perf probe: Find compilation directory path for lazy matching

If we use lazy matching, it failed to open a souce file if perf command
is invoked outside of compilation directory:

$ perf probe -a '__schedule;clear_*'
Failed to open kernel/sched/core.c: No such file or directory
  Error: Failed to add events. (-2)

OTOH, other commands like "probe -L" can solve the souce directory by
themselves. Let's make it possible for lazy matching too!

Signed-off-by: Naohiro Aota <naota@elisp.net>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1426223923-1493-1-git-send-email-naota@elisp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Naohiro Aota 2015-03-13 14:18:40 +09:00 committed by Arnaldo Carvalho de Melo
parent 9d7b45c572
commit 09ed8975c4
3 changed files with 74 additions and 60 deletions

View file

@ -655,65 +655,6 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
return ntevs;
}
/*
* Find a src file from a DWARF tag path. Prepend optional source path prefix
* and chop off leading directories that do not exist. Result is passed back as
* a newly allocated path on success.
* Return 0 if file was found and readable, -errno otherwise.
*/
static int get_real_path(const char *raw_path, const char *comp_dir,
char **new_path)
{
const char *prefix = symbol_conf.source_prefix;
if (!prefix) {
if (raw_path[0] != '/' && comp_dir)
/* If not an absolute path, try to use comp_dir */
prefix = comp_dir;
else {
if (access(raw_path, R_OK) == 0) {
*new_path = strdup(raw_path);
return *new_path ? 0 : -ENOMEM;
} else
return -errno;
}
}
*new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
if (!*new_path)
return -ENOMEM;
for (;;) {
sprintf(*new_path, "%s/%s", prefix, raw_path);
if (access(*new_path, R_OK) == 0)
return 0;
if (!symbol_conf.source_prefix) {
/* In case of searching comp_dir, don't retry */
zfree(new_path);
return -errno;
}
switch (errno) {
case ENAMETOOLONG:
case ENOENT:
case EROFS:
case EFAULT:
raw_path = strchr(++raw_path, '/');
if (!raw_path) {
zfree(new_path);
return -ENOENT;
}
continue;
default:
zfree(new_path);
return -errno;
}
}
}
#define LINEBUF_SIZE 256
#define NR_ADDITIONAL_LINES 2

View file

@ -855,11 +855,22 @@ static int probe_point_lazy_walker(const char *fname, int lineno,
static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
{
int ret = 0;
char *fpath;
if (intlist__empty(pf->lcache)) {
const char *comp_dir;
comp_dir = cu_get_comp_dir(&pf->cu_die);
ret = get_real_path(pf->fname, comp_dir, &fpath);
if (ret < 0) {
pr_warning("Failed to find source file path.\n");
return ret;
}
/* Matching lazy line pattern */
ret = find_lazy_match_lines(pf->lcache, pf->fname,
ret = find_lazy_match_lines(pf->lcache, fpath,
pf->pev->point.lazy_line);
free(fpath);
if (ret <= 0)
return ret;
}
@ -1622,3 +1633,61 @@ int debuginfo__find_line_range(struct debuginfo *dbg, struct line_range *lr)
return (ret < 0) ? ret : lf.found;
}
/*
* Find a src file from a DWARF tag path. Prepend optional source path prefix
* and chop off leading directories that do not exist. Result is passed back as
* a newly allocated path on success.
* Return 0 if file was found and readable, -errno otherwise.
*/
int get_real_path(const char *raw_path, const char *comp_dir,
char **new_path)
{
const char *prefix = symbol_conf.source_prefix;
if (!prefix) {
if (raw_path[0] != '/' && comp_dir)
/* If not an absolute path, try to use comp_dir */
prefix = comp_dir;
else {
if (access(raw_path, R_OK) == 0) {
*new_path = strdup(raw_path);
return *new_path ? 0 : -ENOMEM;
} else
return -errno;
}
}
*new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
if (!*new_path)
return -ENOMEM;
for (;;) {
sprintf(*new_path, "%s/%s", prefix, raw_path);
if (access(*new_path, R_OK) == 0)
return 0;
if (!symbol_conf.source_prefix) {
/* In case of searching comp_dir, don't retry */
zfree(new_path);
return -errno;
}
switch (errno) {
case ENAMETOOLONG:
case ENOENT:
case EROFS:
case EFAULT:
raw_path = strchr(++raw_path, '/');
if (!raw_path) {
zfree(new_path);
return -ENOENT;
}
continue;
default:
zfree(new_path);
return -errno;
}
}
}

View file

@ -55,6 +55,10 @@ extern int debuginfo__find_available_vars_at(struct debuginfo *dbg,
struct variable_list **vls,
int max_points, bool externs);
/* Find a src file from a DWARF tag path */
int get_real_path(const char *raw_path, const char *comp_dir,
char **new_path);
struct probe_finder {
struct perf_probe_event *pev; /* Target probe event */