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authorMasami Hiramatsu <mhiramat@kernel.org>2019-10-24 18:12:54 +0900
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-01-04 13:34:23 +0100
commit2574108dd2d8528e6b28af78a145658c71da7630 (patch)
treee80b1ae905f047b26cb8f1b7e97ae12ed0ac80ca /tools
parent53644aeb8336fc8f1f797525d3fac09942433f6c (diff)
perf probe: Fix to show function entry line as probe-able
commit 91e2f539eeda26ab00bd03fae8dc434c128c85ed upstream. Fix die_walk_lines() to list the function entry line correctly. Since the dwarf_entrypc() does not return the entry pc if the DIE has only range attribute, __die_walk_funclines() fails to list the declaration line (entry line) in that case. To solve this issue, this introduces die_entrypc() which correctly returns the entry PC (the first address range) even if the DIE has only range attribute. With this fix die_walk_lines() shows the function entry line is able to probe correctly. Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lore.kernel.org/lkml/157190837419.1859.4619125803596816752.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Thomas Backlund <tmb@mageia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools')
-rw-r--r--tools/perf/util/dwarf-aux.c24
-rw-r--r--tools/perf/util/dwarf-aux.h3
2 files changed, 26 insertions, 1 deletions
diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
index 388c9dcba976..fd460aca36e5 100644
--- a/tools/perf/util/dwarf-aux.c
+++ b/tools/perf/util/dwarf-aux.c
@@ -294,6 +294,28 @@ bool die_is_func_def(Dwarf_Die *dw_die)
}
/**
+ * die_entrypc - Returns entry PC (the lowest address) of a DIE
+ * @dw_die: a DIE
+ * @addr: where to store entry PC
+ *
+ * Since dwarf_entrypc() does not return entry PC if the DIE has only address
+ * range, we have to use this to retrieve the lowest address from the address
+ * range attribute.
+ */
+int die_entrypc(Dwarf_Die *dw_die, Dwarf_Addr *addr)
+{
+ Dwarf_Addr base, end;
+
+ if (!addr)
+ return -EINVAL;
+
+ if (dwarf_entrypc(dw_die, addr) == 0)
+ return 0;
+
+ return dwarf_ranges(dw_die, 0, &base, addr, &end) < 0 ? -ENOENT : 0;
+}
+
+/**
* die_is_func_instance - Ensure that this DIE is an instance of a subprogram
* @dw_die: a DIE
*
@@ -706,7 +728,7 @@ static int __die_walk_funclines(Dwarf_Die *sp_die, bool recursive,
/* Handle function declaration line */
fname = dwarf_decl_file(sp_die);
if (fname && dwarf_decl_line(sp_die, &lineno) == 0 &&
- dwarf_entrypc(sp_die, &addr) == 0) {
+ die_entrypc(sp_die, &addr) == 0) {
lw.retval = callback(fname, lineno, addr, data);
if (lw.retval != 0)
goto done;
diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h
index c42ec366f2a7..598629333eec 100644
--- a/tools/perf/util/dwarf-aux.h
+++ b/tools/perf/util/dwarf-aux.h
@@ -38,6 +38,9 @@ extern int cu_find_lineinfo(Dwarf_Die *cudie, unsigned long addr,
extern int cu_walk_functions_at(Dwarf_Die *cu_die, Dwarf_Addr addr,
int (*callback)(Dwarf_Die *, void *), void *data);
+/* 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) */
extern bool die_is_func_def(Dwarf_Die *dw_die);