Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2
3#undef TRACE_SYSTEM_VAR
4
5#ifdef CONFIG_BPF_EVENTS
6
7#include "stages/stage6_event_callback.h"
8
9#undef __perf_count
10#define __perf_count(c) (c)
11
12#undef __perf_task
13#define __perf_task(t) (t)
14
15#include <linux/args.h>
16
17/* cast any integer, pointer, or small struct to u64 */
18#define UINTTYPE(size) \
19 __typeof__(__builtin_choose_expr(size == 1, (u8)1, \
20 __builtin_choose_expr(size == 2, (u16)2, \
21 __builtin_choose_expr(size == 4, (u32)3, \
22 __builtin_choose_expr(size == 8, (u64)4, \
23 (void)5)))))
24#define __CAST_TO_U64(x) ({ \
25 typeof(x) __src = (x); \
26 UINTTYPE(sizeof(x)) __dst; \
27 memcpy(&__dst, &__src, sizeof(__dst)); \
28 (u64)__dst; })
29
30#define __CAST1(a,...) __CAST_TO_U64(a)
31#define __CAST2(a,...) __CAST_TO_U64(a), __CAST1(__VA_ARGS__)
32#define __CAST3(a,...) __CAST_TO_U64(a), __CAST2(__VA_ARGS__)
33#define __CAST4(a,...) __CAST_TO_U64(a), __CAST3(__VA_ARGS__)
34#define __CAST5(a,...) __CAST_TO_U64(a), __CAST4(__VA_ARGS__)
35#define __CAST6(a,...) __CAST_TO_U64(a), __CAST5(__VA_ARGS__)
36#define __CAST7(a,...) __CAST_TO_U64(a), __CAST6(__VA_ARGS__)
37#define __CAST8(a,...) __CAST_TO_U64(a), __CAST7(__VA_ARGS__)
38#define __CAST9(a,...) __CAST_TO_U64(a), __CAST8(__VA_ARGS__)
39#define __CAST10(a,...) __CAST_TO_U64(a), __CAST9(__VA_ARGS__)
40#define __CAST11(a,...) __CAST_TO_U64(a), __CAST10(__VA_ARGS__)
41#define __CAST12(a,...) __CAST_TO_U64(a), __CAST11(__VA_ARGS__)
42/* tracepoints with more than 12 arguments will hit build error */
43#define CAST_TO_U64(...) CONCATENATE(__CAST, COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__)
44
45#define __BPF_DECLARE_TRACE(call, proto, args) \
46static notrace void \
47__bpf_trace_##call(void *__data, proto) \
48{ \
49 CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(__data, CAST_TO_U64(args)); \
50}
51
52#undef DECLARE_EVENT_CLASS
53#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
54 __BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))
55
56#define __BPF_DECLARE_TRACE_SYSCALL(call, proto, args) \
57static notrace void \
58__bpf_trace_##call(void *__data, proto) \
59{ \
60 might_fault(); \
61 preempt_disable_notrace(); \
62 CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(__data, CAST_TO_U64(args)); \
63 preempt_enable_notrace(); \
64}
65
66#undef DECLARE_EVENT_SYSCALL_CLASS
67#define DECLARE_EVENT_SYSCALL_CLASS(call, proto, args, tstruct, assign, print) \
68 __BPF_DECLARE_TRACE_SYSCALL(call, PARAMS(proto), PARAMS(args))
69
70/*
71 * This part is compiled out, it is only here as a build time check
72 * to make sure that if the tracepoint handling changes, the
73 * bpf probe will fail to compile unless it too is updated.
74 */
75#define __DEFINE_EVENT(template, call, proto, args, size) \
76static inline void bpf_test_probe_##call(void) \
77{ \
78 check_trace_callback_type_##call(__bpf_trace_##template); \
79} \
80typedef void (*btf_trace_##call)(void *__data, proto); \
81static union { \
82 struct bpf_raw_event_map event; \
83 btf_trace_##call handler; \
84} __bpf_trace_tp_map_##call __used \
85__section("__bpf_raw_tp_map") = { \
86 .event = { \
87 .tp = &__tracepoint_##call, \
88 .bpf_func = __bpf_trace_##template, \
89 .num_args = COUNT_ARGS(args), \
90 .writable_size = size, \
91 }, \
92};
93
94#define FIRST(x, ...) x
95
96#define __CHECK_WRITABLE_BUF_SIZE(call, proto, args, size) \
97static inline void bpf_test_buffer_##call(void) \
98{ \
99 /* BUILD_BUG_ON() is ignored if the code is completely eliminated, but \
100 * BUILD_BUG_ON_ZERO() uses a different mechanism that is not \
101 * dead-code-eliminated. \
102 */ \
103 FIRST(proto); \
104 (void)BUILD_BUG_ON_ZERO(size != sizeof(*FIRST(args))); \
105}
106
107#undef DEFINE_EVENT_WRITABLE
108#define DEFINE_EVENT_WRITABLE(template, call, proto, args, size) \
109 __CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
110 __DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), size)
111
112#undef DEFINE_EVENT
113#define DEFINE_EVENT(template, call, proto, args) \
114 __DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), 0)
115
116#undef DEFINE_EVENT_PRINT
117#define DEFINE_EVENT_PRINT(template, name, proto, args, print) \
118 DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
119
120#undef DECLARE_TRACE
121#define DECLARE_TRACE(call, proto, args) \
122 __BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args)) \
123 __DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), 0)
124
125#undef DECLARE_TRACE_WRITABLE
126#define DECLARE_TRACE_WRITABLE(call, proto, args, size) \
127 __CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
128 __BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args)) \
129 __DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), size)
130
131#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
132
133#undef DECLARE_TRACE_WRITABLE
134#undef DEFINE_EVENT_WRITABLE
135#undef __CHECK_WRITABLE_BUF_SIZE
136#undef __DEFINE_EVENT
137#undef FIRST
138
139#endif /* CONFIG_BPF_EVENTS */