#include <linux/math64.h>
#include <linux/module.h>
#include <linux/spinlock.h>
+#include <linux/rcupdate.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>
u8 command;
};
+struct sched_gate_list {
+ struct rcu_head rcu;
+ struct list_head entries;
+ size_t num_entries;
+ s64 base_time;
+};
+
struct taprio_sched {
struct Qdisc **qdiscs;
struct Qdisc *root;
- s64 base_time;
int clockid;
atomic64_t picos_per_byte; /* Using picoseconds because for 10Gbps+
* speeds it's sub-nanoseconds per byte
*/
- size_t num_entries;
/* Protects the update side of the RCU protected current_entry */
spinlock_t current_entry_lock;
struct sched_entry __rcu *current_entry;
- struct list_head entries;
+ struct sched_gate_list __rcu *oper_sched;
+ struct sched_gate_list __rcu *admin_sched;
ktime_t (*get_time)(void);
struct hrtimer advance_timer;
struct list_head taprio_list;
};
+static ktime_t sched_base_time(const struct sched_gate_list *sched)
+{
+ if (!sched)
+ return KTIME_MAX;
+
+ return ns_to_ktime(sched->base_time);
+}
+
+static void taprio_free_sched_cb(struct rcu_head *head)
+{
+ struct sched_gate_list *sched = container_of(head, struct sched_gate_list, rcu);
+ struct sched_entry *entry, *n;
+
+ if (!sched)
+ return;
+
+ list_for_each_entry_safe(entry, n, &sched->entries, list) {
+ list_del(&entry->list);
+ kfree(entry);
+ }
+
+ kfree(sched);
+}
+
+static void switch_schedules(struct taprio_sched *q,
+ struct sched_gate_list **admin,
+ struct sched_gate_list **oper)
+{
+ rcu_assign_pointer(q->oper_sched, *admin);
+ rcu_assign_pointer(q->admin_sched, NULL);
+
+ if (*oper)
+ call_rcu(&(*oper)->rcu, taprio_free_sched_cb);
+
+ *oper = *admin;
+ *admin = NULL;
+}
+
static int taprio_enqueue(struct sk_buff *skb, struct Qdisc *sch,
struct sk_buff **to_free)
{
return skb;
}
+static bool should_change_schedules(const struct sched_gate_list *admin,
+ const struct sched_gate_list *oper,
+ ktime_t close_time)
+{
+ ktime_t next_base_time;
+
+ if (!admin)
+ return false;
+
+ next_base_time = sched_base_time(admin);
+
+ /* This is the simple case, the close_time would fall after
+ * the next schedule base_time.
+ */
+ if (ktime_compare(next_base_time, close_time) <= 0)
+ return true;
+
+ return false;
+}
+
static enum hrtimer_restart advance_sched(struct hrtimer *timer)
{
struct taprio_sched *q = container_of(timer, struct taprio_sched,
advance_timer);
+ struct sched_gate_list *oper, *admin;
struct sched_entry *entry, *next;
struct Qdisc *sch = q->root;
ktime_t close_time;
spin_lock(&q->current_entry_lock);
entry = rcu_dereference_protected(q->current_entry,
lockdep_is_held(&q->current_entry_lock));
+ oper = rcu_dereference_protected(q->oper_sched,
+ lockdep_is_held(&q->current_entry_lock));
+ admin = rcu_dereference_protected(q->admin_sched,
+ lockdep_is_held(&q->current_entry_lock));
- /* This is the case that it's the first time that the schedule
- * runs, so it only happens once per schedule. The first entry
- * is pre-calculated during the schedule initialization.
+ if (!oper)
+ switch_schedules(q, &admin, &oper);
+
+ /* This can happen in two cases: 1. this is the very first run
+ * of this function (i.e. we weren't running any schedule
+ * previously); 2. The previous schedule just ended. The first
+ * entry of all schedules are pre-calculated during the
+ * schedule initialization.
*/
- if (unlikely(!entry)) {
- next = list_first_entry(&q->entries, struct sched_entry,
+ if (unlikely(!entry || entry->close_time == oper->base_time)) {
+ next = list_first_entry(&oper->entries, struct sched_entry,
list);
close_time = next->close_time;
goto first_run;
}
- if (list_is_last(&entry->list, &q->entries))
- next = list_first_entry(&q->entries, struct sched_entry,
+ if (list_is_last(&entry->list, &oper->entries))
+ next = list_first_entry(&oper->entries, struct sched_entry,
list);
else
next = list_next_entry(entry, list);
close_time = ktime_add_ns(entry->close_time, next->interval);
+ if (should_change_schedules(admin, oper, close_time)) {
+ /* Set things so the next time this runs, the new
+ * schedule runs.
+ */
+ close_time = sched_base_time(admin);
+ switch_schedules(q, &admin, &oper);
+ }
+
next->close_time = close_time;
taprio_set_budget(q, next);
return fill_sched_entry(tb, entry, extack);
}
-/* Returns the number of entries in case of success */
-static int parse_sched_single_entry(struct nlattr *n,
- struct taprio_sched *q,
- struct netlink_ext_ack *extack)
-{
- struct nlattr *tb_entry[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = { };
- struct nlattr *tb_list[TCA_TAPRIO_SCHED_MAX + 1] = { };
- struct sched_entry *entry;
- bool found = false;
- u32 index;
- int err;
-
- err = nla_parse_nested_deprecated(tb_list, TCA_TAPRIO_SCHED_MAX, n,
- entry_list_policy, NULL);
- if (err < 0) {
- NL_SET_ERR_MSG(extack, "Could not parse nested entry");
- return -EINVAL;
- }
-
- if (!tb_list[TCA_TAPRIO_SCHED_ENTRY]) {
- NL_SET_ERR_MSG(extack, "Single-entry must include an entry");
- return -EINVAL;
- }
-
- err = nla_parse_nested_deprecated(tb_entry,
- TCA_TAPRIO_SCHED_ENTRY_MAX,
- tb_list[TCA_TAPRIO_SCHED_ENTRY],
- entry_policy, NULL);
- if (err < 0) {
- NL_SET_ERR_MSG(extack, "Could not parse nested entry");
- return -EINVAL;
- }
-
- if (!tb_entry[TCA_TAPRIO_SCHED_ENTRY_INDEX]) {
- NL_SET_ERR_MSG(extack, "Entry must specify an index\n");
- return -EINVAL;
- }
-
- index = nla_get_u32(tb_entry[TCA_TAPRIO_SCHED_ENTRY_INDEX]);
- if (index >= q->num_entries) {
- NL_SET_ERR_MSG(extack, "Index for single entry exceeds number of entries in schedule");
- return -EINVAL;
- }
-
- list_for_each_entry(entry, &q->entries, list) {
- if (entry->index == index) {
- found = true;
- break;
- }
- }
-
- if (!found) {
- NL_SET_ERR_MSG(extack, "Could not find entry");
- return -ENOENT;
- }
-
- err = fill_sched_entry(tb_entry, entry, extack);
- if (err < 0)
- return err;
-
- return q->num_entries;
-}
-
static int parse_sched_list(struct nlattr *list,
- struct taprio_sched *q,
+ struct sched_gate_list *sched,
struct netlink_ext_ack *extack)
{
struct nlattr *n;
return err;
}
- list_add_tail(&entry->list, &q->entries);
+ list_add_tail(&entry->list, &sched->entries);
i++;
}
- q->num_entries = i;
+ sched->num_entries = i;
return i;
}
-/* Returns the number of entries in case of success */
-static int parse_taprio_opt(struct nlattr **tb, struct taprio_sched *q,
- struct netlink_ext_ack *extack)
+static int parse_taprio_schedule(struct nlattr **tb,
+ struct sched_gate_list *new,
+ struct netlink_ext_ack *extack)
{
int err = 0;
- int clockid;
-
- if (tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST] &&
- tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY])
- return -EINVAL;
- if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY] && q->num_entries == 0)
- return -EINVAL;
-
- if (q->clockid == -1 && !tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID])
- return -EINVAL;
+ if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY]) {
+ NL_SET_ERR_MSG(extack, "Adding a single entry is not supported");
+ return -ENOTSUPP;
+ }
if (tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME])
- q->base_time = nla_get_s64(
- tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]);
-
- if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) {
- clockid = nla_get_s32(tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]);
-
- /* We only support static clockids and we don't allow
- * for it to be modified after the first init.
- */
- if (clockid < 0 || (q->clockid != -1 && q->clockid != clockid))
- return -EINVAL;
-
- q->clockid = clockid;
- }
+ new->base_time = nla_get_s64(tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]);
if (tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST])
err = parse_sched_list(
- tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST], q, extack);
- else if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY])
- err = parse_sched_single_entry(
- tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY], q, extack);
-
- /* parse_sched_* return the number of entries in the schedule,
- * a schedule with zero entries is an error.
- */
- if (err == 0) {
- NL_SET_ERR_MSG(extack, "The schedule should contain at least one entry");
- return -EINVAL;
- }
+ tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST], new, extack);
+ if (err < 0)
+ return err;
- return err;
+ return 0;
}
static int taprio_parse_mqprio_opt(struct net_device *dev,
{
int i, j;
- if (!qopt) {
+ if (!qopt && !dev->num_tc) {
NL_SET_ERR_MSG(extack, "'mqprio' configuration is necessary");
return -EINVAL;
}
+ /* If num_tc is already set, it means that the user already
+ * configured the mqprio part
+ */
+ if (dev->num_tc)
+ return 0;
+
/* Verify num_tc is not out of max range */
if (qopt->num_tc > TC_MAX_QUEUE) {
NL_SET_ERR_MSG(extack, "Number of traffic classes is outside valid range");
return 0;
}
-static int taprio_get_start_time(struct Qdisc *sch, ktime_t *start)
+static int taprio_get_start_time(struct Qdisc *sch,
+ struct sched_gate_list *sched,
+ ktime_t *start)
{
struct taprio_sched *q = qdisc_priv(sch);
struct sched_entry *entry;
ktime_t now, base, cycle;
s64 n;
- base = ns_to_ktime(q->base_time);
+ base = sched_base_time(sched);
now = q->get_time();
if (ktime_after(base, now)) {
/* Calculate the cycle_time, by summing all the intervals.
*/
cycle = 0;
- list_for_each_entry(entry, &q->entries, list)
+ list_for_each_entry(entry, &sched->entries, list)
cycle = ktime_add_ns(cycle, entry->interval);
/* The qdisc is expected to have at least one sched_entry. Moreover,
return 0;
}
-static void taprio_start_sched(struct Qdisc *sch, ktime_t start)
+static void setup_first_close_time(struct taprio_sched *q,
+ struct sched_gate_list *sched, ktime_t base)
{
- struct taprio_sched *q = qdisc_priv(sch);
struct sched_entry *first;
- unsigned long flags;
-
- spin_lock_irqsave(&q->current_entry_lock, flags);
- first = list_first_entry(&q->entries, struct sched_entry,
- list);
+ first = list_first_entry(&sched->entries,
+ struct sched_entry, list);
- first->close_time = ktime_add_ns(start, first->interval);
+ first->close_time = ktime_add_ns(base, first->interval);
taprio_set_budget(q, first);
rcu_assign_pointer(q->current_entry, NULL);
+}
- spin_unlock_irqrestore(&q->current_entry_lock, flags);
+static void taprio_start_sched(struct Qdisc *sch,
+ ktime_t start, struct sched_gate_list *new)
+{
+ struct taprio_sched *q = qdisc_priv(sch);
+ ktime_t expires;
+
+ expires = hrtimer_get_expires(&q->advance_timer);
+ if (expires == 0)
+ expires = KTIME_MAX;
+
+ /* If the new schedule starts before the next expiration, we
+ * reprogram it to the earliest one, so we change the admin
+ * schedule to the operational one at the right time.
+ */
+ start = min_t(ktime_t, start, expires);
hrtimer_start(&q->advance_timer, start, HRTIMER_MODE_ABS);
}
struct netlink_ext_ack *extack)
{
struct nlattr *tb[TCA_TAPRIO_ATTR_MAX + 1] = { };
+ struct sched_gate_list *oper, *admin, *new_admin;
struct taprio_sched *q = qdisc_priv(sch);
struct net_device *dev = qdisc_dev(sch);
struct tc_mqprio_qopt *mqprio = NULL;
- int i, err, size;
+ int i, err, clockid;
+ unsigned long flags;
ktime_t start;
err = nla_parse_nested_deprecated(tb, TCA_TAPRIO_ATTR_MAX, opt,
if (err < 0)
return err;
- /* A schedule with less than one entry is an error */
- size = parse_taprio_opt(tb, q, extack);
- if (size < 0)
- return size;
+ new_admin = kzalloc(sizeof(*new_admin), GFP_KERNEL);
+ if (!new_admin) {
+ NL_SET_ERR_MSG(extack, "Not enough memory for a new schedule");
+ return -ENOMEM;
+ }
+ INIT_LIST_HEAD(&new_admin->entries);
- hrtimer_init(&q->advance_timer, q->clockid, HRTIMER_MODE_ABS);
- q->advance_timer.function = advance_sched;
+ rcu_read_lock();
+ oper = rcu_dereference(q->oper_sched);
+ admin = rcu_dereference(q->admin_sched);
+ rcu_read_unlock();
- switch (q->clockid) {
- case CLOCK_REALTIME:
- q->get_time = ktime_get_real;
- break;
- case CLOCK_MONOTONIC:
- q->get_time = ktime_get;
- break;
- case CLOCK_BOOTTIME:
- q->get_time = ktime_get_boottime;
- break;
- case CLOCK_TAI:
- q->get_time = ktime_get_clocktai;
- break;
- default:
- return -ENOTSUPP;
+ if (mqprio && (oper || admin)) {
+ NL_SET_ERR_MSG(extack, "Changing the traffic mapping of a running schedule is not supported");
+ err = -ENOTSUPP;
+ goto free_sched;
}
- for (i = 0; i < dev->num_tx_queues; i++) {
- struct netdev_queue *dev_queue;
- struct Qdisc *qdisc;
+ err = parse_taprio_schedule(tb, new_admin, extack);
+ if (err < 0)
+ goto free_sched;
- dev_queue = netdev_get_tx_queue(dev, i);
- qdisc = qdisc_create_dflt(dev_queue,
- &pfifo_qdisc_ops,
- TC_H_MAKE(TC_H_MAJ(sch->handle),
- TC_H_MIN(i + 1)),
- extack);
- if (!qdisc)
- return -ENOMEM;
+ if (new_admin->num_entries == 0) {
+ NL_SET_ERR_MSG(extack, "There should be at least one entry in the schedule");
+ err = -EINVAL;
+ goto free_sched;
+ }
- if (i < dev->real_num_tx_queues)
- qdisc_hash_add(qdisc, false);
+ if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) {
+ clockid = nla_get_s32(tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]);
- q->qdiscs[i] = qdisc;
+ /* We only support static clockids and we don't allow
+ * for it to be modified after the first init.
+ */
+ if (clockid < 0 ||
+ (q->clockid != -1 && q->clockid != clockid)) {
+ NL_SET_ERR_MSG(extack, "Changing the 'clockid' of a running schedule is not supported");
+ err = -ENOTSUPP;
+ goto free_sched;
+ }
+
+ q->clockid = clockid;
+ }
+
+ if (q->clockid == -1 && !tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) {
+ NL_SET_ERR_MSG(extack, "Specifying a 'clockid' is mandatory");
+ err = -EINVAL;
+ goto free_sched;
+ }
+
+ taprio_set_picos_per_byte(dev, q);
+
+ /* Protects against enqueue()/dequeue() */
+ spin_lock_bh(qdisc_lock(sch));
+
+ if (!hrtimer_active(&q->advance_timer)) {
+ hrtimer_init(&q->advance_timer, q->clockid, HRTIMER_MODE_ABS);
+ q->advance_timer.function = advance_sched;
}
if (mqprio) {
mqprio->prio_tc_map[i]);
}
- taprio_set_picos_per_byte(dev, q);
+ switch (q->clockid) {
+ case CLOCK_REALTIME:
+ q->get_time = ktime_get_real;
+ break;
+ case CLOCK_MONOTONIC:
+ q->get_time = ktime_get;
+ break;
+ case CLOCK_BOOTTIME:
+ q->get_time = ktime_get_boottime;
+ break;
+ case CLOCK_TAI:
+ q->get_time = ktime_get_clocktai;
+ break;
+ default:
+ NL_SET_ERR_MSG(extack, "Invalid 'clockid'");
+ err = -EINVAL;
+ goto unlock;
+ }
- err = taprio_get_start_time(sch, &start);
+ err = taprio_get_start_time(sch, new_admin, &start);
if (err < 0) {
NL_SET_ERR_MSG(extack, "Internal error: failed get start time");
- return err;
+ goto unlock;
}
- taprio_start_sched(sch, start);
+ setup_first_close_time(q, new_admin, start);
- return 0;
+ /* Protects against advance_sched() */
+ spin_lock_irqsave(&q->current_entry_lock, flags);
+
+ taprio_start_sched(sch, start, new_admin);
+
+ rcu_assign_pointer(q->admin_sched, new_admin);
+ if (admin)
+ call_rcu(&admin->rcu, taprio_free_sched_cb);
+ new_admin = NULL;
+
+ spin_unlock_irqrestore(&q->current_entry_lock, flags);
+
+ err = 0;
+
+unlock:
+ spin_unlock_bh(qdisc_lock(sch));
+
+free_sched:
+ kfree(new_admin);
+
+ return err;
}
static void taprio_destroy(struct Qdisc *sch)
{
struct taprio_sched *q = qdisc_priv(sch);
struct net_device *dev = qdisc_dev(sch);
- struct sched_entry *entry, *n;
unsigned int i;
spin_lock(&taprio_list_lock);
netdev_set_num_tc(dev, 0);
- list_for_each_entry_safe(entry, n, &q->entries, list) {
- list_del(&entry->list);
- kfree(entry);
- }
+ if (q->oper_sched)
+ call_rcu(&q->oper_sched->rcu, taprio_free_sched_cb);
+
+ if (q->admin_sched)
+ call_rcu(&q->admin_sched->rcu, taprio_free_sched_cb);
}
static int taprio_init(struct Qdisc *sch, struct nlattr *opt,
{
struct taprio_sched *q = qdisc_priv(sch);
struct net_device *dev = qdisc_dev(sch);
+ int i;
- INIT_LIST_HEAD(&q->entries);
spin_lock_init(&q->current_entry_lock);
- /* We may overwrite the configuration later */
hrtimer_init(&q->advance_timer, CLOCK_TAI, HRTIMER_MODE_ABS);
+ q->advance_timer.function = advance_sched;
q->root = sch;
list_add(&q->taprio_list, &taprio_list);
spin_unlock(&taprio_list_lock);
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ struct netdev_queue *dev_queue;
+ struct Qdisc *qdisc;
+
+ dev_queue = netdev_get_tx_queue(dev, i);
+ qdisc = qdisc_create_dflt(dev_queue,
+ &pfifo_qdisc_ops,
+ TC_H_MAKE(TC_H_MAJ(sch->handle),
+ TC_H_MIN(i + 1)),
+ extack);
+ if (!qdisc)
+ return -ENOMEM;
+
+ if (i < dev->real_num_tx_queues)
+ qdisc_hash_add(qdisc, false);
+
+ q->qdiscs[i] = qdisc;
+ }
+
return taprio_change(sch, opt, extack);
}
return -1;
}
+static int dump_schedule(struct sk_buff *msg,
+ const struct sched_gate_list *root)
+{
+ struct nlattr *entry_list;
+ struct sched_entry *entry;
+
+ if (nla_put_s64(msg, TCA_TAPRIO_ATTR_SCHED_BASE_TIME,
+ root->base_time, TCA_TAPRIO_PAD))
+ return -1;
+
+ entry_list = nla_nest_start_noflag(msg,
+ TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST);
+ if (!entry_list)
+ goto error_nest;
+
+ list_for_each_entry(entry, &root->entries, list) {
+ if (dump_entry(msg, entry) < 0)
+ goto error_nest;
+ }
+
+ nla_nest_end(msg, entry_list);
+ return 0;
+
+error_nest:
+ nla_nest_cancel(msg, entry_list);
+ return -1;
+}
+
static int taprio_dump(struct Qdisc *sch, struct sk_buff *skb)
{
struct taprio_sched *q = qdisc_priv(sch);
struct net_device *dev = qdisc_dev(sch);
+ struct sched_gate_list *oper, *admin;
struct tc_mqprio_qopt opt = { 0 };
- struct nlattr *nest, *entry_list;
- struct sched_entry *entry;
+ struct nlattr *nest, *sched_nest;
unsigned int i;
+ rcu_read_lock();
+ oper = rcu_dereference(q->oper_sched);
+ admin = rcu_dereference(q->admin_sched);
+
opt.num_tc = netdev_get_num_tc(dev);
memcpy(opt.prio_tc_map, dev->prio_tc_map, sizeof(opt.prio_tc_map));
nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
if (!nest)
- return -ENOSPC;
+ goto start_error;
if (nla_put(skb, TCA_TAPRIO_ATTR_PRIOMAP, sizeof(opt), &opt))
goto options_error;
- if (nla_put_s64(skb, TCA_TAPRIO_ATTR_SCHED_BASE_TIME,
- q->base_time, TCA_TAPRIO_PAD))
- goto options_error;
-
if (nla_put_s32(skb, TCA_TAPRIO_ATTR_SCHED_CLOCKID, q->clockid))
goto options_error;
- entry_list = nla_nest_start_noflag(skb,
- TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST);
- if (!entry_list)
+ if (oper && dump_schedule(skb, oper))
goto options_error;
- list_for_each_entry(entry, &q->entries, list) {
- if (dump_entry(skb, entry) < 0)
- goto options_error;
- }
+ if (!admin)
+ goto done;
+
+ sched_nest = nla_nest_start_noflag(skb, TCA_TAPRIO_ATTR_ADMIN_SCHED);
- nla_nest_end(skb, entry_list);
+ if (dump_schedule(skb, admin))
+ goto admin_error;
+
+ nla_nest_end(skb, sched_nest);
+
+done:
+ rcu_read_unlock();
return nla_nest_end(skb, nest);
+admin_error:
+ nla_nest_cancel(skb, sched_nest);
+
options_error:
nla_nest_cancel(skb, nest);
- return -1;
+
+start_error:
+ rcu_read_unlock();
+ return -ENOSPC;
}
static struct Qdisc *taprio_leaf(struct Qdisc *sch, unsigned long cl)
.id = "taprio",
.priv_size = sizeof(struct taprio_sched),
.init = taprio_init,
+ .change = taprio_change,
.destroy = taprio_destroy,
.peek = taprio_peek,
.dequeue = taprio_dequeue,
projects / users / hch / configfs.git / commitdiff