[PATCH v2 14/16] tools api fs: Dynamically allocate cgroupfs mount point cache

From: Ian Rogers
Date: Fri May 26 2023 - 14:35:47 EST


Move the cgroupfs_cache_entry 4128 byte array out of .bss.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/lib/api/fs/cgroup.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/tools/lib/api/fs/cgroup.c b/tools/lib/api/fs/cgroup.c
index 1573dae4259d..250629a09423 100644
--- a/tools/lib/api/fs/cgroup.c
+++ b/tools/lib/api/fs/cgroup.c
@@ -14,7 +14,7 @@ struct cgroupfs_cache_entry {
};

/* just cache last used one */
-static struct cgroupfs_cache_entry cached;
+static struct cgroupfs_cache_entry *cached;

int cgroupfs_find_mountpoint(char *buf, size_t maxlen, const char *subsys)
{
@@ -24,9 +24,9 @@ int cgroupfs_find_mountpoint(char *buf, size_t maxlen, const char *subsys)
char *p, *path;
char mountpoint[PATH_MAX];

- if (!strcmp(cached.subsys, subsys)) {
- if (strlen(cached.mountpoint) < maxlen) {
- strcpy(buf, cached.mountpoint);
+ if (cached && !strcmp(cached->subsys, subsys)) {
+ if (strlen(cached->mountpoint) < maxlen) {
+ strcpy(buf, cached->mountpoint);
return 0;
}
return -1;
@@ -91,8 +91,13 @@ int cgroupfs_find_mountpoint(char *buf, size_t maxlen, const char *subsys)
free(line);
fclose(fp);

- strncpy(cached.subsys, subsys, sizeof(cached.subsys) - 1);
- strcpy(cached.mountpoint, mountpoint);
+ if (!cached)
+ cached = calloc(1, sizeof(*cached));
+
+ if (cached) {
+ strncpy(cached->subsys, subsys, sizeof(cached->subsys) - 1);
+ strcpy(cached->mountpoint, mountpoint);
+ }

if (mountpoint[0] && strlen(mountpoint) < maxlen) {
strcpy(buf, mountpoint);
--
2.41.0.rc0.172.g3f132b7071-goog