X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvppinfra%2Fbihash_template.c;h=2b378427ce8c79e325d64ae700a0fff4e8e153f6;hb=a690fdbfe179e0ea65818c03b52535bf9210efd0;hp=d8b97b5f3d08b8319eaf12f2cf4ed426b7d6747e;hpb=8f544964a3df144a441b136c2a01427eca731eea;p=vpp.git diff --git a/src/vppinfra/bihash_template.c b/src/vppinfra/bihash_template.c index d8b97b5f3d0..2b378427ce8 100644 --- a/src/vppinfra/bihash_template.c +++ b/src/vppinfra/bihash_template.c @@ -15,31 +15,261 @@ /** @cond DOCUMENTATION_IS_IN_BIHASH_DOC_H */ +static inline void *BV (alloc_aligned) (BVT (clib_bihash) * h, uword nbytes) +{ + uword rv; + + /* Round to an even number of cache lines */ + nbytes += CLIB_CACHE_LINE_BYTES - 1; + nbytes &= ~(CLIB_CACHE_LINE_BYTES - 1); + + rv = alloc_arena_next (h); + alloc_arena_next (h) += nbytes; + + if (alloc_arena_next (h) > alloc_arena_size (h)) + os_out_of_memory (); + + return (void *) (uword) (rv + alloc_arena (h)); +} + +static void BV (clib_bihash_instantiate) (BVT (clib_bihash) * h) +{ + uword bucket_size; + + alloc_arena (h) = (uword) clib_mem_vm_alloc (h->memory_size); + alloc_arena_next (h) = 0; + alloc_arena_size (h) = h->memory_size; + + bucket_size = h->nbuckets * sizeof (h->buckets[0]); + h->buckets = BV (alloc_aligned) (h, bucket_size); + CLIB_MEMORY_BARRIER (); + h->instantiated = 1; +} + +void BV (clib_bihash_init2) (BVT (clib_bihash_init2_args) * a) +{ + int i; + void *oldheap; + BVT (clib_bihash) * h = a->h; + + a->nbuckets = 1 << (max_log2 (a->nbuckets)); + + h->name = (u8 *) a->name; + h->nbuckets = a->nbuckets; + h->log2_nbuckets = max_log2 (a->nbuckets); + h->memory_size = a->memory_size; + h->instantiated = 0; + h->fmt_fn = a->fmt_fn; + + alloc_arena (h) = 0; + + /* + * Make sure the requested size is rational. The max table + * size without playing the alignment card is 64 Gbytes. + * If someone starts complaining that's not enough, we can shift + * the offset by CLIB_LOG2_CACHE_LINE_BYTES... + */ + ASSERT (h->memory_size < (1ULL << BIHASH_BUCKET_OFFSET_BITS)); + + /* Add this hash table to the list */ + if (a->dont_add_to_all_bihash_list == 0) + { + for (i = 0; i < vec_len (clib_all_bihashes); i++) + if (clib_all_bihashes[i] == h) + goto do_lock; + oldheap = clib_all_bihash_set_heap (); + vec_add1 (clib_all_bihashes, (void *) h); + clib_mem_set_heap (oldheap); + } + +do_lock: + if (h->alloc_lock) + clib_mem_free ((void *) h->alloc_lock); + + /* + * Set up the lock now, so we can use it to make the first add + * thread-safe + */ + h->alloc_lock = clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES, + CLIB_CACHE_LINE_BYTES); + h->alloc_lock[0] = 0; + + if (a->instantiate_immediately) + BV (clib_bihash_instantiate) (h); +} + void BV (clib_bihash_init) (BVT (clib_bihash) * h, char *name, u32 nbuckets, uword memory_size) { - void *oldheap; + BVT (clib_bihash_init2_args) _a, *a = &_a; + + memset (a, 0, sizeof (*a)); + + a->h = h; + a->name = name; + a->nbuckets = nbuckets; + a->memory_size = memory_size; + + BV (clib_bihash_init2) (a); +} + +#if BIHASH_32_64_SVM +#if !defined (MFD_ALLOW_SEALING) +#define MFD_ALLOW_SEALING 0x0002U +#endif + +void BV (clib_bihash_master_init_svm) + (BVT (clib_bihash) * h, char *name, u32 nbuckets, u64 memory_size) +{ + uword bucket_size; + u8 *mmap_addr; + vec_header_t *freelist_vh; + int fd; + + ASSERT (memory_size < (1ULL << 32)); + /* Set up for memfd sharing */ + if ((fd = memfd_create (name, MFD_ALLOW_SEALING)) == -1) + { + clib_unix_warning ("memfd_create"); + return; + } + + if (ftruncate (fd, memory_size) < 0) + { + clib_unix_warning ("ftruncate"); + return; + } + + /* Not mission-critical, complain and continue */ + if ((fcntl (fd, F_ADD_SEALS, F_SEAL_SHRINK)) == -1) + clib_unix_warning ("fcntl (F_ADD_SEALS)"); + + mmap_addr = mmap (0, memory_size, + PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0 /* offset */ ); + + if (mmap_addr == MAP_FAILED) + { + clib_unix_warning ("mmap failed"); + ASSERT (0); + } + h->sh = (void *) mmap_addr; + h->memfd = fd; nbuckets = 1 << (max_log2 (nbuckets)); h->name = (u8 *) name; - h->nbuckets = nbuckets; + h->sh->nbuckets = h->nbuckets = nbuckets; h->log2_nbuckets = max_log2 (nbuckets); - h->mheap = mheap_alloc (0 /* use VM */ , memory_size); + alloc_arena (h) = (u64) (uword) mmap_addr; + alloc_arena_next (h) = CLIB_CACHE_LINE_BYTES; + alloc_arena_size (h) = memory_size; + + bucket_size = nbuckets * sizeof (h->buckets[0]); + h->buckets = BV (alloc_aligned) (h, bucket_size); + h->sh->buckets_as_u64 = (u64) BV (clib_bihash_get_offset) (h, h->buckets); + + h->alloc_lock = BV (alloc_aligned) (h, CLIB_CACHE_LINE_BYTES); + h->alloc_lock[0] = 0; + + h->sh->alloc_lock_as_u64 = + (u64) BV (clib_bihash_get_offset) (h, (void *) h->alloc_lock); + freelist_vh = + BV (alloc_aligned) (h, + sizeof (vec_header_t) + + BIHASH_FREELIST_LENGTH * sizeof (u64)); + freelist_vh->len = BIHASH_FREELIST_LENGTH; + h->sh->freelists_as_u64 = + (u64) BV (clib_bihash_get_offset) (h, freelist_vh->vector_data); + h->freelists = (void *) (freelist_vh->vector_data); + + h->fmt_fn = NULL; + h->instantiated = 1; +} + +void BV (clib_bihash_slave_init_svm) + (BVT (clib_bihash) * h, char *name, int fd) +{ + u8 *mmap_addr; + u64 memory_size; + BVT (clib_bihash_shared_header) * sh; + + /* Trial mapping, to learn the segment size */ + mmap_addr = mmap (0, 4096, PROT_READ, MAP_SHARED, fd, 0 /* offset */ ); + if (mmap_addr == MAP_FAILED) + { + clib_unix_warning ("trial mmap failed"); + ASSERT (0); + } + + sh = (BVT (clib_bihash_shared_header) *) mmap_addr; + + memory_size = sh->alloc_arena_size; + + munmap (mmap_addr, 4096); + + /* Actual mapping, at the required size */ + mmap_addr = mmap (0, memory_size, + PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0 /* offset */ ); - oldheap = clib_mem_set_heap (h->mheap); - vec_validate_aligned (h->buckets, nbuckets - 1, CLIB_CACHE_LINE_BYTES); - h->writer_lock = clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES, - CLIB_CACHE_LINE_BYTES); + if (mmap_addr == MAP_FAILED) + { + clib_unix_warning ("mmap failed"); + ASSERT (0); + } + + (void) close (fd); + + h->sh = (void *) mmap_addr; + alloc_arena (h) = (u64) (uword) mmap_addr; + h->memfd = -1; + + h->name = (u8 *) name; + h->buckets = BV (clib_bihash_get_value) (h, h->sh->buckets_as_u64); + h->nbuckets = h->sh->nbuckets; + h->log2_nbuckets = max_log2 (h->nbuckets); - clib_mem_set_heap (oldheap); + h->alloc_lock = BV (clib_bihash_get_value) (h, h->sh->alloc_lock_as_u64); + h->freelists = BV (clib_bihash_get_value) (h, h->sh->freelists_as_u64); + h->fmt_fn = NULL; +} +#endif /* BIHASH_32_64_SVM */ + +void BV (clib_bihash_set_kvp_format_fn) (BVT (clib_bihash) * h, + format_function_t * fmt_fn) +{ + h->fmt_fn = fmt_fn; } void BV (clib_bihash_free) (BVT (clib_bihash) * h) { - mheap_free (h->mheap); - memset (h, 0, sizeof (*h)); + int i; + + if (PREDICT_FALSE (h->instantiated == 0)) + goto never_initialized; + + h->instantiated = 0; + vec_free (h->working_copies); + vec_free (h->working_copy_lengths); +#if BIHASH_32_64_SVM == 0 + vec_free (h->freelists); +#else + if (h->memfd > 0) + (void) close (h->memfd); +#endif + clib_mem_vm_free ((void *) (uword) (alloc_arena (h)), alloc_arena_size (h)); +never_initialized: + clib_memset (h, 0, sizeof (*h)); + for (i = 0; i < vec_len (clib_all_bihashes); i++) + { + if ((void *) h == clib_all_bihashes[i]) + { + vec_delete (clib_all_bihashes, 1, i); + return; + } + } + clib_warning ("Couldn't find hash table %llx on clib_all_bihashes...", + (u64) (uword) h); } static @@ -47,62 +277,63 @@ BVT (clib_bihash_value) * BV (value_alloc) (BVT (clib_bihash) * h, u32 log2_pages) { BVT (clib_bihash_value) * rv = 0; - void *oldheap; - ASSERT (h->writer_lock[0]); + ASSERT (h->alloc_lock[0]); + +#if BIHASH_32_64_SVM + ASSERT (log2_pages < vec_len (h->freelists)); +#endif + if (log2_pages >= vec_len (h->freelists) || h->freelists[log2_pages] == 0) { - oldheap = clib_mem_set_heap (h->mheap); - - vec_validate (h->freelists, log2_pages); - vec_validate_aligned (rv, (1 << log2_pages) - 1, CLIB_CACHE_LINE_BYTES); - clib_mem_set_heap (oldheap); + vec_validate_init_empty (h->freelists, log2_pages, 0); + rv = BV (alloc_aligned) (h, (sizeof (*rv) * (1 << log2_pages))); goto initialize; } - rv = h->freelists[log2_pages]; - h->freelists[log2_pages] = rv->next_free; + rv = BV (clib_bihash_get_value) (h, (uword) h->freelists[log2_pages]); + h->freelists[log2_pages] = rv->next_free_as_u64; initialize: ASSERT (rv); - ASSERT (vec_len (rv) == (1 << log2_pages)); /* * Latest gcc complains that the length arg is zero * if we replace (1<writer_lock[0]); - - log2_pages = min_log2 (vec_len (v)); + ASSERT (h->alloc_lock[0]); ASSERT (vec_len (h->freelists) > log2_pages); - v->next_free = h->freelists[log2_pages]; - h->freelists[log2_pages] = v; + if (CLIB_DEBUG > 0) + clib_memset (v, 0xFE, sizeof (*v) * (1 << log2_pages)); + + v->next_free_as_u64 = (u64) h->freelists[log2_pages]; + h->freelists[log2_pages] = (u64) BV (clib_bihash_get_offset) (h, v); } static inline void -BV (make_working_copy) (BVT (clib_bihash) * h, clib_bihash_bucket_t * b) +BV (make_working_copy) (BVT (clib_bihash) * h, BVT (clib_bihash_bucket) * b) { BVT (clib_bihash_value) * v; - clib_bihash_bucket_t working_bucket __attribute__ ((aligned (8))); - void *oldheap; + BVT (clib_bihash_bucket) working_bucket __attribute__ ((aligned (8))); BVT (clib_bihash_value) * working_copy; - u32 cpu_number = os_get_cpu_number (); + u32 thread_index = os_get_thread_index (); + int log2_working_copy_length; + + ASSERT (h->alloc_lock[0]); - if (cpu_number >= vec_len (h->working_copies)) + if (thread_index >= vec_len (h->working_copies)) { - oldheap = clib_mem_set_heap (h->mheap); - vec_validate (h->working_copies, cpu_number); - clib_mem_set_heap (oldheap); + vec_validate (h->working_copies, thread_index); + vec_validate_init_empty (h->working_copy_lengths, thread_index, ~0); } /* @@ -110,44 +341,53 @@ BV (make_working_copy) (BVT (clib_bihash) * h, clib_bihash_bucket_t * b) * updates from multiple threads will not result in sporadic, spurious * lookup failures. */ - working_copy = h->working_copies[cpu_number]; + working_copy = h->working_copies[thread_index]; + log2_working_copy_length = h->working_copy_lengths[thread_index]; h->saved_bucket.as_u64 = b->as_u64; - oldheap = clib_mem_set_heap (h->mheap); - if ((1 << b->log2_pages) > vec_len (working_copy)) + if (b->log2_pages > log2_working_copy_length) { - vec_validate_aligned (working_copy, (1 << b->log2_pages) - 1, - sizeof (u64)); - h->working_copies[cpu_number] = working_copy; - } + /* + * It's not worth the bookkeeping to free working copies + * if (working_copy) + * clib_mem_free (working_copy); + */ + working_copy = BV (alloc_aligned) + (h, sizeof (working_copy[0]) * (1 << b->log2_pages)); + h->working_copy_lengths[thread_index] = b->log2_pages; + h->working_copies[thread_index] = working_copy; - _vec_len (working_copy) = 1 << b->log2_pages; - clib_mem_set_heap (oldheap); + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_working_copy_lost, + 1ULL << b->log2_pages); + } v = BV (clib_bihash_get_value) (h, b->offset); - clib_memcpy (working_copy, v, sizeof (*v) * (1 << b->log2_pages)); + clib_memcpy_fast (working_copy, v, sizeof (*v) * (1 << b->log2_pages)); working_bucket.as_u64 = b->as_u64; working_bucket.offset = BV (clib_bihash_get_offset) (h, working_copy); CLIB_MEMORY_BARRIER (); b->as_u64 = working_bucket.as_u64; - h->working_copies[cpu_number] = working_copy; + h->working_copies[thread_index] = working_copy; } static BVT (clib_bihash_value) * BV (split_and_rehash) (BVT (clib_bihash) * h, - BVT (clib_bihash_value) * old_values, u32 new_log2_pages) + BVT (clib_bihash_value) * old_values, u32 old_log2_pages, + u32 new_log2_pages) { BVT (clib_bihash_value) * new_values, *new_v; - int i, j, length; + int i, j, length_in_kvs; + + ASSERT (h->alloc_lock[0]); new_values = BV (value_alloc) (h, new_log2_pages); - length = vec_len (old_values) * BIHASH_KVP_PER_PAGE; + length_in_kvs = (1 << old_log2_pages) * BIHASH_KVP_PER_PAGE; - for (i = 0; i < length; i++) + for (i = 0; i < length_in_kvs; i++) { u64 new_hash; @@ -167,16 +407,17 @@ BV (split_and_rehash) /* Empty slot */ if (BV (clib_bihash_is_free) (&(new_v->kvp[j]))) { - clib_memcpy (&(new_v->kvp[j]), &(old_values->kvp[i]), - sizeof (new_v->kvp[j])); + clib_memcpy_fast (&(new_v->kvp[j]), &(old_values->kvp[i]), + sizeof (new_v->kvp[j])); goto doublebreak; } } /* Crap. Tell caller to try again */ - BV (value_free) (h, new_values); + BV (value_free) (h, new_values, new_log2_pages); return 0; doublebreak:; } + return new_values; } @@ -184,17 +425,21 @@ static BVT (clib_bihash_value) * BV (split_and_rehash_linear) (BVT (clib_bihash) * h, - BVT (clib_bihash_value) * old_values, u32 new_log2_pages) + BVT (clib_bihash_value) * old_values, u32 old_log2_pages, + u32 new_log2_pages) { BVT (clib_bihash_value) * new_values; - int i, j, new_length; + int i, j, new_length, old_length; + + ASSERT (h->alloc_lock[0]); new_values = BV (value_alloc) (h, new_log2_pages); new_length = (1 << new_log2_pages) * BIHASH_KVP_PER_PAGE; + old_length = (1 << old_log2_pages) * BIHASH_KVP_PER_PAGE; j = 0; /* Across the old value array */ - for (i = 0; i < vec_len (old_values) * BIHASH_KVP_PER_PAGE; i++) + for (i = 0; i < old_length; i++) { /* Find a free slot in the new linear scan bucket */ for (; j < new_length; j++) @@ -207,15 +452,15 @@ BV (split_and_rehash_linear) if (BV (clib_bihash_is_free) (&(new_values->kvp[j]))) { /* Copy the old value and move along */ - clib_memcpy (&(new_values->kvp[j]), &(old_values->kvp[i]), - sizeof (new_values->kvp[j])); + clib_memcpy_fast (&(new_values->kvp[j]), &(old_values->kvp[i]), + sizeof (new_values->kvp[j])); j++; goto doublebreak; } } /* This should never happen... */ clib_warning ("BUG: linear rehash failed!"); - BV (value_free) (h, new_values); + BV (value_free) (h, new_values, new_log2_pages); return 0; doublebreak:; @@ -223,20 +468,35 @@ BV (split_and_rehash_linear) return new_values; } -int BV (clib_bihash_add_del) - (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * add_v, int is_add) +static inline int BV (clib_bihash_add_del_inline) + (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * add_v, int is_add, + int (*is_stale_cb) (BVT (clib_bihash_kv) *, void *), void *arg) { u32 bucket_index; - clib_bihash_bucket_t *b, tmp_b; + BVT (clib_bihash_bucket) * b, tmp_b; BVT (clib_bihash_value) * v, *new_v, *save_new_v, *working_copy; - int rv = 0; int i, limit; u64 hash, new_hash; - u32 new_log2_pages; - u32 cpu_number = os_get_cpu_number (); + u32 new_log2_pages, old_log2_pages; + u32 thread_index = os_get_thread_index (); int mark_bucket_linear; int resplit_once; + /* + * Create the table (is_add=1,2), or flunk the request now (is_add=0) + * Use the alloc_lock to protect the instantiate operation. + */ + if (PREDICT_FALSE (h->instantiated == 0)) + { + if (is_add == 0) + return (-1); + + BV (clib_bihash_alloc_lock) (h); + if (h->instantiated == 0) + BV (clib_bihash_instantiate) (h); + BV (clib_bihash_alloc_unlock) (h); + } + hash = BV (clib_bihash_hash) (add_v); bucket_index = hash & (h->nbuckets - 1); @@ -244,105 +504,194 @@ int BV (clib_bihash_add_del) hash >>= h->log2_nbuckets; - while (__sync_lock_test_and_set (h->writer_lock, 1)) - ; + BV (clib_bihash_lock_bucket) (b); /* First elt in the bucket? */ - if (b->offset == 0) + if (BV (clib_bihash_bucket_is_empty) (b)) { if (is_add == 0) { - rv = -1; - goto unlock; + BV (clib_bihash_unlock_bucket) (b); + return (-1); } + BV (clib_bihash_alloc_lock) (h); v = BV (value_alloc) (h, 0); + BV (clib_bihash_alloc_unlock) (h); + *v->kvp = *add_v; - tmp_b.as_u64 = 0; + tmp_b.as_u64 = 0; /* clears bucket lock */ tmp_b.offset = BV (clib_bihash_get_offset) (h, v); + tmp_b.refcnt = 1; + CLIB_MEMORY_BARRIER (); - b->as_u64 = tmp_b.as_u64; - goto unlock; - } + b->as_u64 = tmp_b.as_u64; /* unlocks the bucket */ + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_alloc_add, 1); - BV (make_working_copy) (h, b); - - v = BV (clib_bihash_get_value) (h, h->saved_bucket.offset); + return (0); + } + /* WARNING: we're still looking at the live copy... */ limit = BIHASH_KVP_PER_PAGE; + v = BV (clib_bihash_get_value) (h, b->offset); + v += (b->linear_search == 0) ? hash & ((1 << b->log2_pages) - 1) : 0; if (b->linear_search) limit <<= b->log2_pages; if (is_add) { + /* + * Because reader threads are looking at live data, + * we have to be extra careful. Readers do NOT hold the + * bucket lock. We need to be SLOWER than a search, past the + * point where readers CHECK the bucket lock. + */ + /* * For obvious (in hindsight) reasons, see if we're supposed to * replace an existing key, then look for an empty slot. */ for (i = 0; i < limit; i++) { - if (!memcmp (&(v->kvp[i]), &add_v->key, sizeof (add_v->key))) + if (BV (clib_bihash_key_compare) (v->kvp[i].key, add_v->key)) { - clib_memcpy (&(v->kvp[i]), add_v, sizeof (*add_v)); - CLIB_MEMORY_BARRIER (); - /* Restore the previous (k,v) pairs */ - b->as_u64 = h->saved_bucket.as_u64; - goto unlock; + /* Add but do not overwrite? */ + if (is_add == 2) + { + BV (clib_bihash_unlock_bucket) (b); + return (-2); + } + + CLIB_MEMORY_BARRIER (); /* Add a delay */ + clib_memcpy_fast (&(v->kvp[i]), add_v, sizeof (*add_v)); + BV (clib_bihash_unlock_bucket) (b); + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_replace, 1); + return (0); } } + /* + * Look for an empty slot. If found, use it + */ for (i = 0; i < limit; i++) { if (BV (clib_bihash_is_free) (&(v->kvp[i]))) { - clib_memcpy (&(v->kvp[i]), add_v, sizeof (*add_v)); - CLIB_MEMORY_BARRIER (); - b->as_u64 = h->saved_bucket.as_u64; - goto unlock; + /* + * Copy the value first, so that if a reader manages + * to match the new key, the value will be right... + */ + clib_memcpy_fast (&(v->kvp[i].value), + &add_v->value, sizeof (add_v->value)); + CLIB_MEMORY_BARRIER (); /* Make sure the value has settled */ + clib_memcpy_fast (&(v->kvp[i]), &add_v->key, + sizeof (add_v->key)); + b->refcnt++; + ASSERT (b->refcnt > 0); + BV (clib_bihash_unlock_bucket) (b); + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_add, 1); + return (0); + } + } + /* look for stale data to overwrite */ + if (is_stale_cb) + { + for (i = 0; i < limit; i++) + { + if (is_stale_cb (&(v->kvp[i]), arg)) + { + CLIB_MEMORY_BARRIER (); + clib_memcpy_fast (&(v->kvp[i]), add_v, sizeof (*add_v)); + BV (clib_bihash_unlock_bucket) (b); + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_replace, 1); + return (0); + } } } - /* no room at the inn... split case... */ + /* Out of space in this bucket, split the bucket... */ } - else + else /* delete case */ { for (i = 0; i < limit; i++) { - if (!memcmp (&(v->kvp[i]), &add_v->key, sizeof (add_v->key))) + /* Found the key? Kill it... */ + if (BV (clib_bihash_key_compare) (v->kvp[i].key, add_v->key)) { - memset (&(v->kvp[i]), 0xff, sizeof (*(add_v))); - CLIB_MEMORY_BARRIER (); - b->as_u64 = h->saved_bucket.as_u64; - goto unlock; + clib_memset (&(v->kvp[i]), 0xff, sizeof (*(add_v))); + /* Is the bucket empty? */ + if (PREDICT_TRUE (b->refcnt > 1)) + { + b->refcnt--; + BV (clib_bihash_unlock_bucket) (b); + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_del, 1); + return (0); + } + else /* yes, free it */ + { + /* Save old bucket value, need log2_pages to free it */ + tmp_b.as_u64 = b->as_u64; + CLIB_MEMORY_BARRIER (); + + /* Kill and unlock the bucket */ + b->as_u64 = 0; + + /* And free the backing storage */ + BV (clib_bihash_alloc_lock) (h); + /* Note: v currently points into the middle of the bucket */ + v = BV (clib_bihash_get_value) (h, tmp_b.offset); + BV (value_free) (h, v, tmp_b.log2_pages); + BV (clib_bihash_alloc_unlock) (h); + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_del_free, + 1); + return (0); + } } } - rv = -3; - b->as_u64 = h->saved_bucket.as_u64; - goto unlock; + /* Not found... */ + BV (clib_bihash_unlock_bucket) (b); + return (-3); } - new_log2_pages = h->saved_bucket.log2_pages + 1; + /* Move readers to a (locked) temp copy of the bucket */ + BV (clib_bihash_alloc_lock) (h); + BV (make_working_copy) (h, b); + + v = BV (clib_bihash_get_value) (h, h->saved_bucket.offset); + + old_log2_pages = h->saved_bucket.log2_pages; + new_log2_pages = old_log2_pages + 1; mark_bucket_linear = 0; + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_split_add, 1); + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_splits, old_log2_pages); - working_copy = h->working_copies[cpu_number]; + working_copy = h->working_copies[thread_index]; resplit_once = 0; + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_splits, 1); - new_v = BV (split_and_rehash) (h, working_copy, new_log2_pages); + new_v = BV (split_and_rehash) (h, working_copy, old_log2_pages, + new_log2_pages); if (new_v == 0) { try_resplit: resplit_once = 1; new_log2_pages++; /* Try re-splitting. If that fails, fall back to linear search */ - new_v = BV (split_and_rehash) (h, working_copy, new_log2_pages); + new_v = BV (split_and_rehash) (h, working_copy, old_log2_pages, + new_log2_pages); if (new_v == 0) { mark_linear: new_log2_pages--; /* pinned collisions, use linear search */ new_v = - BV (split_and_rehash_linear) (h, working_copy, new_log2_pages); + BV (split_and_rehash_linear) (h, working_copy, old_log2_pages, + new_log2_pages); mark_bucket_linear = 1; + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_linear, 1); } + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_resplit, 1); + BV (clib_bihash_increment_stat) (h, BIHASH_STAT_splits, + old_log2_pages + 1); } /* Try to add the new entry */ @@ -359,12 +708,13 @@ int BV (clib_bihash_add_del) { if (BV (clib_bihash_is_free) (&(new_v->kvp[i]))) { - clib_memcpy (&(new_v->kvp[i]), add_v, sizeof (*add_v)); + clib_memcpy_fast (&(new_v->kvp[i]), add_v, sizeof (*add_v)); goto expand_ok; } } + /* Crap. Try again */ - BV (value_free) (h, save_new_v); + BV (value_free) (h, save_new_v, new_log2_pages); /* * If we've already doubled the size of the bucket once, * fall back to linear search now. @@ -375,44 +725,64 @@ int BV (clib_bihash_add_del) goto try_resplit; expand_ok: - /* Keep track of the number of linear-scan buckets */ - if (tmp_b.linear_search ^ mark_bucket_linear) - h->linear_buckets += (mark_bucket_linear == 1) ? 1 : -1; - tmp_b.log2_pages = new_log2_pages; tmp_b.offset = BV (clib_bihash_get_offset) (h, save_new_v); tmp_b.linear_search = mark_bucket_linear; + tmp_b.refcnt = h->saved_bucket.refcnt + 1; + ASSERT (tmp_b.refcnt > 0); + tmp_b.lock = 0; CLIB_MEMORY_BARRIER (); b->as_u64 = tmp_b.as_u64; + /* free the old bucket */ v = BV (clib_bihash_get_value) (h, h->saved_bucket.offset); - BV (value_free) (h, v); + BV (value_free) (h, v, h->saved_bucket.log2_pages); + BV (clib_bihash_alloc_unlock) (h); + return (0); +} -unlock: - CLIB_MEMORY_BARRIER (); - h->writer_lock[0] = 0; - return rv; +int BV (clib_bihash_add_del) + (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * add_v, int is_add) +{ + return BV (clib_bihash_add_del_inline) (h, add_v, is_add, 0, 0); +} + +int BV (clib_bihash_add_or_overwrite_stale) + (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * add_v, + int (*stale_callback) (BVT (clib_bihash_kv) *, void *), void *arg) +{ + return BV (clib_bihash_add_del_inline) (h, add_v, 1, stale_callback, arg); } int BV (clib_bihash_search) - (const BVT (clib_bihash) * h, + (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * search_key, BVT (clib_bihash_kv) * valuep) { u64 hash; u32 bucket_index; BVT (clib_bihash_value) * v; - clib_bihash_bucket_t *b; + BVT (clib_bihash_bucket) * b; int i, limit; ASSERT (valuep); + if (PREDICT_FALSE (alloc_arena (h) == 0)) + return -1; + hash = BV (clib_bihash_hash) (search_key); bucket_index = hash & (h->nbuckets - 1); b = &h->buckets[bucket_index]; - if (b->offset == 0) + if (BV (clib_bihash_bucket_is_empty) (b)) return -1; + if (PREDICT_FALSE (b->lock)) + { + volatile BVT (clib_bihash_bucket) * bv = b; + while (bv->lock) + CLIB_PAUSE (); + } + hash >>= h->log2_nbuckets; v = BV (clib_bihash_get_value) (h, b->offset); @@ -436,26 +806,37 @@ u8 *BV (format_bihash) (u8 * s, va_list * args) { BVT (clib_bihash) * h = va_arg (*args, BVT (clib_bihash) *); int verbose = va_arg (*args, int); - clib_bihash_bucket_t *b; + BVT (clib_bihash_bucket) * b; BVT (clib_bihash_value) * v; int i, j, k; u64 active_elements = 0; + u64 active_buckets = 0; + u64 linear_buckets = 0; + u64 used_bytes; s = format (s, "Hash table %s\n", h->name ? h->name : (u8 *) "(unnamed)"); + if (PREDICT_FALSE (alloc_arena (h) == 0)) + return format (s, "[empty, uninitialized]"); + for (i = 0; i < h->nbuckets; i++) { b = &h->buckets[i]; - if (b->offset == 0) + if (BV (clib_bihash_bucket_is_empty) (b)) { if (verbose > 1) s = format (s, "[%d]: empty\n", i); continue; } + active_buckets++; + + if (b->linear_search) + linear_buckets++; + if (verbose) { - s = format (s, "[%d]: heap offset %d, len %d, linear %d\n", i, + s = format (s, "[%d]: heap offset %lld, len %d, linear %d\n", i, b->offset, (1 << b->log2_pages), b->linear_search); } @@ -473,9 +854,18 @@ u8 *BV (format_bihash) (u8 * s, va_list * args) } if (verbose) { - s = format (s, " %d: %U\n", - j * BIHASH_KVP_PER_PAGE + k, - BV (format_bihash_kvp), &(v->kvp[k])); + if (h->fmt_fn) + { + s = format (s, " %d: %U\n", + j * BIHASH_KVP_PER_PAGE + k, + h->fmt_fn, &(v->kvp[k]), verbose); + } + else + { + s = format (s, " %d: %U\n", + j * BIHASH_KVP_PER_PAGE + k, + BV (format_bihash_kvp), &(v->kvp[k])); + } } active_elements++; } @@ -483,25 +873,53 @@ u8 *BV (format_bihash) (u8 * s, va_list * args) } } - s = format (s, " %lld active elements\n", active_elements); + s = format (s, " %lld active elements %lld active buckets\n", + active_elements, active_buckets); s = format (s, " %d free lists\n", vec_len (h->freelists)); - s = format (s, " %d linear search buckets\n", h->linear_buckets); + for (i = 0; i < vec_len (h->freelists); i++) + { + u32 nfree = 0; + BVT (clib_bihash_value) * free_elt; + u64 free_elt_as_u64 = h->freelists[i]; + + while (free_elt_as_u64) + { + free_elt = BV (clib_bihash_get_value) (h, free_elt_as_u64); + nfree++; + free_elt_as_u64 = free_elt->next_free_as_u64; + } + + if (nfree || verbose) + s = format (s, " [len %d] %u free elts\n", 1 << i, nfree); + } + + s = format (s, " %lld linear search buckets\n", linear_buckets); + used_bytes = alloc_arena_next (h); + s = format (s, + " arena: base %llx, next %llx\n" + " used %lld b (%lld Mbytes) of %lld b (%lld Mbytes)\n", + alloc_arena (h), alloc_arena_next (h), + used_bytes, used_bytes >> 20, + alloc_arena_size (h), alloc_arena_size (h) >> 20); return s; } void BV (clib_bihash_foreach_key_value_pair) - (BVT (clib_bihash) * h, void *callback, void *arg) + (BVT (clib_bihash) * h, + BV (clib_bihash_foreach_key_value_pair_cb) cb, void *arg) { int i, j, k; - clib_bihash_bucket_t *b; + BVT (clib_bihash_bucket) * b; BVT (clib_bihash_value) * v; - void (*fp) (BVT (clib_bihash_kv) *, void *) = callback; + + if (PREDICT_FALSE (alloc_arena (h) == 0)) + return; for (i = 0; i < h->nbuckets; i++) { b = &h->buckets[i]; - if (b->offset == 0) + if (BV (clib_bihash_bucket_is_empty) (b)) continue; v = BV (clib_bihash_get_value) (h, b->offset); @@ -512,10 +930,18 @@ void BV (clib_bihash_foreach_key_value_pair) if (BV (clib_bihash_is_free) (&v->kvp[k])) continue; - (*fp) (&v->kvp[k], arg); + if (BIHASH_WALK_STOP == cb (&v->kvp[k], arg)) + return; + /* + * In case the callback deletes the last entry in the bucket... + */ + if (BV (clib_bihash_bucket_is_empty) (b)) + goto doublebreak; } v++; } + doublebreak: + ; } }