[PATCH 1/1] perf srcline: Optimize comparision against SRCLINE_UNKNOWN

From: Arnaldo Carvalho de Melo
Date: Mon Jun 12 2023 - 10:10:46 EST


This is a string constant that gets returned and then strcmp() around,
we can instead just do a pointer comparision.

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lore.kernel.org/lkml/
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-diff.c | 4 ++--
tools/perf/util/block-info.c | 4 ++--
tools/perf/util/hist.c | 2 +-
tools/perf/util/map.c | 2 +-
tools/perf/util/sort.c | 2 +-
tools/perf/util/srcline.c | 2 +-
6 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/tools/perf/builtin-diff.c b/tools/perf/builtin-diff.c
index eec89567ae483604..e8a1b16aa5f83f4f 100644
--- a/tools/perf/builtin-diff.c
+++ b/tools/perf/builtin-diff.c
@@ -1378,8 +1378,8 @@ static int cycles_printf(struct hist_entry *he, struct hist_entry *pair,
end_line = map__srcline(he->ms.map, bi->sym->start + bi->end,
he->ms.sym);

- if ((strncmp(start_line, SRCLINE_UNKNOWN, strlen(SRCLINE_UNKNOWN)) != 0) &&
- (strncmp(end_line, SRCLINE_UNKNOWN, strlen(SRCLINE_UNKNOWN)) != 0)) {
+ if (start_line != SRCLINE_UNKNOWN &&
+ end_line != SRCLINE_UNKNOWN) {
scnprintf(buf, sizeof(buf), "[%s -> %s] %4ld",
start_line, end_line, block_he->diff.cycles);
} else {
diff --git a/tools/perf/util/block-info.c b/tools/perf/util/block-info.c
index 08279b1b65e5a4b0..fe4c17248799f0a2 100644
--- a/tools/perf/util/block-info.c
+++ b/tools/perf/util/block-info.c
@@ -296,8 +296,8 @@ static int block_range_entry(struct perf_hpp_fmt *fmt, struct perf_hpp *hpp,
end_line = map__srcline(he->ms.map, bi->sym->start + bi->end,
he->ms.sym);

- if ((strncmp(start_line, SRCLINE_UNKNOWN, strlen(SRCLINE_UNKNOWN)) != 0) &&
- (strncmp(end_line, SRCLINE_UNKNOWN, strlen(SRCLINE_UNKNOWN)) != 0)) {
+ if (start_line != SRCLINE_UNKNOWN) &&
+ end_line != SRCLINE_UNKNOWN) {
scnprintf(buf, sizeof(buf), "[%s -> %s]",
start_line, end_line);
} else {
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index 0a10bcc6ec95b5e0..3dc8a4968beb9c01 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -484,7 +484,7 @@ static int hist_entry__init(struct hist_entry *he,
goto err_infos;
}

- if (he->srcline && strcmp(he->srcline, SRCLINE_UNKNOWN)) {
+ if (he->srcline && he->srcline != SRCLINE_UNKNOWN) {
he->srcline = strdup(he->srcline);
if (he->srcline == NULL)
goto err_rawdata;
diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index c77e2fce6a379e7f..f30d34903aa4eabe 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -496,7 +496,7 @@ int map__fprintf_srcline(struct map *map, u64 addr, const char *prefix,

if (dso) {
char *srcline = map__srcline(map, addr, NULL);
- if (strncmp(srcline, SRCLINE_UNKNOWN, strlen(SRCLINE_UNKNOWN)) != 0)
+ if (srcline != SRCLINE_UNKNOWN)
ret = fprintf(fp, "%s%s", prefix, srcline);
zfree_srcline(&srcline);
}
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 047c3606802f5b7f..6aa1c7f2b4448b30 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -643,7 +643,7 @@ static char *hist_entry__get_srcfile(struct hist_entry *e)

sf = __get_srcline(map__dso(map), map__rip_2objdump(map, e->ip),
e->ms.sym, false, true, true, e->ip);
- if (!strcmp(sf, SRCLINE_UNKNOWN))
+ if (sf == SRCLINE_UNKNOWN)
return no_srcfile;
p = strchr(sf, ':');
if (p && *sf) {
diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
index b8e596528d7e7e5e..48a04f42b308b080 100644
--- a/tools/perf/util/srcline.c
+++ b/tools/perf/util/srcline.c
@@ -809,7 +809,7 @@ void zfree_srcline(char **srcline)
if (*srcline == NULL)
return;

- if (strcmp(*srcline, SRCLINE_UNKNOWN))
+ if (*srcline != SRCLINE_UNKNOWN)
free(*srcline);

*srcline = NULL;
--
2.39.2


> Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> ---
> tools/perf/util/hist.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
> index 77cb2cc83bb9..cc6f7f51faa5 100644
> --- a/tools/perf/util/hist.c
> +++ b/tools/perf/util/hist.c
> @@ -484,7 +484,7 @@ static int hist_entry__init(struct hist_entry *he,
> goto err_infos;
> }
>
> - if (he->srcline) {
> + if (he->srcline && strcmp(he->srcline, SRCLINE_UNKNOWN)) {
> he->srcline = strdup(he->srcline);
> if (he->srcline == NULL)
> goto err_rawdata;
> --
> 2.41.0.162.gfafddb0af9-goog
>

--

- Arnaldo