From f7cada5f7e7f51fa88428f267ef7216b769fd262 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Fri, 21 Feb 2025 22:10:07 -0800 Subject: [PATCH] perf maps: Switch modules tree walk to io_dir__readdir Compared to glibc's opendir/readdir this lowers the max RSS of perf record by 1.8MB on a Debian machine. Acked-by: Namhyung Kim Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250222061015.303622-3-irogers@google.com Signed-off-by: Namhyung Kim --- tools/perf/util/machine.c | 25 ++++++++----------------- 1 file changed, 8 insertions(+), 17 deletions(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 316f0879e5e0..e394c630e3a2 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -37,6 +37,7 @@ #include // page_size #include "cgroup.h" #include "arm64-frame-pointer-unwind-support.h" +#include #include #include @@ -1339,31 +1340,21 @@ static int maps__set_module_path(struct maps *maps, const char *path, struct kmo static int maps__set_modules_path_dir(struct maps *maps, const char *dir_name, int depth) { - const struct dirent *dent; - DIR *dir = opendir(dir_name); + struct io_dirent64 *dent; + struct io_dir iod; int ret = 0; - if (!dir) { + io_dir__init(&iod, open(dir_name, O_CLOEXEC | O_DIRECTORY | O_RDONLY)); + if (iod.dirfd < 0) { pr_debug("%s: cannot open %s dir\n", __func__, dir_name); return -1; } - while ((dent = readdir(dir)) != NULL) { + while ((dent = io_dir__readdir(&iod)) != NULL) { char path[PATH_MAX]; - unsigned char d_type = dent->d_type; path__join(path, sizeof(path), dir_name, dent->d_name); - - if (d_type == DT_UNKNOWN) { - struct stat st; - - if (stat(path, &st)) - continue; - if (S_ISDIR(st.st_mode)) - d_type = DT_DIR; - } - - if (d_type == DT_DIR) { + if (io_dir__is_dir(&iod, dent)) { if (!strcmp(dent->d_name, ".") || !strcmp(dent->d_name, "..")) continue; @@ -1396,7 +1387,7 @@ static int maps__set_modules_path_dir(struct maps *maps, const char *dir_name, i } out: - closedir(dir); + close(iod.dirfd); return ret; } -- 2.50.1