#include <vnet/vnet.h>
-#define LBHASH_ENTRY_PER_BUCKET_LOG2 2
-#define LBHASH_ENTRY_PER_BUCKET (1 << LBHASH_ENTRY_PER_BUCKET_LOG2)
-#define LBHASH_ENTRY_PER_BUCKET_MASK (LBHASH_ENTRY_PER_BUCKET - 1)
+#include <immintrin.h>
+/*
+ * @brief Number of entries per bucket.
+ */
+#define LBHASH_ENTRY_PER_BUCKET 4
+
+#define LB_HASH_DO_NOT_USE_SSE_BUCKETS 0
+
+/*
+ * @brief One bucket contains 4 entries.
+ * Each bucket takes one 64B cache line in memory.
+ */
typedef struct {
- u64 key[5];
- u32 value;
- u32 last_seen;
-} lb_hash_entry_t;
+ CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+ u32 hash[LBHASH_ENTRY_PER_BUCKET];
+ u32 timeout[LBHASH_ENTRY_PER_BUCKET];
+ u32 vip[LBHASH_ENTRY_PER_BUCKET];
+ u32 value[LBHASH_ENTRY_PER_BUCKET];
+} lb_hash_bucket_t;
typedef struct {
u32 buckets_mask;
u32 timeout;
- lb_hash_entry_t entries[];
+ lb_hash_bucket_t buckets[];
} lb_hash_t;
-#define lb_hash_nbuckets(h) (((h)->buckets_mask >> LBHASH_ENTRY_PER_BUCKET_LOG2) + 1)
+#define lb_hash_nbuckets(h) (((h)->buckets_mask) + 1)
#define lb_hash_size(h) ((h)->buckets_mask + LBHASH_ENTRY_PER_BUCKET)
-#define lb_hash_foreach_entry(h, e) \
- for (e = (h)->entries; e < h->entries + lb_hash_size(h); e++)
+#define lb_hash_foreach_bucket(h, bucket) \
+ for (bucket = (h)->buckets; \
+ bucket < (h)->buckets + lb_hash_nbuckets(h); \
+ bucket++)
+
+#define lb_hash_foreach_entry(h, bucket, i) \
+ lb_hash_foreach_bucket(h, bucket) \
+ for (i = 0; i < LBHASH_ENTRY_PER_BUCKET; i++)
-#define lb_hash_foreach_valid_entry(h, e, now) \
- lb_hash_foreach_entry(h, e) \
- if (!clib_u32_loop_gt((now), (e)->last_seen + (h)->timeout))
+#define lb_hash_foreach_valid_entry(h, bucket, i, now) \
+ lb_hash_foreach_entry(h, bucket, i) \
+ if (!clib_u32_loop_gt((now), bucket->timeout[i]))
static_always_inline
lb_hash_t *lb_hash_alloc(u32 buckets, u32 timeout)
{
- if ((!is_pow2(buckets)) ||
- ((buckets << LBHASH_ENTRY_PER_BUCKET_LOG2) == 0))
+ if (!is_pow2(buckets))
return NULL;
// Allocate 1 more bucket for prefetch
- u32 size = sizeof(lb_hash_t) + ((buckets << LBHASH_ENTRY_PER_BUCKET_LOG2) + 1)* sizeof(lb_hash_entry_t);
+ u32 size = ((u64)&((lb_hash_t *)(0))->buckets[0]) +
+ sizeof(lb_hash_bucket_t) * (buckets + 1);
u8 *mem = 0;
lb_hash_t *h;
vec_alloc_aligned(mem, size, CLIB_CACHE_LINE_BYTES);
h = (lb_hash_t *)mem;
- h->buckets_mask = (buckets - 1) << LBHASH_ENTRY_PER_BUCKET_LOG2;
+ h->buckets_mask = (buckets - 1);
h->timeout = timeout;
return h;
}
static_always_inline
void lb_hash_free(lb_hash_t *h)
{
- vec_free(h);
+ u8 *mem = (u8 *)h;
+ vec_free(mem);
}
#if __SSE4_2__
static_always_inline
-u32 lb_hash_crc_u32(u32 data, u32 value)
-{
- __asm__ volatile( "crc32l %[data], %[value];"
- : [value] "+r" (value)
- : [data] "rm" (data));
- return value;
-}
-
-static_always_inline
-u32 lb_hash_hash(u64 k[5])
+u32 lb_hash_hash(u64 k0, u64 k1, u64 k2, u64 k3, u64 k4)
{
- u32 * dp = (u32 *) k;
- u32 value = 0;
-
- value = lb_hash_crc_u32 (dp[0], value);
- value = lb_hash_crc_u32 (dp[1], value);
- value = lb_hash_crc_u32 (dp[2], value);
- value = lb_hash_crc_u32 (dp[3], value);
- value = lb_hash_crc_u32 (dp[4], value);
- value = lb_hash_crc_u32 (dp[5], value);
- value = lb_hash_crc_u32 (dp[6], value);
- value = lb_hash_crc_u32 (dp[7], value);
- value = lb_hash_crc_u32 (dp[8], value);
- value = lb_hash_crc_u32 (dp[9], value);
- return value;
+ u64 val = 0;
+ val = _mm_crc32_u64(val, k0);
+ val = _mm_crc32_u64(val, k1);
+ val = _mm_crc32_u64(val, k2);
+ val = _mm_crc32_u64(val, k3);
+ val = _mm_crc32_u64(val, k4);
+ return (u32) val;
}
#else
static_always_inline
-u32 lb_hash_hash(u64 k[5])
+u32 lb_hash_hash(u64 k0, u64 k1, u64 k2, u64 k3, u64 k4)
{
- u64 tmp = k[0] ^ k[1] ^ k[2] ^ k[3] ^ k[4];
+ u64 tmp = k0 ^ k1 ^ k2 ^ k3 ^ k4;
return (u32)clib_xxhash (tmp);
}
#endif
-
+static_always_inline
+void lb_hash_prefetch_bucket(lb_hash_t *ht, u32 hash)
+{
+ lb_hash_bucket_t *bucket = &ht->buckets[hash & ht->buckets_mask];
+ CLIB_PREFETCH(bucket, sizeof(*bucket), READ);
+}
static_always_inline
-void lb_hash_get(lb_hash_t *h, u64 k[5], u32 hash, u32 time_now, u32 *available_index, u32 *value)
+void lb_hash_get(lb_hash_t *ht, u32 hash, u32 vip, u32 time_now,
+ u32 *available_index, u32 *found_value)
{
- lb_hash_entry_t *e = &h->entries[hash & h->buckets_mask];
- u32 i;
- *value = ~0;
+ lb_hash_bucket_t *bucket = &ht->buckets[hash & ht->buckets_mask];
+ *found_value = ~0;
*available_index = ~0;
- CLIB_PREFETCH (&(e[1]), sizeof(lb_hash_entry_t), STORE);
- for (i=0; i<LBHASH_ENTRY_PER_BUCKET; i++) {
- CLIB_PREFETCH (&(e[i+2]), sizeof(lb_hash_entry_t), STORE); //+2 somehow performs best
- u64 cmp =
- (e[i].key[0] ^ k[0]) |
- (e[i].key[1] ^ k[1]) |
- (e[i].key[2] ^ k[2]) |
- (e[i].key[3] ^ k[3]) |
- (e[i].key[4] ^ k[4]);
-
- u8 timeouted = clib_u32_loop_gt(time_now, e[i].last_seen + h->timeout);
-
- *value = (cmp || timeouted)?*value:e[i].value;
- e[i].last_seen = (cmp || timeouted)?e[i].last_seen:time_now;
- *available_index = (timeouted && (*available_index == ~0))?(&e[i] - h->entries):*available_index;
-
- if (!cmp)
- return;
+#if __SSE4_2__ && LB_HASH_DO_NOT_USE_SSE_BUCKETS == 0
+ u32 bitmask, found_index;
+ __m128i mask;
+
+ // mask[*] = timeout[*] > now
+ mask = _mm_cmpgt_epi32(_mm_loadu_si128 ((__m128i *) bucket->timeout),
+ _mm_set1_epi32 (time_now));
+ // bitmask[*] = now <= timeout[*/4]
+ bitmask = (~_mm_movemask_epi8(mask)) & 0xffff;
+ // Get first index with now <= timeout[*], if any.
+ *available_index = (bitmask)?__builtin_ctz(bitmask)/4:*available_index;
+
+ // mask[*] = (timeout[*] > now) && (hash[*] == hash)
+ mask = _mm_and_si128(mask,
+ _mm_cmpeq_epi32(
+ _mm_loadu_si128 ((__m128i *) bucket->hash),
+ _mm_set1_epi32 (hash)));
+
+ // Load the array of vip values
+ // mask[*] = (timeout[*] > now) && (hash[*] == hash) && (vip[*] == vip)
+ mask = _mm_and_si128(mask,
+ _mm_cmpeq_epi32(
+ _mm_loadu_si128 ((__m128i *) bucket->vip),
+ _mm_set1_epi32 (vip)));
+
+ // mask[*] = (timeout[*x4] > now) && (hash[*x4] == hash) && (vip[*x4] == vip)
+ bitmask = _mm_movemask_epi8(mask);
+ // Get first index, if any
+ found_index = (bitmask)?__builtin_ctzll(bitmask)/4:0;
+ ASSERT(found_index < 4);
+ *found_value = (bitmask)?bucket->value[found_index]:*found_value;
+ bucket->timeout[found_index] =
+ (bitmask)?time_now + ht->timeout:bucket->timeout[found_index];
+#else
+ u32 i;
+ for (i = 0; i < LBHASH_ENTRY_PER_BUCKET; i++) {
+ u8 cmp = (bucket->hash[i] == hash && bucket->vip[i] == vip);
+ u8 timeouted = clib_u32_loop_gt(time_now, bucket->timeout[i]);
+ *found_value = (cmp || timeouted)?*found_value:bucket->value[i];
+ bucket->timeout[i] = (cmp || timeouted)?time_now + ht->timeout:bucket->timeout[i];
+ *available_index = (timeouted && (*available_index == ~0))?i:*available_index;
+
+ if (!cmp)
+ return;
}
+#endif
}
static_always_inline
-u32 lb_hash_available_value(lb_hash_t *h, u32 available_index)
+u32 lb_hash_available_value(lb_hash_t *h, u32 hash, u32 available_index)
{
- return h->entries[available_index].value;
+ return h->buckets[hash & h->buckets_mask].value[available_index];
}
static_always_inline
-u32 lb_hash_put(lb_hash_t *h, u64 k[5], u32 value, u32 available_index, u32 time_now)
+void lb_hash_put(lb_hash_t *h, u32 hash, u32 value, u32 vip,
+ u32 available_index, u32 time_now)
{
- lb_hash_entry_t *e = &h->entries[available_index];
- e->key[0] = k[0];
- e->key[1] = k[1];
- e->key[2] = k[2];
- e->key[3] = k[3];
- e->key[4] = k[4];
- e->value = value;
- e->last_seen = time_now;
- return 0;
+ lb_hash_bucket_t *bucket = &h->buckets[hash & h->buckets_mask];
+ bucket->hash[available_index] = hash;
+ bucket->value[available_index] = value;
+ bucket->timeout[available_index] = time_now + h->timeout;
+ bucket->vip[available_index] = vip;
}
static_always_inline
u32 lb_hash_elts(lb_hash_t *h, u32 time_now)
{
u32 tot = 0;
- lb_hash_entry_t *e;
- lb_hash_foreach_valid_entry(h, e, time_now) {
+ lb_hash_bucket_t *bucket;
+ u32 i;
+ lb_hash_foreach_valid_entry(h, bucket, i, time_now) {
tot++;
}
return tot;
Code Review / vpp.git / blobdiff