aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/tools/testing/selftests/rseq/rseq-mips.h
blob: 42ef8e946693f139ba9c8f8a7f86eb30412759f6 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
/*
 * Author: Paul Burton <paul.burton@mips.com>
 * (C) Copyright 2018 MIPS Tech LLC
 * (C) Copyright 2016-2022 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

/*
 * RSEQ_SIG uses the break instruction. The instruction pattern is:
 *
 * On MIPS:
 *	0350000d        break     0x350
 *
 * On nanoMIPS:
 *      00100350        break     0x350
 *
 * On microMIPS:
 *      0000d407        break     0x350
 *
 * For nanoMIPS32 and microMIPS, the instruction stream is encoded as 16-bit
 * halfwords, so the signature halfwords need to be swapped accordingly for
 * little-endian.
 */
#if defined(__nanomips__)
# ifdef __MIPSEL__
#  define RSEQ_SIG	0x03500010
# else
#  define RSEQ_SIG	0x00100350
# endif
#elif defined(__mips_micromips)
# ifdef __MIPSEL__
#  define RSEQ_SIG	0xd4070000
# else
#  define RSEQ_SIG	0x0000d407
# endif
#elif defined(__mips__)
# define RSEQ_SIG	0x0350000d
#else
/* Unknown MIPS architecture. */
#endif

#define rseq_smp_mb()	__asm__ __volatile__ ("sync" ::: "memory")
#define rseq_smp_rmb()	rseq_smp_mb()
#define rseq_smp_wmb()	rseq_smp_mb()

#define rseq_smp_load_acquire(p)					\
__extension__ ({							\
	rseq_unqual_scalar_typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));	\
	rseq_smp_mb();							\
	____p1;								\
})

#define rseq_smp_acquire__after_ctrl_dep()	rseq_smp_rmb()

#define rseq_smp_store_release(p, v)					\
do {									\
	rseq_smp_mb();							\
	RSEQ_WRITE_ONCE(*(p), v);					\
} while (0)

#if _MIPS_SZLONG == 64
# define LONG			".dword"
# define LONG_LA		"dla"
# define LONG_L			"ld"
# define LONG_S			"sd"
# define LONG_ADDI		"daddiu"
# define U32_U64_PAD(x)		x
#elif _MIPS_SZLONG == 32
# define LONG			".word"
# define LONG_LA		"la"
# define LONG_L			"lw"
# define LONG_S			"sw"
# define LONG_ADDI		"addiu"
# ifdef __BIG_ENDIAN
#  define U32_U64_PAD(x)	"0x0, " x
# else
#  define U32_U64_PAD(x)	x ", 0x0"
# endif
#else
# error unsupported _MIPS_SZLONG
#endif

#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip, \
				post_commit_offset, abort_ip) \
		".pushsection __rseq_cs, \"aw\"\n\t" \
		".balign 32\n\t" \
		__rseq_str(label) ":\n\t"					\
		".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \
		".popsection\n\t" \
		".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(label) "b") "\n\t" \
		".popsection\n\t"

#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \
	__RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \
				(post_commit_ip - start_ip), abort_ip)

/*
 * Exit points of a rseq critical section consist of all instructions outside
 * of the critical section where a critical section can either branch to or
 * reach through the normal course of its execution. The abort IP and the
 * post-commit IP are already part of the __rseq_cs section and should not be
 * explicitly defined as additional exit points. Knowing all exit points is
 * useful to assist debuggers stepping over the critical section.
 */
#define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \
		".pushsection __rseq_exit_point_array, \"aw\"\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(exit_ip)) "\n\t" \
		".popsection\n\t"

#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
		RSEQ_INJECT_ASM(1) \
		LONG_LA " $4, " __rseq_str(cs_label) "\n\t" \
		LONG_S  " $4, %[" __rseq_str(rseq_cs) "]\n\t" \
		__rseq_str(label) ":\n\t"

#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
		RSEQ_INJECT_ASM(2) \
		"lw  $4, %[" __rseq_str(current_cpu_id) "]\n\t" \
		"bne $4, %[" __rseq_str(cpu_id) "], " __rseq_str(label) "\n\t"

#define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \
				abort_label, version, flags, \
				start_ip, post_commit_offset, abort_ip) \
		".balign 32\n\t" \
		__rseq_str(table_label) ":\n\t" \
		".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \
		LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \
		".word " __rseq_str(RSEQ_SIG) "\n\t" \
		__rseq_str(label) ":\n\t" \
		teardown \
		"b %l[" __rseq_str(abort_label) "]\n\t"

#define RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, abort_label, \
			      start_ip, post_commit_ip, abort_ip) \
	__RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \
				abort_label, 0x0, 0x0, start_ip, \
				(post_commit_ip - start_ip), abort_ip)

#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \
		__rseq_str(label) ":\n\t" \
		teardown \
		"b %l[" __rseq_str(cmpfail_label) "]\n\t"

/* Per-cpu-id indexing. */

#define RSEQ_TEMPLATE_CPU_ID
#define RSEQ_TEMPLATE_MO_RELAXED
#include "rseq-mips-bits.h"
#undef RSEQ_TEMPLATE_MO_RELAXED

#define RSEQ_TEMPLATE_MO_RELEASE
#include "rseq-mips-bits.h"
#undef RSEQ_TEMPLATE_MO_RELEASE
#undef RSEQ_TEMPLATE_CPU_ID

/* Per-mm-cid indexing. */

#define RSEQ_TEMPLATE_MM_CID
#define RSEQ_TEMPLATE_MO_RELAXED
#include "rseq-mips-bits.h"
#undef RSEQ_TEMPLATE_MO_RELAXED

#define RSEQ_TEMPLATE_MO_RELEASE
#include "rseq-mips-bits.h"
#undef RSEQ_TEMPLATE_MO_RELEASE
#undef RSEQ_TEMPLATE_MM_CID

/* APIs which are not based on cpu ids. */

#define RSEQ_TEMPLATE_CPU_ID_NONE
#define RSEQ_TEMPLATE_MO_RELAXED
#include "rseq-mips-bits.h"
#undef RSEQ_TEMPLATE_MO_RELAXED
#undef RSEQ_TEMPLATE_CPU_ID_NONE