int cg_is_empty(const char *controller, const char *path, bool ignore_self) {
pid_t pid = 0;
int r;
FILE *f = NULL;
bool found = false;
assert(controller);
assert(path);
if ((r = cg_enumerate_tasks(controller, path, &f)) < 0)
return r == -ENOENT ? 1 : r;
while ((r = cg_read_pid(f, &pid)) > 0) {
if (ignore_self && pid == getpid())
continue;
found = true;
break;
}
fclose(f);
if (r < 0)
return r;
return !found;
}
int cg_migrate(const char *cfrom, const char *pfrom, const char *cto, const char *pto, bool ignore_self) {
bool done = false;
_cleanup_set_free_ Set *s = NULL;
int r, ret = 0;
pid_t my_pid;
_cleanup_fclose_ FILE *f = NULL;
assert(cfrom);
assert(pfrom);
assert(cto);
assert(pto);
s = set_new(trivial_hash_func, trivial_compare_func);
if (!s)
return -ENOMEM;
my_pid = getpid();
do {
pid_t pid = 0;
done = true;
r = cg_enumerate_tasks(cfrom, pfrom, &f);
if (r < 0) {
if (ret >= 0 && r != -ENOENT)
ret = r;
return ret;
}
while ((r = cg_read_pid(f, &pid)) > 0) {
/* This might do weird stuff if we aren't a
* single-threaded program. However, we
* luckily know we are not */
if (pid == my_pid && ignore_self)
continue;
if (set_get(s, LONG_TO_PTR(pid)) == LONG_TO_PTR(pid))
continue;
r = cg_attach(cto, pto, pid);
if (r < 0) {
if (ret >= 0 && r != -ESRCH)
ret = r;
} else if (ret == 0)
ret = 1;
done = false;
r = set_put(s, LONG_TO_PTR(pid));
if (r < 0) {
if (ret >= 0)
ret = r;
return ret;
}
}
if (r < 0) {
if (ret >= 0)
ret = r;
return ret;
}
fclose(f);
f = NULL;
} while (!done);
return ret;
}
int cg_migrate(const char *controller, const char *from, const char *to, bool ignore_self) {
bool done = false;
Set *s;
int r, ret = 0;
pid_t my_pid;
FILE *f = NULL;
assert(controller);
assert(from);
assert(to);
if (!(s = set_new(trivial_hash_func, trivial_compare_func)))
return -ENOMEM;
my_pid = getpid();
do {
pid_t pid = 0;
done = true;
if ((r = cg_enumerate_tasks(controller, from, &f)) < 0) {
if (ret >= 0 && r != -ENOENT)
ret = r;
goto finish;
}
while ((r = cg_read_pid(f, &pid)) > 0) {
/* This might do weird stuff if we aren't a
* single-threaded program. However, we
* luckily know we are not */
if (pid == my_pid && ignore_self)
continue;
if (set_get(s, LONG_TO_PTR(pid)) == LONG_TO_PTR(pid))
continue;
if ((r = cg_attach(controller, to, pid)) < 0) {
if (ret >= 0 && r != -ESRCH)
ret = r;
} else if (ret == 0)
ret = 1;
done = false;
if ((r = set_put(s, LONG_TO_PTR(pid))) < 0) {
if (ret >= 0)
ret = r;
goto finish;
}
}
if (r < 0) {
if (ret >= 0)
ret = r;
goto finish;
}
fclose(f);
f = NULL;
} while (!done);
finish:
set_free(s);
if (f)
fclose(f);
return ret;
}
static int process(const char *controller, const char *path, Hashmap *a, Hashmap *b, unsigned iteration) {
Group *g;
int r;
FILE *f;
pid_t pid;
unsigned n;
assert(controller);
assert(path);
assert(a);
g = hashmap_get(a, path);
if (!g) {
g = hashmap_get(b, path);
if (!g) {
g = new0(Group, 1);
if (!g)
return -ENOMEM;
g->path = strdup(path);
if (!g->path) {
group_free(g);
return -ENOMEM;
}
r = hashmap_put(a, g->path, g);
if (r < 0) {
group_free(g);
return r;
}
} else {
assert_se(hashmap_move_one(a, b, path) == 0);
g->cpu_valid = g->memory_valid = g->io_valid = g->n_tasks_valid = false;
}
}
/* Regardless which controller, let's find the maximum number
* of processes in any of it */
r = cg_enumerate_tasks(controller, path, &f);
if (r < 0)
return r;
n = 0;
while (cg_read_pid(f, &pid) > 0)
n++;
fclose(f);
if (n > 0) {
if (g->n_tasks_valid)
g->n_tasks = MAX(g->n_tasks, n);
else
g->n_tasks = n;
g->n_tasks_valid = true;
}
if (streq(controller, "cpuacct")) {
uint64_t new_usage;
char *p, *v;
struct timespec ts;
r = cg_get_path(controller, path, "cpuacct.usage", &p);
if (r < 0)
return r;
r = read_one_line_file(p, &v);
free(p);
if (r < 0)
return r;
r = safe_atou64(v, &new_usage);
free(v);
if (r < 0)
return r;
assert_se(clock_gettime(CLOCK_MONOTONIC, &ts) == 0);
if (g->cpu_iteration == iteration - 1) {
uint64_t x, y;
x = ((uint64_t) ts.tv_sec * 1000000000ULL + (uint64_t) ts.tv_nsec) -
((uint64_t) g->cpu_timestamp.tv_sec * 1000000000ULL + (uint64_t) g->cpu_timestamp.tv_nsec);
y = new_usage - g->cpu_usage;
if (y > 0) {
g->cpu_fraction = (double) y / (double) x;
g->cpu_valid = true;
}
}
g->cpu_usage = new_usage;
g->cpu_timestamp = ts;
g->cpu_iteration = iteration;
} else if (streq(controller, "memory")) {
char *p, *v;
r = cg_get_path(controller, path, "memory.usage_in_bytes", &p);
if (r < 0)
return r;
r = read_one_line_file(p, &v);
free(p);
if (r < 0)
return r;
r = safe_atou64(v, &g->memory);
free(v);
if (r < 0)
return r;
if (g->memory > 0)
g->memory_valid = true;
} else if (streq(controller, "blkio")) {
char *p;
uint64_t wr = 0, rd = 0;
struct timespec ts;
r = cg_get_path(controller, path, "blkio.io_service_bytes", &p);
if (r < 0)
return r;
f = fopen(p, "re");
free(p);
if (!f)
return -errno;
for (;;) {
char line[LINE_MAX], *l;
uint64_t k, *q;
if (!fgets(line, sizeof(line), f))
break;
l = strstrip(line);
l += strcspn(l, WHITESPACE);
l += strspn(l, WHITESPACE);
if (first_word(l, "Read")) {
l += 4;
q = &rd;
} else if (first_word(l, "Write")) {
l += 5;
q = ≀
} else
continue;
l += strspn(l, WHITESPACE);
r = safe_atou64(l, &k);
if (r < 0)
continue;
*q += k;
}
fclose(f);
assert_se(clock_gettime(CLOCK_MONOTONIC, &ts) == 0);
if (g->io_iteration == iteration - 1) {
uint64_t x, yr, yw;
x = ((uint64_t) ts.tv_sec * 1000000000ULL + (uint64_t) ts.tv_nsec) -
((uint64_t) g->io_timestamp.tv_sec * 1000000000ULL + (uint64_t) g->io_timestamp.tv_nsec);
yr = rd - g->io_input;
yw = wr - g->io_output;
if (yr > 0 || yw > 0) {
g->io_input_bps = (yr * 1000000000ULL) / x;
g->io_output_bps = (yw * 1000000000ULL) / x;
g->io_valid = true;
}
}
g->io_input = rd;
g->io_output = wr;
g->io_timestamp = ts;
g->io_iteration = iteration;
}
return 0;
}