/**
* Tests the cgroup_attach_cgroup() api under different scenarios
* @param retcode error code in case any error is expected from api
* @param cgrp the group to assign the task to
* @param group1 the name of the group under first (single) mountpoint
* @param group2 the name of the group under 2nd moutpoint for multimount
* @param i the test number
* @param k the message enum number to print the useful message
*/
void test_cgroup_attach_task(int retcode, struct cgroup *cgrp,
const char *group1, const char *group2, pid_t pid, int k, int i)
{
int retval;
char tasksfile[FILENAME_MAX], tasksfile2[FILENAME_MAX];
/* Check, In case some error is expected due to a negative scenario */
if (retcode) {
if (pid)
retval = cgroup_attach_task_pid(cgrp, pid);
else
retval = cgroup_attach_task(cgrp);
if (retval == retcode)
message(i, PASS, "attach_task()", retval, info[k]);
else
message(i, FAIL, "attach_task()", retval, info[k]);
return;
}
/* Now there is no error and it is a genuine call */
if (pid)
retval = cgroup_attach_task_pid(cgrp, pid);
else
retval = cgroup_attach_task(cgrp);
/* API returned success, so perform check */
if (retval == 0) {
build_path(tasksfile, mountpoint,
group1, "tasks");
if (check_task(tasksfile, 0)) {
if (fs_mounted == 2) {
/* multiple mounts */
build_path(tasksfile2, mountpoint2,
group2, "tasks");
if (check_task(tasksfile2, 0)) {
message(i, PASS, "attach_task()",
retval, info[TASKINGRP]);
} else {
message(i, FAIL, "attach_task()",
retval, info[TASKNOTINANYGRP]);
}
} else {
/* single mount */
message(i, PASS, "attach_task()",
retval, info[TASKINGRP]);
}
} else {
message(i, FAIL, "attach_task()", retval,
info[TASKNOTINGRP]);
}
} else {
message(i, FAIL, "attach_task()", retval, (char *)"\n");
}
}
static int l_cgroup_attach_task_pid(lua_State *L)
{
struct u_cgroup *uc = check_cgroup(L, 1);
int pid = luaL_checkinteger(L, 2);
lua_pushinteger(L, cgroup_attach_task_pid(uc->group, pid));
return 1;
}
int container_add_task(envid_t veid)
{
char cgrp[CT_MAX_STR_SIZE];
struct cgroup *ct;
int ret;
veid_to_name(cgrp, veid);
ct = cgroup_new_cgroup(cgrp);
ret = cgroup_get_cgroup(ct);
if (ret)
goto out;
ret = cgroup_attach_task_pid(ct, getpid());
out:
cgroup_free(&ct);
return ret;
}
static mrb_value mrb_cgroup_attach(mrb_state *mrb, mrb_value self)
{
mrb_cgroup_context *mrb_cg_cxt = mrb_cgroup_get_context(mrb, self, "mrb_cgroup_context");
mrb_value pid = mrb_nil_value();
mrb_get_args(mrb, "|i", &pid);
if (mrb_nil_p(pid)) {
cgroup_attach_task(mrb_cg_cxt->cg);
} else {
cgroup_attach_task_pid(mrb_cg_cxt->cg, mrb_fixnum(pid));
}
mrb_iv_set(mrb
, self
, mrb_intern_cstr(mrb, "mrb_cgroup_context")
, mrb_obj_value(Data_Wrap_Struct(mrb
, mrb->object_class
, &mrb_cgroup_context_type
, (void *)mrb_cg_cxt)
)
);
return self;
}
int
ProcFamily::migrate_to_cgroup(pid_t pid)
{
// Attempt to migrate a given process to a cgroup.
// This can be done without regards to whether the
// process is already in the cgroup
if (!m_cgroup.isValid()) {
return 1;
}
// We want to make sure task migration is turned on for the
// associated memory controller. So, we get to look up the original cgroup.
//
// If there is no memory controller present, we skip all this and just attempt a migrate
int err;
u_int64_t orig_migrate;
bool changed_orig = false;
char * orig_cgroup_string = NULL;
struct cgroup * orig_cgroup;
struct cgroup_controller * memory_controller;
if (m_cm.isMounted(CgroupManager::MEMORY_CONTROLLER) && (err = cgroup_get_current_controller_path(pid, MEMORY_CONTROLLER_STR, &orig_cgroup_string))) {
dprintf(D_PROCFAMILY,
"Unable to determine current memory cgroup for PID %u (ProcFamily %u): %u %s\n",
pid, m_root_pid, err, cgroup_strerror(err));
return 1;
}
// We will migrate the PID to the new cgroup even if it is in the proper memory controller cgroup
// It is possible for the task to be in multiple cgroups.
if (m_cm.isMounted(CgroupManager::MEMORY_CONTROLLER) && (orig_cgroup_string != NULL) && (strcmp(m_cgroup_string.c_str(), orig_cgroup_string))) {
// Yes, there are race conditions here - can't really avoid this.
// Throughout this block, we can assume memory controller exists.
// Get original value of migrate.
orig_cgroup = cgroup_new_cgroup(orig_cgroup_string);
ASSERT (orig_cgroup != NULL);
if ((err = cgroup_get_cgroup(orig_cgroup))) {
dprintf(D_PROCFAMILY,
"Unable to read original cgroup %s (ProcFamily %u): %u %s\n",
orig_cgroup_string, m_root_pid, err, cgroup_strerror(err));
goto after_migrate;
}
if ((memory_controller = cgroup_get_controller(orig_cgroup, MEMORY_CONTROLLER_STR)) == NULL) {
cgroup_free(&orig_cgroup);
goto after_migrate;
}
if ((err = cgroup_get_value_uint64(memory_controller, "memory.move_charge_at_immigrate", &orig_migrate))) {
if (err == ECGROUPVALUENOTEXIST) {
// Older kernels don't have the ability to migrate memory accounting to the new cgroup.
dprintf(D_PROCFAMILY,
"This kernel does not support memory usage migration; cgroup %s memory statistics"
" will be slightly incorrect (ProcFamily %u)\n",
m_cgroup_string.c_str(), m_root_pid);
} else {
dprintf(D_PROCFAMILY,
"Unable to read cgroup %s memory controller settings for "
"migration (ProcFamily %u): %u %s\n",
orig_cgroup_string, m_root_pid, err, cgroup_strerror(err));
}
cgroup_free(&orig_cgroup);
goto after_migrate;
}
if (orig_migrate != 3) {
orig_cgroup = cgroup_new_cgroup(orig_cgroup_string);
memory_controller = cgroup_add_controller(orig_cgroup, MEMORY_CONTROLLER_STR);
ASSERT (memory_controller != NULL); // Memory controller must already exist
cgroup_add_value_uint64(memory_controller, "memory.move_charge_at_immigrate", 3);
if ((err = cgroup_modify_cgroup(orig_cgroup))) {
// Not allowed to change settings
dprintf(D_ALWAYS,
"Unable to change cgroup %s memory controller settings for migration. "
"Some memory accounting will be inaccurate (ProcFamily %u): %u %s\n",
orig_cgroup_string, m_root_pid, err, cgroup_strerror(err));
} else {
changed_orig = true;
}
}
cgroup_free(&orig_cgroup);
}
after_migrate:
orig_cgroup = NULL;
err = cgroup_attach_task_pid(& const_cast<struct cgroup &>(m_cgroup.getCgroup()), pid);
if (err) {
dprintf(D_PROCFAMILY,
"Cannot attach pid %u to cgroup %s for ProcFamily %u: %u %s\n",
pid, m_cgroup_string.c_str(), m_root_pid, err, cgroup_strerror(err));
}
if (changed_orig) {
if ((orig_cgroup = cgroup_new_cgroup(orig_cgroup_string))) {
goto after_restore;
}
if (((memory_controller = cgroup_add_controller(orig_cgroup, MEMORY_CONTROLLER_STR)) != NULL) &&
(!cgroup_add_value_uint64(memory_controller, "memory.move_charge_at_immigrate", orig_migrate))) {
cgroup_modify_cgroup(orig_cgroup);
}
cgroup_free(&orig_cgroup);
}
after_restore:
if (orig_cgroup_string != NULL) {
free(orig_cgroup_string);
}
return err;
}
