xref: /xnu-11215/bsd/dev/dtrace/lockstat.c (revision 5c2921b0)
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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/param.h>
27 #include <sys/systm.h>
28 #include <sys/errno.h>
29 #include <sys/stat.h>
30 #include <sys/ioctl.h>
31 #include <sys/conf.h>
32 #include <sys/fcntl.h>
33 #include <miscfs/devfs/devfs.h>
34 
35 #include <sys/dtrace.h>
36 #include <sys/dtrace_impl.h>
37 
38 #include <sys/dtrace_glue.h>
39 
40 #include <sys/lockstat.h>
41 
42 #include <kern/lock_stat.h>
43 
44 #define PROBE_ARGS0(a, b, c, d, e) "\000"
45 #define PROBE_ARGS1(a, b, c, d, e) a "\000"
46 #define PROBE_ARGS2(a, b, c, d, e) a "\000" b "\000"
47 #define PROBE_ARGS3(a, b, c, d, e) a "\000" b "\000" c "\000"
48 #define PROBE_ARGS4(a, b, c, d, e) a "\000" b "\000" c "\000" d "\000"
49 #define PROBE_ARGS5(a, b, c, d, e) a "\000" b "\000" c "\000" d "\000" e "\000"
50 #define PROBE_ARGS_(a, b, c, d, e, n, ...) PROBE_ARGS##n(a, b, c, d, e)
51 #define PROBE_ARGS(...) PROBE_ARGS_(__VA_ARGS__, 5, 4, 3, 2, 1, 0)
52 
53 #define LOCKSTAT_PROBE(func, name, probe, ...) \
54 	{func, name, probe, DTRACE_IDNONE, PROBE_ARGS(__VA_ARGS__)}
55 
56 #if defined(__x86_64__)
57 #define LOCKSTAT_AFRAMES 1
58 #elif   defined(__arm64__)
59 #define LOCKSTAT_AFRAMES 2
60 #else
61 #error "architecture not supported"
62 #endif
63 
64 typedef struct lockstat_probe {
65 	const char      *lsp_func;
66 	const char      *lsp_name;
67 	int             lsp_probe;
68 	dtrace_id_t     lsp_id;
69 	const char      *lsp_args;
70 } lockstat_probe_t;
71 
72 lockstat_probe_t lockstat_probes[] =
73 {
74 	// Mutex probes
75 	// .. acquire/release
76 	LOCKSTAT_PROBE(LS_LCK_MTX_LOCK, LSA_ACQUIRE, LS_LCK_MTX_LOCK_ACQUIRE, "lck_mtx_t", "lck_grp_t"),
77 	LOCKSTAT_PROBE(LS_LCK_MTX_LOCK_SPIN, LSA_ACQUIRE, LS_LCK_MTX_LOCK_SPIN_ACQUIRE, "lck_mtx_t", "lck_grp_t"),
78 	LOCKSTAT_PROBE(LS_LCK_MTX_TRY_LOCK, LSA_ACQUIRE, LS_LCK_MTX_TRY_LOCK_ACQUIRE, "lck_mtx_t", "lck_grp_t"),
79 	LOCKSTAT_PROBE(LS_LCK_MTX_TRY_LOCK_SPIN, LSA_ACQUIRE, LS_LCK_MTX_TRY_LOCK_SPIN_ACQUIRE, "lck_mtx_t", "lck_grp_t"),
80 	LOCKSTAT_PROBE(LS_LCK_MTX_UNLOCK, LSA_RELEASE, LS_LCK_MTX_UNLOCK_RELEASE, "lck_mtx_t", "lck_grp_t"),
81 
82 	// .. blocking and spinning
83 	LOCKSTAT_PROBE(LS_LCK_MTX_LOCK, LSA_BLOCK, LS_LCK_MTX_LOCK_BLOCK, "lck_mtx_t", "uint64_t", "lck_grp_t"),
84 	LOCKSTAT_PROBE(LS_LCK_MTX_LOCK, LSA_SPIN, LS_LCK_MTX_LOCK_ADAPTIVE_SPIN, "lck_mtx_t", "uint64_t", "lck_grp_t"),
85 	LOCKSTAT_PROBE(LS_LCK_MTX_LOCK_SPIN, LSA_SPIN, LS_LCK_MTX_LOCK_SPIN_SPIN, "lck_mtx_t", "uint64_t", "lck_grp_t"),
86 
87 	// RW lock probes
88 	// TODO: This should not be a uint64_t !
89 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_SHARED, LSR_ACQUIRE, LS_LCK_RW_LOCK_SHARED_ACQUIRE, "lck_rw_t", "uint64_t"),
90 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_SHARED, LSR_BLOCK, LS_LCK_RW_LOCK_SHARED_BLOCK, "lck_rw_t", "uint64_t", "_Bool", "_Bool", "int"),
91 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_SHARED, LSR_SPIN, LS_LCK_RW_LOCK_SHARED_SPIN, "lck_rw_t", "uint64_t", "_Bool", "_Bool", "int"),
92 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_EXCL, LSR_ACQUIRE, LS_LCK_RW_LOCK_EXCL_ACQUIRE, "lck_rw_t", "uint64_t"),
93 	// TODO: This should NOT be a uint64_t
94 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_EXCL, LSR_BLOCK, LS_LCK_RW_LOCK_EXCL_BLOCK, "lck_rw_t", "uint64_t", "_Bool", "_Bool", "int"),
95 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_EXCL, LSR_SPIN, LS_LCK_RW_LOCK_EXCL_SPIN, "lck_rw_t", "uint64_t", "int"),
96 	LOCKSTAT_PROBE(LS_LCK_RW_DONE, LSR_RELEASE, LS_LCK_RW_DONE_RELEASE, "lck_rw_t", "_Bool"),
97 	// TODO : This should NOT be a uint64_t
98 	LOCKSTAT_PROBE(LS_LCK_RW_TRY_LOCK_SHARED, LSR_ACQUIRE, LS_LCK_RW_TRY_LOCK_SHARED_ACQUIRE, "lck_rw_t", "uint64_t"),
99 	LOCKSTAT_PROBE(LS_LCK_RW_TRY_LOCK_EXCL, LSR_ACQUIRE, LS_LCK_RW_TRY_LOCK_EXCL_ACQUIRE, "lck_rw_t", "uint64_t"),
100 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_UPGRADE, LS_LCK_RW_LOCK_SHARED_TO_EXCL_UPGRADE, "lck_rw_t", "_Bool"),
101 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_SPIN, LS_LCK_RW_LOCK_SHARED_TO_EXCL_SPIN, "lck_rw_t", "uint64_t"),
102 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_SHARED_TO_EXCL, LSR_BLOCK, LS_LCK_RW_LOCK_SHARED_TO_EXCL_BLOCK, "lck_rw_t", "uint64_t", "_Bool", "_Bool", "int"),
103 
104 	// Spin lock probes
105 	//TODO : Separate the probes for the hw_bit from the probe for the normal hw locks
106 	LOCKSTAT_PROBE(LS_LCK_SPIN_LOCK, LSS_ACQUIRE, LS_LCK_SPIN_LOCK_ACQUIRE, "hw_lock_t"),
107 	LOCKSTAT_PROBE(LS_LCK_SPIN_LOCK, LSS_SPIN, LS_LCK_SPIN_LOCK_SPIN, "hw_lock_t", "uint64_t", "uint64_t"),
108 	LOCKSTAT_PROBE(LS_LCK_SPIN_UNLOCK, LSS_RELEASE, LS_LCK_SPIN_UNLOCK_RELEASE, "hw_lock_t"),
109 	LOCKSTAT_PROBE(LS_LCK_RW_LOCK_EXCL_TO_SHARED, LSR_DOWNGRADE, LS_LCK_RW_LOCK_EXCL_TO_SHARED_DOWNGRADE, "lck_rw_t"),
110 	// Ticket lock probes
111 	LOCKSTAT_PROBE(LS_LCK_TICKET_LOCK, LST_ACQUIRE, LS_LCK_TICKET_LOCK_ACQUIRE, "lck_ticket_t"),
112 	LOCKSTAT_PROBE(LS_LCK_TICKET_LOCK, LST_RELEASE, LS_LCK_TICKET_LOCK_RELEASE, "lck_ticket_t"),
113 	LOCKSTAT_PROBE(LS_LCK_TICKET_LOCK, LST_SPIN, LS_LCK_TICKET_LOCK_SPIN, "lck_ticket_t"),
114 	{
115 		NULL, NULL, 0, 0, NULL
116 	}
117 };
118 
119 dtrace_id_t lockstat_probemap[LS_NPROBES];
120 
121 static dtrace_provider_id_t lockstat_id;
122 
123 /*ARGSUSED*/
124 static int
lockstat_enable(void * arg,dtrace_id_t id,void * parg)125 lockstat_enable(void *arg, dtrace_id_t id, void *parg)
126 {
127 #pragma unused(arg) /* __APPLE__ */
128 
129 	lockstat_probe_t *probe = parg;
130 
131 	ASSERT(!lockstat_probemap[probe->lsp_probe]);
132 
133 	lockstat_probemap[probe->lsp_probe] = id;
134 	lck_grp_enable_feature(LCK_DEBUG_LOCKSTAT);
135 
136 	return 0;
137 }
138 
139 /*ARGSUSED*/
140 static void
lockstat_disable(void * arg,dtrace_id_t id,void * parg)141 lockstat_disable(void *arg, dtrace_id_t id, void *parg)
142 {
143 #pragma unused(arg, id) /* __APPLE__ */
144 
145 	lockstat_probe_t *probe = parg;
146 
147 	ASSERT(lockstat_probemap[probe->lsp_probe]);
148 
149 	lockstat_probemap[probe->lsp_probe] = 0;
150 	lck_grp_disable_feature(LCK_DEBUG_LOCKSTAT);
151 }
152 
153 /*ARGSUSED*/
154 static void
lockstat_provide(void * arg,const dtrace_probedesc_t * desc)155 lockstat_provide(void *arg, const dtrace_probedesc_t *desc)
156 {
157 #pragma unused(arg, desc) /* __APPLE__ */
158 
159 	int i = 0;
160 
161 	for (i = 0; lockstat_probes[i].lsp_func != NULL; i++) {
162 		lockstat_probe_t *probe = &lockstat_probes[i];
163 
164 		if (dtrace_probe_lookup(lockstat_id, "mach_kernel",
165 		    probe->lsp_func, probe->lsp_name) != 0) {
166 			continue;
167 		}
168 
169 		ASSERT(!probe->lsp_id);
170 		probe->lsp_id = dtrace_probe_create(lockstat_id,
171 		    "mach_kernel", probe->lsp_func, probe->lsp_name,
172 		    LOCKSTAT_AFRAMES, probe);
173 	}
174 }
175 
176 
177 /*ARGSUSED*/
178 static void
lockstat_destroy(void * arg,dtrace_id_t id,void * parg)179 lockstat_destroy(void *arg, dtrace_id_t id, void *parg)
180 {
181 #pragma unused(arg, id)
182 
183 	lockstat_probe_t *probe = parg;
184 
185 	ASSERT(!lockstat_probemap[probe->lsp_probe]);
186 	probe->lsp_id = 0;
187 }
188 
189 static void
lockstat_getargdesc(void * arg,dtrace_id_t id,void * parg,dtrace_argdesc_t * desc)190 lockstat_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc)
191 {
192 #pragma unused(arg, id)
193 	lockstat_probe_t *probe = parg;
194 	const char* argdesc = probe->lsp_args;
195 	int narg = 0;
196 
197 	desc->dtargd_native[0] = '\0';
198 	desc->dtargd_xlate[0] = '\0';
199 
200 	while (argdesc[0] != '\0') {
201 		if (narg == desc->dtargd_ndx) {
202 			strlcpy(desc->dtargd_native, argdesc, DTRACE_ARGTYPELEN);
203 			return;
204 		}
205 		argdesc += strlen(argdesc) + 1;
206 		narg++;
207 	}
208 
209 	desc->dtargd_ndx = DTRACE_ARGNONE;
210 }
211 
212 static dtrace_pattr_t lockstat_attr = {
213 	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
214 	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
215 	{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
216 	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
217 	{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
218 };
219 
220 static dtrace_pops_t lockstat_pops = {
221 	.dtps_provide =         lockstat_provide,
222 	.dtps_provide_module =  NULL,
223 	.dtps_enable =          lockstat_enable,
224 	.dtps_disable =         lockstat_disable,
225 	.dtps_suspend =         NULL,
226 	.dtps_resume =          NULL,
227 	.dtps_getargdesc =      lockstat_getargdesc,
228 	.dtps_getargval =       NULL,
229 	.dtps_usermode =        NULL,
230 	.dtps_destroy =         lockstat_destroy
231 };
232 
233 static int
lockstat_attach(dev_info_t * devi)234 lockstat_attach(dev_info_t *devi)
235 {
236 	if (ddi_create_minor_node(devi, "lockstat", S_IFCHR, 0,
237 	    DDI_PSEUDO, 0) == DDI_FAILURE ||
238 	    dtrace_register("lockstat", &lockstat_attr, DTRACE_PRIV_KERNEL,
239 	    NULL, &lockstat_pops, NULL, &lockstat_id) != 0) {
240 		ddi_remove_minor_node(devi, NULL);
241 		return DDI_FAILURE;
242 	}
243 
244 	return DDI_SUCCESS;
245 }
246 
247 static int
_lockstat_open(dev_t dev,int flags,int devtype,struct proc * p)248 _lockstat_open(dev_t dev, int flags, int devtype, struct proc *p)
249 {
250 #pragma unused(dev,flags,devtype,p)
251 	return 0;
252 }
253 
254 
255 static const struct cdevsw lockstat_cdevsw =
256 {
257 	.d_open = _lockstat_open,
258 	.d_close = eno_opcl,
259 	.d_read = eno_rdwrt,
260 	.d_write = eno_rdwrt,
261 	.d_ioctl = eno_ioctl,
262 	.d_stop = eno_stop,
263 	.d_reset = eno_reset,
264 	.d_select = eno_select,
265 	.d_mmap = eno_mmap,
266 	.d_strategy = eno_strat,
267 	.d_reserved_1 = eno_getc,
268 	.d_reserved_2 = eno_putc,
269 };
270 
271 void lockstat_init( void );
272 
273 void
lockstat_init(void)274 lockstat_init( void )
275 {
276 	int majdevno = cdevsw_add(-1, &lockstat_cdevsw);
277 
278 	if (majdevno < 0) {
279 		printf("lockstat_init: failed to allocate a major number!\n");
280 		return;
281 	}
282 
283 	lockstat_attach((dev_info_t*)(uintptr_t)majdevno);
284 }
285