Re: [PATCH v3] perf probe: Find compilation directory path for lazy matching
From: Masami Hiramatsu
Date: Tue Apr 14 2015 - 02:35:51 EST
(2015/04/14 8:10), Arnaldo Carvalho de Melo wrote:
> Em Fri, Mar 13, 2015 at 02:18:40PM +0900, Naohiro Aota escreveu:
>> 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)
>
> Masami, you mean this one, right?
Yes, this is what I meant :)
Thank you!
>
> - Arnaldo
>
>> 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@xxxxxxxxx>
>> ---
>> tools/perf/util/probe-event.c | 59 -----------------------------------
>> tools/perf/util/probe-finder.c | 71 +++++++++++++++++++++++++++++++++++++++++-
>> tools/perf/util/probe-finder.h | 4 +++
>> 3 files changed, 74 insertions(+), 60 deletions(-)
>>
>> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
>> index f272a71..32a429b 100644
>> --- a/tools/perf/util/probe-event.c
>> +++ b/tools/perf/util/probe-event.c
>> @@ -648,65 +648,6 @@ 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
>>
>> diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
>> index 46f009a..0fd2df4 100644
>> --- a/tools/perf/util/probe-finder.c
>> +++ b/tools/perf/util/probe-finder.c
>> @@ -849,11 +849,22 @@ 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;
>> }
>> @@ -1616,3 +1627,61 @@ found:
>> 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;
>> + }
>> + }
>> +}
>> diff --git a/tools/perf/util/probe-finder.h b/tools/perf/util/probe-finder.h
>> index 92590b2..ebf8c8c 100644
>> --- a/tools/perf/util/probe-finder.h
>> +++ b/tools/perf/util/probe-finder.h
>> @@ -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 */
>>
>> --
>> 2.3.1
>
--
Masami HIRAMATSU
Linux Technology Research Center, System Productivity Research Dept.
Center for Technology Innovation - Systems Engineering
Hitachi, Ltd., Research & Development Group
E-mail: masami.hiramatsu.pt@xxxxxxxxxxx
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