struct iscsi_conn *iscsi_rx_thread_pre_handler(struct iscsi_thread_set *ts)
{
int ret;
spin_lock_bh(&ts->ts_state_lock);
if (ts->create_threads) {
spin_unlock_bh(&ts->ts_state_lock);
goto sleep;
}
flush_signals(current);
if (ts->delay_inactive && (--ts->thread_count == 0)) {
spin_unlock_bh(&ts->ts_state_lock);
iscsi_del_ts_from_active_list(ts);
if (!iscsit_global->in_shutdown)
iscsi_deallocate_extra_thread_sets();
iscsi_add_ts_to_inactive_list(ts);
spin_lock_bh(&ts->ts_state_lock);
}
if ((ts->status == ISCSI_THREAD_SET_RESET) &&
(ts->thread_clear & ISCSI_CLEAR_RX_THREAD))
complete(&ts->rx_restart_comp);
ts->thread_clear &= ~ISCSI_CLEAR_RX_THREAD;
spin_unlock_bh(&ts->ts_state_lock);
sleep:
ret = wait_for_completion_interruptible(&ts->rx_start_comp);
pr_info("%s: %s/%d (thread set %d) got %d waiting for rx_start_comp\n",
__func__, current->comm, task_pid_nr(current), ts->thread_id, ret);
if (ret != 0)
return NULL;
if (iscsi_signal_thread_pre_handler(ts) < 0)
return NULL;
if (!ts->conn) {
pr_err("struct iscsi_thread_set->conn is NULL for"
" thread_id: %d, going back to sleep\n", ts->thread_id);
goto sleep;
}
iscsi_check_to_add_additional_sets();
/*
* The RX Thread starts up the TX Thread and sleeps.
*/
spin_lock_bh(&ts->ts_state_lock);
ts->thread_clear |= ISCSI_CLEAR_RX_THREAD;
spin_unlock_bh(&ts->ts_state_lock);
complete(&ts->tx_start_comp);
wait_for_completion(&ts->tx_post_start_comp);
pr_info("%s/%d: returning connection %p for rx thread\n",
current->comm, task_pid_nr(current), ts->conn);
return ts->conn;
}
struct iscsi_conn *iscsi_tx_thread_pre_handler(struct iscsi_thread_set *ts)
{
int ret;
spin_lock_bh(&ts->ts_state_lock);
if (ts->create_threads) {
spin_unlock_bh(&ts->ts_state_lock);
goto sleep;
}
flush_signals(current);
if (ts->delay_inactive && (--ts->thread_count == 0)) {
spin_unlock_bh(&ts->ts_state_lock);
iscsi_del_ts_from_active_list(ts);
if (!iscsit_global->in_shutdown)
iscsi_deallocate_extra_thread_sets();
iscsi_add_ts_to_inactive_list(ts);
spin_lock_bh(&ts->ts_state_lock);
}
if ((ts->status == ISCSI_THREAD_SET_RESET) &&
(ts->thread_clear & ISCSI_CLEAR_TX_THREAD))
complete(&ts->tx_restart_comp);
ts->thread_clear &= ~ISCSI_CLEAR_TX_THREAD;
spin_unlock_bh(&ts->ts_state_lock);
sleep:
ret = wait_for_completion_interruptible(&ts->tx_start_comp);
if (ret != 0)
return NULL;
if (iscsi_signal_thread_pre_handler(ts) < 0)
return NULL;
if (!ts->conn) {
pr_err("struct iscsi_thread_set->conn is NULL for "
" thread_id: %d, going back to sleep\n",
ts->thread_id);
goto sleep;
}
iscsi_check_to_add_additional_sets();
/*
* From the TX thread, up the tx_post_start_comp that the RX Thread is
* sleeping on in iscsi_rx_thread_pre_handler(), then up the
* rx_post_start_comp that iscsi_activate_thread_set() is sleeping on.
*/
ts->thread_clear |= ISCSI_CLEAR_TX_THREAD;
complete(&ts->tx_post_start_comp);
complete(&ts->rx_post_start_comp);
spin_lock_bh(&ts->ts_state_lock);
ts->status = ISCSI_THREAD_SET_ACTIVE;
spin_unlock_bh(&ts->ts_state_lock);
return ts->conn;
}
extern int iscsi_allocate_thread_sets(u32 thread_pair_count)
{
int allocated_thread_pair_count = 0, i, thread_id;
struct iscsi_thread_set *ts = NULL;
for (i = 0; i < thread_pair_count; i++) {
ts = kzalloc(sizeof(struct iscsi_thread_set), GFP_KERNEL);
if (!ts) {
pr_err("Unable to allocate memory for"
" thread set.\n");
return allocated_thread_pair_count;
}
/*
* Locate the next available regision in the thread_set_bitmap
*/
spin_lock(&ts_bitmap_lock);
thread_id = bitmap_find_free_region(iscsit_global->ts_bitmap,
iscsit_global->ts_bitmap_count, get_order(1));
spin_unlock(&ts_bitmap_lock);
if (thread_id < 0) {
pr_err("bitmap_find_free_region() failed for"
" thread_set_bitmap\n");
kfree(ts);
return allocated_thread_pair_count;
}
ts->thread_id = thread_id;
ts->status = ISCSI_THREAD_SET_FREE;
INIT_LIST_HEAD(&ts->ts_list);
spin_lock_init(&ts->ts_state_lock);
init_completion(&ts->rx_post_start_comp);
init_completion(&ts->tx_post_start_comp);
init_completion(&ts->rx_restart_comp);
init_completion(&ts->tx_restart_comp);
init_completion(&ts->deferred_restart_comp);
init_completion(&ts->rx_start_comp);
init_completion(&ts->tx_start_comp);
init_completion(&ts->deferred_start_comp);
ts->create_threads = 1;
ts->tx_thread = kthread_run(iscsi_target_tx_thread, ts, "%s-%d",
ISCSI_TX_THREAD_NAME, thread_id);
if (IS_ERR(ts->tx_thread)) {
dump_stack();
pr_err("Unable to start iscsi_target_tx_thread\n");
break;
}
ts->rx_thread = kthread_run(iscsi_target_rx_thread, ts, "%s-%d",
ISCSI_RX_THREAD_NAME, thread_id);
if (IS_ERR(ts->rx_thread)) {
kthread_stop(ts->tx_thread);
pr_err("Unable to start iscsi_target_rx_thread\n");
break;
}
ts->deferred_thread = kthread_run(iscsi_target_deferred_thread, ts, "%s-%d",
ISCSI_DEFERRED_THREAD_NAME, thread_id);
if (IS_ERR(ts->deferred_thread)) {
kthread_stop(ts->rx_thread);
kthread_stop(ts->tx_thread);
pr_err("Unable to start iscsi_target_deferred_thread\n");
break;
}
ts->create_threads = 0;
iscsi_add_ts_to_inactive_list(ts);
allocated_thread_pair_count++;
}
pr_debug("Spawned %d thread set(s) (%d total threads).\n",
allocated_thread_pair_count, allocated_thread_pair_count * 3);
return allocated_thread_pair_count;
}
