connectd: optimize gossip_rcvd_filter.

Instead of doing an allocation per entry, put the entry in directly.
This means only 30 bit resolution on 32-bit machines, but if a bit
of gossip gets accidently suppressed that's ok.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2022-06-16 17:02:39 +09:30
parent 87a471af98
commit d922abeaba

View file

@ -1,19 +1,24 @@
#include "config.h"
#include <ccan/crypto/siphash24/siphash24.h>
#include <ccan/htable/htable.h>
#include <ccan/ptrint/ptrint.h>
#include <common/memleak.h>
#include <common/pseudorand.h>
#include <connectd/gossip_rcvd_filter.h>
#include <wire/peer_wire.h>
static u64 msg_key(const u8 *msg)
/* We stash raw integers into ptrs, but leave two bits for htable code to use. */
static size_t msg_key(const u8 *msg)
{
return siphash24(siphash_seed(), msg, tal_bytelen(msg));
size_t key = siphash24(siphash_seed(), msg, tal_bytelen(msg));
/* Avoid 0 and 1, which are invalid in the htable code. */
return key | 0x3;
}
static size_t rehash(const void *key, void *unused)
{
return *(u64 *)key;
return ptr2int(key);
}
static void destroy_msg_map(struct htable *ht)
@ -35,22 +40,12 @@ struct gossip_rcvd_filter {
struct htable *cur, *old;
};
#if DEVELOPER
static void memleak_help_gossip_rcvd_filter(struct htable *memtable,
struct gossip_rcvd_filter *grf)
{
memleak_remove_htable(memtable, grf->cur);
memleak_remove_htable(memtable, grf->old);
}
#endif
struct gossip_rcvd_filter *new_gossip_rcvd_filter(const tal_t *ctx)
{
struct gossip_rcvd_filter *f = tal(ctx, struct gossip_rcvd_filter);
f->cur = new_msg_map(f);
f->old = new_msg_map(f);
memleak_add_helper(f, memleak_help_gossip_rcvd_filter);
return f;
}
@ -108,7 +103,7 @@ static bool is_msg_gossip_broadcast(const u8 *cursor)
return false;
}
static bool extract_msg_key(const u8 *msg, u64 *key)
static bool extract_msg_key(const u8 *msg, size_t *key)
{
if (!is_msg_gossip_broadcast(msg))
return false;
@ -120,30 +115,27 @@ static bool extract_msg_key(const u8 *msg, u64 *key)
/* Add a gossip msg to the received map */
void gossip_rcvd_filter_add(struct gossip_rcvd_filter *f, const u8 *msg)
{
u64 key;
size_t key;
/* We don't attach destructor here directly to tag; would be neat,
* but it's also an extra allocation. */
if (extract_msg_key(msg, &key)) {
htable_add(f->cur, key, tal_dup(f->cur, u64, &key));
/* Don't let it fill up forever though. */
htable_add(f->cur, key, int2ptr(key));
/* Don't let it fill up forever. */
if (htable_count(f->cur) > 10000)
gossip_rcvd_filter_age(f);
}
}
/* htable is fast, but it's also horribly manual. */
static bool msg_map_remove(struct htable *ht, u64 key)
static bool msg_map_remove(struct htable *ht, size_t key)
{
struct htable_iter i;
u64 *c;
void *c;
for (c = htable_firstval(ht, &i, key);
c;
c = htable_nextval(ht, &i, key)) {
if (*c == key) {
if (ptr2int(c) == key) {
htable_del(ht, key, c);
tal_free(c);
return true;
}
}
@ -153,7 +145,7 @@ static bool msg_map_remove(struct htable *ht, u64 key)
/* Is a gossip msg in the received map? (Removes it) */
bool gossip_rcvd_filter_del(struct gossip_rcvd_filter *f, const u8 *msg)
{
u64 key;
size_t key;
if (!extract_msg_key(msg, &key))
return false;