xref: /freebsd/sys/dev/hwpmc/hwpmc_arm64_md.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
1 /*-
2  * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
3  * All rights reserved.
4  *
5  * This software was developed by the University of Cambridge Computer
6  * Laboratory with support from ARM Ltd.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/pmc.h>
34 
35 #include <vm/vm.h>
36 #include <vm/pmap.h>
37 
38 #include <machine/cpu.h>
39 #include <machine/md_var.h>
40 #include <machine/pmc_mdep.h>
41 #include <machine/stack.h>
42 #include <machine/vmparam.h>
43 
44 struct pmc_mdep *
45 pmc_md_initialize(void)
46 {
47 
48 	return (pmc_arm64_initialize());
49 }
50 
51 void
52 pmc_md_finalize(struct pmc_mdep *md)
53 {
54 
55 	pmc_arm64_finalize(md);
56 }
57 
58 int
59 pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples, struct trapframe *tf)
60 {
61 	struct unwind_state frame;
62 	int count;
63 
64 	KASSERT(TRAPF_USERMODE(tf) == 0,("[arm64,%d] not a kernel backtrace",
65 	    __LINE__));
66 
67 	frame.pc = PMC_TRAPFRAME_TO_PC(tf);
68 	*cc++ = frame.pc;
69 
70 	if (maxsamples <= 1)
71 		return (1);
72 
73 	frame.fp = PMC_TRAPFRAME_TO_FP(tf);
74 	if (!PMC_IN_KERNEL(frame.pc) || !PMC_IN_KERNEL_STACK(frame.fp))
75 		return (1);
76 
77 	for (count = 1; count < maxsamples; count++) {
78 		if (!unwind_frame(curthread, &frame))
79 			break;
80 		if (!PMC_IN_KERNEL(frame.pc))
81 			break;
82 		*cc++ = frame.pc;
83 	}
84 
85 	return (count);
86 }
87 
88 int
89 pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
90     struct trapframe *tf)
91 {
92 	uintptr_t pc, r, oldfp, fp;
93 	int count;
94 
95 	KASSERT(TRAPF_USERMODE(tf), ("[arm64,%d] Not a user trap frame tf=%p",
96 	    __LINE__, (void *) tf));
97 
98 	pc = PMC_TRAPFRAME_TO_PC(tf);
99 	*cc++ = pc;
100 
101 	if (maxsamples <= 1)
102 		return (1);
103 
104 	oldfp = fp = PMC_TRAPFRAME_TO_FP(tf);
105 
106 	if (!PMC_IN_USERSPACE(pc) ||
107 	    !PMC_IN_USERSPACE(fp))
108 		return (1);
109 
110 	for (count = 1; count < maxsamples; count++) {
111 		/* Use saved lr as pc. */
112 		r = fp + sizeof(uintptr_t);
113 		if (copyin((void *)r, &pc, sizeof(pc)) != 0)
114 			break;
115 		if (!PMC_IN_USERSPACE(pc))
116 			break;
117 
118 		*cc++ = pc;
119 
120 		/* Switch to next frame up */
121 		oldfp = fp;
122 		r = fp;
123 		if (copyin((void *)r, &fp, sizeof(fp)) != 0)
124 			break;
125 		if (fp < oldfp || !PMC_IN_USERSPACE(fp))
126 			break;
127 	}
128 
129 	return (count);
130 }
131