Commit a93e0b23 authored Apr 16, 2019 by Song Liu Committed by Arnaldo Carvalho de Melo Apr 17, 2019

perf tools: Check maps for bpf programs

As reported by Jiri Olsa in:

  "[BUG] perf: intel_pt won't display kernel function"
  https://lore.kernel.org/lkml/20190403143738.GB32001@krava



Recent changes to support PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT
broke --kallsyms option. This is because it broke test __map__is_kmodule.

This patch fixes this by adding check for bpf program, so that these maps
are not mistaken as kernel modules.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reported-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yonghong Song <yhs@fb.com>
Link: http://lkml.kernel.org/r/20190416160127.30203-8-jolsa@kernel.org


Fixes: 76193a94 ("perf, bpf: Introduce PERF_RECORD_KSYMBOL")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent aa526602

tools/perf/util/map.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -261,6 +261,22 @@ bool __map__is_extra_kernel_map(const struct map *map)
		return kmap && kmap->name[0];
		}

		bool __map__is_bpf_prog(const struct map *map)
		{
		const char *name;

		if (map->dso->binary_type == DSO_BINARY_TYPE__BPF_PROG_INFO)
		return true;

		/*
		* If PERF_RECORD_BPF_EVENT is not included, the dso will not have
		* type of DSO_BINARY_TYPE__BPF_PROG_INFO. In such cases, we can
		* guess the type based on name.
		*/
		name = map->dso->short_name;
		return name && (strstr(name, "bpf_prog_") == name);
		}

		bool map__has_symbols(const struct map *map)
		{
		return dso__has_symbols(map->dso);

tools/perf/util/map.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -159,10 +159,12 @@ int map__set_kallsyms_ref_reloc_sym(struct map map, const char symbol_name,

		bool __map__is_kernel(const struct map *map);
		bool __map__is_extra_kernel_map(const struct map *map);
		bool __map__is_bpf_prog(const struct map *map);

		static inline bool __map__is_kmodule(const struct map *map)
		{
		return !__map__is_kernel(map) && !__map__is_extra_kernel_map(map);
		return !__map__is_kernel(map) && !__map__is_extra_kernel_map(map) &&
		!__map__is_bpf_prog(map);
		}

		bool map__has_symbols(const struct map *map);

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