From e01a75c159691714607b8a22daa2ba7be275dd01 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 8 Oct 2019 10:59:40 -0700 Subject: libbpf: Move bpf_{helpers, helper_defs, endian, tracing}.h into libbpf Move bpf_helpers.h, bpf_tracing.h, and bpf_endian.h into libbpf. Move bpf_helper_defs.h generation into libbpf's Makefile. Ensure all those headers are installed along the other libbpf headers. Also, adjust selftests and samples include path to include libbpf now. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20191008175942.1769476-6-andriin@fb.com --- tools/lib/bpf/bpf_helpers.h | 55 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 tools/lib/bpf/bpf_helpers.h (limited to 'tools/lib/bpf/bpf_helpers.h') diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h new file mode 100644 index 000000000000..6d059c0a7845 --- /dev/null +++ b/tools/lib/bpf/bpf_helpers.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ +#ifndef __BPF_HELPERS__ +#define __BPF_HELPERS__ + +#include "bpf_helper_defs.h" + +#define __uint(name, val) int (*name)[val] +#define __type(name, val) typeof(val) *name + +/* helper macro to print out debug messages */ +#define bpf_printk(fmt, ...) \ +({ \ + char ____fmt[] = fmt; \ + bpf_trace_printk(____fmt, sizeof(____fmt), \ + ##__VA_ARGS__); \ +}) + +/* helper macro to place programs, maps, license in + * different sections in elf_bpf file. Section names + * are interpreted by elf_bpf loader + */ +#define SEC(NAME) __attribute__((section(NAME), used)) + +/* a helper structure used by eBPF C program + * to describe BPF map attributes to libbpf loader + */ +struct bpf_map_def { + unsigned int type; + unsigned int key_size; + unsigned int value_size; + unsigned int max_entries; + unsigned int map_flags; +}; + +/* + * bpf_core_read() abstracts away bpf_probe_read() call and captures offset + * relocation for source address using __builtin_preserve_access_index() + * built-in, provided by Clang. + * + * __builtin_preserve_access_index() takes as an argument an expression of + * taking an address of a field within struct/union. It makes compiler emit + * a relocation, which records BTF type ID describing root struct/union and an + * accessor string which describes exact embedded field that was used to take + * an address. See detailed description of this relocation format and + * semantics in comments to struct bpf_offset_reloc in libbpf_internal.h. + * + * This relocation allows libbpf to adjust BPF instruction to use correct + * actual field offset, based on target kernel BTF type that matches original + * (local) BTF, used to record relocation. + */ +#define bpf_core_read(dst, sz, src) \ + bpf_probe_read(dst, sz, \ + (const void *)__builtin_preserve_access_index(src)) + +#endif -- cgit v1.2.3 From 7db3822ab99157e16c41caa5e7d788834d5a3c7c Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 8 Oct 2019 10:59:41 -0700 Subject: libbpf: Add BPF_CORE_READ/BPF_CORE_READ_INTO helpers Add few macros simplifying BCC-like multi-level probe reads, while also emitting CO-RE relocations for each read. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20191008175942.1769476-7-andriin@fb.com --- tools/lib/bpf/bpf_helpers.h | 32 +++++++++----------------------- 1 file changed, 9 insertions(+), 23 deletions(-) (limited to 'tools/lib/bpf/bpf_helpers.h') diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index 6d059c0a7845..2203595f38c3 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -7,7 +7,7 @@ #define __uint(name, val) int (*name)[val] #define __type(name, val) typeof(val) *name -/* helper macro to print out debug messages */ +/* Helper macro to print out debug messages */ #define bpf_printk(fmt, ...) \ ({ \ char ____fmt[] = fmt; \ @@ -15,13 +15,19 @@ ##__VA_ARGS__); \ }) -/* helper macro to place programs, maps, license in +/* + * Helper macro to place programs, maps, license in * different sections in elf_bpf file. Section names * are interpreted by elf_bpf loader */ #define SEC(NAME) __attribute__((section(NAME), used)) -/* a helper structure used by eBPF C program +#ifndef __always_inline +#define __always_inline __attribute__((always_inline)) +#endif + +/* + * Helper structure used by eBPF C program * to describe BPF map attributes to libbpf loader */ struct bpf_map_def { @@ -32,24 +38,4 @@ struct bpf_map_def { unsigned int map_flags; }; -/* - * bpf_core_read() abstracts away bpf_probe_read() call and captures offset - * relocation for source address using __builtin_preserve_access_index() - * built-in, provided by Clang. - * - * __builtin_preserve_access_index() takes as an argument an expression of - * taking an address of a field within struct/union. It makes compiler emit - * a relocation, which records BTF type ID describing root struct/union and an - * accessor string which describes exact embedded field that was used to take - * an address. See detailed description of this relocation format and - * semantics in comments to struct bpf_offset_reloc in libbpf_internal.h. - * - * This relocation allows libbpf to adjust BPF instruction to use correct - * actual field offset, based on target kernel BTF type that matches original - * (local) BTF, used to record relocation. - */ -#define bpf_core_read(dst, sz, src) \ - bpf_probe_read(dst, sz, \ - (const void *)__builtin_preserve_access_index(src)) - #endif -- cgit v1.2.3 From 57a00f41644f20b11c12a27061d814655f633544 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= Date: Sat, 2 Nov 2019 12:09:41 +0100 Subject: libbpf: Add auto-pinning of maps when loading BPF objects MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds support to libbpf for setting map pinning information as part of the BTF map declaration, to get automatic map pinning (and reuse) on load. The pinning type currently only supports a single PIN_BY_NAME mode, where each map will be pinned by its name in a path that can be overridden, but defaults to /sys/fs/bpf. Since auto-pinning only does something if any maps actually have a 'pinning' BTF attribute set, we default the new option to enabled, on the assumption that seamless pinning is what most callers want. When a map has a pin_path set at load time, libbpf will compare the map pinned at that location (if any), and if the attributes match, will re-use that map instead of creating a new one. If no existing map is found, the newly created map will instead be pinned at the location. Programs wanting to customise the pinning can override the pinning paths using bpf_map__set_pin_path() before calling bpf_object__load() (including setting it to NULL to disable pinning of a particular map). Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/157269298092.394725.3966306029218559681.stgit@toke.dk --- tools/lib/bpf/bpf_helpers.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'tools/lib/bpf/bpf_helpers.h') diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index 2203595f38c3..0c7d28292898 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -38,4 +38,10 @@ struct bpf_map_def { unsigned int map_flags; }; +enum libbpf_pin_type { + LIBBPF_PIN_NONE, + /* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */ + LIBBPF_PIN_BY_NAME, +}; + #endif -- cgit v1.2.3 From 11d1e2eefffe86339b3b0b773bd31ef3b88faf7d Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 14 Nov 2019 10:57:09 -0800 Subject: selftests/bpf: Add test for BPF trampoline Add sanity test for BPF trampoline that checks kernel functions with up to 6 arguments of different sizes. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20191114185720.1641606-10-ast@kernel.org --- tools/lib/bpf/bpf_helpers.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'tools/lib/bpf/bpf_helpers.h') diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index 0c7d28292898..c63ab1add126 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -44,4 +44,17 @@ enum libbpf_pin_type { LIBBPF_PIN_BY_NAME, }; +/* The following types should be used by BPF_PROG_TYPE_TRACING program to + * access kernel function arguments. BPF trampoline and raw tracepoints + * typecast arguments to 'unsigned long long'. + */ +typedef int __attribute__((aligned(8))) ks32; +typedef char __attribute__((aligned(8))) ks8; +typedef short __attribute__((aligned(8))) ks16; +typedef long long __attribute__((aligned(8))) ks64; +typedef unsigned int __attribute__((aligned(8))) ku32; +typedef unsigned char __attribute__((aligned(8))) ku8; +typedef unsigned short __attribute__((aligned(8))) ku16; +typedef unsigned long long __attribute__((aligned(8))) ku64; + #endif -- cgit v1.2.3 From f9a7cf6eb17cd0110c8c47d9e7969fc2716e5772 Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Sat, 23 Nov 2019 12:25:04 -0800 Subject: bpf: Introduce BPF_TRACE_x helper for the tracing tests For BPF_PROG_TYPE_TRACING, the bpf_prog's ctx is an array of u64. This patch borrows the idea from BPF_CALL_x in filter.h to convert a u64 to the arg type of the traced function. The new BPF_TRACE_x has an arg to specify the return type of a bpf_prog. It will be used in the future TCP-ops bpf_prog that may return "void". The new macros are defined in the new header file "bpf_trace_helpers.h". It is under selftests/bpf/ for now. It could be moved to libbpf later after seeing more upcoming non-tracing use cases. The tests are changed to use these new macros also. Hence, the k[s]u8/16/32/64 are no longer needed and they are removed from the bpf_helpers.h. Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20191123202504.1502696-1-kafai@fb.com --- tools/lib/bpf/bpf_helpers.h | 13 ------------- 1 file changed, 13 deletions(-) (limited to 'tools/lib/bpf/bpf_helpers.h') diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h index c63ab1add126..0c7d28292898 100644 --- a/tools/lib/bpf/bpf_helpers.h +++ b/tools/lib/bpf/bpf_helpers.h @@ -44,17 +44,4 @@ enum libbpf_pin_type { LIBBPF_PIN_BY_NAME, }; -/* The following types should be used by BPF_PROG_TYPE_TRACING program to - * access kernel function arguments. BPF trampoline and raw tracepoints - * typecast arguments to 'unsigned long long'. - */ -typedef int __attribute__((aligned(8))) ks32; -typedef char __attribute__((aligned(8))) ks8; -typedef short __attribute__((aligned(8))) ks16; -typedef long long __attribute__((aligned(8))) ks64; -typedef unsigned int __attribute__((aligned(8))) ku32; -typedef unsigned char __attribute__((aligned(8))) ku8; -typedef unsigned short __attribute__((aligned(8))) ku16; -typedef unsigned long long __attribute__((aligned(8))) ku64; - #endif -- cgit v1.2.3