyright (c) 2012 Samsung Electronics Co., Ltd.
  5. * http://www.samsung.com/
  6. * Copyright (c) 2012 Linux Foundation
  7. * Copyright (c) 2012 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  8. *
  9. * This program is free software; you can redistribute it and/or modify
  10. * it under the terms of the GNU General Public License version 2 as
  11. * published by the Free Software Foundation.
  12. */
  13. #include <linux/fs.h>
  14. #include <linux/backing-dev.h>
  15. #include <linux/f2fs_fs.h>
  16. #include <linux/blkdev.h>
  17. #include <linux/debugfs.h>
  18. #include <linux/seq_file.h>
  19. #include "f2fs.h"
  20. #include "node.h"
  21. #include "segment.h"
  22. #include "gc.h"
  23. static LIST_HEAD(f2fs_stat_list);
  24. static struct dentry *f2fs_debugfs_root;
  25. static DEFINE_MUTEX(f2fs_stat_mutex);
  26. static void update_general_status(struct f2fs_sb_info *sbi)
  27. {
  28. struct f2fs_stat_info *si = F2FS_STAT(sbi);
  29. int i;
  30. /* validation check of the segment numbers */
  31. si->hit_largest = atomic64_read(&sbi->read_hit_largest);
  32. si->hit_cached = atomic64_read(&sbi->read_hit_cached);
  33. si->hit_rbtree = atomic64_read(&sbi->read_hit_rbtree);
  34. si->hit_total = si->hit_largest + si->hit_cached + si->hit_rbtree;
  35. si->total_ext = atomic64_read(&sbi->total_hit_ext);
  36. si->ext_tree = atomic_read(&sbi->total_ext_tree);
  37. si->zombie_tree = atomic_read(&sbi->total_zombie_tree);
  38. si->ext_node = atomic_read(&sbi->total_ext_node);
  39. si->ndirty_node = get_pages(sbi, F2FS_DIRTY_NODES);
  40. si->ndirty_dent = get_pages(sbi, F2FS_DIRTY_DENTS);
  41. si->ndirty_meta = get_pages(sbi, F2FS_DIRTY_META);
  42. si->ndirty_data = get_pages(sbi, F2FS_DIRTY_DATA);
  43. si->ndirty_imeta = get_pages(sbi, F2FS_DIRTY_IMETA);
  44. si->ndirty_dirs = sbi->ndirty_inode[DIR_INODE];
  45. si->ndirty_files = sbi->ndirty_inode[FILE_INODE];
  46. si->ndirty_all = sbi->ndirty_inode[DIRTY_META];
  47. si->inmem_pages = get_pages(sbi, F2FS_INMEM_PAGES);
  48. si->aw_cnt = atomic_read(&sbi->aw_cnt);
  49. si->max_aw_cnt = atomic_read(&sbi->max_aw_cnt);
  50. si->nr_wb_cp_data = get_pages(sbi, F2FS_WB_CP_DATA);
  51. si->nr_wb_data = get_pages(sbi, F2FS_WB_DATA);
  52. si->total_count = (int)sbi->user_block_count / sbi->blocks_per_seg;
  53. si->rsvd_segs = reserved_segments(sbi);
  54. si->overp_segs = overprovision_segments(sbi);
  55. si->valid_count = valid_user_blocks(sbi);
  56. si->discard_blks = discard_blocks(sbi);
  57. si->valid_node_count = valid_node_count(sbi);
  58. si->valid_inode_count = valid_inode_count(sbi);
  59. si->inline_xattr = atomic_read(&sbi->inline_xattr);
  60. si->inline_inode = atomic_read(&sbi->inline_inode);
  61. si->inline_dir = atomic_read(&sbi->inline_dir);
  62. si->orphans = sbi->im[ORPHAN_INO].ino_num;
  63. si->utilization = utilization(sbi);
  64. si->free_segs = free_segments(sbi);
  65. si->free_secs = free_sections(sbi);
  66. si->prefree_count = prefree_segments(sbi);
  67. si->dirty_count = dirty_segments(sbi);
  68. si->node_pages = NODE_MAPPING(sbi)->nrpages;
  69. si->meta_pages = META_MAPPING(sbi)->nrpages;
  70. si->nats = NM_I(sbi)->nat_cnt;
  71. si->dirty_nats = NM_I(sbi)->dirty_nat_cnt;
  72. si->sits = MAIN_SEGS(sbi);
  73. si->dirty_sits = SIT_I(sbi)->dirty_sentries;
  74. si->free_nids = NM_I(sbi)->nid_cnt[FREE_NID_LIST];
  75. si->alloc_nids = NM_I(sbi)->nid_cnt[ALLOC_NID_LIST];
  76. si->bg_gc = sbi->bg_gc;
  77. si->util_free = (int)(free_user_blocks(sbi) >> sbi->log_blocks_per_seg)
  78. * 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
  79. / 2;
  80. si->util_valid = (int)(written_block_count(sbi) >>
  81. sbi->log_blocks_per_seg)
  82. * 100 / (int)(sbi->user_block_count >> sbi->log_blocks_per_seg)
  83. / 2;
  84. si->util_invalid = 50 - si->util_free - si->util_valid;
  85. for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_NODE; i++) {
  86. struct curseg_info *curseg = CURSEG_I(sbi, i);
  87. si->curseg[i] = curseg->segno;
  88. si->cursec[i] = curseg->segno / sbi->segs_per_sec;
  89. si->curzone[i] = si->cursec[i] / sbi->secs_per_zone;
  90. }
  91. for (i = 0; i < 2; i++) {
  92. si->segment_count[i] = sbi->segment_count[i];
  93. si->block_count[i] = sbi->block_count[i];
  94. }
  95. si->inplace_count = atomic_read(&sbi->inplace_count);
  96. }
  97. /*
  98. * This function calculates BDF of every segments
  99. */
  100. static void update_sit_info(struct f2fs_sb_info *sbi)
  101. {
  102. struct f2fs_stat_info *si = F2FS_STAT(sbi);
  103. unsigned long long blks_per_sec, hblks_per_sec, total_vblocks;
  104. unsigned long long bimodal, dist;
  105. unsigned int segno, vblocks;
  106. int ndirty = 0;
  107. bimodal = 0;
  108. total_vblocks = 0;
  109. blks_per_sec = sbi->segs_per_sec * sbi->blocks_per_seg;
  110. hblks_per_sec = blks_per_sec / 2;
  111. for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
  112. vblocks = get_valid_blocks(sbi, segno, sbi->segs_per_sec);
  113. dist = abs(vblocks - hblks_per_sec);
  114. bimodal += dist * dist;
  115. if (vblocks > 0 && vblocks < blks_per_sec) {
  116. total_vblocks += vblocks;
  117. ndirty++;
  118. }
  119. }
  120. dist = div_u64(MAIN_SECS(sbi) * hblks_per_sec * hblks_per_sec, 100);
  121. si->bimodal = div64_u64(bimodal, dist);
  122. if (si->dirty_count)
  123. si->avg_vblocks = div_u64(total_vblocks, ndirty);
  124. else
  125. si->avg_vblocks = 0;
  126. }
  127. /*
  128. * This function calculates memory footprint.
  129. */
  130. static void update_mem_info(struct f2fs_sb_info *sbi)
  131. {
  132. struct f2fs_stat_info *si = F2FS_STAT(sbi);
  133. unsigned npages;
  134. int i;
  135. if (si->base_mem)
  136. goto get_cache;
  137. si->base_mem = sizeof(struct f2fs_sb_info) + sbi->sb->s_blocksize;
  138. si->base_mem += 2 * sizeof(struct f2fs_inode_info);
  139. si->base_mem += sizeof(*sbi->ckpt);
  140. si->base_mem += sizeof(struct percpu_counter) * NR_COUNT_TYPE;
  141. /* build sm */
  142. si->base_mem += sizeof(struct f2fs_sm_info);
  143. /* build sit */
  144. si->base_mem += sizeof(struct sit_info);
  145. si->base_mem += MAIN_SEGS(sbi) * sizeof(struct seg_entry);
  146. si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
  147. si->base_mem += 2 * SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
  148. if (f2fs_discard_en(sbi))
  149. si->base_mem += SIT_VBLOCK_MAP_SIZE * MAIN_SEGS(sbi);
  150. si->base_mem += SIT_VBLOCK_MAP_SIZE;
  151. if (sbi->segs_per_sec > 1)
  152. si->base_mem += MAIN_SECS(sbi) * sizeof(struct sec_entry);
  153. si->base_mem += __bitmap_size(sbi, SIT_BITMAP);
  154. /* build free segmap */
  155. si->base_mem += sizeof(struct free_segmap_info);
  156. si->base_mem += f2fs_bitmap_size(MAIN_SEGS(sbi));
  157. si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
  158. /* build curseg */
  159. si->base_mem += sizeof(struct curseg_info) * NR_CURSEG_TYPE;
  160. si->base_mem += PAGE_SIZE * NR_CURSEG_TYPE;
  161. /* build dirty segmap */
  162. si->base_mem += sizeof(struct dirty_seglist_info);
  163. si->base_mem += NR_DIRTY_TYPE * f2fs_bitmap_size(MAIN_SEGS(sbi));
  164. si->base_mem += f2fs_bitmap_size(MAIN_SECS(sbi));
  165. /* build nm */
  166. si->base_mem += sizeof(struct f2fs_nm_info);
  167. si->base_mem += __bitmap_size(sbi, NAT_BITMAP);
  168. get_cache:
  169. si->cache_mem = 0;
  170. /* build gc */
  171. if (sbi->gc_thread)
  172. si->cache_mem += sizeof(struct f2fs_gc_kthread);
  173. /* build merge flush thread */
  174. if (SM_I(sbi)->fcc_info)
  175. si->cache_mem += sizeof(struct flush_cmd_control);
  176. if (SM_I(sbi)->dcc_info)
  177. si->cache_mem += sizeof(struct discard_cmd_control);
  178. /* free nids */
  179. si->cache_mem += (NM_I(sbi)->nid_cnt[FREE_NID_LIST] +
  180. NM_I(sbi)->nid_cnt[ALLOC_NID_LIST]) *
  181. sizeof(struct free_nid);
  182. si->cache_mem += NM_I(sbi)->nat_cnt * sizeof(struct nat_entry);
  183. si->cache_mem += NM_I(sbi)->dirty_nat_cnt *
  184. sizeof(struct nat_entry_set);
  185. si->cache_mem += si->inmem_pages * sizeof(struct inmem_pages);
  186. for (i = 0; i <= ORPHAN_INO; i++)
  187. si->cache_mem += sbi->im[i].ino_num * sizeof(struct ino_entry);
  188. si->cache_mem += atomic_read(&sbi->total_ext_tree) *
  189. sizeof(struct extent_tree);
  190. si->cache_mem += atomic_read(&sbi->total_ext_node) *
  191. sizeof(struct extent_node);
  192. si->page_mem = 0;
  193. npages = NODE_MAPPING(sbi)->nrpages;
  194. si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
  195. npages = META_MAPPING(sbi)->nrpages;
  196. si->page_mem += (unsigned long long)npages << PAGE_SHIFT;
  197. }
  198. static int stat_show(struct seq_file *s, void *v)
  199. {
  200. struct f2fs_stat_info *si;
  201. int i = 0;
  202. int j;
  203. mutex_lock(&f2fs_stat_mutex);
  204. list_for_each_entry(si, &f2fs_stat_list, stat_list) {
  205. update_general_status(si->sbi);
  206. seq_printf(s, "\n=====[ partition info(%pg). #%d, %s]=====\n",
  207. si->sbi->sb->s_bdev, i++,
  208. f2fs_readonly(si->sbi->sb) ? "RO": "RW");
  209. seq_printf(s, "[SB: 1] [CP: 2] [SIT: %d] [NAT: %d] ",
  210. si->sit_area_segs, si->nat_area_segs);
  211. seq_printf(s, "[SSA: %d] [MAIN: %d",
  212. si->ssa_area_segs, si->main_area_segs);
  213. seq_printf(s, "(OverProv:%d Resv:%d)]\n\n",
  214. si->overp_segs, si->rsvd_segs);
  215. if (test_opt(si->sbi, DISCARD))
  216. seq_printf(s, "Utilization: %u%% (%u valid blocks, %u discard blocks)\n",
  217. si->utilization, si->valid_count, si->discard_blks);
  218. else
  219. seq_printf(s, "Utilization: %u%% (%u valid blocks)\n",
  220. si->utilization, si->valid_count);
  221. seq_printf(s, " - Node: %u (Inode: %u, ",
  222. si->valid_node_count, si->valid_inode_count);
  223. seq_printf(s, "Other: %u)\n - Data: %u\n",
  224. si->valid_node_count - si->valid_inode_count,
  225. si->valid_count - si->valid_node_count);
  226. seq_printf(s, " - Inline_xattr Inode: %u\n",
  227. si->inline_xattr);
  228. seq_printf(s, " - Inline_data Inode: %u\n",
  229. si->inline_inode);
  230. seq_printf(s, " - Inline_dentry Inode: %u\n",
  231. si->inline_dir);
  232. seq_printf(s, " - Orphan Inode: %u\n",
  233. si->orphans);
  234. seq_printf(s, "\nMain area: %d segs, %d secs %d zones\n",
  235. si->main_area_segs, si->main_area_sections,
  236. si->main_area_zones);
  237. seq_printf(s, " - COLD data: %d, %d, %d\n",
  238. si->curseg[CURSEG_COLD_DATA],
  239. si->cursec[CURSEG_COLD_DATA],
  240. si->curzone[CURSEG_COLD_DATA]);
  241. seq_printf(s, " - WARM data: %d, %d, %d\n",
  242. si->curseg[CURSEG_WARM_DATA],
  243. si->cursec[CURSEG_WARM_DATA],
  244. si->curzone[CURSEG_WARM_DATA]);
  245. seq_printf(s, " - HOT data: %d, %d, %d\n",
  246. si->curseg[CURSEG_HOT_DATA],
  247. si->cursec[CURSEG_HOT_DATA],
  248. si->curzone[CURSEG_HOT_DATA]);
  249. seq_printf(s, " - Dir dnode: %d, %d, %d\n",
  250. si->curseg[CURSEG_HOT_NODE],
  251. si->cursec[CURSEG_HOT_NODE],
  252. si->curzone[CURSEG_HOT_NODE]);
  253. seq_printf(s, " - File dnode: %d, %d, %d\n",
  254. si->curseg[CURSEG_WARM_NODE],
  255. si->cursec[CURSEG_WARM_NODE],
  256. si->curzone[CURSEG_WARM_NODE]);
  257. seq_printf(s, " - Indir nodes: %d, %d, %d\n",
  258. si->curseg[CURSEG_COLD_NODE],
  259. si->cursec[CURSEG_COLD_NODE],
  260. si->curzone[CURSEG_COLD_NODE]);
  261. seq_printf(s, "\n - Valid: %d\n - Dirty: %d\n",
  262. si->main_area_segs - si->dirty_count -
  263. si->prefree_count - si->free_segs,
  264. si->dirty_count);
  265. seq_printf(s, " - Prefree: %d\n - Free: %d (%d)\n\n",
  266. si->prefree_count, si->free_segs, si->free_secs);
  267. seq_printf(s, "CP calls: %d (BG: %d)\n",
  268. si->cp_count, si->bg_cp_count);
  269. seq_printf(s, "GC calls: %d (BG: %d)\n",
  270. si->call_count, si->bg_gc);
  271. seq_printf(s, " - data segments : %d (%d)\n",
  272. si->data_segs, si->bg_data_segs);
  273. seq_printf(s, " - node segments : %d (%d)\n",
  274. si->node_segs, si->bg_node_segs);
  275. seq_printf(s, "Try to move %d blocks (BG: %d)\n", si->tot_blks,
  276. si->bg_data_blks + si->bg_node_blks);
  277. seq_printf(s, " - data blocks : %d (%d)\n", si->data_blks,
  278. si->bg_data_blks);
  279. seq_printf(s, " - node blocks : %d (%d)\n", si->node_blks,
  280. si->bg_node_blks);
  281. seq_puts(s, "\nExtent Cache:\n");
  282. seq_printf(s, " - Hit Count: L1-1:%llu L1-2:%llu L2:%llu\n",
  283. si->hit_largest, si->hit_cached,
  284. si->hit_rbtree);
  285. seq_printf(s, " - Hit Ratio: %llu%% (%llu / %llu)\n",
  286. !si->total_ext ? 0 :
  287. div64_u64(si->hit_total * 100, si->total_ext),
  288. si->hit_total, si->total_ext);
  289. seq_printf(s, " - Inner Struct Count: tree: %d(%d), node: %d\n",
  290. si->ext_tree, si->zombie_tree, si->ext_node);
  291. seq_puts(s, "\nBalancing F2FS Async:\n");
  292. seq_printf(s, " - IO (CP: %4d, Data: %4d)\n",
  293. si->nr_wb_cp_data, si->nr_wb_data);
  294. seq_printf(s, " - inmem: %4d, atomic IO: %4d (Max. %4d)\n",
  295. si->inmem_pages, si->aw_cnt, si->max_aw_cnt);
  296. seq_printf(s, " - nodes: %4d in %4d\n",
  297. si->ndirty_node, si->node_pages);
  298. seq_printf(s, " - dents: %4d in dirs:%4d (%4d)\n",
  299. si->ndirty_dent, si->ndirty_dirs, si->ndirty_all);
  300. seq_printf(s, " - datas: %4d in files:%4d\n",
  301. si->ndirty_data, si->ndirty_files);
  302. seq_printf(s, " - meta: %4d in %4d\n",
  303. si->ndirty_meta, si->meta_pages);
  304. seq_printf(s, " - imeta: %4d\n",
  305. si->ndirty_imeta);
  306. seq_printf(s, " - NATs: %9d/%9d\n - SITs: %9d/%9d\n",
  307. si->dirty_nats, si->nats, si->dirty_sits, si->sits);
  308. seq_printf(s, " - free_nids: %9d, alloc_nids: %9d\n",
  309. si->free_nids, si->alloc_nids);
  310. seq_puts(s, "\nDistribution of User Blocks:");
  311. seq_puts(s, " [ valid | invalid | free ]\n");
  312. seq_puts(s, " [");
  313. for (j = 0; j < si->util_valid; j++)
  314. seq_putc(s, '-');
  315. seq_putc(s, '|');
  316. for (j = 0; j < si->util_invalid; j++)
  317. seq_putc(s, '-');
  318. seq_putc(s, '|');
  319. for (j = 0; j < si->util_free; j++)
  320. seq_putc(s, '-');
  321. seq_puts(s, "]\n\n");
  322. seq_printf(s, "IPU: %u blocks\n", si->inplace_count);
  323. seq_printf(s, "SSR: %u blocks in %u segments\n",
  324. si->block_count[SSR], si->segment_count[SSR]);
  325. seq_printf(s, "LFS: %u blocks in %u segments\n",
  326. si->block_count[LFS], si->segment_count[LFS]);
  327. /* segment usage info */
  328. update_sit_info(si->sbi);
  329. seq_printf(s, "\nBDF: %u, avg. vblocks: %u\n",
  330. si->bimodal, si->avg_vblocks);
  331. /* memory footprint */
  332. update_mem_info(si->sbi);
  333. seq_printf(s, "\nMemory: %llu KB\n",
  334. (si->base_mem + si->cache_mem + si->page_mem) >> 10);
  335. seq_printf(s, " - static: %llu KB\n",
  336. si->base_mem >> 10);
  337. seq_printf(s, " - cached: %llu KB\n",
  338. si->cache_mem >> 10);
  339. seq_printf(s, " - paged : %llu KB\n",
  340. si->page_mem >> 10);
  341. }
  342. mutex_unlock(&f2fs_stat_mutex);
  343. return 0;
  344. }
  345. static int stat_open(struct inode *inode, struct file *file)
  346. {
  347. return single_open(file, stat_show, inode->i_private);
  348. }
  349. static const struct file_operations stat_fops = {
  350. .owner = THIS_MODULE,
  351. .open = stat_open,
  352. .read = seq_read,
  353. .llseek = seq_lseek,
  354. .release = single_release,
  355. };
  356. int f2fs_build_stats(struct f2fs_sb_info *sbi)
  357. {
  358. struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
  359. struct f2fs_stat_info *si;
  360. si = kzalloc(sizeof(struct f2fs_stat_info), GFP_KERNEL);
  361. if (!si)
  362. return -ENOMEM;
  363. si->all_area_segs = le32_to_cpu(raw_super->segment_count);
  364. si->sit_area_segs = le32_to_cpu(raw_super->segment_count_sit);
  365. si->nat_area_segs = le32_to_cpu(raw_super->segment_count_nat);
  366. si->ssa_area_segs = le32_to_cpu(raw_super->segment_count_ssa);
  367. si->main_area_segs = le32_to_cpu(raw_super->segment_count_main);
  368. si->main_area_sections = le32_to_cpu(raw_super->section_count);
  369. si->main_area_zones = si->main_area_sections /
  370. le32_to_cpu(raw_super->secs_per_zone);
  371. si->sbi = sbi;
  372. sbi->stat_info = si;
  373. atomic64_set(&sbi->total_hit_ext, 0);
  374. atomic64_set(&sbi->read_hit_rbtree, 0);
  375. atomic64_set(&sbi->read_hit_largest, 0);
  376. atomic64_set(&sbi->read_hit_cached, 0);
  377. atomic_set(&sbi->inline_xattr, 0);
  378. atomic_set(&sbi->inline_inode, 0);
  379. atomic_set(&sbi->inline_dir, 0);
  380. atomic_set(&sbi->inplace_count, 0);
  381. atomic_set(&sbi->aw_cnt, 0);
  382. atomic_set(&sbi->max_aw_cnt, 0);
  383. mutex_lock(&f2fs_stat_mutex);
  384. list_add_tail(&si->stat_list, &f2fs_stat_list);
  385. mutex_unlock(&f2fs_stat_mutex);
  386. return 0;
  387. }
  388. void f2fs_destroy_stats(struct f2fs_sb_info *sbi)
  389. {
  390. struct f2fs_stat_info *si = F2FS_STAT(sbi);
  391. mutex_lock(&f2fs_stat_mutex);
  392. list_del(&si->stat_list);
  393. mutex_unlock(&f2fs_stat_mutex);
  394. kfree(si);
  395. }
  396. int __init f2fs_create_root_stats(void)
  397. {
  398. struct dentry *file;
  399. f2fs_debugfs_root = debugfs_create_dir("f2fs", NULL);
  400. if (!f2fs_debugfs_root)
  401. return -ENOMEM;
  402. file = debugfs_create_file("status", S_IRUGO, f2fs_debugfs_root,
  403. NULL, &stat_fops);
  404. if (!file) {
  405. debugfs_remove(f2fs_debugfs_root);
  406. f2fs_debugfs_root = NULL;
  407. return -ENOMEM;
  408. }
  409. return 0;
  410. }
  411. void f2fs_destroy_root_stats(void)
  412. {
  413. if (!f2fs_debugfs_root)
  414. return;
  415. debugfs_remove_recursive(f2fs_debugfs_root);
  416. f2fs_debugfs_root = NULL;
  417. }