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