@@ -82,7 +82,7 @@ struct datapath {
u32 max_headroom;
/* Switch meters. */
- struct hlist_head *meters;
+ struct dp_meter_table meter_tbl;
};
/**
@@ -19,8 +19,6 @@
#include "datapath.h"
#include "meter.h"
-#define METER_HASH_BUCKETS 1024
-
static const struct nla_policy meter_policy[OVS_METER_ATTR_MAX + 1] = {
[OVS_METER_ATTR_ID] = { .type = NLA_U32, },
[OVS_METER_ATTR_KBPS] = { .type = NLA_FLAG },
@@ -39,6 +37,11 @@ static const struct nla_policy band_policy[OVS_BAND_ATTR_MAX + 1] = {
[OVS_BAND_ATTR_STATS] = { .len = sizeof(struct ovs_flow_stats) },
};
+static u32 meter_hash(struct dp_meter_instance *ti, u32 id)
+{
+ return id % ti->n_meters;
+}
+
static void ovs_meter_free(struct dp_meter *meter)
{
if (!meter)
@@ -47,40 +50,153 @@ static void ovs_meter_free(struct dp_meter *meter)
kfree_rcu(meter, rcu);
}
-static struct hlist_head *meter_hash_bucket(const struct datapath *dp,
- u32 meter_id)
-{
- return &dp->meters[meter_id & (METER_HASH_BUCKETS - 1)];
-}
-
/* Call with ovs_mutex or RCU read lock. */
-static struct dp_meter *lookup_meter(const struct datapath *dp,
+static struct dp_meter *lookup_meter(const struct dp_meter_table *tbl,
u32 meter_id)
{
+ struct dp_meter_instance *ti = rcu_dereference_ovsl(tbl->ti);
+ u32 hash = meter_hash(ti, meter_id);
struct dp_meter *meter;
- struct hlist_head *head;
- head = meter_hash_bucket(dp, meter_id);
- hlist_for_each_entry_rcu(meter, head, dp_hash_node,
- lockdep_ovsl_is_held()) {
- if (meter->id == meter_id)
- return meter;
- }
+ meter = rcu_dereference_ovsl(ti->dp_meters[hash]);
+ if (meter && likely(meter->id == meter_id))
+ return meter;
+
return NULL;
}
-static void attach_meter(struct datapath *dp, struct dp_meter *meter)
+static struct dp_meter_instance *dp_meter_instance_alloc(const u32 size)
+{
+ struct dp_meter_instance *ti;
+
+ ti = kvzalloc(sizeof(*ti) +
+ sizeof(struct dp_meter *) * size,
+ GFP_KERNEL);
+ if (!ti)
+ return NULL;
+
+ ti->n_meters = size;
+
+ return ti;
+}
+
+static void dp_meter_instance_free(struct dp_meter_instance *ti)
+{
+ kvfree(ti);
+}
+
+static void dp_meter_instance_free_rcu(struct rcu_head *rcu)
+{
+ struct dp_meter_instance *ti;
+
+ ti = container_of(rcu, struct dp_meter_instance, rcu);
+ kvfree(ti);
+}
+
+static int
+dp_meter_instance_realloc(struct dp_meter_table *tbl, u32 size)
+{
+ struct dp_meter_instance *ti = rcu_dereference_ovsl(tbl->ti);
+ int n_meters = min(size, ti->n_meters);
+ struct dp_meter_instance *new_ti;
+ int i;
+
+ new_ti = dp_meter_instance_alloc(size);
+ if (!new_ti)
+ return -ENOMEM;
+
+ for (i = 0; i < n_meters; i++)
+ new_ti->dp_meters[i] =
+ rcu_dereference_ovsl(ti->dp_meters[i]);
+
+ rcu_assign_pointer(tbl->ti, new_ti);
+ call_rcu(&ti->rcu, dp_meter_instance_free_rcu);
+
+ return 0;
+}
+
+static void dp_meter_instance_insert(struct dp_meter_instance *ti,
+ struct dp_meter *meter)
+{
+ u32 hash;
+
+ hash = meter_hash(ti, meter->id);
+ rcu_assign_pointer(ti->dp_meters[hash], meter);
+}
+
+static void dp_meter_instance_remove(struct dp_meter_instance *ti,
+ struct dp_meter *meter)
{
- struct hlist_head *head = meter_hash_bucket(dp, meter->id);
+ u32 hash;
- hlist_add_head_rcu(&meter->dp_hash_node, head);
+ hash = meter_hash(ti, meter->id);
+ RCU_INIT_POINTER(ti->dp_meters[hash], NULL);
}
-static void detach_meter(struct dp_meter *meter)
+static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
{
+ struct dp_meter_instance *ti = rcu_dereference_ovsl(tbl->ti);
+ u32 hash = meter_hash(ti, meter->id);
+
+ /* In generally, slots selected should be empty, because
+ * OvS uses id-pool to fetch a available id.
+ */
+ if (unlikely(rcu_dereference_ovsl(ti->dp_meters[hash])))
+ return -EBUSY;
+
+ dp_meter_instance_insert(ti, meter);
+
+ /* That function is thread-safe. */
+ if (++tbl->count >= ti->n_meters)
+ if (dp_meter_instance_realloc(tbl, ti->n_meters * 2))
+ goto expand_err;
+
+ return 0;
+
+expand_err:
+ dp_meter_instance_remove(ti, meter);
+ tbl->count--;
+ return -ENOMEM;
+}
+
+static int detach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
+{
+ struct dp_meter_instance *ti;
+
ASSERT_OVSL();
- if (meter)
- hlist_del_rcu(&meter->dp_hash_node);
+ if (!meter)
+ return 0;
+
+ ti = rcu_dereference_ovsl(tbl->ti);
+ dp_meter_instance_remove(ti, meter);
+
+ tbl->count--;
+
+ /* Shrink the meter array if necessary. */
+ if (ti->n_meters > DP_METER_ARRAY_SIZE_MIN &&
+ tbl->count <= (ti->n_meters / 4)) {
+ int half_size = ti->n_meters / 2;
+ int i;
+
+ /* Avoid hash collision, don't move slots to other place.
+ * Make sure there are no references of meters in array
+ * which will be released.
+ */
+ for (i = half_size; i < ti->n_meters; i++)
+ if (rcu_dereference_ovsl(ti->dp_meters[i]))
+ goto out;
+
+ if (dp_meter_instance_realloc(tbl, half_size))
+ goto shrink_err;
+ }
+
+out:
+ return 0;
+
+shrink_err:
+ dp_meter_instance_insert(ti, meter);
+ tbl->count++;
+ return -ENOMEM;
}
static struct sk_buff *
@@ -273,6 +389,7 @@ static int ovs_meter_cmd_set(struct sk_buff *skb, struct genl_info *info)
struct sk_buff *reply;
struct ovs_header *ovs_reply_header;
struct ovs_header *ovs_header = info->userhdr;
+ struct dp_meter_table *meter_tbl;
struct datapath *dp;
int err;
u32 meter_id;
@@ -300,12 +417,18 @@ static int ovs_meter_cmd_set(struct sk_buff *skb, struct genl_info *info)
goto exit_unlock;
}
+ meter_tbl = &dp->meter_tbl;
meter_id = nla_get_u32(a[OVS_METER_ATTR_ID]);
- /* Cannot fail after this. */
- old_meter = lookup_meter(dp, meter_id);
- detach_meter(old_meter);
- attach_meter(dp, meter);
+ old_meter = lookup_meter(meter_tbl, meter_id);
+ err = detach_meter(meter_tbl, old_meter);
+ if (err)
+ goto exit_unlock;
+
+ err = attach_meter(meter_tbl, meter);
+ if (err)
+ goto exit_unlock;
+
ovs_unlock();
/* Build response with the meter_id and stats from
@@ -337,14 +460,14 @@ static int ovs_meter_cmd_set(struct sk_buff *skb, struct genl_info *info)
static int ovs_meter_cmd_get(struct sk_buff *skb, struct genl_info *info)
{
- struct nlattr **a = info->attrs;
- u32 meter_id;
struct ovs_header *ovs_header = info->userhdr;
struct ovs_header *ovs_reply_header;
+ struct nlattr **a = info->attrs;
+ struct dp_meter *meter;
+ struct sk_buff *reply;
struct datapath *dp;
+ u32 meter_id;
int err;
- struct sk_buff *reply;
- struct dp_meter *meter;
if (!a[OVS_METER_ATTR_ID])
return -EINVAL;
@@ -365,7 +488,7 @@ static int ovs_meter_cmd_get(struct sk_buff *skb, struct genl_info *info)
}
/* Locate meter, copy stats. */
- meter = lookup_meter(dp, meter_id);
+ meter = lookup_meter(&dp->meter_tbl, meter_id);
if (!meter) {
err = -ENOENT;
goto exit_unlock;
@@ -390,18 +513,17 @@ static int ovs_meter_cmd_get(struct sk_buff *skb, struct genl_info *info)
static int ovs_meter_cmd_del(struct sk_buff *skb, struct genl_info *info)
{
- struct nlattr **a = info->attrs;
- u32 meter_id;
struct ovs_header *ovs_header = info->userhdr;
struct ovs_header *ovs_reply_header;
+ struct nlattr **a = info->attrs;
+ struct dp_meter *old_meter;
+ struct sk_buff *reply;
struct datapath *dp;
+ u32 meter_id;
int err;
- struct sk_buff *reply;
- struct dp_meter *old_meter;
if (!a[OVS_METER_ATTR_ID])
return -EINVAL;
- meter_id = nla_get_u32(a[OVS_METER_ATTR_ID]);
reply = ovs_meter_cmd_reply_start(info, OVS_METER_CMD_DEL,
&ovs_reply_header);
@@ -416,14 +538,19 @@ static int ovs_meter_cmd_del(struct sk_buff *skb, struct genl_info *info)
goto exit_unlock;
}
- old_meter = lookup_meter(dp, meter_id);
+ meter_id = nla_get_u32(a[OVS_METER_ATTR_ID]);
+ old_meter = lookup_meter(&dp->meter_tbl, meter_id);
if (old_meter) {
spin_lock_bh(&old_meter->lock);
err = ovs_meter_cmd_reply_stats(reply, meter_id, old_meter);
WARN_ON(err);
spin_unlock_bh(&old_meter->lock);
- detach_meter(old_meter);
+
+ err = detach_meter(&dp->meter_tbl, old_meter);
+ if (err)
+ goto exit_unlock;
}
+
ovs_unlock();
ovs_meter_free(old_meter);
genlmsg_end(reply, ovs_reply_header);
@@ -443,16 +570,16 @@ static int ovs_meter_cmd_del(struct sk_buff *skb, struct genl_info *info)
bool ovs_meter_execute(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key, u32 meter_id)
{
- struct dp_meter *meter;
- struct dp_meter_band *band;
long long int now_ms = div_u64(ktime_get_ns(), 1000 * 1000);
long long int long_delta_ms;
- u32 delta_ms;
- u32 cost;
+ struct dp_meter_band *band;
+ struct dp_meter *meter;
int i, band_exceeded_max = -1;
u32 band_exceeded_rate = 0;
+ u32 delta_ms;
+ u32 cost;
- meter = lookup_meter(dp, meter_id);
+ meter = lookup_meter(&dp->meter_tbl, meter_id);
/* Do not drop the packet when there is no meter. */
if (!meter)
return false;
@@ -570,32 +697,27 @@ struct genl_family dp_meter_genl_family __ro_after_init = {
int ovs_meters_init(struct datapath *dp)
{
- int i;
+ struct dp_meter_table *tbl = &dp->meter_tbl;
+ struct dp_meter_instance *ti;
- dp->meters = kmalloc_array(METER_HASH_BUCKETS,
- sizeof(struct hlist_head), GFP_KERNEL);
-
- if (!dp->meters)
+ ti = dp_meter_instance_alloc(DP_METER_ARRAY_SIZE_MIN);
+ if (!ti)
return -ENOMEM;
- for (i = 0; i < METER_HASH_BUCKETS; i++)
- INIT_HLIST_HEAD(&dp->meters[i]);
+ rcu_assign_pointer(tbl->ti, ti);
+ tbl->count = 0;
return 0;
}
void ovs_meters_exit(struct datapath *dp)
{
+ struct dp_meter_table *tbl = &dp->meter_tbl;
+ struct dp_meter_instance *ti = rcu_dereference_raw(tbl->ti);
int i;
- for (i = 0; i < METER_HASH_BUCKETS; i++) {
- struct hlist_head *head = &dp->meters[i];
- struct dp_meter *meter;
- struct hlist_node *n;
-
- hlist_for_each_entry_safe(meter, n, head, dp_hash_node)
- kfree(meter);
- }
+ for (i = 0; i < ti->n_meters; i++)
+ ovs_meter_free(ti->dp_meters[i]);
- kfree(dp->meters);
+ dp_meter_instance_free(ti);
}
@@ -13,11 +13,13 @@
#include <linux/openvswitch.h>
#include <linux/genetlink.h>
#include <linux/skbuff.h>
+#include <linux/bits.h>
#include "flow.h"
struct datapath;
#define DP_MAX_BANDS 1
+#define DP_METER_ARRAY_SIZE_MIN BIT_ULL(10)
struct dp_meter_band {
u32 type;
@@ -30,9 +32,6 @@ struct dp_meter_band {
struct dp_meter {
spinlock_t lock; /* Per meter lock */
struct rcu_head rcu;
- struct hlist_node dp_hash_node; /*Element in datapath->meters
- * hash table.
- */
u32 id;
u16 kbps:1, keep_stats:1;
u16 n_bands;
@@ -42,6 +41,17 @@ struct dp_meter {
struct dp_meter_band bands[];
};
+struct dp_meter_instance {
+ struct rcu_head rcu;
+ u32 n_meters;
+ struct dp_meter __rcu *dp_meters[];
+};
+
+struct dp_meter_table {
+ struct dp_meter_instance __rcu *ti;
+ u32 count;
+};
+
extern struct genl_family dp_meter_genl_family;
int ovs_meters_init(struct datapath *dp);
void ovs_meters_exit(struct datapath *dp);