path: root/platform/linux-generic/odp_schedule_sp.c

/* Copyright (c) 2016, Linaro Limited
 * All rights reserved.
 *
 * SPDX-License-Identifier:     BSD-3-Clause
 */

#include <string.h>
#include <odp/api/ticketlock.h>
#include <odp/api/thread.h>
#include <odp/api/time.h>
#include <odp/api/schedule.h>
#include <odp/api/shared_memory.h>
#include <odp_schedule_if.h>
#include <odp_debug_internal.h>
#include <odp_align_internal.h>
#include <odp_config_internal.h>
#include <odp_ring_internal.h>

#define NUM_THREAD        ODP_THREAD_COUNT_MAX
#define NUM_QUEUE         ODP_CONFIG_QUEUES
#define NUM_PKTIO         ODP_CONFIG_PKTIO_ENTRIES
#define NUM_ORDERED_LOCKS 1
#define NUM_PRIO          3
#define NUM_STATIC_GROUP  3
#define NUM_GROUP         (NUM_STATIC_GROUP + 9)
#define NUM_PKTIN         32
#define LOWEST_QUEUE_PRIO (NUM_PRIO - 2)
#define PKTIN_PRIO        (NUM_PRIO - 1)
#define CMD_QUEUE         0
#define CMD_PKTIO         1
#define GROUP_ALL         ODP_SCHED_GROUP_ALL
#define GROUP_WORKER      ODP_SCHED_GROUP_WORKER
#define GROUP_CONTROL     ODP_SCHED_GROUP_CONTROL
#define GROUP_PKTIN       GROUP_ALL

/* Maximum number of commands: one priority/group for all queues and pktios */
#define RING_SIZE         (ROUNDUP_POWER2_U32(NUM_QUEUE + NUM_PKTIO))
#define RING_MASK         (RING_SIZE - 1)

/* Ring size must be power of two */
ODP_STATIC_ASSERT(CHECK_IS_POWER2(RING_SIZE),
		  "Ring_size_is_not_power_of_two");

ODP_STATIC_ASSERT(NUM_ORDERED_LOCKS <= CONFIG_QUEUE_MAX_ORD_LOCKS,
		  "Too_many_ordered_locks");

struct sched_cmd_t;

struct sched_cmd_s {
	struct sched_cmd_t *next;
	uint32_t           index;
	uint32_t           ring_idx;
	int                type;
	int                prio;
	int                group;
	int                init;
	int                num_pktin;
	int                pktin_idx[NUM_PKTIN];
};

typedef struct sched_cmd_t {
	struct sched_cmd_s s;
	uint8_t            pad[ROUNDUP_CACHE_LINE(sizeof(struct sched_cmd_s)) -
			       sizeof(struct sched_cmd_s)];
} sched_cmd_t ODP_ALIGNED_CACHE;

typedef struct {
	/* Ring header */
	ring_t ring;

	/* Ring data: queue indexes */
	uint32_t ring_idx[RING_SIZE];

} prio_queue_t ODP_ALIGNED_CACHE;

typedef struct thr_group_t {
	/* A generation counter for fast comparison if groups have changed */
	odp_atomic_u32_t gen_cnt;

	/* Number of groups the thread belongs to */
	int num_group;

	/* The groups the thread belongs to */
	int group[NUM_GROUP];

} thr_group_t;

typedef struct sched_group_t {
	struct {
		odp_ticketlock_t  lock;

		/* All groups */
		struct {
			char          name[ODP_SCHED_GROUP_NAME_LEN + 1];
			odp_thrmask_t mask;
			int           allocated;
		} group[NUM_GROUP];

		/* Per thread group information */
		thr_group_t thr[NUM_THREAD];

	} s;

} sched_group_t ODP_ALIGNED_CACHE;

typedef struct {
	sched_cmd_t   queue_cmd[NUM_QUEUE];
	sched_cmd_t   pktio_cmd[NUM_PKTIO];
	prio_queue_t  prio_queue[NUM_GROUP][NUM_PRIO];
	sched_group_t sched_group;
	odp_shm_t     shm;
} sched_global_t;

typedef struct {
	sched_cmd_t *cmd;
	int          pause;
	int          thr_id;
	uint32_t     gen_cnt;
	int          num_group;
	int          group[NUM_GROUP];
} sched_local_t;

static sched_global_t *sched_global;
static __thread sched_local_t sched_local;

static inline uint32_t index_to_ring_idx(int pktio, uint32_t index)
{
	if (pktio)
		return (0x80000000 | index);

	return index;
}

static inline uint32_t index_from_ring_idx(uint32_t *index, uint32_t ring_idx)
{
	uint32_t pktio = ring_idx & 0x80000000;

	if (pktio)
		*index = ring_idx & (~0x80000000);
	else
		*index = ring_idx;

	return pktio;
}

static int init_global(void)
{
	int i, j;
	odp_shm_t shm;
	sched_group_t *sched_group = NULL;

	ODP_DBG("Using SP scheduler\n");

	shm = odp_shm_reserve("sp_scheduler",
			      sizeof(sched_global_t),
			      ODP_CACHE_LINE_SIZE, 0);

	sched_global = odp_shm_addr(shm);

	if (sched_global == NULL) {
		ODP_ERR("Schedule init: Shm reserve failed.\n");
		return -1;
	}

	memset(sched_global, 0, sizeof(sched_global_t));
	sched_global->shm = shm;

	for (i = 0; i < NUM_QUEUE; i++) {
		sched_global->queue_cmd[i].s.type     = CMD_QUEUE;
		sched_global->queue_cmd[i].s.index    = i;
		sched_global->queue_cmd[i].s.ring_idx = index_to_ring_idx(0, i);
	}

	for (i = 0; i < NUM_PKTIO; i++) {
		sched_global->pktio_cmd[i].s.type     = CMD_PKTIO;
		sched_global->pktio_cmd[i].s.index    = i;
		sched_global->pktio_cmd[i].s.ring_idx = index_to_ring_idx(1, i);
		sched_global->pktio_cmd[i].s.prio     = PKTIN_PRIO;
		sched_global->pktio_cmd[i].s.group    = GROUP_PKTIN;
	}

	for (i = 0; i < NUM_GROUP; i++)
		for (j = 0; j < NUM_PRIO; j++)
			ring_init(&sched_global->prio_queue[i][j].ring);

	sched_group = &sched_global->sched_group;
	odp_ticketlock_init(&sched_group->s.lock);

	for (i = 0; i < NUM_THREAD; i++)
		odp_atomic_init_u32(&sched_group->s.thr[i].gen_cnt, 0);

	strncpy(sched_group->s.group[GROUP_ALL].name, "__group_all",
		ODP_SCHED_GROUP_NAME_LEN);
	odp_thrmask_zero(&sched_group->s.group[GROUP_ALL].mask);
	sched_group->s.group[GROUP_ALL].allocated = 1;

	strncpy(sched_group->s.group[GROUP_WORKER].name, "__group_worker",
		ODP_SCHED_GROUP_NAME_LEN);
	odp_thrmask_zero(&sched_group->s.group[GROUP_WORKER].mask);
	sched_group->s.group[GROUP_WORKER].allocated = 1;

	strncpy(sched_group->s.group[GROUP_CONTROL].name, "__group_control",
		ODP_SCHED_GROUP_NAME_LEN);
	odp_thrmask_zero(&sched_group->s.group[GROUP_CONTROL].mask);
	sched_group->s.group[GROUP_CONTROL].allocated = 1;

	return 0;
}

static int init_local(void)
{
	memset(&sched_local, 0, sizeof(sched_local_t));
	sched_local.thr_id = odp_thread_id();

	return 0;
}

static int term_global(void)
{
	int qi, ret = 0;

	for (qi = 0; qi < NUM_QUEUE; qi++) {
		if (sched_global->queue_cmd[qi].s.init) {
			/* todo: dequeue until empty ? */
			sched_cb_queue_destroy_finalize(qi);
		}
	}

	ret = odp_shm_free(sched_global->shm);
	if (ret < 0) {
		ODP_ERR("Shm free failed for sp_scheduler");
		ret = -1;
	}

	return ret;
}

static int term_local(void)
{
	return 0;
}

static unsigned max_ordered_locks(void)
{
	return NUM_ORDERED_LOCKS;
}

static void add_group(sched_group_t *sched_group, int thr, int group)
{
	int num;
	uint32_t gen_cnt;
	thr_group_t *thr_group = &sched_group->s.thr[thr];

	num = thr_group->num_group;
	thr_group->group[num] = group;
	thr_group->num_group  = num + 1;
	gen_cnt = odp_atomic_load_u32(&thr_group->gen_cnt);
	odp_atomic_store_u32(&thr_group->gen_cnt, gen_cnt + 1);
}

static void remove_group(sched_group_t *sched_group, int thr, int group)
{
	int i, num;
	int found = 0;
	thr_group_t *thr_group = &sched_group->s.thr[thr];

	num = thr_group->num_group;

	for (i = 0; i < num; i++) {
		if (thr_group->group[i] == group) {
			found = 1;

			for (; i < num - 1; i++)
				thr_group->group[i] = thr_group->group[i + 1];

			break;
		}
	}

	if (found) {
		uint32_t gen_cnt;

		thr_group->num_group = num - 1;
		gen_cnt = odp_atomic_load_u32(&thr_group->gen_cnt);
		odp_atomic_store_u32(&thr_group->gen_cnt, gen_cnt + 1);
	}
}

static int thr_add(odp_schedule_group_t group, int thr)
{
	sched_group_t *sched_group = &sched_global->sched_group;

	if (group < 0 || group >= NUM_GROUP)
		return -1;

	if (thr < 0 || thr >= NUM_THREAD)
		return -1;

	odp_ticketlock_lock(&sched_group->s.lock);

	if (!sched_group->s.group[group].allocated) {
		odp_ticketlock_unlock(&sched_group->s.lock);
		return -1;
	}

	odp_thrmask_set(&sched_group->s.group[group].mask, thr);
	add_group(sched_group, thr, group);

	odp_ticketlock_unlock(&sched_group->s.lock);

	return 0;
}

static int thr_rem(odp_schedule_group_t group, int thr)
{
	sched_group_t *sched_group = &sched_global->sched_group;

	if (group < 0 || group >= NUM_GROUP)
		return -1;

	odp_ticketlock_lock(&sched_group->s.lock);

	if (!sched_group->s.group[group].allocated) {
		odp_ticketlock_unlock(&sched_group->s.lock);
		return -1;
	}

	odp_thrmask_clr(&sched_group->s.group[group].mask, thr);

	remove_group(sched_group, thr, group);

	odp_ticketlock_unlock(&sched_group->s.lock);

	return 0;
}

static int num_grps(void)
{
	return NUM_GROUP - NUM_STATIC_GROUP;
}

static int init_queue(uint32_t qi, const odp_schedule_param_t *sched_param)
{
	sched_group_t *sched_group = &sched_global->sched_group;
	odp_schedule_group_t group = sched_param->group;
	int prio = 0;

	if (group < 0 || group >= NUM_GROUP)
		return -1;

	if (!sched_group->s.group[group].allocated)
		return -1;

	if (sched_param->prio > 0)
		prio = LOWEST_QUEUE_PRIO;

	sched_global->queue_cmd[qi].s.prio  = prio;
	sched_global->queue_cmd[qi].s.group = group;
	sched_global->queue_cmd[qi].s.init  = 1;

	return 0;
}

static void destroy_queue(uint32_t qi)
{
	sched_global->queue_cmd[qi].s.prio  = 0;
	sched_global->queue_cmd[qi].s.group = 0;
	sched_global->queue_cmd[qi].s.init  = 0;
}

static inline void add_tail(sched_cmd_t *cmd)
{
	prio_queue_t *prio_queue;
	int group    = cmd->s.group;
	int prio     = cmd->s.prio;
	uint32_t idx = cmd->s.ring_idx;

	prio_queue = &sched_global->prio_queue[group][prio];
	ring_enq(&prio_queue->ring, RING_MASK, idx);
}

static inline sched_cmd_t *rem_head(int group, int prio)
{
	prio_queue_t *prio_queue;
	uint32_t ring_idx, index;
	int pktio;

	prio_queue = &sched_global->prio_queue[group][prio];
	ring_idx = ring_deq(&prio_queue->ring, RING_MASK);

	if (ring_idx == RING_EMPTY)
		return NULL;

	pktio = index_from_ring_idx(&index, ring_idx);

	if (pktio)
		return &sched_global->pktio_cmd[index];

	return &sched_global->queue_cmd[index];
}

static int sched_queue(uint32_t qi)
{
	sched_cmd_t *cmd;

	cmd = &sched_global->queue_cmd[qi];
	add_tail(cmd);

	return 0;
}

static int ord_enq_multi(queue_t q_int, void *buf_hdr[], int num,
			 int *ret)
{
	(void)q_int;
	(void)buf_hdr;
	(void)num;
	(void)ret;

	/* didn't consume the events */
	return 0;
}

static void pktio_start(int pktio_index, int num, int pktin_idx[])
{
	int i;
	sched_cmd_t *cmd;

	ODP_DBG("pktio index: %i, %i pktin queues %i\n",
		pktio_index, num, pktin_idx[0]);

	cmd = &sched_global->pktio_cmd[pktio_index];

	if (num > NUM_PKTIN)
		ODP_ABORT("Supports only %i pktin queues per interface\n",
			  NUM_PKTIN);

	for (i = 0; i < num; i++)
		cmd->s.pktin_idx[i] = pktin_idx[i];

	cmd->s.num_pktin = num;

	add_tail(cmd);
}

static inline sched_cmd_t *sched_cmd(void)
{
	int prio, i;
	int thr = sched_local.thr_id;
	sched_group_t *sched_group = &sched_global->sched_group;
	thr_group_t *thr_group = &sched_group->s.thr[thr];
	uint32_t gen_cnt;

	/* There's no matching store_rel since the value is updated while
	 * holding a lock */
	gen_cnt = odp_atomic_load_acq_u32(&thr_group->gen_cnt);

	/* Check if groups have changed and need to be read again */
	if (odp_unlikely(gen_cnt != sched_local.gen_cnt)) {
		int num_grp;

		odp_ticketlock_lock(&sched_group->s.lock);

		num_grp = thr_group->num_group;
		gen_cnt = odp_atomic_load_u32(&thr_group->gen_cnt);

		for (i = 0; i < num_grp; i++)
			sched_local.group[i] = thr_group->group[i];

		odp_ticketlock_unlock(&sched_group->s.lock);

		sched_local.num_group = num_grp;
		sched_local.gen_cnt   = gen_cnt;
	}

	for (i = 0; i < sched_local.num_group; i++) {
		for (prio = 0; prio < NUM_PRIO; prio++) {
			sched_cmd_t *cmd = rem_head(sched_local.group[i], prio);

			if (cmd)
				return cmd;
		}
	}

	return NULL;
}

static uint64_t schedule_wait_time(uint64_t ns)
{
	return ns;
}

static int schedule_multi(odp_queue_t *from, uint64_t wait,
			  odp_event_t events[], int max_events ODP_UNUSED)
{
	odp_time_t t1;
	int update_t1 = 1;

	if (sched_local.cmd) {
		/* Continue scheduling if queue is not empty */
		if (sched_cb_queue_empty(sched_local.cmd->s.index) == 0)
			add_tail(sched_local.cmd);

		sched_local.cmd = NULL;
	}

	if (odp_unlikely(sched_local.pause))
		return 0;

	while (1) {
		sched_cmd_t *cmd;
		uint32_t qi;
		int num;

		cmd = sched_cmd();

		if (cmd && cmd->s.type == CMD_PKTIO) {
			if (sched_cb_pktin_poll(cmd->s.index, cmd->s.num_pktin,
						cmd->s.pktin_idx)) {
				/* Pktio stopped or closed. */
				sched_cb_pktio_stop_finalize(cmd->s.index);
			} else {
				/* Continue polling pktio. */
				add_tail(cmd);
			}

			/* run wait parameter checks under */
			cmd = NULL;
		}

		if (cmd == NULL) {
			/* All priority queues are empty */
			if (wait == ODP_SCHED_NO_WAIT)
				return 0;

			if (wait == ODP_SCHED_WAIT)
				continue;

			if (update_t1) {
				t1 = odp_time_sum(odp_time_local(),
						  odp_time_local_from_ns(wait));
				update_t1 = 0;
				continue;
			}

			if (odp_time_cmp(odp_time_local(), t1) < 0)
				continue;

			return 0;
		}

		qi  = cmd->s.index;
		num = sched_cb_queue_deq_multi(qi, events, 1);

		if (num > 0) {
			sched_local.cmd = cmd;

			if (from)
				*from = sched_cb_queue_handle(qi);

			return num;
		}

		if (num < 0) {
			/* Destroyed queue */
			sched_cb_queue_destroy_finalize(qi);
			continue;
		}

		if (num == 0) {
			/* Remove empty queue from scheduling. A dequeue
			 * operation to on an already empty queue moves
			 * it to NOTSCHED state and sched_queue() will
			 * be called on next enqueue. */
			continue;
		}
	}
}

static odp_event_t schedule(odp_queue_t *from, uint64_t wait)
{
	odp_event_t ev;

	if (schedule_multi(from, wait, &ev, 1) > 0)
		return ev;

	return ODP_EVENT_INVALID;
}

static void schedule_pause(void)
{
	sched_local.pause = 1;
}

static void schedule_resume(void)
{
	sched_local.pause = 0;
}

static void schedule_release_atomic(void)
{
}

static void schedule_release_ordered(void)
{
}

static void schedule_prefetch(int num)
{
	(void)num;
}

static int schedule_num_prio(void)
{
	/* Lowest priority is used for pktin polling and is internal
	 * to the scheduler */
	return NUM_PRIO - 1;
}

static odp_schedule_group_t schedule_group_create(const char *name,
						  const odp_thrmask_t *thrmask)
{
	odp_schedule_group_t group = ODP_SCHED_GROUP_INVALID;
	sched_group_t *sched_group = &sched_global->sched_group;
	int i;

	odp_ticketlock_lock(&sched_group->s.lock);

	for (i = NUM_STATIC_GROUP; i < NUM_GROUP; i++) {
		if (!sched_group->s.group[i].allocated) {
			char *grp_name = sched_group->s.group[i].name;

			if (name == NULL) {
				grp_name[0] = 0;
			} else {
				strncpy(grp_name, name,
					ODP_SCHED_GROUP_NAME_LEN - 1);
				grp_name[ODP_SCHED_GROUP_NAME_LEN - 1] = 0;
			}
			odp_thrmask_copy(&sched_group->s.group[i].mask,
					 thrmask);
			sched_group->s.group[i].allocated = 1;
			group = i;
			break;
		}
	}

	odp_ticketlock_unlock(&sched_group->s.lock);

	return group;
}

static int schedule_group_destroy(odp_schedule_group_t group)
{
	sched_group_t *sched_group = &sched_global->sched_group;

	if (group < NUM_STATIC_GROUP || group >= NUM_GROUP)
		return -1;

	odp_ticketlock_lock(&sched_group->s.lock);

	if (!sched_group->s.group[group].allocated) {
		odp_ticketlock_unlock(&sched_group->s.lock);
		return -1;
	}

	memset(&sched_group->s.group[group], 0,
	       sizeof(sched_group->s.group[0]));

	odp_ticketlock_unlock(&sched_group->s.lock);

	return 0;
}

static odp_schedule_group_t schedule_group_lookup(const char *name)
{
	odp_schedule_group_t group = ODP_SCHED_GROUP_INVALID;
	sched_group_t *sched_group = &sched_global->sched_group;
	int i;

	odp_ticketlock_lock(&sched_group->s.lock);

	for (i = NUM_STATIC_GROUP; i < NUM_GROUP; i++) {
		if (sched_group->s.group[i].allocated &&
		    strcmp(sched_group->s.group[i].name, name) == 0) {
			group = i;
			break;
		}
	}

	odp_ticketlock_unlock(&sched_group->s.lock);
	return group;
}

static int schedule_group_join(odp_schedule_group_t group,
			       const odp_thrmask_t *thrmask)
{
	int thr;
	sched_group_t *sched_group = &sched_global->sched_group;

	if (group < 0 || group >= NUM_GROUP)
		return -1;

	thr = odp_thrmask_first(thrmask);

	odp_ticketlock_lock(&sched_group->s.lock);

	if (!sched_group->s.group[group].allocated) {
		odp_ticketlock_unlock(&sched_group->s.lock);
		return -1;
	}

	odp_thrmask_or(&sched_group->s.group[group].mask,
		       &sched_group->s.group[group].mask,
		       thrmask);

	while (thr >= 0) {
		add_group(sched_group, thr, group);
		thr = odp_thrmask_next(thrmask, thr);
	}

	odp_ticketlock_unlock(&sched_group->s.lock);

	return 0;
}

static int schedule_group_leave(odp_schedule_group_t group,
				const odp_thrmask_t *thrmask)
{
	int thr;
	sched_group_t *sched_group = &sched_global->sched_group;
	odp_thrmask_t *all = &sched_group->s.group[GROUP_ALL].mask;
	odp_thrmask_t not;

	if (group < 0 || group >= NUM_GROUP)
		return -1;

	thr = odp_thrmask_first(thrmask);

	odp_ticketlock_lock(&sched_group->s.lock);

	if (!sched_group->s.group[group].allocated) {
		odp_ticketlock_unlock(&sched_group->s.lock);
		return -1;
	}

	odp_thrmask_xor(&not, thrmask, all);
	odp_thrmask_and(&sched_group->s.group[group].mask,
			&sched_group->s.group[group].mask,
			&not);

	while (thr >= 0) {
		remove_group(sched_group, thr, group);
		thr = odp_thrmask_next(thrmask, thr);
	}

	odp_ticketlock_unlock(&sched_group->s.lock);

	return 0;
}

static int schedule_group_thrmask(odp_schedule_group_t group,
				  odp_thrmask_t *thrmask)
{
	sched_group_t *sched_group = &sched_global->sched_group;

	if (group < 0 || group >= NUM_GROUP)
		return -1;

	odp_ticketlock_lock(&sched_group->s.lock);

	if (!sched_group->s.group[group].allocated) {
		odp_ticketlock_unlock(&sched_group->s.lock);
		return -1;
	}

	*thrmask = sched_group->s.group[group].mask;

	odp_ticketlock_unlock(&sched_group->s.lock);

	return 0;
}

static int schedule_group_info(odp_schedule_group_t group,
			       odp_schedule_group_info_t *info)
{
	sched_group_t *sched_group = &sched_global->sched_group;

	if (group < 0 || group >= NUM_GROUP)
		return -1;

	odp_ticketlock_lock(&sched_group->s.lock);

	if (!sched_group->s.group[group].allocated) {
		odp_ticketlock_unlock(&sched_group->s.lock);
		return -1;
	}

	info->name    = sched_group->s.group[group].name;
	info->thrmask = sched_group->s.group[group].mask;

	odp_ticketlock_unlock(&sched_group->s.lock);

	return 0;
}

static void schedule_order_lock(unsigned lock_index)
{
	(void)lock_index;
}

static void schedule_order_unlock(unsigned lock_index)
{
	(void)lock_index;
}

static void order_lock(void)
{
}

static void order_unlock(void)
{
}

/* Fill in scheduler interface */
const schedule_fn_t schedule_sp_fn = {
	.status_sync   = 0,
	.pktio_start   = pktio_start,
	.thr_add       = thr_add,
	.thr_rem       = thr_rem,
	.num_grps      = num_grps,
	.init_queue    = init_queue,
	.destroy_queue = destroy_queue,
	.sched_queue   = sched_queue,
	.ord_enq_multi = ord_enq_multi,
	.init_global   = init_global,
	.term_global   = term_global,
	.init_local    = init_local,
	.term_local    = term_local,
	.order_lock    = order_lock,
	.order_unlock  = order_unlock,
	.max_ordered_locks = max_ordered_locks,
	.unsched_queue = NULL,
	.save_context  = NULL
};

/* Fill in scheduler API calls */
const schedule_api_t schedule_sp_api = {
	.schedule_wait_time       = schedule_wait_time,
	.schedule                 = schedule,
	.schedule_multi           = schedule_multi,
	.schedule_pause           = schedule_pause,
	.schedule_resume          = schedule_resume,
	.schedule_release_atomic  = schedule_release_atomic,
	.schedule_release_ordered = schedule_release_ordered,
	.schedule_prefetch        = schedule_prefetch,
	.schedule_num_prio        = schedule_num_prio,
	.schedule_group_create    = schedule_group_create,
	.schedule_group_destroy   = schedule_group_destroy,
	.schedule_group_lookup    = schedule_group_lookup,
	.schedule_group_join      = schedule_group_join,
	.schedule_group_leave     = schedule_group_leave,
	.schedule_group_thrmask   = schedule_group_thrmask,
	.schedule_group_info      = schedule_group_info,
	.schedule_order_lock      = schedule_order_lock,
	.schedule_order_unlock    = schedule_order_unlock
};