From 8b1e1a0347ea299b038f83dcfcd799508aa42d68 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Mon, 4 Jul 2022 17:27:21 +0200 Subject: [PATCH] perf bpf: Convert legacy map definition to BTF-defined The libbpf is switching off support for legacy map definitions [1], which will break the perf llvm tests. Moving the base source map definition to BTF-defined, so we need to use -g compile option for to add debug/BTF info. [1] https://lore.kernel.org/bpf/20220627211527.2245459-1-andrii@kernel.org/ Signed-off-by: Jiri Olsa Acked-by: Andrii Nakryiko Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20220704152721.352046-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/tests/bpf-script-example.c | 35 +++++++++++++++++++++++------------ tools/perf/util/llvm-utils.c | 2 +- 2 files changed, 24 insertions(+), 13 deletions(-) diff --git a/tools/perf/tests/bpf-script-example.c b/tools/perf/tests/bpf-script-example.c index ab4b98b3..7981c69 100644 --- a/tools/perf/tests/bpf-script-example.c +++ b/tools/perf/tests/bpf-script-example.c @@ -17,20 +17,31 @@ static void *(*bpf_map_lookup_elem)(void *map, void *key) = static void *(*bpf_map_update_elem)(void *map, void *key, void *value, int flags) = (void *) BPF_FUNC_map_update_elem; -struct bpf_map_def { - unsigned int type; - unsigned int key_size; - unsigned int value_size; - unsigned int max_entries; -}; +/* + * Following macros are taken from tools/lib/bpf/bpf_helpers.h, + * and are used to create BTF defined maps. It is easier to take + * 2 simple macros, than being able to include above header in + * runtime. + * + * __uint - defines integer attribute of BTF map definition, + * Such attributes are represented using a pointer to an array, + * in which dimensionality of array encodes specified integer + * value. + * + * __type - defines pointer variable with typeof(val) type for + * attributes like key or value, which will be defined by the + * size of the type. + */ +#define __uint(name, val) int (*name)[val] +#define __type(name, val) typeof(val) *name #define SEC(NAME) __attribute__((section(NAME), used)) -struct bpf_map_def SEC("maps") flip_table = { - .type = BPF_MAP_TYPE_ARRAY, - .key_size = sizeof(int), - .value_size = sizeof(int), - .max_entries = 1, -}; +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 1); + __type(key, int); + __type(value, int); +} flip_table SEC(".maps"); SEC("func=do_epoll_wait") int bpf_func__SyS_epoll_pwait(void *ctx) diff --git a/tools/perf/util/llvm-utils.c b/tools/perf/util/llvm-utils.c index 96c8ef6..2dc7970 100644 --- a/tools/perf/util/llvm-utils.c +++ b/tools/perf/util/llvm-utils.c @@ -25,7 +25,7 @@ "$CLANG_OPTIONS $PERF_BPF_INC_OPTIONS $KERNEL_INC_OPTIONS " \ "-Wno-unused-value -Wno-pointer-sign " \ "-working-directory $WORKING_DIR " \ - "-c \"$CLANG_SOURCE\" -target bpf $CLANG_EMIT_LLVM -O2 -o - $LLVM_OPTIONS_PIPE" + "-c \"$CLANG_SOURCE\" -target bpf $CLANG_EMIT_LLVM -g -O2 -o - $LLVM_OPTIONS_PIPE" struct llvm_param llvm_param = { .clang_path = "clang", -- 2.7.4