Commit df8ff353 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Alexei Starovoitov
Browse files

libbpf: Merge selftests' bpf_trace_helpers.h into libbpf's bpf_tracing.h 



Move BPF_PROG, BPF_KPROBE, and BPF_KRETPROBE macro into libbpf's bpf_tracing.h
header to make it available for non-selftests users.

Signed-off-by: default avatarAndrii Nakryiko <andriin@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200229231112.1240137-5-andriin@fb.com
parent 396f544e

tools/lib/bpf/bpf_tracing.h

+118 −0
Original line number Diff line number Diff line
@@ -192,4 +192,122 @@ struct pt_regs; 
			  (void *)(PT_REGS_FP(ctx) + sizeof(ip))); })

#endif



#define ___bpf_concat(a, b) a ## b

#define ___bpf_apply(fn, n) ___bpf_concat(fn, n)

#define ___bpf_nth(_, _1, _2, _3, _4, _5, _6, _7, _8, _9, _a, _b, _c, N, ...) N

#define ___bpf_narg(...) \

	___bpf_nth(_, ##__VA_ARGS__, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)

#define ___bpf_empty(...) \

	___bpf_nth(_, ##__VA_ARGS__, N, N, N, N, N, N, N, N, N, N, 0)



#define ___bpf_ctx_cast0() ctx

#define ___bpf_ctx_cast1(x) ___bpf_ctx_cast0(), (void *)ctx[0]

#define ___bpf_ctx_cast2(x, args...) ___bpf_ctx_cast1(args), (void *)ctx[1]

#define ___bpf_ctx_cast3(x, args...) ___bpf_ctx_cast2(args), (void *)ctx[2]

#define ___bpf_ctx_cast4(x, args...) ___bpf_ctx_cast3(args), (void *)ctx[3]

#define ___bpf_ctx_cast5(x, args...) ___bpf_ctx_cast4(args), (void *)ctx[4]

#define ___bpf_ctx_cast6(x, args...) ___bpf_ctx_cast5(args), (void *)ctx[5]

#define ___bpf_ctx_cast7(x, args...) ___bpf_ctx_cast6(args), (void *)ctx[6]

#define ___bpf_ctx_cast8(x, args...) ___bpf_ctx_cast7(args), (void *)ctx[7]

#define ___bpf_ctx_cast9(x, args...) ___bpf_ctx_cast8(args), (void *)ctx[8]

#define ___bpf_ctx_cast10(x, args...) ___bpf_ctx_cast9(args), (void *)ctx[9]

#define ___bpf_ctx_cast11(x, args...) ___bpf_ctx_cast10(args), (void *)ctx[10]

#define ___bpf_ctx_cast12(x, args...) ___bpf_ctx_cast11(args), (void *)ctx[11]

#define ___bpf_ctx_cast(args...) \

	___bpf_apply(___bpf_ctx_cast, ___bpf_narg(args))(args)



/*

 * BPF_PROG is a convenience wrapper for generic tp_btf/fentry/fexit and

 * similar kinds of BPF programs, that accept input arguments as a single

 * pointer to untyped u64 array, where each u64 can actually be a typed

 * pointer or integer of different size. Instead of requring user to write

 * manual casts and work with array elements by index, BPF_PROG macro

 * allows user to declare a list of named and typed input arguments in the

 * same syntax as for normal C function. All the casting is hidden and

 * performed transparently, while user code can just assume working with

 * function arguments of specified type and name.

 *

 * Original raw context argument is preserved as well as 'ctx' argument.

 * This is useful when using BPF helpers that expect original context

 * as one of the parameters (e.g., for bpf_perf_event_output()).

 */

#define BPF_PROG(name, args...)						    \

name(unsigned long long *ctx);						    \

static __attribute__((always_inline)) typeof(name(0))			    \

____##name(unsigned long long *ctx, ##args);				    \

typeof(name(0)) name(unsigned long long *ctx)				    \

{									    \

	_Pragma("GCC diagnostic push")					    \

	_Pragma("GCC diagnostic ignored \"-Wint-conversion\"")		    \

	return ____##name(___bpf_ctx_cast(args));			    \

	_Pragma("GCC diagnostic pop")					    \

}									    \

static __attribute__((always_inline)) typeof(name(0))			    \

____##name(unsigned long long *ctx, ##args)



struct pt_regs;



#define ___bpf_kprobe_args0() ctx

#define ___bpf_kprobe_args1(x) \

	___bpf_kprobe_args0(), (void *)PT_REGS_PARM1(ctx)

#define ___bpf_kprobe_args2(x, args...) \

	___bpf_kprobe_args1(args), (void *)PT_REGS_PARM2(ctx)

#define ___bpf_kprobe_args3(x, args...) \

	___bpf_kprobe_args2(args), (void *)PT_REGS_PARM3(ctx)

#define ___bpf_kprobe_args4(x, args...) \

	___bpf_kprobe_args3(args), (void *)PT_REGS_PARM4(ctx)

#define ___bpf_kprobe_args5(x, args...) \

	___bpf_kprobe_args4(args), (void *)PT_REGS_PARM5(ctx)

#define ___bpf_kprobe_args(args...) \

	___bpf_apply(___bpf_kprobe_args, ___bpf_narg(args))(args)



/*

 * BPF_KPROBE serves the same purpose for kprobes as BPF_PROG for

 * tp_btf/fentry/fexit BPF programs. It hides the underlying platform-specific

 * low-level way of getting kprobe input arguments from struct pt_regs, and

 * provides a familiar typed and named function arguments syntax and

 * semantics of accessing kprobe input paremeters.

 *

 * Original struct pt_regs* context is preserved as 'ctx' argument. This might

 * be necessary when using BPF helpers like bpf_perf_event_output().

 */

#define BPF_KPROBE(name, args...)					    \

name(struct pt_regs *ctx);						    \

static __attribute__((always_inline)) typeof(name(0))			    \

____##name(struct pt_regs *ctx, ##args);				    \

typeof(name(0)) name(struct pt_regs *ctx)				    \

{									    \

	_Pragma("GCC diagnostic push")					    \

	_Pragma("GCC diagnostic ignored \"-Wint-conversion\"")		    \

	return ____##name(___bpf_kprobe_args(args));			    \

	_Pragma("GCC diagnostic pop")					    \

}									    \

static __attribute__((always_inline)) typeof(name(0))			    \

____##name(struct pt_regs *ctx, ##args)



#define ___bpf_kretprobe_args0() ctx

#define ___bpf_kretprobe_args1(x) \

	___bpf_kretprobe_args0(), (void *)PT_REGS_RET(ctx)

#define ___bpf_kretprobe_args(args...) \

	___bpf_apply(___bpf_kretprobe_args, ___bpf_narg(args))(args)



/*

 * BPF_KRETPROBE is similar to BPF_KPROBE, except, it only provides optional

 * return value (in addition to `struct pt_regs *ctx`), but no input

 * arguments, because they will be clobbered by the time probed function

 * returns.

 */

#define BPF_KRETPROBE(name, args...)					    \

name(struct pt_regs *ctx);						    \

static __attribute__((always_inline)) typeof(name(0))			    \

____##name(struct pt_regs *ctx, ##args);				    \

typeof(name(0)) name(struct pt_regs *ctx)				    \

{									    \

	_Pragma("GCC diagnostic push")					    \

	_Pragma("GCC diagnostic ignored \"-Wint-conversion\"")		    \

	return ____##name(___bpf_kretprobe_args(args));			    \

	_Pragma("GCC diagnostic pop")					    \

}									    \

static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args)



#endif

tools/testing/selftests/bpf/bpf_tcp_helpers.h

+1 −1
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ 
#include <linux/types.h>

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_core_read.h>

#include "bpf_trace_helpers.h"

#include <bpf/bpf_tracing.h>



#define BPF_STRUCT_OPS(name, args...) \

SEC("struct_ops/"#name) \

tools/testing/selftests/bpf/bpf_trace_helpers.h

deleted100644 → 0
+0 −121
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */

#ifndef __BPF_TRACE_HELPERS_H

#define __BPF_TRACE_HELPERS_H



#include <bpf/bpf_helpers.h>



#define ___bpf_concat(a, b) a ## b

#define ___bpf_apply(fn, n) ___bpf_concat(fn, n)

#define ___bpf_nth(_, _1, _2, _3, _4, _5, _6, _7, _8, _9, _a, _b, _c, N, ...) N

#define ___bpf_narg(...) \

	___bpf_nth(_, ##__VA_ARGS__, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)

#define ___bpf_empty(...) \

	___bpf_nth(_, ##__VA_ARGS__, N, N, N, N, N, N, N, N, N, N, 0)



#define ___bpf_ctx_cast0() ctx

#define ___bpf_ctx_cast1(x) ___bpf_ctx_cast0(), (void *)ctx[0]

#define ___bpf_ctx_cast2(x, args...) ___bpf_ctx_cast1(args), (void *)ctx[1]

#define ___bpf_ctx_cast3(x, args...) ___bpf_ctx_cast2(args), (void *)ctx[2]

#define ___bpf_ctx_cast4(x, args...) ___bpf_ctx_cast3(args), (void *)ctx[3]

#define ___bpf_ctx_cast5(x, args...) ___bpf_ctx_cast4(args), (void *)ctx[4]

#define ___bpf_ctx_cast6(x, args...) ___bpf_ctx_cast5(args), (void *)ctx[5]

#define ___bpf_ctx_cast7(x, args...) ___bpf_ctx_cast6(args), (void *)ctx[6]

#define ___bpf_ctx_cast8(x, args...) ___bpf_ctx_cast7(args), (void *)ctx[7]

#define ___bpf_ctx_cast9(x, args...) ___bpf_ctx_cast8(args), (void *)ctx[8]

#define ___bpf_ctx_cast10(x, args...) ___bpf_ctx_cast9(args), (void *)ctx[9]

#define ___bpf_ctx_cast11(x, args...) ___bpf_ctx_cast10(args), (void *)ctx[10]

#define ___bpf_ctx_cast12(x, args...) ___bpf_ctx_cast11(args), (void *)ctx[11]

#define ___bpf_ctx_cast(args...) \

	___bpf_apply(___bpf_ctx_cast, ___bpf_narg(args))(args)



/*

 * BPF_PROG is a convenience wrapper for generic tp_btf/fentry/fexit and

 * similar kinds of BPF programs, that accept input arguments as a single

 * pointer to untyped u64 array, where each u64 can actually be a typed

 * pointer or integer of different size. Instead of requring user to write

 * manual casts and work with array elements by index, BPF_PROG macro

 * allows user to declare a list of named and typed input arguments in the

 * same syntax as for normal C function. All the casting is hidden and

 * performed transparently, while user code can just assume working with

 * function arguments of specified type and name.

 *

 * Original raw context argument is preserved as well as 'ctx' argument.

 * This is useful when using BPF helpers that expect original context

 * as one of the parameters (e.g., for bpf_perf_event_output()).

 */

#define BPF_PROG(name, args...)						    \

name(unsigned long long *ctx);						    \

static __always_inline typeof(name(0))					    \

____##name(unsigned long long *ctx, ##args);				    \

typeof(name(0)) name(unsigned long long *ctx)				    \

{									    \

	_Pragma("GCC diagnostic push")					    \

	_Pragma("GCC diagnostic ignored \"-Wint-conversion\"")		    \

	return ____##name(___bpf_ctx_cast(args));			    \

	_Pragma("GCC diagnostic pop")					    \

}									    \

static __always_inline typeof(name(0))					    \

____##name(unsigned long long *ctx, ##args)



struct pt_regs;



#define ___bpf_kprobe_args0() ctx

#define ___bpf_kprobe_args1(x) \

	___bpf_kprobe_args0(), (void *)PT_REGS_PARM1(ctx)

#define ___bpf_kprobe_args2(x, args...) \

	___bpf_kprobe_args1(args), (void *)PT_REGS_PARM2(ctx)

#define ___bpf_kprobe_args3(x, args...) \

	___bpf_kprobe_args2(args), (void *)PT_REGS_PARM3(ctx)

#define ___bpf_kprobe_args4(x, args...) \

	___bpf_kprobe_args3(args), (void *)PT_REGS_PARM4(ctx)

#define ___bpf_kprobe_args5(x, args...) \

	___bpf_kprobe_args4(args), (void *)PT_REGS_PARM5(ctx)

#define ___bpf_kprobe_args(args...) \

	___bpf_apply(___bpf_kprobe_args, ___bpf_narg(args))(args)



/*

 * BPF_KPROBE serves the same purpose for kprobes as BPF_PROG for

 * tp_btf/fentry/fexit BPF programs. It hides the underlying platform-specific

 * low-level way of getting kprobe input arguments from struct pt_regs, and

 * provides a familiar typed and named function arguments syntax and

 * semantics of accessing kprobe input paremeters.

 *

 * Original struct pt_regs* context is preserved as 'ctx' argument. This might

 * be necessary when using BPF helpers like bpf_perf_event_output().

 */

#define BPF_KPROBE(name, args...)					    \

name(struct pt_regs *ctx);						    \

static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args);\

typeof(name(0)) name(struct pt_regs *ctx)				    \

{									    \

	_Pragma("GCC diagnostic push")					    \

	_Pragma("GCC diagnostic ignored \"-Wint-conversion\"")		    \

	return ____##name(___bpf_kprobe_args(args));			    \

	_Pragma("GCC diagnostic pop")					    \

}									    \

static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args)



#define ___bpf_kretprobe_args0() ctx

#define ___bpf_kretprobe_args1(x) \

	___bpf_kretprobe_args0(), (void *)PT_REGS_RET(ctx)

#define ___bpf_kretprobe_args(args...) \

	___bpf_apply(___bpf_kretprobe_args, ___bpf_narg(args))(args)



/*

 * BPF_KRETPROBE is similar to BPF_KPROBE, except, it only provides optional

 * return value (in addition to `struct pt_regs *ctx`), but no input

 * arguments, because they will be clobbered by the time probed function

 * returns.

 */

#define BPF_KRETPROBE(name, args...)					    \

name(struct pt_regs *ctx);						    \

static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args);\

typeof(name(0)) name(struct pt_regs *ctx)				    \

{									    \

	_Pragma("GCC diagnostic push")					    \

	_Pragma("GCC diagnostic ignored \"-Wint-conversion\"")		    \

	return ____##name(___bpf_kretprobe_args(args));			    \

	_Pragma("GCC diagnostic pop")					    \

}									    \

static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args)

#endif

tools/testing/selftests/bpf/progs/bpf_dctcp.c

+1 −1
Original line number Diff line number Diff line
@@ -9,7 +9,7 @@ 
#include <linux/bpf.h>

#include <linux/types.h>

#include <bpf/bpf_helpers.h>

#include "bpf_trace_helpers.h"

#include <bpf/bpf_tracing.h>

#include "bpf_tcp_helpers.h"



char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/fentry_test.c

+1 −1
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 
/* Copyright (c) 2019 Facebook */

#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>

#include "bpf_trace_helpers.h"

#include <bpf/bpf_tracing.h>



char _license[] SEC("license") = "GPL";