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mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-11-08 12:18:42 +00:00

Netindex: converted to spinlocked hash

This commit is contained in:
Maria Matejka 2024-06-08 01:37:24 +02:00
parent 1032bf2543
commit fece55b810
2 changed files with 65 additions and 60 deletions

View File

@ -21,39 +21,38 @@ struct netindex netindex_in_progress;
#define NETINDEX_REHASH netindex_rehash
#define NETINDEX_PARAMS /8, *1, 2, 2, 4, 28
HASH_DEFINE_REHASH_FN(NETINDEX, struct netindex);
static void NETINDEX_REHASH(void *_v) {
netindex_spinhash *v = _v;
int step;
{
NH_LOCK(SKIP_BACK(netindex_hash, hash, v), _);
SPINHASH_REHASH_PREPARE(v,NETINDEX,struct netindex,step);
}
if (!step) return;
if (step > 0) SPINHASH_REHASH_UP(v,NETINDEX,struct netindex,step);
if (step < 0) SPINHASH_REHASH_DOWN(v,NETINDEX,struct netindex,-step);
{
NH_LOCK(SKIP_BACK(netindex_hash, hash, v), _);
SPINHASH_REHASH_FINISH(v,NETINDEX);
}
}
static void netindex_hash_cleanup(void *netindex_hash);
static struct netindex *
net_lock_revive_unlock(struct netindex_hash_private *hp, struct netindex *i)
net_lock_revive_unlock(netindex_hash *h, struct netindex *i)
{
if (!i)
return NULL;
lfuc_lock_revive(&i->uc);
lfuc_unlock(&i->uc, hp->cleanup_list, &hp->cleanup_event);
lfuc_unlock(&i->uc, h->cleanup_list, &h->cleanup_event);
return i;
}
void
netindex_hash_consistency_check(struct netindex_hash_private *nh)
{
uint count = 0;
struct netindex * _Atomic *block = atomic_load_explicit(&nh->block, memory_order_relaxed);
u32 block_size = atomic_load_explicit(&nh->block_size, memory_order_relaxed);
HASH_WALK(nh->hash, next, i)
{
ASSERT_DIE(count < nh->hash.count);
ASSERT_DIE(i->index < block_size);
ASSERT_DIE(atomic_load_explicit(&block[i->index], memory_order_relaxed) == i);
count++;
}
HASH_WALK_END;
ASSERT_DIE(count == nh->hash.count);
}
/*
* Index initialization
*/
@ -72,7 +71,7 @@ netindex_hash_new(pool *sp, event_list *cleanup_target, u8 type)
nh->slab = net_addr_length[type] ? sl_new(nh->pool, sizeof (struct netindex) + net_addr_length[type]) : NULL;
HASH_INIT(nh->hash, nh->pool, NETINDEX_ORDER);
SPINHASH_INIT(nh->hash, NETINDEX, nh->pool, cleanup_target);
atomic_store_explicit(&nh->block_size, NETINDEX_INIT_BLOCK_SIZE, memory_order_release);
atomic_store_explicit(&nh->block,
mb_allocz(nh->pool, NETINDEX_INIT_BLOCK_SIZE * sizeof *nh->block),
@ -95,8 +94,6 @@ netindex_hash_cleanup(void *_nh)
DOMAIN(attrs) dom = nh->lock;
LOCK_DOMAIN(attrs, dom);
EXPENSIVE_CHECK(netindex_hash_consistency_check(nh));
uint kept = 0;
uint bs = atomic_load_explicit(&nh->block_size, memory_order_relaxed);
@ -147,7 +144,7 @@ netindex_hash_cleanup(void *_nh)
ASSERT_DIE(&netindex_in_progress == atomic_exchange_explicit(&block[i], NULL, memory_order_acq_rel));
/* And free it from other structures */
HASH_REMOVE2(nh->hash, NETINDEX, nh->pool, ni);
SPINHASH_REMOVE(nh->hash, NETINDEX, ni);
hmap_clear(&nh->id_map, ni->index);
if (nh->slab)
@ -156,8 +153,6 @@ netindex_hash_cleanup(void *_nh)
mb_free(ni);
}
EXPENSIVE_CHECK(netindex_hash_consistency_check(nh));
if (kept || !nh->deleted_event)
{
UNLOCK_DOMAIN(attrs, dom);
@ -170,11 +165,14 @@ netindex_hash_cleanup(void *_nh)
event_list *t = nh->deleted_target;
/* Check cleanliness */
HASH_WALK(nh->hash, next, i)
SPINHASH_WALK(nh->hash, NETINDEX, i)
bug("Stray netindex in deleted hash");
HASH_WALK_END;
SPINHASH_WALK_END;
/* Pool free is enough to drop everything */
/* Cleanup the spinhash itself */
SPINHASH_FREE(nh->hash);
/* Pool free is enough to drop everything else */
rp_free(nh->pool);
/* And only the lock remains */
@ -190,8 +188,6 @@ netindex_hash_delete(netindex_hash *h, event *e, event_list *t)
{
NH_LOCK(h, hp);
EXPENSIVE_CHECK(netindex_hash_consistency_check(nh));
hp->deleted_event = e;
hp->deleted_target = t;
@ -201,15 +197,28 @@ netindex_hash_delete(netindex_hash *h, event *e, event_list *t)
/*
* Private index manipulation
*/
struct netindex *
net_find_index_fragile(struct netindex_hash_private *hp, const net_addr *n)
static struct netindex *
net_find_index_fragile(netindex_hash *nh, const net_addr *n)
{
ASSERT_DIE(n->type == hp->net_type);
EXPENSIVE_CHECK(netindex_hash_consistency_check(hp));
ASSERT_DIE(n->type == nh->net_type);
u32 h = net_hash(n);
return HASH_FIND(hp->hash, NETINDEX, h, n);
return SPINHASH_FIND(nh->hash, NETINDEX, h, n);
}
static _Bool
net_validate_index(netindex_hash *h, struct netindex *ni)
{
struct netindex * _Atomic *block = atomic_load_explicit(&h->block, memory_order_relaxed);
u32 bs = atomic_load_explicit(&h->block_size, memory_order_relaxed);
ASSERT_DIE(ni->index < bs);
struct netindex *bni = atomic_load_explicit(&block[ni->index], memory_order_acquire);
if (bni == ni)
return 1;
ASSERT_DIE(bni == &netindex_in_progress);
return 0;
}
static struct netindex *
@ -230,7 +239,7 @@ net_new_index_locked(struct netindex_hash_private *hp, const net_addr *n)
};
net_copy(ni->addr, n);
HASH_INSERT2(hp->hash, NETINDEX, hp->pool, ni);
SPINHASH_INSERT(hp->hash, NETINDEX, ni);
struct netindex * _Atomic *block = atomic_load_explicit(&hp->block, memory_order_relaxed);
u32 bs = atomic_load_explicit(&hp->block_size, memory_order_relaxed);
@ -257,7 +266,7 @@ net_new_index_locked(struct netindex_hash_private *hp, const net_addr *n)
ASSERT_DIE(i < nbs);
atomic_store_explicit(&block[i], ni, memory_order_release);
return net_lock_revive_unlock(hp, ni);
return ni;
}
@ -280,26 +289,23 @@ void net_unlock_index(netindex_hash *h, struct netindex *i)
struct netindex *
net_find_index(netindex_hash *h, const net_addr *n)
{
NH_LOCK(h, hp);
struct netindex *ni = net_find_index_fragile(hp, n);
return (ni == &netindex_in_progress) ? NULL : net_lock_revive_unlock(hp, ni);
RCU_ANCHOR(u);
struct netindex *ni = net_find_index_fragile(h, n);
return (ni && net_validate_index(h, ni)) ? net_lock_revive_unlock(h, ni) : NULL;
}
struct netindex *
net_get_index(netindex_hash *h, const net_addr *n)
{
while (1)
{
NH_LOCK(h, hp);
struct netindex *ni = net_find_index_fragile(hp, n);
if (ni == &netindex_in_progress)
continue;
struct netindex *ni = net_find_index(h, n);
if (ni) return ni;
if (ni)
return net_lock_revive_unlock(hp, ni);
else
return net_new_index_locked(hp, n);
}
NH_LOCK(h, hp);
/* Somebody may have added one inbetween */
return net_lock_revive_unlock(h,
(net_find_index_fragile(h, n) ?:
net_new_index_locked(hp, n)));
}
struct netindex *
@ -320,8 +326,5 @@ net_resolve_index(netindex_hash *h, u32 i)
if (ni == &netindex_in_progress)
RCU_RETRY(u);
lfuc_lock_revive(&ni->uc);
net_unlock_index(h, ni);
return ni;
return net_lock_revive_unlock(h, ni);
}

View File

@ -11,20 +11,22 @@
#include "lib/netindex.h"
typedef SPINHASH(struct netindex) netindex_spinhash;
#define NETINDEX_HASH_PUBLIC \
DOMAIN(attrs) lock; /* Assigned lock */ \
event_list *cleanup_list; /* Cleanup event list */ \
event cleanup_event; /* Cleanup event */ \
u8 net_type; /* Which NET_* is stored */ \
uint _Atomic block_size; /* How big block is */ \
struct netindex * _Atomic * _Atomic block; /* u32 to netindex */ \
struct netindex * _Atomic * _Atomic block; /* u32 to netindex */ \
netindex_spinhash hash; /* Spinlocking hashtable */ \
struct netindex_hash_private {
struct { NETINDEX_HASH_PUBLIC; };
struct netindex_hash_private **locked_at;
pool *pool;
slab *slab;
HASH(struct netindex) hash;
struct hmap id_map;
u32 block_epoch;
event *deleted_event;