From: Masami Hiramatsu mhiramat@kernel.org
[ Upstream commit 86c0bf8539e7f46d91bd105e55eda96e0064caef ]
Fix to show calling lines of inlined functions (where an inline function is called).
die_walk_lines() filtered out the lines inside inlined functions based on the address. However this also filtered out the lines which call those inlined functions from the target function.
To solve this issue, check the call_file and call_line attributes and do not filter out if it matches to the line information.
Without this fix, perf probe -L doesn't show some lines correctly. (don't see the lines after 17)
# perf probe -L vfs_read <vfs_read@/home/mhiramat/ksrc/linux/fs/read_write.c:0> 0 ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) 1 { 2 ssize_t ret;
4 if (!(file->f_mode & FMODE_READ)) return -EBADF; 6 if (!(file->f_mode & FMODE_CAN_READ)) return -EINVAL; 8 if (unlikely(!access_ok(buf, count))) return -EFAULT;
11 ret = rw_verify_area(READ, file, pos, count); 12 if (!ret) { 13 if (count > MAX_RW_COUNT) count = MAX_RW_COUNT; 15 ret = __vfs_read(file, buf, count, pos); 16 if (ret > 0) { fsnotify_access(file); add_rchar(current, ret); }
With this fix:
# perf probe -L vfs_read <vfs_read@/home/mhiramat/ksrc/linux/fs/read_write.c:0> 0 ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) 1 { 2 ssize_t ret;
4 if (!(file->f_mode & FMODE_READ)) return -EBADF; 6 if (!(file->f_mode & FMODE_CAN_READ)) return -EINVAL; 8 if (unlikely(!access_ok(buf, count))) return -EFAULT;
11 ret = rw_verify_area(READ, file, pos, count); 12 if (!ret) { 13 if (count > MAX_RW_COUNT) count = MAX_RW_COUNT; 15 ret = __vfs_read(file, buf, count, pos); 16 if (ret > 0) { 17 fsnotify_access(file); 18 add_rchar(current, ret); } 20 inc_syscr(current); }
Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface") Signed-off-by: Masami Hiramatsu mhiramat@kernel.org Tested-by: Arnaldo Carvalho de Melo acme@redhat.com Cc: Jiri Olsa jolsa@redhat.com Cc: Namhyung Kim namhyung@kernel.org Link: http://lore.kernel.org/lkml/157241937995.32002.17899884017011512577.stgit@de... Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/util/dwarf-aux.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c index 3aea343c71798..41bfb4c977d03 100644 --- a/tools/perf/util/dwarf-aux.c +++ b/tools/perf/util/dwarf-aux.c @@ -765,7 +765,7 @@ int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, void *data) Dwarf_Lines *lines; Dwarf_Line *line; Dwarf_Addr addr; - const char *fname, *decf = NULL; + const char *fname, *decf = NULL, *inf = NULL; int lineno, ret = 0; int decl = 0, inl; Dwarf_Die die_mem, *cu_die; @@ -809,13 +809,21 @@ int die_walk_lines(Dwarf_Die *rt_die, line_walk_callback_t callback, void *data) */ if (!dwarf_haspc(rt_die, addr)) continue; + if (die_find_inlinefunc(rt_die, addr, &die_mem)) { + /* Call-site check */ + inf = die_get_call_file(&die_mem); + if ((inf && !strcmp(inf, decf)) && + die_get_call_lineno(&die_mem) == lineno) + goto found; + dwarf_decl_line(&die_mem, &inl); if (inl != decl || decf != dwarf_decl_file(&die_mem)) continue; } } +found: /* Get source line */ fname = dwarf_linesrc(line, NULL, NULL);