Re: [PATCH v2] perf probe: Find compilation directory path for lazy matching
From: Masami Hiramatsu
Date: Wed Mar 04 2015 - 07:34:49 EST
(2015/03/04 16:52), Naohiro Aota wrote:
> 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!
>
Looks good to me :)
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Thank you!
> 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 1c570c2..adb8d1f 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -515,65 +515,6 @@ 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..e6c0262 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.
> + */
> +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;
> + }
> + }
> +}
> diff --git a/tools/perf/util/probe-finder.h b/tools/perf/util/probe-finder.h
> index 92590b2..5ef82dd 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 */
> +extern 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 */
>
>
--
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Research Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@xxxxxxxxxxx
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