From b9c87f536c6f28c75ace8a014646faad00f0e1ec Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Tue, 12 Dec 2023 16:13:09 -0800 Subject: perf annotate-data: Add find_data_type() to get type from memory access The find_data_type() is to get a data type from the memory access at the given address (IP) using a register and an offset. It requires DWARF debug info in the DSO and searches the list of variables and function parameters in the scope. In a pseudo code, it does basically the following: find_data_type(dso, ip, reg, offset) { pc = map__rip_2objdump(ip); CU = dwarf_addrdie(dso->dwarf, pc); scopes = die_get_scopes(CU, pc); for_each_scope(S, scopes) { V = die_find_variable_by_reg(S, pc, reg); if (V && V.type == pointer_type) { T = die_get_real_type(V); if (offset < T.size) return T; } } return NULL; } Committer notes: The 'size' variable in check_variable() is 64-bit, so use PRIu64 and inttypes.h to debug it. Ditto at find_data_type_die(). Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Stephane Eranian Cc: linux-toolchains@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Link: https://lore.kernel.org/r/20231213001323.718046-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/annotate-data.h | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 tools/perf/util/annotate-data.h (limited to 'tools/perf/util/annotate-data.h') diff --git a/tools/perf/util/annotate-data.h b/tools/perf/util/annotate-data.h new file mode 100644 index 000000000000..633147f78ca5 --- /dev/null +++ b/tools/perf/util/annotate-data.h @@ -0,0 +1,40 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _PERF_ANNOTATE_DATA_H +#define _PERF_ANNOTATE_DATA_H + +#include +#include +#include + +struct map_symbol; + +/** + * struct annotated_data_type - Data type to profile + * @type_name: Name of the data type + * @type_size: Size of the data type + * + * This represents a data type accessed by samples in the profile data. + */ +struct annotated_data_type { + char *type_name; + int type_size; +}; + +#ifdef HAVE_DWARF_SUPPORT + +/* Returns data type at the location (ip, reg, offset) */ +struct annotated_data_type *find_data_type(struct map_symbol *ms, u64 ip, + int reg, int offset); + +#else /* HAVE_DWARF_SUPPORT */ + +static inline struct annotated_data_type * +find_data_type(struct map_symbol *ms __maybe_unused, u64 ip __maybe_unused, + int reg __maybe_unused, int offset __maybe_unused) +{ + return NULL; +} + +#endif /* HAVE_DWARF_SUPPORT */ + +#endif /* _PERF_ANNOTATE_DATA_H */ -- cgit v1.2.3