xref: /freebsd/sys/contrib/openzfs/module/zfs/dbuf_stats.c (revision 9e5787d2284e187abb5b654d924394a65772e004)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 #include <sys/zfs_context.h>
23 #include <sys/dbuf.h>
24 #include <sys/dmu_objset.h>
25 
26 /*
27  * Calculate the index of the arc header for the state, disabled by default.
28  */
29 int zfs_dbuf_state_index = 0;
30 
31 /*
32  * ==========================================================================
33  * Dbuf Hash Read Routines
34  * ==========================================================================
35  */
36 typedef struct dbuf_stats_t {
37 	kmutex_t		lock;
38 	kstat_t			*kstat;
39 	dbuf_hash_table_t	*hash;
40 	int			idx;
41 } dbuf_stats_t;
42 
43 static dbuf_stats_t dbuf_stats_hash_table;
44 
45 static int
46 dbuf_stats_hash_table_headers(char *buf, size_t size)
47 {
48 	(void) snprintf(buf, size,
49 	    "%-96s | %-119s | %s\n"
50 	    "%-16s %-8s %-8s %-8s %-8s %-10s %-8s %-5s %-5s %-7s %3s | "
51 	    "%-5s %-5s %-9s %-6s %-8s %-12s "
52 	    "%-6s %-6s %-6s %-6s %-6s %-8s %-8s %-8s %-6s | "
53 	    "%-6s %-6s %-8s %-8s %-6s %-6s %-6s %-8s %-8s\n",
54 	    "dbuf", "arcbuf", "dnode", "pool", "objset", "object", "level",
55 	    "blkid", "offset", "dbsize", "meta", "state", "dbholds", "dbc",
56 	    "list", "atype", "flags", "count", "asize", "access",
57 	    "mru", "gmru", "mfu", "gmfu", "l2", "l2_dattr", "l2_asize",
58 	    "l2_comp", "aholds", "dtype", "btype", "data_bs", "meta_bs",
59 	    "bsize", "lvls", "dholds", "blocks", "dsize");
60 
61 	return (0);
62 }
63 
64 static int
65 __dbuf_stats_hash_table_data(char *buf, size_t size, dmu_buf_impl_t *db)
66 {
67 	arc_buf_info_t abi = { 0 };
68 	dmu_object_info_t doi = { 0 };
69 	dnode_t *dn = DB_DNODE(db);
70 	size_t nwritten;
71 
72 	if (db->db_buf)
73 		arc_buf_info(db->db_buf, &abi, zfs_dbuf_state_index);
74 
75 	__dmu_object_info_from_dnode(dn, &doi);
76 
77 	nwritten = snprintf(buf, size,
78 	    "%-16s %-8llu %-8lld %-8lld %-8lld %-10llu %-8llu %-5d %-5d "
79 	    "%-7lu %-3d | %-5d %-5d 0x%-7x %-6lu %-8llu %-12llu "
80 	    "%-6lu %-6lu %-6lu %-6lu %-6lu %-8llu %-8llu %-8d %-6lu | "
81 	    "%-6d %-6d %-8lu %-8lu %-6llu %-6lu %-6lu %-8llu %-8llu\n",
82 	    /* dmu_buf_impl_t */
83 	    spa_name(dn->dn_objset->os_spa),
84 	    (u_longlong_t)dmu_objset_id(db->db_objset),
85 	    (longlong_t)db->db.db_object,
86 	    (longlong_t)db->db_level,
87 	    (longlong_t)db->db_blkid,
88 	    (u_longlong_t)db->db.db_offset,
89 	    (u_longlong_t)db->db.db_size,
90 	    !!dbuf_is_metadata(db),
91 	    db->db_state,
92 	    (ulong_t)zfs_refcount_count(&db->db_holds),
93 	    multilist_link_active(&db->db_cache_link),
94 	    /* arc_buf_info_t */
95 	    abi.abi_state_type,
96 	    abi.abi_state_contents,
97 	    abi.abi_flags,
98 	    (ulong_t)abi.abi_bufcnt,
99 	    (u_longlong_t)abi.abi_size,
100 	    (u_longlong_t)abi.abi_access,
101 	    (ulong_t)abi.abi_mru_hits,
102 	    (ulong_t)abi.abi_mru_ghost_hits,
103 	    (ulong_t)abi.abi_mfu_hits,
104 	    (ulong_t)abi.abi_mfu_ghost_hits,
105 	    (ulong_t)abi.abi_l2arc_hits,
106 	    (u_longlong_t)abi.abi_l2arc_dattr,
107 	    (u_longlong_t)abi.abi_l2arc_asize,
108 	    abi.abi_l2arc_compress,
109 	    (ulong_t)abi.abi_holds,
110 	    /* dmu_object_info_t */
111 	    doi.doi_type,
112 	    doi.doi_bonus_type,
113 	    (ulong_t)doi.doi_data_block_size,
114 	    (ulong_t)doi.doi_metadata_block_size,
115 	    (u_longlong_t)doi.doi_bonus_size,
116 	    (ulong_t)doi.doi_indirection,
117 	    (ulong_t)zfs_refcount_count(&dn->dn_holds),
118 	    (u_longlong_t)doi.doi_fill_count,
119 	    (u_longlong_t)doi.doi_max_offset);
120 
121 	if (nwritten >= size)
122 		return (size);
123 
124 	return (nwritten + 1);
125 }
126 
127 static int
128 dbuf_stats_hash_table_data(char *buf, size_t size, void *data)
129 {
130 	dbuf_stats_t *dsh = (dbuf_stats_t *)data;
131 	dbuf_hash_table_t *h = dsh->hash;
132 	dmu_buf_impl_t *db;
133 	int length, error = 0;
134 
135 	ASSERT3S(dsh->idx, >=, 0);
136 	ASSERT3S(dsh->idx, <=, h->hash_table_mask);
137 	memset(buf, 0, size);
138 
139 	mutex_enter(DBUF_HASH_MUTEX(h, dsh->idx));
140 	for (db = h->hash_table[dsh->idx]; db != NULL; db = db->db_hash_next) {
141 		/*
142 		 * Returning ENOMEM will cause the data and header functions
143 		 * to be called with a larger scratch buffers.
144 		 */
145 		if (size < 512) {
146 			error = SET_ERROR(ENOMEM);
147 			break;
148 		}
149 
150 		mutex_enter(&db->db_mtx);
151 
152 		if (db->db_state != DB_EVICTING) {
153 			length = __dbuf_stats_hash_table_data(buf, size, db);
154 			buf += length;
155 			size -= length;
156 		}
157 
158 		mutex_exit(&db->db_mtx);
159 	}
160 	mutex_exit(DBUF_HASH_MUTEX(h, dsh->idx));
161 
162 	return (error);
163 }
164 
165 static void *
166 dbuf_stats_hash_table_addr(kstat_t *ksp, loff_t n)
167 {
168 	dbuf_stats_t *dsh = ksp->ks_private;
169 
170 	ASSERT(MUTEX_HELD(&dsh->lock));
171 
172 	if (n <= dsh->hash->hash_table_mask) {
173 		dsh->idx = n;
174 		return (dsh);
175 	}
176 
177 	return (NULL);
178 }
179 
180 static void
181 dbuf_stats_hash_table_init(dbuf_hash_table_t *hash)
182 {
183 	dbuf_stats_t *dsh = &dbuf_stats_hash_table;
184 	kstat_t *ksp;
185 
186 	mutex_init(&dsh->lock, NULL, MUTEX_DEFAULT, NULL);
187 	dsh->hash = hash;
188 
189 	ksp = kstat_create("zfs", 0, "dbufs", "misc",
190 	    KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL);
191 	dsh->kstat = ksp;
192 
193 	if (ksp) {
194 		ksp->ks_lock = &dsh->lock;
195 		ksp->ks_ndata = UINT32_MAX;
196 		ksp->ks_private = dsh;
197 		kstat_set_raw_ops(ksp, dbuf_stats_hash_table_headers,
198 		    dbuf_stats_hash_table_data, dbuf_stats_hash_table_addr);
199 		kstat_install(ksp);
200 	}
201 }
202 
203 static void
204 dbuf_stats_hash_table_destroy(void)
205 {
206 	dbuf_stats_t *dsh = &dbuf_stats_hash_table;
207 	kstat_t *ksp;
208 
209 	ksp = dsh->kstat;
210 	if (ksp)
211 		kstat_delete(ksp);
212 
213 	mutex_destroy(&dsh->lock);
214 }
215 
216 void
217 dbuf_stats_init(dbuf_hash_table_t *hash)
218 {
219 	dbuf_stats_hash_table_init(hash);
220 }
221 
222 void
223 dbuf_stats_destroy(void)
224 {
225 	dbuf_stats_hash_table_destroy();
226 }
227 
228 /* BEGIN CSTYLED */
229 ZFS_MODULE_PARAM(zfs, zfs_, dbuf_state_index, INT, ZMOD_RW,
230 	"Calculate arc header index");
231 /* END CSTYLED */
232