X-Git-Url: https://pd.if.org/git/?p=nbds;a=blobdiff_plain;f=struct%2Fhashtable.c;h=523a29a5fd7664c591809e72fdec314f4ecb9e82;hp=45c9ffc6f9f98ad479c33b4dd5ff00a557515a1e;hb=a1fae129c758d7ea83dfdbb5f14ec1df12f0aa34;hpb=052506ff082f134f00834f666653819e18d9bddf diff --git a/struct/hashtable.c b/struct/hashtable.c index 45c9ffc..523a29a 100644 --- a/struct/hashtable.c +++ b/struct/hashtable.c @@ -29,17 +29,17 @@ typedef struct string { char val[]; } string_t; -typedef struct hash_table_i { +typedef struct hti { volatile entry_t *table; - hash_table_t *ht; // parent ht; - struct hash_table_i *next; - struct hash_table_i *next_free; + hashtable_t *ht; // parent ht; + struct hti *next; + struct hti *next_free; unsigned int scale; int max_probe; int count; // TODO: make these counters distributed int num_entries_copied; int scan; -} hash_table_i_t; +} hashtable_i_t; static const uint64_t COPIED_VALUE = -1; static const uint64_t TOMBSTONE = STRIP_TAG(-1); @@ -50,7 +50,7 @@ static const unsigned MIN_SCALE = 4; // min 16 entries (4 buckets) static const unsigned MAX_BUCKETS_TO_PROBE = 250; static int hti_copy_entry - (hash_table_i_t *ht1, volatile entry_t *e, uint32_t e_key_hash, hash_table_i_t *ht2); + (hashtable_i_t *ht1, volatile entry_t *e, uint32_t e_key_hash, hashtable_i_t *ht2); // Choose the next bucket to probe using the high-order bits of . static inline int get_next_ndx(int old_ndx, uint32_t key_hash, int ht_scale) { @@ -80,7 +80,7 @@ static inline int ht_key_equals (uint64_t a, uint32_t b_hash, const char *b_valu // // Record if the entry being returned is empty. Otherwise the caller will have to waste time with // ht_key_equals() to confirm that it did not lose a race to fill an empty entry. -static volatile entry_t *hti_lookup (hash_table_i_t *hti, uint32_t key_hash, const char *key_val, uint32_t key_len, int *is_empty) { +static volatile entry_t *hti_lookup (hashtable_i_t *hti, uint32_t key_hash, const char *key_val, uint32_t key_len, int *is_empty) { TRACE("h2", "hti_lookup(key %p in hti %p)", key_val, hti); *is_empty = 0; @@ -117,16 +117,16 @@ static volatile entry_t *hti_lookup (hash_table_i_t *hti, uint32_t key_hash, con return NULL; } -// Allocate and initialize a hash_table_i_t with 2^ entries. -static hash_table_i_t *hti_alloc (hash_table_t *parent, int scale) { +// Allocate and initialize a hashtable_i_t with 2^ entries. +static hashtable_i_t *hti_alloc (hashtable_t *parent, int scale) { // Include enough slop to align the actual table on a cache line boundry - size_t n = sizeof(hash_table_i_t) + size_t n = sizeof(hashtable_i_t) + sizeof(entry_t) * (1 << scale) + (CACHE_LINE_SIZE - 1); - hash_table_i_t *hti = (hash_table_i_t *)calloc(n, 1); + hashtable_i_t *hti = (hashtable_i_t *)calloc(n, 1); // Align the table of hash entries on a cache line boundry. - hti->table = (entry_t *)(((uint64_t)hti + sizeof(hash_table_i_t) + (CACHE_LINE_SIZE-1)) + hti->table = (entry_t *)(((uint64_t)hti + sizeof(hashtable_i_t) + (CACHE_LINE_SIZE-1)) & ~(CACHE_LINE_SIZE-1)); hti->scale = scale; @@ -148,8 +148,8 @@ static hash_table_i_t *hti_alloc (hash_table_t *parent, int scale) { // Called when runs out of room for new keys. // -// Initiates a copy by creating a larger hash_table_i_t and installing it in next>. -static void hti_start_copy (hash_table_i_t *hti) { +// Initiates a copy by creating a larger hashtable_i_t and installing it in next>. +static void hti_start_copy (hashtable_i_t *hti) { TRACE("h0", "hti_start_copy(hti %p scale %llu)", hti, hti->scale); // heuristics to determine the size of the new table @@ -159,8 +159,8 @@ static void hti_start_copy (hash_table_i_t *hti) { new_scale += (count > (1 << (new_scale - 2))); // double size again if more than 1/2 full // Allocate the new table and attempt to install it. - hash_table_i_t *next = hti_alloc(hti->ht, new_scale); - hash_table_i_t *old_next = SYNC_CAS(&hti->next, NULL, next); + hashtable_i_t *next = hti_alloc(hti->ht, new_scale); + hashtable_i_t *old_next = SYNC_CAS(&hti->next, NULL, next); if (old_next != NULL) { // Another thread beat us to it. TRACE("h0", "hti_start_copy: lost race to install new hti; found %p", old_next, 0); @@ -174,8 +174,8 @@ static void hti_start_copy (hash_table_i_t *hti) { // // Return 1 unless is already copied (then return 0), so the caller can account for the total // number of entries left to copy. -static int hti_copy_entry (hash_table_i_t *ht1, volatile entry_t *ht1_e, uint32_t key_hash, - hash_table_i_t *ht2) { +static int hti_copy_entry (hashtable_i_t *ht1, volatile entry_t *ht1_e, uint32_t key_hash, + hashtable_i_t *ht2) { TRACE("h2", "hti_copy_entry: entry %p to table %p", ht1_e, ht2); assert(ht1); assert(ht1->next); @@ -291,11 +291,11 @@ static int hti_copy_entry (hash_table_i_t *ht1, volatile entry_t *ht1_e, uint32_ // // NOTE: the returned value matches iff the set succeeds // -// Certain values of have special meaning. If is HT_EXPECT_EXISTS then any +// Certain values of have special meaning. If is EXPECT_EXISTS then any // real value matches (i.e. not a TOMBSTONE or DOES_NOT_EXIST) as long as is in the table. If -// is HT_EXPECT_WHATEVER then skip the test entirely. +// is EXPECT_WHATEVER then skip the test entirely. // -static uint64_t hti_compare_and_set (hash_table_i_t *hti, uint32_t key_hash, const char *key_val, +static uint64_t hti_compare_and_set (hashtable_i_t *hti, uint32_t key_hash, const char *key_val, uint32_t key_len, uint64_t expected, uint64_t new) { TRACE("h1", "hti_compare_and_set: hti %p key %p", hti, key_val); TRACE("h1", "hti_compare_and_set: value %p expect %p", new, expected); @@ -317,7 +317,7 @@ static uint64_t hti_compare_and_set (hash_table_i_t *hti, uint32_t key_hash, con // Install in the table if it doesn't exist. if (is_empty) { TRACE("h0", "hti_compare_and_set: entry %p is empty", e, 0); - if (expected != HT_EXPECT_WHATEVER && expected != HT_EXPECT_NOT_EXISTS) + if (expected != EXPECT_WHATEVER && expected != EXPECT_DOES_NOT_EXIST) return DOES_NOT_EXIST; // No need to do anything, is already deleted. @@ -349,7 +349,7 @@ static uint64_t hti_compare_and_set (hash_table_i_t *hti, uint32_t key_hash, con uint64_t e_value = e->value; if (EXPECT_FALSE(IS_TAGGED(e_value))) { if (e_value != COPIED_VALUE) { - int did_copy = hti_copy_entry(hti, e, key_hash, ((volatile hash_table_i_t *)hti)->next); + int did_copy = hti_copy_entry(hti, e, key_hash, ((volatile hashtable_i_t *)hti)->next); if (did_copy) { SYNC_ADD(&hti->num_entries_copied, 1); } @@ -362,8 +362,8 @@ static uint64_t hti_compare_and_set (hash_table_i_t *hti, uint32_t key_hash, con // Fail if the old value is not consistent with the caller's expectation. int old_existed = (e_value != TOMBSTONE && e_value != DOES_NOT_EXIST); - if (EXPECT_FALSE(expected != HT_EXPECT_WHATEVER && expected != e_value)) { - if (EXPECT_FALSE(expected != (old_existed ? HT_EXPECT_EXISTS : HT_EXPECT_NOT_EXISTS))) { + if (EXPECT_FALSE(expected != EXPECT_WHATEVER && expected != e_value)) { + if (EXPECT_FALSE(expected != (old_existed ? EXPECT_EXISTS : EXPECT_DOES_NOT_EXIST))) { TRACE("h1", "hti_compare_and_set: value %p expected by caller not found; found value %p", expected, e_value); return e_value; @@ -396,7 +396,7 @@ static uint64_t hti_compare_and_set (hash_table_i_t *hti, uint32_t key_hash, con } // -static uint64_t hti_get (hash_table_i_t *hti, uint32_t key_hash, const char *key_val, uint32_t key_len) { +static uint64_t hti_get (hashtable_i_t *hti, uint32_t key_hash, const char *key_val, uint32_t key_len) { assert(key_val); int is_empty; @@ -406,7 +406,7 @@ static uint64_t hti_get (hash_table_i_t *hti, uint32_t key_hash, const char *key // searching the table. In that case, if a copy is in progress the key // might exist in the copy. if (EXPECT_FALSE(e == NULL)) { - if (((volatile hash_table_i_t *)hti)->next != NULL) + if (((volatile hashtable_i_t *)hti)->next != NULL) return hti_get(hti->next, key_hash, key_val, key_len); // recursive tail-call return DOES_NOT_EXIST; } @@ -418,24 +418,24 @@ static uint64_t hti_get (hash_table_i_t *hti, uint32_t key_hash, const char *key uint64_t e_value = e->value; if (EXPECT_FALSE(IS_TAGGED(e_value))) { if (EXPECT_FALSE(e_value != COPIED_VALUE)) { - int did_copy = hti_copy_entry(hti, e, key_hash, ((volatile hash_table_i_t *)hti)->next); + int did_copy = hti_copy_entry(hti, e, key_hash, ((volatile hashtable_i_t *)hti)->next); if (did_copy) { SYNC_ADD(&hti->num_entries_copied, 1); } } - return hti_get(((volatile hash_table_i_t *)hti)->next, key_hash, key_val, key_len); // tail-call + return hti_get(((volatile hashtable_i_t *)hti)->next, key_hash, key_val, key_len); // tail-call } return (e_value == TOMBSTONE) ? DOES_NOT_EXIST : e_value; } // -uint64_t ht_get (hash_table_t *ht, const char *key_val, uint32_t key_len) { +uint64_t ht_get (hashtable_t *ht, const char *key_val, uint32_t key_len) { return hti_get(*ht, murmur32(key_val, key_len), key_val, key_len); } // -uint64_t ht_compare_and_set (hash_table_t *ht, const char *key_val, uint32_t key_len, +uint64_t ht_compare_and_set (hashtable_t *ht, const char *key_val, uint32_t key_len, uint64_t expected_val, uint64_t new_val) { TRACE("h2", "ht_compare_and_set: key %p len %u", key_val, key_len); @@ -443,7 +443,7 @@ uint64_t ht_compare_and_set (hash_table_t *ht, const char *key_val, uint32_t key assert(key_val); assert(!IS_TAGGED(new_val) && new_val != DOES_NOT_EXIST); - hash_table_i_t *hti = *ht; + hashtable_i_t *hti = *ht; // Help with an ongoing copy. if (EXPECT_FALSE(hti->next != NULL)) { @@ -504,12 +504,12 @@ uint64_t ht_compare_and_set (hash_table_t *ht, const char *key_val, uint32_t key // Remove the value in associated with . Returns the value removed, or // DOES_NOT_EXIST if there was no value for that key. -uint64_t ht_remove (hash_table_t *ht, const char *key_val, uint32_t key_len) { - hash_table_i_t *hti = *ht; +uint64_t ht_remove (hashtable_t *ht, const char *key_val, uint32_t key_len) { + hashtable_i_t *hti = *ht; uint64_t val; uint32_t key_hash = murmur32(key_val, key_len); do { - val = hti_compare_and_set(hti, key_hash, key_val, key_len, HT_EXPECT_WHATEVER, TOMBSTONE); + val = hti_compare_and_set(hti, key_hash, key_val, key_len, EXPECT_WHATEVER, TOMBSTONE); if (val != COPIED_VALUE) return val == TOMBSTONE ? DOES_NOT_EXIST : val; assert(hti->next); @@ -519,8 +519,8 @@ uint64_t ht_remove (hash_table_t *ht, const char *key_val, uint32_t key_len) { } // Returns the number of key-values pairs in -uint64_t ht_count (hash_table_t *ht) { - hash_table_i_t *hti = *ht; +uint64_t ht_count (hashtable_t *ht) { + hashtable_i_t *hti = *ht; uint64_t count = 0; while (hti) { count += hti->count; @@ -530,15 +530,15 @@ uint64_t ht_count (hash_table_t *ht) { } // Allocate and initialize a new hash table. -hash_table_t *ht_alloc (void) { - hash_table_t *ht = nbd_malloc(sizeof(hash_table_t)); - *ht = (hash_table_i_t *)hti_alloc(ht, MIN_SCALE); +hashtable_t *ht_alloc (void) { + hashtable_t *ht = nbd_malloc(sizeof(hashtable_t)); + *ht = (hashtable_i_t *)hti_alloc(ht, MIN_SCALE); return ht; } // Free and its internal structures. -void ht_free (hash_table_t *ht) { - hash_table_i_t *hti = *ht; +void ht_free (hashtable_t *ht) { + hashtable_i_t *hti = *ht; do { for (uint32_t i = 0; i < (1 << hti->scale); ++i) { assert(hti->table[i].value == COPIED_VALUE || !IS_TAGGED(hti->table[i].value)); @@ -546,7 +546,7 @@ void ht_free (hash_table_t *ht) { nbd_free(GET_PTR(hti->table[i].key)); } } - hash_table_i_t *next = hti->next; + hashtable_i_t *next = hti->next; nbd_free(hti); hti = next; } while (hti);