}
}
+/**
+ * LNet message drop simulation
+ */
+
/**
* Add a new drop rule to LNet
* There is no check for duplicated drop rule, all rules will be checked for
{
struct lnet_drop_rule *rule;
- if (!attr->u.drop.da_rate == !attr->u.drop.da_interval) {
- CDEBUG(D_NET, "invalid rate %d or interval %d\n",
+ if (attr->u.drop.da_rate & attr->u.drop.da_interval) {
+ CDEBUG(D_NET, "please provide either drop rate or drop interval, but not both at the same time %d/%d\n",
attr->u.drop.da_rate, attr->u.drop.da_interval);
return -EINVAL;
}
return drop;
}
+/**
+ * LNet Delay Simulation
+ */
+/** timestamp (second) to send delayed message */
+#define msg_delay_send msg_ev.hdr_data
+
+struct lnet_delay_rule {
+ /** link chain on the_lnet.ln_delay_rules */
+ struct list_head dl_link;
+ /** link chain on delay_dd.dd_sched_rules */
+ struct list_head dl_sched_link;
+ /** attributes of this rule */
+ struct lnet_fault_attr dl_attr;
+ /** lock to protect \a below members */
+ spinlock_t dl_lock;
+ /** refcount of delay rule */
+ atomic_t dl_refcount;
+ /**
+ * the message sequence to delay, which means message is delayed when
+ * dl_stat.fs_count == dl_delay_at
+ */
+ unsigned long dl_delay_at;
+ /**
+ * seconds to delay the next message, it's exclusive with dl_delay_at
+ */
+ unsigned long dl_delay_time;
+ /** baseline to caculate dl_delay_time */
+ unsigned long dl_time_base;
+ /** jiffies to send the next delayed message */
+ unsigned long dl_msg_send;
+ /** delayed message list */
+ struct list_head dl_msg_list;
+ /** statistic of delayed messages */
+ struct lnet_fault_stat dl_stat;
+ /** timer to wakeup delay_daemon */
+ struct timer_list dl_timer;
+};
+
+struct delay_daemon_data {
+ /** serialise rule add/remove */
+ struct mutex dd_mutex;
+ /** protect rules on \a dd_sched_rules */
+ spinlock_t dd_lock;
+ /** scheduled delay rules (by timer) */
+ struct list_head dd_sched_rules;
+ /** daemon thread sleeps at here */
+ wait_queue_head_t dd_waitq;
+ /** controller (lctl command) wait at here */
+ wait_queue_head_t dd_ctl_waitq;
+ /** daemon is running */
+ unsigned int dd_running;
+ /** daemon stopped */
+ unsigned int dd_stopped;
+};
+
+static struct delay_daemon_data delay_dd;
+
+static unsigned long
+round_timeout(unsigned long timeout)
+{
+ return cfs_time_seconds((unsigned int)
+ cfs_duration_sec(cfs_time_sub(timeout, 0)) + 1);
+}
+
+static void
+delay_rule_decref(struct lnet_delay_rule *rule)
+{
+ if (atomic_dec_and_test(&rule->dl_refcount)) {
+ LASSERT(list_empty(&rule->dl_sched_link));
+ LASSERT(list_empty(&rule->dl_msg_list));
+ LASSERT(list_empty(&rule->dl_link));
+
+ CFS_FREE_PTR(rule);
+ }
+}
+
+/**
+ * check source/destination NID, portal, message type and delay rate,
+ * decide whether should delay this message or not
+ */
+static bool
+delay_rule_match(struct lnet_delay_rule *rule, lnet_nid_t src,
+ lnet_nid_t dst, unsigned int type, unsigned int portal,
+ struct lnet_msg *msg)
+{
+ struct lnet_fault_attr *attr = &rule->dl_attr;
+ bool delay;
+
+ if (!lnet_fault_attr_match(attr, src, dst, type, portal))
+ return false;
+
+ /* match this rule, check delay rate now */
+ spin_lock(&rule->dl_lock);
+ if (rule->dl_delay_time) { /* time based delay */
+ unsigned long now = cfs_time_current();
+
+ rule->dl_stat.fs_count++;
+ delay = cfs_time_aftereq(now, rule->dl_delay_time);
+ if (delay) {
+ if (cfs_time_after(now, rule->dl_time_base))
+ rule->dl_time_base = now;
+
+ rule->dl_delay_time = rule->dl_time_base +
+ cfs_time_seconds(cfs_rand() %
+ attr->u.delay.la_interval);
+ rule->dl_time_base += cfs_time_seconds(attr->u.delay.la_interval);
+
+ CDEBUG(D_NET, "Delay Rule %s->%s: next delay : %lu\n",
+ libcfs_nid2str(attr->fa_src),
+ libcfs_nid2str(attr->fa_dst),
+ rule->dl_delay_time);
+ }
+
+ } else { /* rate based delay */
+ delay = rule->dl_stat.fs_count++ == rule->dl_delay_at;
+ /* generate the next random rate sequence */
+ if (!do_div(rule->dl_stat.fs_count, attr->u.delay.la_rate)) {
+ rule->dl_delay_at = rule->dl_stat.fs_count +
+ cfs_rand() % attr->u.delay.la_rate;
+ CDEBUG(D_NET, "Delay Rule %s->%s: next delay: %lu\n",
+ libcfs_nid2str(attr->fa_src),
+ libcfs_nid2str(attr->fa_dst), rule->dl_delay_at);
+ }
+ }
+
+ if (!delay) {
+ spin_unlock(&rule->dl_lock);
+ return false;
+ }
+
+ /* delay this message, update counters */
+ lnet_fault_stat_inc(&rule->dl_stat, type);
+ rule->dl_stat.u.delay.ls_delayed++;
+
+ list_add_tail(&msg->msg_list, &rule->dl_msg_list);
+ msg->msg_delay_send = round_timeout(
+ cfs_time_shift(attr->u.delay.la_latency));
+ if (rule->dl_msg_send == -1) {
+ rule->dl_msg_send = msg->msg_delay_send;
+ mod_timer(&rule->dl_timer, rule->dl_msg_send);
+ }
+
+ spin_unlock(&rule->dl_lock);
+ return true;
+}
+
+/**
+ * check if \a msg can match any Delay Rule, receiving of this message
+ * will be delayed if there is a match.
+ */
+bool
+lnet_delay_rule_match_locked(lnet_hdr_t *hdr, struct lnet_msg *msg)
+{
+ struct lnet_delay_rule *rule;
+ lnet_nid_t src = le64_to_cpu(hdr->src_nid);
+ lnet_nid_t dst = le64_to_cpu(hdr->dest_nid);
+ unsigned int typ = le32_to_cpu(hdr->type);
+ unsigned int ptl = -1;
+
+ /* NB: called with hold of lnet_net_lock */
+
+ /**
+ * NB: if Portal is specified, then only PUT and GET will be
+ * filtered by delay rule
+ */
+ if (typ == LNET_MSG_PUT)
+ ptl = le32_to_cpu(hdr->msg.put.ptl_index);
+ else if (typ == LNET_MSG_GET)
+ ptl = le32_to_cpu(hdr->msg.get.ptl_index);
+
+ list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
+ if (delay_rule_match(rule, src, dst, typ, ptl, msg))
+ return true;
+ }
+
+ return false;
+}
+
+/** check out delayed messages for send */
+static void
+delayed_msg_check(struct lnet_delay_rule *rule, bool all,
+ struct list_head *msg_list)
+{
+ struct lnet_msg *msg;
+ struct lnet_msg *tmp;
+ unsigned long now = cfs_time_current();
+
+ if (!all && rule->dl_msg_send > now)
+ return;
+
+ spin_lock(&rule->dl_lock);
+ list_for_each_entry_safe(msg, tmp, &rule->dl_msg_list, msg_list) {
+ if (!all && msg->msg_delay_send > now)
+ break;
+
+ msg->msg_delay_send = 0;
+ list_move_tail(&msg->msg_list, msg_list);
+ }
+
+ if (list_empty(&rule->dl_msg_list)) {
+ del_timer(&rule->dl_timer);
+ rule->dl_msg_send = -1;
+
+ } else if (!list_empty(msg_list)) {
+ /*
+ * dequeued some timedout messages, update timer for the
+ * next delayed message on rule
+ */
+ msg = list_entry(rule->dl_msg_list.next,
+ struct lnet_msg, msg_list);
+ rule->dl_msg_send = msg->msg_delay_send;
+ mod_timer(&rule->dl_timer, rule->dl_msg_send);
+ }
+ spin_unlock(&rule->dl_lock);
+}
+
+static void
+delayed_msg_process(struct list_head *msg_list, bool drop)
+{
+ struct lnet_msg *msg;
+
+ while (!list_empty(msg_list)) {
+ struct lnet_ni *ni;
+ int cpt;
+ int rc;
+
+ msg = list_entry(msg_list->next, struct lnet_msg, msg_list);
+ LASSERT(msg->msg_rxpeer);
+
+ ni = msg->msg_rxpeer->lp_ni;
+ cpt = msg->msg_rx_cpt;
+
+ list_del_init(&msg->msg_list);
+ if (drop) {
+ rc = -ECANCELED;
+
+ } else if (!msg->msg_routing) {
+ rc = lnet_parse_local(ni, msg);
+ if (!rc)
+ continue;
+
+ } else {
+ lnet_net_lock(cpt);
+ rc = lnet_parse_forward_locked(ni, msg);
+ lnet_net_unlock(cpt);
+
+ switch (rc) {
+ case LNET_CREDIT_OK:
+ lnet_ni_recv(ni, msg->msg_private, msg, 0,
+ 0, msg->msg_len, msg->msg_len);
+ case LNET_CREDIT_WAIT:
+ continue;
+ default: /* failures */
+ break;
+ }
+ }
+
+ lnet_drop_message(ni, cpt, msg->msg_private, msg->msg_len);
+ lnet_finalize(ni, msg, rc);
+ }
+}
+
+/**
+ * Process delayed messages for scheduled rules
+ * This function can either be called by delay_rule_daemon, or by lnet_finalise
+ */
+void
+lnet_delay_rule_check(void)
+{
+ struct lnet_delay_rule *rule;
+ struct list_head msgs;
+
+ INIT_LIST_HEAD(&msgs);
+ while (1) {
+ if (list_empty(&delay_dd.dd_sched_rules))
+ break;
+
+ spin_lock_bh(&delay_dd.dd_lock);
+ if (list_empty(&delay_dd.dd_sched_rules)) {
+ spin_unlock_bh(&delay_dd.dd_lock);
+ break;
+ }
+
+ rule = list_entry(delay_dd.dd_sched_rules.next,
+ struct lnet_delay_rule, dl_sched_link);
+ list_del_init(&rule->dl_sched_link);
+ spin_unlock_bh(&delay_dd.dd_lock);
+
+ delayed_msg_check(rule, false, &msgs);
+ delay_rule_decref(rule); /* -1 for delay_dd.dd_sched_rules */
+ }
+
+ if (!list_empty(&msgs))
+ delayed_msg_process(&msgs, false);
+}
+
+/** daemon thread to handle delayed messages */
+static int
+lnet_delay_rule_daemon(void *arg)
+{
+ delay_dd.dd_running = 1;
+ wake_up(&delay_dd.dd_ctl_waitq);
+
+ while (delay_dd.dd_running) {
+ wait_event_interruptible(delay_dd.dd_waitq,
+ !delay_dd.dd_running ||
+ !list_empty(&delay_dd.dd_sched_rules));
+ lnet_delay_rule_check();
+ }
+
+ /* in case more rules have been enqueued after my last check */
+ lnet_delay_rule_check();
+ delay_dd.dd_stopped = 1;
+ wake_up(&delay_dd.dd_ctl_waitq);
+
+ return 0;
+}
+
+static void
+delay_timer_cb(unsigned long arg)
+{
+ struct lnet_delay_rule *rule = (struct lnet_delay_rule *)arg;
+
+ spin_lock_bh(&delay_dd.dd_lock);
+ if (list_empty(&rule->dl_sched_link) && delay_dd.dd_running) {
+ atomic_inc(&rule->dl_refcount);
+ list_add_tail(&rule->dl_sched_link, &delay_dd.dd_sched_rules);
+ wake_up(&delay_dd.dd_waitq);
+ }
+ spin_unlock_bh(&delay_dd.dd_lock);
+}
+
+/**
+ * Add a new delay rule to LNet
+ * There is no check for duplicated delay rule, all rules will be checked for
+ * incoming message.
+ */
+int
+lnet_delay_rule_add(struct lnet_fault_attr *attr)
+{
+ struct lnet_delay_rule *rule;
+ int rc = 0;
+
+ if (attr->u.delay.la_rate & attr->u.delay.la_interval) {
+ CDEBUG(D_NET, "please provide either delay rate or delay interval, but not both at the same time %d/%d\n",
+ attr->u.delay.la_rate, attr->u.delay.la_interval);
+ return -EINVAL;
+ }
+
+ if (!attr->u.delay.la_latency) {
+ CDEBUG(D_NET, "delay latency cannot be zero\n");
+ return -EINVAL;
+ }
+
+ if (lnet_fault_attr_validate(attr))
+ return -EINVAL;
+
+ CFS_ALLOC_PTR(rule);
+ if (!rule)
+ return -ENOMEM;
+
+ mutex_lock(&delay_dd.dd_mutex);
+ if (!delay_dd.dd_running) {
+ struct task_struct *task;
+
+ /**
+ * NB: although LND threads will process delayed message
+ * in lnet_finalize, but there is no guarantee that LND
+ * threads will be waken up if no other message needs to
+ * be handled.
+ * Only one daemon thread, performance is not the concern
+ * of this simualation module.
+ */
+ task = kthread_run(lnet_delay_rule_daemon, NULL, "lnet_dd");
+ if (IS_ERR(task)) {
+ rc = PTR_ERR(task);
+ goto failed;
+ }
+ wait_event(delay_dd.dd_ctl_waitq, delay_dd.dd_running);
+ }
+
+ init_timer(&rule->dl_timer);
+ rule->dl_timer.function = delay_timer_cb;
+ rule->dl_timer.data = (unsigned long)rule;
+
+ spin_lock_init(&rule->dl_lock);
+ INIT_LIST_HEAD(&rule->dl_msg_list);
+ INIT_LIST_HEAD(&rule->dl_sched_link);
+
+ rule->dl_attr = *attr;
+ if (attr->u.delay.la_interval) {
+ rule->dl_time_base = cfs_time_shift(attr->u.delay.la_interval);
+ rule->dl_delay_time = cfs_time_shift(cfs_rand() %
+ attr->u.delay.la_interval);
+ } else {
+ rule->dl_delay_at = cfs_rand() % attr->u.delay.la_rate;
+ }
+
+ rule->dl_msg_send = -1;
+
+ lnet_net_lock(LNET_LOCK_EX);
+ atomic_set(&rule->dl_refcount, 1);
+ list_add(&rule->dl_link, &the_lnet.ln_delay_rules);
+ lnet_net_unlock(LNET_LOCK_EX);
+
+ CDEBUG(D_NET, "Added delay rule: src %s, dst %s, rate %d\n",
+ libcfs_nid2str(attr->fa_src), libcfs_nid2str(attr->fa_src),
+ attr->u.delay.la_rate);
+
+ mutex_unlock(&delay_dd.dd_mutex);
+ return 0;
+failed:
+ mutex_unlock(&delay_dd.dd_mutex);
+ CFS_FREE_PTR(rule);
+ return rc;
+}
+
+/**
+ * Remove matched Delay Rules from lnet, if \a shutdown is true or both \a src
+ * and \a dst are zero, all rules will be removed, otherwise only matched rules
+ * will be removed.
+ * If \a src is zero, then all rules have \a dst as destination will be remove
+ * If \a dst is zero, then all rules have \a src as source will be removed
+ *
+ * When a delay rule is removed, all delayed messages of this rule will be
+ * processed immediately.
+ */
+int
+lnet_delay_rule_del(lnet_nid_t src, lnet_nid_t dst, bool shutdown)
+{
+ struct lnet_delay_rule *rule;
+ struct lnet_delay_rule *tmp;
+ struct list_head rule_list;
+ struct list_head msg_list;
+ int n = 0;
+ bool cleanup;
+
+ INIT_LIST_HEAD(&rule_list);
+ INIT_LIST_HEAD(&msg_list);
+
+ if (shutdown) {
+ src = 0;
+ dst = 0;
+ }
+
+ mutex_lock(&delay_dd.dd_mutex);
+ lnet_net_lock(LNET_LOCK_EX);
+
+ list_for_each_entry_safe(rule, tmp, &the_lnet.ln_delay_rules, dl_link) {
+ if (rule->dl_attr.fa_src != src && src)
+ continue;
+
+ if (rule->dl_attr.fa_dst != dst && dst)
+ continue;
+
+ CDEBUG(D_NET, "Remove delay rule: src %s->dst: %s (1/%d, %d)\n",
+ libcfs_nid2str(rule->dl_attr.fa_src),
+ libcfs_nid2str(rule->dl_attr.fa_dst),
+ rule->dl_attr.u.delay.la_rate,
+ rule->dl_attr.u.delay.la_interval);
+ /* refcount is taken over by rule_list */
+ list_move(&rule->dl_link, &rule_list);
+ }
+
+ /* check if we need to shutdown delay_daemon */
+ cleanup = list_empty(&the_lnet.ln_delay_rules) &&
+ !list_empty(&rule_list);
+ lnet_net_unlock(LNET_LOCK_EX);
+
+ list_for_each_entry_safe(rule, tmp, &rule_list, dl_link) {
+ list_del_init(&rule->dl_link);
+
+ del_timer_sync(&rule->dl_timer);
+ delayed_msg_check(rule, true, &msg_list);
+ delay_rule_decref(rule); /* -1 for the_lnet.ln_delay_rules */
+ n++;
+ }
+
+ if (cleanup) { /* no more delay rule, shutdown delay_daemon */
+ LASSERT(delay_dd.dd_running);
+ delay_dd.dd_running = 0;
+ wake_up(&delay_dd.dd_waitq);
+
+ while (!delay_dd.dd_stopped)
+ wait_event(delay_dd.dd_ctl_waitq, delay_dd.dd_stopped);
+ }
+ mutex_unlock(&delay_dd.dd_mutex);
+
+ if (!list_empty(&msg_list))
+ delayed_msg_process(&msg_list, shutdown);
+
+ return n;
+}
+
+/**
+ * List Delay Rule at position of \a pos
+ */
+int
+lnet_delay_rule_list(int pos, struct lnet_fault_attr *attr,
+ struct lnet_fault_stat *stat)
+{
+ struct lnet_delay_rule *rule;
+ int cpt;
+ int i = 0;
+ int rc = -ENOENT;
+
+ cpt = lnet_net_lock_current();
+ list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
+ if (i++ < pos)
+ continue;
+
+ spin_lock(&rule->dl_lock);
+ *attr = rule->dl_attr;
+ *stat = rule->dl_stat;
+ spin_unlock(&rule->dl_lock);
+ rc = 0;
+ break;
+ }
+
+ lnet_net_unlock(cpt);
+ return rc;
+}
+
+/**
+ * reset counters for all Delay Rules
+ */
+void
+lnet_delay_rule_reset(void)
+{
+ struct lnet_delay_rule *rule;
+ int cpt;
+
+ cpt = lnet_net_lock_current();
+
+ list_for_each_entry(rule, &the_lnet.ln_delay_rules, dl_link) {
+ struct lnet_fault_attr *attr = &rule->dl_attr;
+
+ spin_lock(&rule->dl_lock);
+
+ memset(&rule->dl_stat, 0, sizeof(rule->dl_stat));
+ if (attr->u.delay.la_rate) {
+ rule->dl_delay_at = cfs_rand() % attr->u.delay.la_rate;
+ } else {
+ rule->dl_delay_time = cfs_time_shift(cfs_rand() %
+ attr->u.delay.la_interval);
+ rule->dl_time_base = cfs_time_shift(attr->u.delay.la_interval);
+ }
+ spin_unlock(&rule->dl_lock);
+ }
+
+ lnet_net_unlock(cpt);
+}
+
int
lnet_fault_ctl(int opc, struct libcfs_ioctl_data *data)
{
return -EINVAL;
return lnet_drop_rule_list(data->ioc_count, attr, stat);
+
+ case LNET_CTL_DELAY_ADD:
+ if (!attr)
+ return -EINVAL;
+
+ return lnet_delay_rule_add(attr);
+
+ case LNET_CTL_DELAY_DEL:
+ if (!attr)
+ return -EINVAL;
+
+ data->ioc_count = lnet_delay_rule_del(attr->fa_src,
+ attr->fa_dst, false);
+ return 0;
+
+ case LNET_CTL_DELAY_RESET:
+ lnet_delay_rule_reset();
+ return 0;
+
+ case LNET_CTL_DELAY_LIST:
+ stat = (struct lnet_fault_stat *)data->ioc_inlbuf2;
+ if (!attr || !stat)
+ return -EINVAL;
+
+ return lnet_delay_rule_list(data->ioc_count, attr, stat);
}
}
CLASSERT(LNET_GET_BIT == 1 << LNET_MSG_GET);
CLASSERT(LNET_REPLY_BIT == 1 << LNET_MSG_REPLY);
+ mutex_init(&delay_dd.dd_mutex);
+ spin_lock_init(&delay_dd.dd_lock);
+ init_waitqueue_head(&delay_dd.dd_waitq);
+ init_waitqueue_head(&delay_dd.dd_ctl_waitq);
+ INIT_LIST_HEAD(&delay_dd.dd_sched_rules);
+
return 0;
}
lnet_fault_fini(void)
{
lnet_drop_rule_del(0, 0);
+ lnet_delay_rule_del(0, 0, true);
LASSERT(list_empty(&the_lnet.ln_drop_rules));
+ LASSERT(list_empty(&the_lnet.ln_delay_rules));
+ LASSERT(list_empty(&delay_dd.dd_sched_rules));
}
projects / karo-tx-linux.git / commitdiff