[net-next,2/2] net: openvswitch: make masks cache size configurable

Message ID	159540647223.619787.13052866492035799125.stgit@ebuild
State	Changes Requested
Delegated to:	David Miller
Headers	show Return-Path: <netdev-owner@vger.kernel.org> From: Eelco Chaudron <echaudro@redhat.com> To: netdev@vger.kernel.org Cc: davem@davemloft.net, dev@openvswitch.org, kuba@kernel.org, pabeni@redhat.com, pshelar@ovn.org Subject: [PATCH net-next 2/2] net: openvswitch: make masks cache size configurable Date: Wed, 22 Jul 2020 10:27:52 +0200 Message-Id: <159540647223.619787.13052866492035799125.stgit@ebuild> In-Reply-To: <159540642765.619787.5484526399990292188.stgit@ebuild> References: <159540642765.619787.5484526399990292188.stgit@ebuild> User-Agent: StGit/0.21 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk
Series	net: openvswitch: masks cache enhancements \| expand [net-next,0/2] net: openvswitch: masks cache enhancements [net-next,1/2] net: openvswitch: add masks cache hit counter [net-next,2/2] net: openvswitch: make masks cache size configurable

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h index 7cb76e5ca7cf..8300cc29dec8 100644 --- a/include/uapi/linux/openvswitch.h +++ b/include/uapi/linux/openvswitch.h @@ -86,6 +86,7 @@ enum ovs_datapath_attr { OVS_DP_ATTR_MEGAFLOW_STATS, /* struct ovs_dp_megaflow_stats */ OVS_DP_ATTR_USER_FEATURES, /* OVS_DP_F_* */ OVS_DP_ATTR_PAD, + OVS_DP_ATTR_MASKS_CACHE_SIZE, __OVS_DP_ATTR_MAX }; diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index a54df1fe3ec4..f08aa1fb9f4b 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -1535,6 +1535,10 @@ static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb, if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features)) goto nla_put_failure; + if (nla_put_u32(skb, OVS_DP_ATTR_MASKS_CACHE_SIZE, + ovs_flow_tbl_masks_cache_size(&dp->table))) + goto nla_put_failure; + genlmsg_end(skb, ovs_header); return 0; @@ -1599,6 +1603,13 @@ static int ovs_dp_change(struct datapath *dp, struct nlattr *a[]) #endif } + if (a[OVS_DP_ATTR_MASKS_CACHE_SIZE]) { + u32 cache_size; + + cache_size = nla_get_u32(a[OVS_DP_ATTR_MASKS_CACHE_SIZE]); + ovs_flow_tbl_masks_cache_resize(&dp->table, cache_size); + } + dp->user_features = user_features; if (dp->user_features & OVS_DP_F_TC_RECIRC_SHARING) diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c index a5912ea05352..1c3590bcf28b 100644 --- a/net/openvswitch/flow_table.c +++ b/net/openvswitch/flow_table.c @@ -38,8 +38,8 @@ #define MASK_ARRAY_SIZE_MIN 16 #define REHASH_INTERVAL (10 * 60 * HZ) +#define MC_DEFAULT_HASH_ENTRIES 256 #define MC_HASH_SHIFT 8 -#define MC_HASH_ENTRIES (1u << MC_HASH_SHIFT) #define MC_HASH_SEGS ((sizeof(uint32_t) * 8) / MC_HASH_SHIFT) static struct kmem_cache *flow_cache; @@ -341,14 +341,74 @@ static void flow_mask_remove(struct flow_table *tbl, struct sw_flow_mask *mask) } } +static void __mask_cache_destroy(struct mask_cache *mc) +{ + if (mc->mask_cache) + free_percpu(mc->mask_cache); + kfree(mc); +} + +static void mask_cache_rcu_cb(struct rcu_head *rcu) +{ + struct mask_cache *mc = container_of(rcu, struct mask_cache, rcu); + + __mask_cache_destroy(mc); +} + +static struct mask_cache *tbl_mask_cache_alloc(u32 size) +{ + struct mask_cache_entry *cache = NULL; + struct mask_cache *new; + + /* Only allow size to be 0, or a power of 2, and does not exceed + * percpu allocation size. + */ + if ((size & (size - 1)) != 0 || + (size * sizeof(struct mask_cache_entry)) > PCPU_MIN_UNIT_SIZE) + return NULL; + + new = kzalloc(sizeof(*new), GFP_KERNEL); + if (!new) + return NULL; + + new->cache_size = size; + if (new->cache_size > 0) { + cache = __alloc_percpu(sizeof(struct mask_cache_entry) * + new->cache_size, + __alignof__(struct mask_cache_entry)); + + if (!cache) { + kfree(new); + return NULL; + } + } + + new->mask_cache = cache; + return new; +} + +void ovs_flow_tbl_masks_cache_resize(struct flow_table *table, u32 size) +{ + struct mask_cache *mc = rcu_dereference(table->mask_cache); + struct mask_cache *new; + + if (size == mc->cache_size || (size & (size - 1)) != 0) + return; + + new = tbl_mask_cache_alloc(size); + if (!new) + return; + + rcu_assign_pointer(table->mask_cache, new); + call_rcu(&mc->rcu, mask_cache_rcu_cb); +} + int ovs_flow_tbl_init(struct flow_table *table) { struct table_instance *ti, *ufid_ti; struct mask_array *ma; - table->mask_cache = __alloc_percpu(sizeof(struct mask_cache_entry) * - MC_HASH_ENTRIES, - __alignof__(struct mask_cache_entry)); + table->mask_cache = tbl_mask_cache_alloc(MC_DEFAULT_HASH_ENTRIES); if (!table->mask_cache) return -ENOMEM; @@ -377,7 +437,7 @@ int ovs_flow_tbl_init(struct flow_table *table) free_mask_array: __mask_array_destroy(ma); free_mask_cache: - free_percpu(table->mask_cache); + __mask_cache_destroy(table->mask_cache); return -ENOMEM; } @@ -454,7 +514,7 @@ void ovs_flow_tbl_destroy(struct flow_table *table) struct table_instance *ti = rcu_dereference_raw(table->ti); struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti); - free_percpu(table->mask_cache); + call_rcu(&table->mask_cache->rcu, mask_cache_rcu_cb); call_rcu(&table->mask_array->rcu, mask_array_rcu_cb); table_instance_destroy(table, ti, ufid_ti, false); } @@ -724,6 +784,7 @@ struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl, u32 *n_mask_hit, u32 *n_cache_hit) { + struct mask_cache *mc = rcu_dereference(tbl->mask_cache); struct mask_array *ma = rcu_dereference(tbl->mask_array); struct table_instance *ti = rcu_dereference(tbl->ti); struct mask_cache_entry *entries, *ce; @@ -733,7 +794,7 @@ struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl, *n_mask_hit = 0; *n_cache_hit = 0; - if (unlikely(!skb_hash)) { + if (unlikely(!skb_hash || mc->cache_size == 0)) { u32 mask_index = 0; u32 cache = 0; @@ -749,11 +810,11 @@ struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl, ce = NULL; hash = skb_hash; - entries = this_cpu_ptr(tbl->mask_cache); + entries = this_cpu_ptr(mc->mask_cache); /* Find the cache entry 'ce' to operate on. */ for (seg = 0; seg < MC_HASH_SEGS; seg++) { - int index = hash & (MC_HASH_ENTRIES - 1); + int index = hash & (mc->cache_size - 1); struct mask_cache_entry *e; e = &entries[index]; @@ -867,6 +928,13 @@ int ovs_flow_tbl_num_masks(const struct flow_table *table) return READ_ONCE(ma->count); } +u32 ovs_flow_tbl_masks_cache_size(const struct flow_table *table) +{ + struct mask_cache *mc = rcu_dereference(table->mask_cache); + + return READ_ONCE(mc->cache_size); +} + static struct table_instance *table_instance_expand(struct table_instance *ti, bool ufid) { diff --git a/net/openvswitch/flow_table.h b/net/openvswitch/flow_table.h index 325e939371d8..f2dba952db2f 100644 --- a/net/openvswitch/flow_table.h +++ b/net/openvswitch/flow_table.h @@ -27,6 +27,12 @@ struct mask_cache_entry { u32 mask_index; }; +struct mask_cache { + struct rcu_head rcu; + u32 cache_size; /* Must be ^2 value. */ + struct mask_cache_entry __percpu *mask_cache; +}; + struct mask_count { int index; u64 counter; @@ -53,7 +59,7 @@ struct table_instance { struct flow_table { struct table_instance __rcu *ti; struct table_instance __rcu *ufid_ti; - struct mask_cache_entry __percpu *mask_cache; + struct mask_cache __rcu *mask_cache; struct mask_array __rcu *mask_array; unsigned long last_rehash; unsigned int count; @@ -77,6 +83,8 @@ int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow, const struct sw_flow_mask *mask); void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow); int ovs_flow_tbl_num_masks(const struct flow_table *table); +u32 ovs_flow_tbl_masks_cache_size(const struct flow_table *table); +void ovs_flow_tbl_masks_cache_resize(struct flow_table *table, u32 size); struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *table, u32 *bucket, u32 *idx); struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *,

[net-next,2/2] net: openvswitch: make masks cache size configurable

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