}
/*
- * get_init_cgroup: get the cgroup init is in.
- * @subsystem: the exact cgroup subsystem to look up (I.e. "freezer")
- * @mntent: a mntent (from getmntent) whose mntopts contains the subsystem to
- * look up.
- * @dsg: preallocated buffer of at least size MAXPATHLEN in which the path will
- * be copied.
- * @prependslash: if 1, the path will have a '/' prepended for easy of use by
- * the caller.
- *
- * subsystem and mntent can both be NULL, in which case we return
- * the first entry in /proc/1/cgroup.
- *
- * Returns a pointer to the answer (which is just the passed-in @dsg), which
- * may be "".
- */
-static char *get_init_cgroup(const char *subsystem, struct mntent *mntent,
- char *dsg, int prependslash)
-{
- FILE *f;
- char *c, *c2;
- char line[MAXPATHLEN];
- int ret;
-
- *dsg = '\0';
- f = fopen("/proc/1/cgroup", "r");
- if (!f)
- return dsg;
-
- while (fgets(line, MAXPATHLEN, f)) {
- c = index(line, ':');
- if (!c)
- continue;
- c++;
- c2 = index(c, ':');
- if (!c2)
- continue;
- *c2 = '\0';
- c2++;
- if (!subsystem && !mntent)
- goto good;
- if (subsystem && strcmp(c, subsystem) != 0)
- continue;
- if (mntent && !hasmntopt(mntent, c))
- continue;
-good:
- DEBUG("get_init_cgroup: found init cgroup for subsys %s at %s\n",
- subsystem, c2);
- ret = snprintf(dsg, MAXPATHLEN, "%s%s", prependslash ? "/" : "", c2);
- if (ret < 0 || ret >= MAXPATHLEN) {
- WARN("init cgroup path name was too long.");
- goto found;
- }
- if (ret < 1)
- goto found;
-
- c = &dsg[ret-1];
- if (*c == '\n')
- *c = '\0';
-
- goto found;
- }
-
-found:
- fclose(f);
- return dsg;
-}
-
-/*
- * Determine mountpoint for a cgroup subsystem, plus the cgroup path in that
- * subsytem of the container init.
+ * Determine mountpoint for a cgroup subsystem.
* @subsystem: cgroup subsystem (i.e. freezer). If this is NULL, the first
* cgroup mountpoint with any subsystems is used.
* @mnt: a passed-in buffer of at least size MAXPATHLEN into which the path
static int get_cgroup_mount(const char *subsystem, char *mnt)
{
struct mntent *mntent;
- char initcgroup[MAXPATHLEN], *init;
FILE *file = NULL;
int ret, err = -1;
continue;
}
- init = get_init_cgroup(NULL, mntent, initcgroup, 1);
- ret = snprintf(mnt, MAXPATHLEN, "%s%s", mntent->mnt_dir,
- init);
+ ret = snprintf(mnt, MAXPATHLEN, "%s", mntent->mnt_dir);
if (ret < 0 || ret >= MAXPATHLEN)
goto fail;
return count;
}
-/*
- * Set of helper functions to make sure that, when we create a new
- * cpuset cgroup, its cpus and mems files inherit the values in the
- * parent cgroup
- */
-static long get_value(const char *dir, const char *file)
-{
- FILE *f;
- char path[MAXPATHLEN];
- int ret, retv;
-
- retv = snprintf(path, MAXPATHLEN, "%s/%s", dir, file);
- if (retv < 0 || retv >= MAXPATHLEN)
- return 0;
- f = fopen(path, "r");
- ret = fscanf(f, "%d", &retv);
- fclose(f);
- if (ret != 1)
- return 0;
- return retv;
-}
-
-static void set_value(const char *dir, const char *file, long v)
-{
- FILE *f;
- char path[MAXPATHLEN];
- int retv;
-
- retv = snprintf(path, MAXPATHLEN, "%s/%s", dir, file);
- if (retv < 0 || retv >= MAXPATHLEN)
- return;
- f = fopen(path, "w");
- fprintf(f, "%ld\n", v);
- fclose(f);
-}
-
-static void setup_cpuset(const char *path)
-{
- /* copy parent values for mems_allowed and cpus_allowed */
- char *parentpath = strdup(path);
- char *p;
- long v;
- if ((p = rindex(parentpath, '/')) == NULL)
- goto out;
- v = get_value(parentpath, "cpuset.mems");
- set_value(path, "cpuset.mems", v);
- v = get_value(parentpath, "cpuset.cpus");
- set_value(path, "cpuset.cpus", v);
-
-out:
- free(parentpath);
-}
-
/*
* If first creating the /sys/fs/cgroup/$subsys/lxc container, then
* try to set clone_children to 1. Some kernels don't support
* hooks/mountcgroup) check if cpuset is in the subsystems, and if so
* manually copy over mems and cpus.
*/
-static void set_clone_children(const char *mntdir, const char *init)
+static void set_clone_children(const char *mntdir)
{
char path[MAXPATHLEN];
FILE *fout;
int ret;
- ret = snprintf(path, MAXPATHLEN, "%s%s/cgroup.clone_children", mntdir, init);
+ ret = snprintf(path, MAXPATHLEN, "%s/cgroup.clone_children", mntdir);
INFO("writing to %s\n", path);
if (ret < 0 || ret > MAXPATHLEN)
return;
FILE *file = NULL;
struct mntent *mntent;
int ret, retv = -1;
- char path[MAXPATHLEN], initpath[MAXPATHLEN];
+ char path[MAXPATHLEN];
file = setmntent(MTAB, "r");
if (!file) {
}
while ((mntent = getmntent(file))) {
- char *init = get_init_cgroup(NULL, mntent, initpath, 1);
if (strcmp(mntent->mnt_type, "cgroup"))
continue;
/*
* TODO - handle case where lxcgroup has subdirs? (i.e. build/l1)
- * May not be worthwhile - remember cgroup depth has perf penalties
- * */
- ret = snprintf(path, MAXPATHLEN, "%s%s/%s",
- mntent->mnt_dir, init, lxcgroup ? lxcgroup : "lxc");
+ * We probably only want to support that for /users/joe
+ */
+ ret = snprintf(path, MAXPATHLEN, "%s/%s",
+ mntent->mnt_dir, lxcgroup ? lxcgroup : "lxc");
if (ret < 0 || ret >= MAXPATHLEN)
goto fail;
if (access(path, F_OK)) {
- set_clone_children(mntent->mnt_dir, init);
+ set_clone_children(mntent->mnt_dir);
ret = mkdir(path, 0755);
if (ret == -1 && errno != EEXIST) {
SYSERROR("failed to create '%s' directory", path);
goto fail;
}
- } else if (hasmntopt(mntent, "cpuset")) {
- setup_cpuset(path);
}
}
* free that eventually, however the lxc monitor will keep that string so as to
* return it in response to a LXC_COMMAND_CGROUP query.
*
- * Note the path is relative to cgroup mounts plus the caller's init task's
- * cgroup. I.e. if init is in cgroup /init and the freezer subsystem is at
- * /sys/fs/cgroup/freezer, and this fn returns '/lxc/r1', then the freezer
- * cgroup's full path will be /sys/fs/cgroup/freezer/init/lxc/r1/. Note also
- * that this should cleanly account for init being in different cgroups for
- * different subsystems.
+ * Note the path is relative to cgroup mounts. I.e. if the freezer subsystem
+ * is at /sys/fs/cgroup/freezer, and this fn returns '/lxc/r1', then the
+ * freezer cgroup's full path will be /sys/fs/cgroup/freezer/lxc/r1/.
*
* XXX This should probably be locked globally
*
char *lxc_cgroup_path_create(const char *lxcgroup, const char *name)
{
int i = 0, ret;
- char *retpath, path[MAXPATHLEN], initpath[MAXPATHLEN], *init;
+ char *retpath, path[MAXPATHLEN];
char tail[12];
FILE *file = NULL;
struct mntent *mntent;
if (!mount_has_subsystem(mntent))
continue;
- init = get_init_cgroup(NULL, mntent, initpath, 1);
- /* find unused mnt_dir + init_cgroup + lxcgroup + name + -$i */
- ret = snprintf(path, MAXPATHLEN, "%s%s/%s/%s%s",
- mntent->mnt_dir, init,
+ /* find unused mnt_dir + lxcgroup + name + -$i */
+ ret = snprintf(path, MAXPATHLEN, "%s/%s/%s%s", mntent->mnt_dir,
lxcgroup ? lxcgroup : "lxc", name, tail);
if (ret < 0 || ret >= MAXPATHLEN)
goto fail;
goto fail;
}
- if (hasmntopt(mntent, "cpuset")) {
- setup_cpuset(path);
- }
}
endmntent(file);
int lxc_cgroup_enter(const char *cgpath, pid_t pid)
{
- char path[MAXPATHLEN], initpath[MAXPATHLEN], *init;
+ char path[MAXPATHLEN];
FILE *file = NULL, *fout;
struct mntent *mntent;
int ret, retv = -1;
continue;
if (!mount_has_subsystem(mntent))
continue;
- init = get_init_cgroup(NULL, mntent, initpath, 1);
- ret = snprintf(path, MAXPATHLEN, "%s%s/%s/tasks",
- mntent->mnt_dir, init, cgpath);
+ ret = snprintf(path, MAXPATHLEN, "%s/%s/tasks",
+ mntent->mnt_dir, cgpath);
if (ret < 0 || ret >= MAXPATHLEN) {
ERROR("entering cgroup");
goto out;
static int lxc_one_cgroup_destroy(struct mntent *mntent, const char *cgpath)
{
- char cgname[MAXPATHLEN], initcgroup[MAXPATHLEN];
+ char cgname[MAXPATHLEN];
char *cgmnt = mntent->mnt_dir;
int rc;
- rc = snprintf(cgname, MAXPATHLEN, "%s%s/%s", cgmnt,
- get_init_cgroup(NULL, mntent, initcgroup, 1), cgpath);
+ rc = snprintf(cgname, MAXPATHLEN, "%s/%s", cgmnt, cgpath);
if (rc < 0 || rc >= MAXPATHLEN) {
ERROR("name too long");
return -1;
projects / mirror_lxc.git / blobdiff