xref: /freebsd/sys/cddl/dev/dtrace/arm/dtrace_subr.c (revision 01b792f1f535c12a1a14000cf3360ef6c36cee2d)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  *
22  * $FreeBSD$
23  *
24  */
25 /*
26  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/types.h>
36 #include <sys/kernel.h>
37 #include <sys/malloc.h>
38 #include <sys/kmem.h>
39 #include <sys/smp.h>
40 #include <sys/dtrace_impl.h>
41 #include <sys/dtrace_bsd.h>
42 #include <machine/armreg.h>
43 #include <machine/clock.h>
44 #include <machine/frame.h>
45 #include <machine/trap.h>
46 #include <vm/pmap.h>
47 
48 #define	DELAYBRANCH(x)	((int)(x) < 0)
49 
50 extern uintptr_t 	dtrace_in_probe_addr;
51 extern int		dtrace_in_probe;
52 extern dtrace_id_t	dtrace_probeid_error;
53 extern int (*dtrace_invop_jump_addr)(struct trapframe *);
54 
55 int dtrace_invop(uintptr_t, uintptr_t *, uintptr_t);
56 void dtrace_invop_init(void);
57 void dtrace_invop_uninit(void);
58 
59 typedef struct dtrace_invop_hdlr {
60 	int (*dtih_func)(uintptr_t, uintptr_t *, uintptr_t);
61 	struct dtrace_invop_hdlr *dtih_next;
62 } dtrace_invop_hdlr_t;
63 
64 dtrace_invop_hdlr_t *dtrace_invop_hdlr;
65 
66 int
67 dtrace_invop(uintptr_t addr, uintptr_t *stack, uintptr_t eax)
68 {
69 	dtrace_invop_hdlr_t *hdlr;
70 	int rval;
71 
72 	for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next)
73 		if ((rval = hdlr->dtih_func(addr, stack, eax)) != 0)
74 			return (rval);
75 
76 	return (0);
77 }
78 
79 
80 void
81 dtrace_invop_add(int (*func)(uintptr_t, uintptr_t *, uintptr_t))
82 {
83 	dtrace_invop_hdlr_t *hdlr;
84 
85 	hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP);
86 	hdlr->dtih_func = func;
87 	hdlr->dtih_next = dtrace_invop_hdlr;
88 	dtrace_invop_hdlr = hdlr;
89 }
90 
91 void
92 dtrace_invop_remove(int (*func)(uintptr_t, uintptr_t *, uintptr_t))
93 {
94 	dtrace_invop_hdlr_t *hdlr = dtrace_invop_hdlr, *prev = NULL;
95 
96 	for (;;) {
97 		if (hdlr == NULL)
98 			panic("attempt to remove non-existent invop handler");
99 
100 		if (hdlr->dtih_func == func)
101 			break;
102 
103 		prev = hdlr;
104 		hdlr = hdlr->dtih_next;
105 	}
106 
107 	if (prev == NULL) {
108 		ASSERT(dtrace_invop_hdlr == hdlr);
109 		dtrace_invop_hdlr = hdlr->dtih_next;
110 	} else {
111 		ASSERT(dtrace_invop_hdlr != hdlr);
112 		prev->dtih_next = hdlr->dtih_next;
113 	}
114 
115 	kmem_free(hdlr, 0);
116 }
117 
118 
119 /*ARGSUSED*/
120 void
121 dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit))
122 {
123 	printf("IMPLEMENT ME: dtrace_toxic_ranges\n");
124 }
125 
126 void
127 dtrace_xcall(processorid_t cpu, dtrace_xcall_t func, void *arg)
128 {
129 	cpuset_t cpus;
130 
131 	if (cpu == DTRACE_CPUALL)
132 		cpus = all_cpus;
133 	else
134 		CPU_SETOF(cpu, &cpus);
135 
136 	smp_rendezvous_cpus(cpus, smp_no_rendevous_barrier, func,
137 	    smp_no_rendevous_barrier, arg);
138 }
139 
140 static void
141 dtrace_sync_func(void)
142 {
143 }
144 
145 void
146 dtrace_sync(void)
147 {
148 	dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_sync_func, NULL);
149 }
150 
151 /*
152  * DTrace needs a high resolution time function which can
153  * be called from a probe context and guaranteed not to have
154  * instrumented with probes itself.
155  *
156  * Returns nanoseconds since boot.
157  */
158 uint64_t
159 dtrace_gethrtime()
160 {
161 	struct	timespec curtime;
162 
163 	nanouptime(&curtime);
164 
165 	return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec);
166 
167 }
168 
169 uint64_t
170 dtrace_gethrestime(void)
171 {
172 	struct	timespec curtime;
173 
174 	getnanotime(&curtime);
175 
176 	return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec);
177 }
178 
179 /* Function to handle DTrace traps during probes. See amd64/amd64/trap.c */
180 int
181 dtrace_trap(struct trapframe *frame, u_int type)
182 {
183 	/*
184 	 * A trap can occur while DTrace executes a probe. Before
185 	 * executing the probe, DTrace blocks re-scheduling and sets
186 	 * a flag in it's per-cpu flags to indicate that it doesn't
187 	 * want to fault. On returning from the probe, the no-fault
188 	 * flag is cleared and finally re-scheduling is enabled.
189 	 *
190 	 * Check if DTrace has enabled 'no-fault' mode:
191 	 *
192 	 */
193 	if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) {
194 		/*
195 		 * There are only a couple of trap types that are expected.
196 		 * All the rest will be handled in the usual way.
197 		 */
198 		switch (type) {
199 		/* Page fault. */
200 		case FAULT_ALIGN:
201 			/* Flag a bad address. */
202 			cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR;
203 			cpu_core[curcpu].cpuc_dtrace_illval = 0;
204 
205 			/*
206 			 * Offset the instruction pointer to the instruction
207 			 * following the one causing the fault.
208 			 */
209 			frame->tf_pc += sizeof(int);
210 			return (1);
211 		default:
212 			/* Handle all other traps in the usual way. */
213 			break;
214 		}
215 	}
216 
217 	/* Handle the trap in the usual way. */
218 	return (0);
219 }
220 
221 void
222 dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which,
223     int fault, int fltoffs, uintptr_t illval)
224 {
225 
226 	dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state,
227 	    (uintptr_t)epid,
228 	    (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs);
229 }
230 
231 static int
232 dtrace_invop_start(struct trapframe *frame)
233 {
234 	printf("IMPLEMENT ME: %s\n", __func__);
235 	switch (dtrace_invop(frame->tf_pc, (uintptr_t *)frame, frame->tf_pc)) {
236 	case DTRACE_INVOP_PUSHM:
237 		// TODO:
238 		break;
239 	case DTRACE_INVOP_POPM:
240 		// TODO:
241 		break;
242 	case DTRACE_INVOP_B:
243 		// TODO
244 		break;
245 	default:
246 		return (-1);
247 		break;
248 	}
249 
250 	return (0);
251 }
252 
253 void dtrace_invop_init(void)
254 {
255 	dtrace_invop_jump_addr = dtrace_invop_start;
256 }
257 
258 void dtrace_invop_uninit(void)
259 {
260 	dtrace_invop_jump_addr = 0;
261 }
262