Commit f8d62037 authored by Edward Cree's avatar Edward Cree Committed by David S. Miller

sfc: ARFS filter IDs

Associate an arbitrary ID with each ARFS filter, allowing to properly query
 for expiry.  The association is maintained in a hash table, which is
 protected by a spinlock.

v3: fix build warnings when CONFIG_RFS_ACCEL is disabled (thanks lkp-robot).
v2: fixed uninitialised variable (thanks davem and lkp-robot).

Fixes: 3af0f342 ("sfc: replace asynchronous filter operations")
Signed-off-by: default avatarEdward Cree <ecree@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d805c520
......@@ -3999,29 +3999,6 @@ static void efx_ef10_prepare_flr(struct efx_nic *efx)
atomic_set(&efx->active_queues, 0);
}
static bool efx_ef10_filter_equal(const struct efx_filter_spec *left,
const struct efx_filter_spec *right)
{
if ((left->match_flags ^ right->match_flags) |
((left->flags ^ right->flags) &
(EFX_FILTER_FLAG_RX | EFX_FILTER_FLAG_TX)))
return false;
return memcmp(&left->outer_vid, &right->outer_vid,
sizeof(struct efx_filter_spec) -
offsetof(struct efx_filter_spec, outer_vid)) == 0;
}
static unsigned int efx_ef10_filter_hash(const struct efx_filter_spec *spec)
{
BUILD_BUG_ON(offsetof(struct efx_filter_spec, outer_vid) & 3);
return jhash2((const u32 *)&spec->outer_vid,
(sizeof(struct efx_filter_spec) -
offsetof(struct efx_filter_spec, outer_vid)) / 4,
0);
/* XXX should we randomise the initval? */
}
/* Decide whether a filter should be exclusive or else should allow
* delivery to additional recipients. Currently we decide that
* filters for specific local unicast MAC and IP addresses are
......@@ -4346,7 +4323,7 @@ static s32 efx_ef10_filter_insert(struct efx_nic *efx,
goto out_unlock;
match_pri = rc;
hash = efx_ef10_filter_hash(spec);
hash = efx_filter_spec_hash(spec);
is_mc_recip = efx_filter_is_mc_recipient(spec);
if (is_mc_recip)
bitmap_zero(mc_rem_map, EFX_EF10_FILTER_SEARCH_LIMIT);
......@@ -4378,7 +4355,7 @@ static s32 efx_ef10_filter_insert(struct efx_nic *efx,
if (!saved_spec) {
if (ins_index < 0)
ins_index = i;
} else if (efx_ef10_filter_equal(spec, saved_spec)) {
} else if (efx_filter_spec_equal(spec, saved_spec)) {
if (spec->priority < saved_spec->priority &&
spec->priority != EFX_FILTER_PRI_AUTO) {
rc = -EPERM;
......@@ -4762,27 +4739,62 @@ static s32 efx_ef10_filter_get_rx_ids(struct efx_nic *efx,
static bool efx_ef10_filter_rfs_expire_one(struct efx_nic *efx, u32 flow_id,
unsigned int filter_idx)
{
struct efx_filter_spec *spec, saved_spec;
struct efx_ef10_filter_table *table;
struct efx_filter_spec *spec;
bool ret;
struct efx_arfs_rule *rule = NULL;
bool ret = true, force = false;
u16 arfs_id;
down_read(&efx->filter_sem);
table = efx->filter_state;
down_write(&table->lock);
spec = efx_ef10_filter_entry_spec(table, filter_idx);
if (!spec || spec->priority != EFX_FILTER_PRI_HINT) {
ret = true;
if (!spec || spec->priority != EFX_FILTER_PRI_HINT)
goto out_unlock;
}
if (!rps_may_expire_flow(efx->net_dev, spec->dmaq_id, flow_id, 0)) {
ret = false;
goto out_unlock;
spin_lock_bh(&efx->rps_hash_lock);
if (!efx->rps_hash_table) {
/* In the absence of the table, we always return 0 to ARFS. */
arfs_id = 0;
} else {
rule = efx_rps_hash_find(efx, spec);
if (!rule)
/* ARFS table doesn't know of this filter, so remove it */
goto expire;
arfs_id = rule->arfs_id;
ret = efx_rps_check_rule(rule, filter_idx, &force);
if (force)
goto expire;
if (!ret) {
spin_unlock_bh(&efx->rps_hash_lock);
goto out_unlock;
}
}
if (!rps_may_expire_flow(efx->net_dev, spec->dmaq_id, flow_id, arfs_id))
ret = false;
else if (rule)
rule->filter_id = EFX_ARFS_FILTER_ID_REMOVING;
expire:
saved_spec = *spec; /* remove operation will kfree spec */
spin_unlock_bh(&efx->rps_hash_lock);
/* At this point (since we dropped the lock), another thread might queue
* up a fresh insertion request (but the actual insertion will be held
* up by our possession of the filter table lock). In that case, it
* will set rule->filter_id to EFX_ARFS_FILTER_ID_PENDING, meaning that
* the rule is not removed by efx_rps_hash_del() below.
*/
ret = efx_ef10_filter_remove_internal(efx, 1U << spec->priority,
filter_idx, true) == 0;
/* While we can't safely dereference rule (we dropped the lock), we can
* still test it for NULL.
*/
if (ret && rule) {
/* Expiring, so remove entry from ARFS table */
spin_lock_bh(&efx->rps_hash_lock);
efx_rps_hash_del(efx, &saved_spec);
spin_unlock_bh(&efx->rps_hash_lock);
}
out_unlock:
up_write(&table->lock);
up_read(&efx->filter_sem);
......
......@@ -3027,6 +3027,10 @@ static int efx_init_struct(struct efx_nic *efx,
mutex_init(&efx->mac_lock);
#ifdef CONFIG_RFS_ACCEL
mutex_init(&efx->rps_mutex);
spin_lock_init(&efx->rps_hash_lock);
/* Failure to allocate is not fatal, but may degrade ARFS performance */
efx->rps_hash_table = kcalloc(EFX_ARFS_HASH_TABLE_SIZE,
sizeof(*efx->rps_hash_table), GFP_KERNEL);
#endif
efx->phy_op = &efx_dummy_phy_operations;
efx->mdio.dev = net_dev;
......@@ -3070,6 +3074,10 @@ static void efx_fini_struct(struct efx_nic *efx)
{
int i;
#ifdef CONFIG_RFS_ACCEL
kfree(efx->rps_hash_table);
#endif
for (i = 0; i < EFX_MAX_CHANNELS; i++)
kfree(efx->channel[i]);
......@@ -3092,6 +3100,141 @@ void efx_update_sw_stats(struct efx_nic *efx, u64 *stats)
stats[GENERIC_STAT_rx_noskb_drops] = atomic_read(&efx->n_rx_noskb_drops);
}
bool efx_filter_spec_equal(const struct efx_filter_spec *left,
const struct efx_filter_spec *right)
{
if ((left->match_flags ^ right->match_flags) |
((left->flags ^ right->flags) &
(EFX_FILTER_FLAG_RX | EFX_FILTER_FLAG_TX)))
return false;
return memcmp(&left->outer_vid, &right->outer_vid,
sizeof(struct efx_filter_spec) -
offsetof(struct efx_filter_spec, outer_vid)) == 0;
}
u32 efx_filter_spec_hash(const struct efx_filter_spec *spec)
{
BUILD_BUG_ON(offsetof(struct efx_filter_spec, outer_vid) & 3);
return jhash2((const u32 *)&spec->outer_vid,
(sizeof(struct efx_filter_spec) -
offsetof(struct efx_filter_spec, outer_vid)) / 4,
0);
}
#ifdef CONFIG_RFS_ACCEL
bool efx_rps_check_rule(struct efx_arfs_rule *rule, unsigned int filter_idx,
bool *force)
{
if (rule->filter_id == EFX_ARFS_FILTER_ID_PENDING) {
/* ARFS is currently updating this entry, leave it */
return false;
}
if (rule->filter_id == EFX_ARFS_FILTER_ID_ERROR) {
/* ARFS tried and failed to update this, so it's probably out
* of date. Remove the filter and the ARFS rule entry.
*/
rule->filter_id = EFX_ARFS_FILTER_ID_REMOVING;
*force = true;
return true;
} else if (WARN_ON(rule->filter_id != filter_idx)) { /* can't happen */
/* ARFS has moved on, so old filter is not needed. Since we did
* not mark the rule with EFX_ARFS_FILTER_ID_REMOVING, it will
* not be removed by efx_rps_hash_del() subsequently.
*/
*force = true;
return true;
}
/* Remove it iff ARFS wants to. */
return true;
}
struct hlist_head *efx_rps_hash_bucket(struct efx_nic *efx,
const struct efx_filter_spec *spec)
{
u32 hash = efx_filter_spec_hash(spec);
WARN_ON(!spin_is_locked(&efx->rps_hash_lock));
if (!efx->rps_hash_table)
return NULL;
return &efx->rps_hash_table[hash % EFX_ARFS_HASH_TABLE_SIZE];
}
struct efx_arfs_rule *efx_rps_hash_find(struct efx_nic *efx,
const struct efx_filter_spec *spec)
{
struct efx_arfs_rule *rule;
struct hlist_head *head;
struct hlist_node *node;
head = efx_rps_hash_bucket(efx, spec);
if (!head)
return NULL;
hlist_for_each(node, head) {
rule = container_of(node, struct efx_arfs_rule, node);
if (efx_filter_spec_equal(spec, &rule->spec))
return rule;
}
return NULL;
}
struct efx_arfs_rule *efx_rps_hash_add(struct efx_nic *efx,
const struct efx_filter_spec *spec,
bool *new)
{
struct efx_arfs_rule *rule;
struct hlist_head *head;
struct hlist_node *node;
head = efx_rps_hash_bucket(efx, spec);
if (!head)
return NULL;
hlist_for_each(node, head) {
rule = container_of(node, struct efx_arfs_rule, node);
if (efx_filter_spec_equal(spec, &rule->spec)) {
*new = false;
return rule;
}
}
rule = kmalloc(sizeof(*rule), GFP_ATOMIC);
*new = true;
if (rule) {
memcpy(&rule->spec, spec, sizeof(rule->spec));
hlist_add_head(&rule->node, head);
}
return rule;
}
void efx_rps_hash_del(struct efx_nic *efx, const struct efx_filter_spec *spec)
{
struct efx_arfs_rule *rule;
struct hlist_head *head;
struct hlist_node *node;
head = efx_rps_hash_bucket(efx, spec);
if (WARN_ON(!head))
return;
hlist_for_each(node, head) {
rule = container_of(node, struct efx_arfs_rule, node);
if (efx_filter_spec_equal(spec, &rule->spec)) {
/* Someone already reused the entry. We know that if
* this check doesn't fire (i.e. filter_id == REMOVING)
* then the REMOVING mark was put there by our caller,
* because caller is holding a lock on filter table and
* only holders of that lock set REMOVING.
*/
if (rule->filter_id != EFX_ARFS_FILTER_ID_REMOVING)
return;
hlist_del(node);
kfree(rule);
return;
}
}
/* We didn't find it. */
WARN_ON(1);
}
#endif
/* RSS contexts. We're using linked lists and crappy O(n) algorithms, because
* (a) this is an infrequent control-plane operation and (b) n is small (max 64)
*/
......
......@@ -186,6 +186,27 @@ static inline void efx_filter_rfs_expire(struct work_struct *data) {}
#endif
bool efx_filter_is_mc_recipient(const struct efx_filter_spec *spec);
bool efx_filter_spec_equal(const struct efx_filter_spec *left,
const struct efx_filter_spec *right);
u32 efx_filter_spec_hash(const struct efx_filter_spec *spec);
#ifdef CONFIG_RFS_ACCEL
bool efx_rps_check_rule(struct efx_arfs_rule *rule, unsigned int filter_idx,
bool *force);
struct efx_arfs_rule *efx_rps_hash_find(struct efx_nic *efx,
const struct efx_filter_spec *spec);
/* @new is written to indicate if entry was newly added (true) or if an old
* entry was found and returned (false).
*/
struct efx_arfs_rule *efx_rps_hash_add(struct efx_nic *efx,
const struct efx_filter_spec *spec,
bool *new);
void efx_rps_hash_del(struct efx_nic *efx, const struct efx_filter_spec *spec);
#endif
/* RSS contexts */
struct efx_rss_context *efx_alloc_rss_context_entry(struct efx_nic *efx);
struct efx_rss_context *efx_find_rss_context_entry(struct efx_nic *efx, u32 id);
......
......@@ -2905,18 +2905,45 @@ bool efx_farch_filter_rfs_expire_one(struct efx_nic *efx, u32 flow_id,
{
struct efx_farch_filter_state *state = efx->filter_state;
struct efx_farch_filter_table *table;
bool ret = false;
bool ret = false, force = false;
u16 arfs_id;
down_write(&state->lock);
spin_lock_bh(&efx->rps_hash_lock);
table = &state->table[EFX_FARCH_FILTER_TABLE_RX_IP];
if (test_bit(index, table->used_bitmap) &&
table->spec[index].priority == EFX_FILTER_PRI_HINT &&
rps_may_expire_flow(efx->net_dev, table->spec[index].dmaq_id,
flow_id, 0)) {
efx_farch_filter_table_clear_entry(efx, table, index);
ret = true;
table->spec[index].priority == EFX_FILTER_PRI_HINT) {
struct efx_arfs_rule *rule = NULL;
struct efx_filter_spec spec;
efx_farch_filter_to_gen_spec(&spec, &table->spec[index]);
if (!efx->rps_hash_table) {
/* In the absence of the table, we always returned 0 to
* ARFS, so use the same to query it.
*/
arfs_id = 0;
} else {
rule = efx_rps_hash_find(efx, &spec);
if (!rule) {
/* ARFS table doesn't know of this filter, remove it */
force = true;
} else {
arfs_id = rule->arfs_id;
if (!efx_rps_check_rule(rule, index, &force))
goto out_unlock;
}
}
if (force || rps_may_expire_flow(efx->net_dev, spec.dmaq_id,
flow_id, arfs_id)) {
if (rule)
rule->filter_id = EFX_ARFS_FILTER_ID_REMOVING;
efx_rps_hash_del(efx, &spec);
efx_farch_filter_table_clear_entry(efx, table, index);
ret = true;
}
}
out_unlock:
spin_unlock_bh(&efx->rps_hash_lock);
up_write(&state->lock);
return ret;
}
......
......@@ -734,6 +734,35 @@ struct efx_rss_context {
};
#ifdef CONFIG_RFS_ACCEL
/* Order of these is important, since filter_id >= %EFX_ARFS_FILTER_ID_PENDING
* is used to test if filter does or will exist.
*/
#define EFX_ARFS_FILTER_ID_PENDING -1
#define EFX_ARFS_FILTER_ID_ERROR -2
#define EFX_ARFS_FILTER_ID_REMOVING -3
/**
* struct efx_arfs_rule - record of an ARFS filter and its IDs
* @node: linkage into hash table
* @spec: details of the filter (used as key for hash table). Use efx->type to
* determine which member to use.
* @rxq_index: channel to which the filter will steer traffic.
* @arfs_id: filter ID which was returned to ARFS
* @filter_id: index in software filter table. May be
* %EFX_ARFS_FILTER_ID_PENDING if filter was not inserted yet,
* %EFX_ARFS_FILTER_ID_ERROR if filter insertion failed, or
* %EFX_ARFS_FILTER_ID_REMOVING if expiry is currently removing the filter.
*/
struct efx_arfs_rule {
struct hlist_node node;
struct efx_filter_spec spec;
u16 rxq_index;
u16 arfs_id;
s32 filter_id;
};
/* Size chosen so that the table is one page (4kB) */
#define EFX_ARFS_HASH_TABLE_SIZE 512
/**
* struct efx_async_filter_insertion - Request to asynchronously insert a filter
* @net_dev: Reference to the netdevice
......@@ -873,6 +902,10 @@ struct efx_async_filter_insertion {
* @rps_expire_channel's @rps_flow_id
* @rps_slot_map: bitmap of in-flight entries in @rps_slot
* @rps_slot: array of ARFS insertion requests for efx_filter_rfs_work()
* @rps_hash_lock: Protects ARFS filter mapping state (@rps_hash_table and
* @rps_next_id).
* @rps_hash_table: Mapping between ARFS filters and their various IDs
* @rps_next_id: next arfs_id for an ARFS filter
* @active_queues: Count of RX and TX queues that haven't been flushed and drained.
* @rxq_flush_pending: Count of number of receive queues that need to be flushed.
* Decremented when the efx_flush_rx_queue() is called.
......@@ -1029,6 +1062,9 @@ struct efx_nic {
unsigned int rps_expire_index;
unsigned long rps_slot_map;
struct efx_async_filter_insertion rps_slot[EFX_RPS_MAX_IN_FLIGHT];
spinlock_t rps_hash_lock;
struct hlist_head *rps_hash_table;
u32 rps_next_id;
#endif
atomic_t active_queues;
......
......@@ -834,9 +834,29 @@ static void efx_filter_rfs_work(struct work_struct *data)
struct efx_nic *efx = netdev_priv(req->net_dev);
struct efx_channel *channel = efx_get_channel(efx, req->rxq_index);
int slot_idx = req - efx->rps_slot;
struct efx_arfs_rule *rule;
u16 arfs_id = 0;
int rc;
rc = efx->type->filter_insert(efx, &req->spec, true);
if (efx->rps_hash_table) {
spin_lock_bh(&efx->rps_hash_lock);
rule = efx_rps_hash_find(efx, &req->spec);
/* The rule might have already gone, if someone else's request
* for the same spec was already worked and then expired before
* we got around to our work. In that case we have nothing
* tying us to an arfs_id, meaning that as soon as the filter
* is considered for expiry it will be removed.
*/
if (rule) {
if (rc < 0)
rule->filter_id = EFX_ARFS_FILTER_ID_ERROR;
else
rule->filter_id = rc;
arfs_id = rule->arfs_id;
}
spin_unlock_bh(&efx->rps_hash_lock);
}
if (rc >= 0) {
/* Remember this so we can check whether to expire the filter
* later.
......@@ -848,18 +868,18 @@ static void efx_filter_rfs_work(struct work_struct *data)
if (req->spec.ether_type == htons(ETH_P_IP))
netif_info(efx, rx_status, efx->net_dev,
"steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n",
"steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d id %u]\n",
(req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
req->spec.rem_host, ntohs(req->spec.rem_port),
req->spec.loc_host, ntohs(req->spec.loc_port),
req->rxq_index, req->flow_id, rc);
req->rxq_index, req->flow_id, rc, arfs_id);
else
netif_info(efx, rx_status, efx->net_dev,
"steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d]\n",
"steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d id %u]\n",
(req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
req->spec.rem_host, ntohs(req->spec.rem_port),
req->spec.loc_host, ntohs(req->spec.loc_port),
req->rxq_index, req->flow_id, rc);
req->rxq_index, req->flow_id, rc, arfs_id);
}
/* Release references */
......@@ -872,8 +892,10 @@ int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
{
struct efx_nic *efx = netdev_priv(net_dev);
struct efx_async_filter_insertion *req;
struct efx_arfs_rule *rule;
struct flow_keys fk;
int slot_idx;
bool new;
int rc;
/* find a free slot */
......@@ -926,12 +948,42 @@ int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
req->spec.rem_port = fk.ports.src;
req->spec.loc_port = fk.ports.dst;
if (efx->rps_hash_table) {
/* Add it to ARFS hash table */
spin_lock(&efx->rps_hash_lock);
rule = efx_rps_hash_add(efx, &req->spec, &new);
if (!rule) {
rc = -ENOMEM;
goto out_unlock;
}
if (new)
rule->arfs_id = efx->rps_next_id++ % RPS_NO_FILTER;
rc = rule->arfs_id;
/* Skip if existing or pending filter already does the right thing */
if (!new && rule->rxq_index == rxq_index &&
rule->filter_id >= EFX_ARFS_FILTER_ID_PENDING)
goto out_unlock;
rule->rxq_index = rxq_index;
rule->filter_id = EFX_ARFS_FILTER_ID_PENDING;
spin_unlock(&efx->rps_hash_lock);
} else {
/* Without an ARFS hash table, we just use arfs_id 0 for all
* filters. This means if multiple flows hash to the same
* flow_id, all but the most recently touched will be eligible
* for expiry.
*/
rc = 0;
}
/* Queue the request */
dev_hold(req->net_dev = net_dev);
INIT_WORK(&req->work, efx_filter_rfs_work);
req->rxq_index = rxq_index;
req->flow_id = flow_id;
schedule_work(&req->work);
return 0;
return rc;
out_unlock:
spin_unlock(&efx->rps_hash_lock);
out_clear:
clear_bit(slot_idx, &efx->rps_slot_map);
return rc;
......
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