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 * Portions Copyright (c) 2008-2009 Stacey Son <sson@FreeBSD.org>
22 *
23 * $FreeBSD$
24 *
25 */
26
27/*
28 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
29 * Use is subject to license terms.
30 */
31
32#include "opt_kdtrace.h"
33
34#include <sys/cdefs.h>
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/conf.h>
38#include <sys/kernel.h>
39#include <sys/limits.h>
40#include <sys/lock.h>
41#include <sys/linker.h>
42#include <sys/module.h>
43#include <sys/mutex.h>
44
45#include <sys/dtrace.h>
46#include <sys/lockstat.h>
47
48#if defined(__i386__) || defined(__amd64__)
49#define LOCKSTAT_AFRAMES 1
50#else
51#error "architecture not supported"
52#endif
53
54static d_open_t lockstat_open;
55static void     lockstat_provide(void *, dtrace_probedesc_t *);
56static void     lockstat_destroy(void *, dtrace_id_t, void *);
57static void     lockstat_enable(void *, dtrace_id_t, void *);
58static void     lockstat_disable(void *, dtrace_id_t, void *);
59static void     lockstat_load(void *);
60static int     	lockstat_unload(void);
61
62
63typedef struct lockstat_probe {
64	char		*lsp_func;
65	char		*lsp_name;
66	int		lsp_probe;
67	dtrace_id_t	lsp_id;
68#ifdef __FreeBSD__
69	int		lsp_frame;
70#endif
71} lockstat_probe_t;
72
73#ifdef __FreeBSD__
74lockstat_probe_t lockstat_probes[] =
75{
76  /* Spin Locks */
77  { LS_MTX_SPIN_LOCK,	LSS_ACQUIRE,	LS_MTX_SPIN_LOCK_ACQUIRE,
78	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
79  { LS_MTX_SPIN_LOCK, 	LSS_SPIN,	LS_MTX_SPIN_LOCK_SPIN,
80	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
81  { LS_MTX_SPIN_UNLOCK,	LSS_RELEASE,	LS_MTX_SPIN_UNLOCK_RELEASE,
82	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
83  /* Adaptive Locks */
84  { LS_MTX_LOCK,	LSA_ACQUIRE,	LS_MTX_LOCK_ACQUIRE,
85	  DTRACE_IDNONE, (LOCKSTAT_AFRAMES + 1) },
86  { LS_MTX_LOCK,	LSA_BLOCK,	LS_MTX_LOCK_BLOCK,
87	  DTRACE_IDNONE, (LOCKSTAT_AFRAMES + 1) },
88  { LS_MTX_LOCK,	LSA_SPIN,	LS_MTX_LOCK_SPIN,
89	  DTRACE_IDNONE, (LOCKSTAT_AFRAMES + 1) },
90  { LS_MTX_UNLOCK,	LSA_RELEASE,	LS_MTX_UNLOCK_RELEASE,
91	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
92  { LS_MTX_TRYLOCK,	LSA_ACQUIRE,	LS_MTX_TRYLOCK_ACQUIRE,
93	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
94  /* Reader/Writer Locks */
95  { LS_RW_RLOCK,	LSR_ACQUIRE,	LS_RW_RLOCK_ACQUIRE,
96	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
97  { LS_RW_RLOCK,	LSR_BLOCK,	LS_RW_RLOCK_BLOCK,
98	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
99  { LS_RW_RLOCK,	LSR_SPIN,	LS_RW_RLOCK_SPIN,
100	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
101  { LS_RW_RUNLOCK,	LSR_RELEASE,	LS_RW_RUNLOCK_RELEASE,
102	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
103  { LS_RW_WLOCK,	LSR_ACQUIRE,	LS_RW_WLOCK_ACQUIRE,
104	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
105  { LS_RW_WLOCK,	LSR_BLOCK,	LS_RW_WLOCK_BLOCK,
106	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
107  { LS_RW_WLOCK,	LSR_SPIN,	LS_RW_WLOCK_SPIN,
108	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
109  { LS_RW_WUNLOCK,	LSR_RELEASE,	LS_RW_WUNLOCK_RELEASE,
110	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
111  { LS_RW_TRYUPGRADE,	LSR_UPGRADE,   	LS_RW_TRYUPGRADE_UPGRADE,
112	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
113  { LS_RW_DOWNGRADE,	LSR_DOWNGRADE, 	LS_RW_DOWNGRADE_DOWNGRADE,
114	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
115  /* Shared/Exclusive Locks */
116  { LS_SX_SLOCK,	LSX_ACQUIRE,	LS_SX_SLOCK_ACQUIRE,
117	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
118  { LS_SX_SLOCK,	LSX_BLOCK,	LS_SX_SLOCK_BLOCK,
119	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
120  { LS_SX_SLOCK,	LSX_SPIN,	LS_SX_SLOCK_SPIN,
121	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
122  { LS_SX_SUNLOCK,	LSX_RELEASE,	LS_SX_SUNLOCK_RELEASE,
123	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
124  { LS_SX_XLOCK,	LSX_ACQUIRE,	LS_SX_XLOCK_ACQUIRE,
125	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
126  { LS_SX_XLOCK,	LSX_BLOCK,	LS_SX_XLOCK_BLOCK,
127	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
128  { LS_SX_XLOCK,	LSX_SPIN,	LS_SX_XLOCK_SPIN,
129	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
130  { LS_SX_XUNLOCK,	LSX_RELEASE,	LS_SX_XUNLOCK_RELEASE,
131	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
132  { LS_SX_TRYUPGRADE,	LSX_UPGRADE,	LS_SX_TRYUPGRADE_UPGRADE,
133	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
134  { LS_SX_DOWNGRADE,	LSX_DOWNGRADE,	LS_SX_DOWNGRADE_DOWNGRADE,
135	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
136  /* Thread Locks */
137  { LS_THREAD_LOCK,	LST_SPIN,	LS_THREAD_LOCK_SPIN,
138	  DTRACE_IDNONE, LOCKSTAT_AFRAMES },
139  { NULL }
140};
141#else
142#error "OS not supported"
143#endif
144
145
146static struct cdevsw lockstat_cdevsw = {
147	.d_version	= D_VERSION,
148	.d_open		= lockstat_open,
149	.d_name		= "lockstat",
150};
151
152static struct cdev		*lockstat_cdev;
153static dtrace_provider_id_t 	lockstat_id;
154
155/*ARGSUSED*/
156static void
157lockstat_enable(void *arg, dtrace_id_t id, void *parg)
158{
159	lockstat_probe_t *probe = parg;
160
161	ASSERT(!lockstat_probemap[probe->lsp_probe]);
162
163	lockstat_probemap[probe->lsp_probe] = id;
164#ifdef DOODAD
165	membar_producer();
166#endif
167
168	lockstat_probe_func = dtrace_probe;
169#ifdef DOODAD
170	membar_producer();
171
172	lockstat_hot_patch();
173	membar_producer();
174#endif
175}
176
177/*ARGSUSED*/
178static void
179lockstat_disable(void *arg, dtrace_id_t id, void *parg)
180{
181	lockstat_probe_t *probe = parg;
182	int i;
183
184	ASSERT(lockstat_probemap[probe->lsp_probe]);
185
186	lockstat_probemap[probe->lsp_probe] = 0;
187#ifdef DOODAD
188	lockstat_hot_patch();
189	membar_producer();
190#endif
191
192	/*
193	 * See if we have any probes left enabled.
194	 */
195	for (i = 0; i < LS_NPROBES; i++) {
196		if (lockstat_probemap[i]) {
197			/*
198			 * This probe is still enabled.  We don't need to deal
199			 * with waiting for all threads to be out of the
200			 * lockstat critical sections; just return.
201			 */
202			return;
203		}
204	}
205
206}
207
208/*ARGSUSED*/
209static int
210lockstat_open(struct cdev *dev __unused, int oflags __unused,
211	      int devtype __unused, struct thread *td __unused)
212{
213	return (0);
214}
215
216/*ARGSUSED*/
217static void
218lockstat_provide(void *arg, dtrace_probedesc_t *desc)
219{
220	int i = 0;
221
222	for (i = 0; lockstat_probes[i].lsp_func != NULL; i++) {
223		lockstat_probe_t *probe = &lockstat_probes[i];
224
225		if (dtrace_probe_lookup(lockstat_id, "kernel",
226		    probe->lsp_func, probe->lsp_name) != 0)
227			continue;
228
229		ASSERT(!probe->lsp_id);
230#ifdef __FreeBSD__
231		probe->lsp_id = dtrace_probe_create(lockstat_id,
232		    "kernel", probe->lsp_func, probe->lsp_name,
233		    probe->lsp_frame, probe);
234#else
235		probe->lsp_id = dtrace_probe_create(lockstat_id,
236		    "kernel", probe->lsp_func, probe->lsp_name,
237		    LOCKSTAT_AFRAMES, probe);
238#endif
239	}
240}
241
242/*ARGSUSED*/
243static void
244lockstat_destroy(void *arg, dtrace_id_t id, void *parg)
245{
246	lockstat_probe_t *probe = parg;
247
248	ASSERT(!lockstat_probemap[probe->lsp_probe]);
249	probe->lsp_id = 0;
250}
251
252static dtrace_pattr_t lockstat_attr = {
253{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
254{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
255{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
256{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
257{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON },
258};
259
260static dtrace_pops_t lockstat_pops = {
261	lockstat_provide,
262	NULL,
263	lockstat_enable,
264	lockstat_disable,
265	NULL,
266	NULL,
267	NULL,
268	NULL,
269	NULL,
270	lockstat_destroy
271};
272
273static void
274lockstat_load(void *dummy)
275{
276	/* Create the /dev/dtrace/lockstat entry. */
277	lockstat_cdev = make_dev(&lockstat_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600,
278	    "dtrace/lockstat");
279
280	if (dtrace_register("lockstat", &lockstat_attr, DTRACE_PRIV_USER,
281	    NULL, &lockstat_pops, NULL, &lockstat_id) != 0)
282	        return;
283}
284
285static int
286lockstat_unload()
287{
288	int error = 0;
289
290	if ((error = dtrace_unregister(lockstat_id)) != 0)
291	    return (error);
292
293	destroy_dev(lockstat_cdev);
294
295	return (error);
296}
297
298/* ARGSUSED */
299static int
300lockstat_modevent(module_t mod __unused, int type, void *data __unused)
301{
302	int error = 0;
303
304	switch (type) {
305	case MOD_LOAD:
306		break;
307
308	case MOD_UNLOAD:
309		break;
310
311	case MOD_SHUTDOWN:
312		break;
313
314	default:
315		error = EOPNOTSUPP;
316		break;
317	}
318	return (error);
319}
320
321SYSINIT(lockstat_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, lockstat_load, NULL);
322SYSUNINIT(lockstat_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, lockstat_unload, NULL);
323
324DEV_MODULE(lockstat, lockstat_modevent, NULL);
325MODULE_VERSION(lockstat, 1);
326MODULE_DEPEND(lockstat, dtrace, 1, 1, 1);
327MODULE_DEPEND(lockstat, opensolaris, 1, 1, 1);
328