linux/tools/perf/util/dwarf-aux.h
Yang Jihong 22a665513b perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel
The "address" member of "struct probe_trace_point" uses long data type.
If kernel is 64-bit and perf program is 32-bit, size of "address"
variable is 32 bits.

As a result, upper 32 bits of address read from kernel are truncated, an
error occurs during address comparison in kprobe_warn_out_range().

Before:

  # perf probe -a schedule
  schedule is out of .text, skip it.
    Error: Failed to add events.

Solution:
  Change data type of "address" variable to u64 and change corresponding
address printing and value assignment.

After:

  # perf.new.new probe -a schedule
  Added new event:
    probe:schedule       (on schedule)

  You can now use it in all perf tools, such as:

          perf record -e probe:schedule -aR sleep 1

  # perf probe -l
    probe:schedule       (on schedule@kernel/sched/core.c)
  # perf record -e probe:schedule -aR sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.156 MB perf.data (1366 samples) ]
  # perf report --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 1K of event 'probe:schedule'
  # Event count (approx.): 1366
  #
  # Overhead  Command          Shared Object      Symbol
  # ........  ...............  .................  ............
  #
       6.22%  migration/0      [kernel.kallsyms]  [k] schedule
       6.22%  migration/1      [kernel.kallsyms]  [k] schedule
       6.22%  migration/2      [kernel.kallsyms]  [k] schedule
       6.22%  migration/3      [kernel.kallsyms]  [k] schedule
       6.15%  migration/10     [kernel.kallsyms]  [k] schedule
       6.15%  migration/11     [kernel.kallsyms]  [k] schedule
       6.15%  migration/12     [kernel.kallsyms]  [k] schedule
       6.15%  migration/13     [kernel.kallsyms]  [k] schedule
       6.15%  migration/14     [kernel.kallsyms]  [k] schedule
       6.15%  migration/15     [kernel.kallsyms]  [k] schedule
       6.15%  migration/4      [kernel.kallsyms]  [k] schedule
       6.15%  migration/5      [kernel.kallsyms]  [k] schedule
       6.15%  migration/6      [kernel.kallsyms]  [k] schedule
       6.15%  migration/7      [kernel.kallsyms]  [k] schedule
       6.15%  migration/8      [kernel.kallsyms]  [k] schedule
       6.15%  migration/9      [kernel.kallsyms]  [k] schedule
       0.22%  rcu_sched        [kernel.kallsyms]  [k] schedule
  ...
  #
  # (Cannot load tips.txt file, please install perf!)
  #

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jianlin Lv <jianlin.lv@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/20210715063723.11926-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-07-18 09:31:15 -03:00

131 lines
4.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _DWARF_AUX_H
#define _DWARF_AUX_H
/*
* dwarf-aux.h : libdw auxiliary interfaces
*/
#include <dwarf.h>
#include <elfutils/libdw.h>
#include <elfutils/libdwfl.h>
#include <elfutils/version.h>
struct strbuf;
/* Find the realpath of the target file */
const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname);
/* Get DW_AT_comp_dir (should be NULL with older gcc) */
const char *cu_get_comp_dir(Dwarf_Die *cu_die);
/* Get a line number and file name for given address */
int cu_find_lineinfo(Dwarf_Die *cudie, Dwarf_Addr addr,
const char **fname, int *lineno);
/* Walk on functions at given address */
int cu_walk_functions_at(Dwarf_Die *cu_die, Dwarf_Addr addr,
int (*callback)(Dwarf_Die *, void *), void *data);
/* Get DW_AT_linkage_name (should be NULL for C binary) */
const char *die_get_linkage_name(Dwarf_Die *dw_die);
/* Get the lowest PC in DIE (including range list) */
int die_entrypc(Dwarf_Die *dw_die, Dwarf_Addr *addr);
/* Ensure that this DIE is a subprogram and definition (not declaration) */
bool die_is_func_def(Dwarf_Die *dw_die);
/* Ensure that this DIE is an instance of a subprogram */
bool die_is_func_instance(Dwarf_Die *dw_die);
/* Compare diename and tname */
bool die_compare_name(Dwarf_Die *dw_die, const char *tname);
/* Matching diename with glob pattern */
bool die_match_name(Dwarf_Die *dw_die, const char *glob);
/* Get callsite line number of inline-function instance */
int die_get_call_lineno(Dwarf_Die *in_die);
/* Get callsite file name of inlined function instance */
const char *die_get_call_file(Dwarf_Die *in_die);
/* Get type die */
Dwarf_Die *die_get_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem);
/* Get a type die, but skip qualifiers and typedef */
Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem);
/* Check whether the DIE is signed or not */
bool die_is_signed_type(Dwarf_Die *tp_die);
/* Get data_member_location offset */
int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs);
/* Return values for die_find_child() callbacks */
enum {
DIE_FIND_CB_END = 0, /* End of Search */
DIE_FIND_CB_CHILD = 1, /* Search only children */
DIE_FIND_CB_SIBLING = 2, /* Search only siblings */
DIE_FIND_CB_CONTINUE = 3, /* Search children and siblings */
};
/* Search child DIEs */
Dwarf_Die *die_find_child(Dwarf_Die *rt_die,
int (*callback)(Dwarf_Die *, void *),
void *data, Dwarf_Die *die_mem);
/* Search a non-inlined function including given address */
Dwarf_Die *die_find_realfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
Dwarf_Die *die_mem);
/* Search a non-inlined function with tail call at given address */
Dwarf_Die *die_find_tailfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
Dwarf_Die *die_mem);
/* Search the top inlined function including given address */
Dwarf_Die *die_find_top_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
Dwarf_Die *die_mem);
/* Search the deepest inlined function including given address */
Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
Dwarf_Die *die_mem);
/* Walk on the instances of given DIE */
int die_walk_instances(Dwarf_Die *in_die,
int (*callback)(Dwarf_Die *, void *), void *data);
/* Walker on lines (Note: line number will not be sorted) */
typedef int (* line_walk_callback_t) (const char *fname, int lineno,
Dwarf_Addr addr, void *data);
/*
* Walk on lines inside given DIE. If the DIE is a subprogram, walk only on
* the lines inside the subprogram, otherwise the DIE must be a CU DIE.
*/
int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, void *data);
/* Find a variable called 'name' at given address */
Dwarf_Die *die_find_variable_at(Dwarf_Die *sp_die, const char *name,
Dwarf_Addr addr, Dwarf_Die *die_mem);
/* Find a member called 'name' */
Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name,
Dwarf_Die *die_mem);
/* Get the name of given variable DIE */
int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf);
/* Get the name and type of given variable DIE, stored as "type\tname" */
int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf);
int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf);
/* Check if target program is compiled with optimization */
bool die_is_optimized_target(Dwarf_Die *cu_die);
/* Use next address after prologue as probe location */
void die_skip_prologue(Dwarf_Die *sp_die, Dwarf_Die *cu_die,
Dwarf_Addr *entrypc);
#endif