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1032bf2543
The spinlocked hash has a main rw spinlock for the data blocks and then a rw spinlock for each hash chain. Rehashing is asynchronous, running from an event, and it happens chain-wise, never blocking more than one chain at a time.
522 lines
15 KiB
C
522 lines
15 KiB
C
/*
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* BIRD Library -- Generic Hash Table
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*
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* (c) 2013 Ondrej Zajicek <santiago@crfreenet.org>
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* (c) 2024 Maria Matejka <mq@jmq.cz>
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* (c) 2013--2024 CZ.NIC z.s.p.o.
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*
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* Can be freely distributed and used under the terms of the GNU GPL.
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*/
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#ifndef _BIRD_HASH_H_
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#define _BIRD_HASH_H_
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/*
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* Regular hash table
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*/
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#define HASH(type) struct { type **data; uint count; u8 order; }
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#define HASH_TYPE(v) typeof(** (v).data)
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#define HASH_SIZE(v) (1U << (v).order)
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#define HASH_EQ(v,id,k1,k2...) (id##_EQ(k1, k2))
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#define HASH_FN(v,id,key...) ((u32) (id##_FN(key)) >> (32 - (v).order))
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#define HASH_FNO(id,key...) id##_FN(key)
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#define HASH_INIT(v,pool,init_order) \
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({ \
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(v).count = 0; \
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(v).order = (init_order); \
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(v).data = mb_allocz(pool, HASH_SIZE(v) * sizeof(* (v).data)); \
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})
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#define HASH_FREE(v) \
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({ \
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mb_free((v).data); \
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(v) = (typeof(v)){ }; \
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})
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#define HASH_FIND_CHAIN(v,id,key...) \
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({ \
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u32 _h = HASH_FN(v, id, key); \
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(v).data[_h]; \
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})
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#define HASH_FIND(v,id,key...) \
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({ \
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HASH_TYPE(v) *_n = HASH_FIND_CHAIN(v, id, key); \
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while (_n && !HASH_EQ(v, id, id##_KEY(_n), key)) \
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_n = id##_NEXT(_n); \
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_n; \
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})
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#define HASH_INSERT(v,id,node) \
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({ \
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u32 _h = HASH_FN(v, id, id##_KEY((node))); \
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HASH_TYPE(v) **_nn = (v).data + _h; \
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id##_NEXT(node) = *_nn; \
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*_nn = node; \
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(v).count++; \
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})
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#define HASH_DO_REMOVE(v,id,_nn) \
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({ \
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*_nn = id##_NEXT((*_nn)); \
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(v).count--; \
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})
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#define HASH_DELETE(v,id,key...) \
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({ \
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u32 _h = HASH_FN(v, id, key); \
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HASH_TYPE(v) *_n, **_nn = (v).data + _h; \
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\
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while ((*_nn) && !HASH_EQ(v, id, id##_KEY((*_nn)), key)) \
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_nn = &(id##_NEXT((*_nn))); \
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\
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if (_n = *_nn) \
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HASH_DO_REMOVE(v,id,_nn); \
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_n; \
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})
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#define HASH_REMOVE(v,id,node) \
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({ \
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u32 _h = HASH_FN(v, id, id##_KEY((node))); \
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HASH_TYPE(v) *_n, **_nn = (v).data + _h; \
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\
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while ((*_nn) && (*_nn != (node))) \
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_nn = &(id##_NEXT((*_nn))); \
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\
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if (_n = *_nn) \
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HASH_DO_REMOVE(v,id,_nn); \
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_n; \
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})
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#define HASH_REHASH(v,id,pool,step) \
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({ \
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HASH_TYPE(v) *_n, *_n2, **_od; \
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uint _i, _os; \
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\
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_os = HASH_SIZE(v); \
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_od = (v).data; \
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(v).count = 0; \
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(v).order += (step); \
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(v).data = mb_allocz(pool, HASH_SIZE(v) * sizeof(* (v).data)); \
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\
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for (_i = 0; _i < _os; _i++) \
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for (_n = _od[_i]; _n && (_n2 = id##_NEXT(_n), 1); _n = _n2) \
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HASH_INSERT(v, id, _n); \
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\
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mb_free(_od); \
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})
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#define REHASH_LO_MARK(a,b,c,d,e,f) a
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#define REHASH_HI_MARK(a,b,c,d,e,f) b
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#define REHASH_LO_STEP(a,b,c,d,e,f) c
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#define REHASH_HI_STEP(a,b,c,d,e,f) d
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#define REHASH_LO_BOUND(a,b,c,d,e,f) e
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#define REHASH_HI_BOUND(a,b,c,d,e,f) f
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#define HASH_DEFINE_REHASH_FN(id,type) \
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static void id##_REHASH(void *v, pool *p, int step) \
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{ HASH_REHASH(* (HASH(type) *) v, id, p, step); }
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#define HASH_MAY_STEP_UP(v,id,pool) HASH_MAY_STEP_UP_(v,pool, id##_REHASH, id##_PARAMS)
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#define HASH_MAY_STEP_DOWN(v,id,pool) HASH_MAY_STEP_DOWN_(v,pool, id##_REHASH, id##_PARAMS)
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#define HASH_MAY_RESIZE_DOWN(v,id,pool) HASH_MAY_RESIZE_DOWN_(v,pool, id##_REHASH, id##_PARAMS)
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#define HASH_MAY_STEP_UP_(v,pool,rehash_fn,args) \
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({ \
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if (((v).count > (HASH_SIZE(v) REHASH_HI_MARK(args))) && \
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((v).order < (REHASH_HI_BOUND(args)))) \
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rehash_fn(&(v), pool, REHASH_HI_STEP(args)); \
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})
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#define HASH_MAY_STEP_DOWN_(v,pool,rehash_fn,args) \
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({ \
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if (((v).count < (HASH_SIZE(v) REHASH_LO_MARK(args))) && \
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((v).order > (REHASH_LO_BOUND(args)))) \
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rehash_fn(&(v), pool, -(REHASH_LO_STEP(args))); \
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})
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#define HASH_MAY_RESIZE_DOWN_(v,pool,rehash_fn,args) \
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({ \
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{ \
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uint _o = (v).order; \
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while (((v).count < ((1U << _o) REHASH_LO_MARK(args))) && \
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(_o > (REHASH_LO_BOUND(args)))) \
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_o -= (REHASH_LO_STEP(args)); \
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if (_o < (v).order) \
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rehash_fn(&(v), pool, _o - (v).order); \
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} \
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})
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#define HASH_INSERT2(v,id,pool,node) \
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({ \
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HASH_INSERT(v, id, node); \
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HASH_MAY_STEP_UP(v, id, pool); \
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})
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#define HASH_DELETE2(v,id,pool,key...) \
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({ \
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HASH_TYPE(v) *_n = HASH_DELETE(v, id, key); \
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if (_n) HASH_MAY_STEP_DOWN(v, id, pool); \
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_n; \
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})
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#define HASH_REMOVE2(v,id,pool,node) \
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({ \
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HASH_TYPE(v) *_n = HASH_REMOVE(v, id, node); \
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if (_n) HASH_MAY_STEP_DOWN(v, id, pool); \
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_n; \
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})
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#define HASH_WALK(v,next,n) \
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do { \
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HASH_TYPE(v) *n; \
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uint _i; \
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uint _s = HASH_SIZE(v); \
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for (_i = 0; _i < _s; _i++) \
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for (n = (v).data[_i]; n; n = n->next)
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#define HASH_WALK_END } while (0)
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#define HASH_WALK_DELSAFE(v,next,n) \
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do { \
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HASH_TYPE(v) *n, *_next; \
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uint _i; \
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uint _s = HASH_SIZE(v); \
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for (_i = 0; _i < _s; _i++) \
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for (n = (v).data[_i]; n && (_next = n->next, 1); n = _next)
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#define HASH_WALK_DELSAFE_END } while (0)
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#define HASH_WALK_FILTER(v,next,n,nn) \
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do { \
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HASH_TYPE(v) *n, **nn; \
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uint _i; \
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uint _s = HASH_SIZE(v); \
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for (_i = 0; _i < _s; _i++) \
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for (nn = (v).data + _i; n = *nn; (*nn == n) ? (nn = &n->next) : NULL)
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#define HASH_WALK_FILTER_END } while (0)
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/*
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* Atomic hash table with data-local spinlocks
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*/
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#define SPINHASH(type) \
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struct { \
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_Atomic uint count; \
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rw_spinlock lock; \
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uint cur_order, new_order; \
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struct { type *data; rw_spinlock lock; } *cur, *new; \
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pool *pool; \
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event rehash; \
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event_list *target; \
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}
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#define SPINHASH_INIT(v,id,_pool,_target) \
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({ \
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atomic_store_explicit(&(v).count, 0, memory_order_relaxed); \
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(v).cur_order = id##_ORDER; \
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(v).new_order = 0; \
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(v).cur = mb_allocz(_pool, (1U << id##_ORDER) * sizeof *(v).cur); \
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(v).new = NULL; \
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(v).pool = _pool; \
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(v).rehash = (event) { .hook = id##_REHASH, .data = &(v), }; \
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(v).target = _target; \
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})
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#define SPINHASH_FREE(v) \
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({ \
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ev_postpone(&(v).rehash); \
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mb_free((v).cur); \
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ASSERT_DIE((v).new == NULL); \
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(v).cur = NULL; \
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(v).cur_order = 0; \
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(v).pool = NULL; \
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(v).target = NULL; \
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})
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#define SPINHASH_BEGIN_CHAIN(v,id,rw,n,key...) \
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do { \
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typeof (&v) _v = &(v); \
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rws_read_lock(&_v->lock); \
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u32 _hh = id##_FN(key); \
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SPINHASH_BEGIN_CHAIN_INDEX(v,_hh,rw,n); \
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#define SPINHASH_BEGIN_CHAIN_INDEX(v,h,rw,n) \
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u32 _ch = (h) >> (32 - (v).cur_order); \
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rw_spinlock *_lock = &(v).cur[_ch].lock; \
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rws_##rw##_lock(_lock); \
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typeof (&(v).cur[_ch].data) n = &(v).cur[_ch].data; \
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if (*n == SPINHASH_REHASH_SENTINEL) { \
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rws_##rw##_unlock(_lock); \
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u32 _nh = (h) >> (32 - (v).new_order); \
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_lock = &(v).new[_nh].lock; \
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rws_##rw##_lock(_lock); \
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n = &(v).new[_nh].data; \
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ASSERT_DIE(*n != SPINHASH_REHASH_SENTINEL); \
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};
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#define SPINHASH_END_CHAIN_INDEX(rw) \
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rws_##rw##_unlock(_lock); \
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#define SPINHASH_END_CHAIN(rw) \
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SPINHASH_END_CHAIN_INDEX(rw); \
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rws_read_unlock(&_v->lock); \
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} while (0)
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#define SPINHASH_FIND(v,id,key...) \
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({ \
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typeof ((v).cur[0].data) _n; \
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SPINHASH_BEGIN_CHAIN(v,id,read,_c,key); \
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while ((*_c) && !HASH_EQ(v,id,id##_KEY((*_c)), key)) \
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_c = &id##_NEXT((*_c)); \
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_n = *_c; \
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SPINHASH_END_CHAIN(read); \
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_n; \
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})
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#define SPINHASH_INSERT(v,id,n) \
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do { \
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rws_read_lock(&(v).lock); \
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uint _h = HASH_FNO(id, id##_KEY(n)); \
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uint _ch = _h >> (32 - (v).cur_order); \
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rws_write_lock(&(v).cur[_ch].lock); \
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if ((v).cur[_ch].data == SPINHASH_REHASH_SENTINEL) { \
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uint _nh = _h >> (32 - (v).new_order); \
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rws_write_lock(&(v).new[_nh].lock); \
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ASSERT_DIE((v).new[_nh].data != SPINHASH_REHASH_SENTINEL); \
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id##_NEXT(n) = (v).new[_nh].data; \
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(v).new[_nh].data = n; \
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rws_write_unlock(&(v).new[_nh].lock); \
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} else { \
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id##_NEXT(n) = (v).cur[_ch].data; \
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(v).cur[_ch].data = n; \
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} \
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rws_write_unlock(&(v).cur[_ch].lock); \
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uint count = atomic_fetch_add_explicit(&(v).count, 1, memory_order_relaxed);\
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SPINHASH_REQUEST_REHASH(v,id,count); \
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rws_read_unlock(&(v).lock); \
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} while (0) \
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#define SPINHASH_REMOVE(v,id,n) \
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do { \
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typeof(n) _n = (n); \
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SPINHASH_BEGIN_CHAIN(v,id,write,_c,id##_KEY(_n)) \
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for (; *_c; _c = &id##_NEXT((*_c))) \
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if (_n == *_c) { \
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SPINHASH_DO_REMOVE(v,id,_c); \
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break; \
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} \
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SPINHASH_END_CHAIN(write); \
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uint count = atomic_load_explicit(&(v).count, memory_order_relaxed);\
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SPINHASH_REQUEST_REHASH(v,id,count); \
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} while (0)
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#define SPINHASH_DO_REMOVE(v,id,c) \
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atomic_fetch_sub_explicit(&(v).count, 1, memory_order_relaxed); \
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*c = id##_NEXT((*c)); \
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#define SPINHASH_WALK(v,id,n) \
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SPINHASH_WALK_CHAINS(v,id,read,nn) \
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for (typeof (*nn) n = *nn; n; n = id##_NEXT(n)) { \
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#define SPINHASH_WALK_END \
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} \
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SPINHASH_WALK_CHAINS_END(read) \
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#define SPINHASH_WALK_FILTER(v,id,rw,nn) \
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SPINHASH_WALK_CHAINS(v,id,rw,nn) \
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for (; nn && *nn; nn = nn ? &id##_NEXT((*nn)) : NULL)
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#define SPINHASH_WALK_FILTER_END(rw) SPINHASH_WALK_CHAINS_END(rw)
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#define SPINHASH_WALK_CHAINS(v,id,rw,nn) \
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do { \
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typeof (&v) _v = &(v); \
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rws_read_lock(&_v->lock); \
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for (uint _h = 0; !(_h >> _v->cur_order); _h++) { \
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SPINHASH_BEGIN_CHAIN_INDEX(v,_h,rw,nn); \
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#define SPINHASH_WALK_CHAINS_END(rw) \
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SPINHASH_END_CHAIN_INDEX(rw); \
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} \
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rws_read_unlock(&_v->lock); \
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} while (0)
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#define SPINHASH_CHECK_REHASH(v,id,count) SPINHASH_CHECK_REHASH_(v,id,count,id##_PARAMS)
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#define SPINHASH_CHECK_REHASH_(v,id,count,args) \
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({ \
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uint order = (v).new_order ?: (v).cur_order; \
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uint size = 1U << order; \
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((count > size REHASH_HI_MARK(args)) && (order < REHASH_HI_BOUND(args))) ? \
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REHASH_HI_STEP(args) : \
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((count < size REHASH_LO_MARK(args)) && (order > REHASH_LO_BOUND(args))) ? \
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-REHASH_LO_STEP(args) : \
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0; \
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})
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#define SPINHASH_REQUEST_REHASH(v,id,count) \
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if (SPINHASH_CHECK_REHASH(v,id,count) && (v).target) \
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ev_send((v).target, &(v).rehash);
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#define SPINHASH_DEFINE_REHASH_FN(id,type) \
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static void id##_REHASH(void *_v) { \
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SPINHASH(type) *v = _v; \
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SPINHASH_REHASH_FN_BODY(v,id,type); \
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}
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#define SPINHASH_REHASH_FN_BODY(v,id,type) \
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int step; \
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SPINHASH_REHASH_PREPARE(v,id,type,step); \
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if (step) { \
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if (step > 0) SPINHASH_REHASH_UP(id,type,step); \
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if (step < 0) SPINHASH_REHASH_DOWN(id,type,-step); \
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SPINHASH_REHASH_FINISH(v,id); \
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} \
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#define SPINHASH_REHASH_PREPARE(v,id,type,step) \
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rws_write_lock(&(v)->lock); \
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ASSERT_DIE((v)->new_order == 0); \
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uint _cb = atomic_load_explicit(&(v)->count, memory_order_relaxed); \
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step = SPINHASH_CHECK_REHASH((*(v)),id,_cb); \
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if (step) { \
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(v)->new_order = (v)->cur_order + step; \
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uint nsz = 1U << (v)->new_order; \
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(v)->new = mb_alloc((v)->pool, nsz * sizeof *(v)->new); \
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for (uint i=0; i<nsz; i++) { \
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(v)->new[i].data = SPINHASH_REHASH_SENTINEL; \
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(v)->new[i].lock = (rw_spinlock) {}; \
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} \
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} \
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rws_write_unlock(&(v)->lock); \
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#define SPINHASH_REHASH_FINISH(v,id) \
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ASSERT_DIE(step); \
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rws_write_lock(&(v)->lock); \
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(v)->cur = (v)->new; (v)->cur_order = (v)->new_order; \
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(v)->new = NULL; (v)->new_order = 0; \
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uint _ce = atomic_load_explicit(&(v)->count, memory_order_relaxed); \
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SPINHASH_REQUEST_REHASH(*(v),id,_ce) \
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rws_write_unlock(&(v)->lock); \
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mb_free((v)->new); \
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#define SPINHASH_REHASH_UP(v,id,type,step) \
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for (uint i=0; !(i >> (v)->cur_order); i++) { \
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rws_write_lock(&(v)->cur[i].lock); \
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for (uint p=0; !(p >> step); p++) { \
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uint ppos = (i << step) | p; \
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rws_write_lock(&(v)->new[ppos].lock); \
|
|
ASSERT_DIE((v)->new[ppos].data == SPINHASH_REHASH_SENTINEL); \
|
|
(v)->new[ppos].data = NULL; \
|
|
} \
|
|
for (type *n; n = (v)->cur[i].data; ) { \
|
|
(v)->cur[i].data = id##_NEXT(n); \
|
|
uint _h = HASH_FNO(id, id##_KEY(n)); \
|
|
ASSERT_DIE((_h >> (32 - (v)->cur_order)) == i); \
|
|
uint _nh = _h >> (32 - (v)->new_order); \
|
|
id##_NEXT(n) = (v)->new[_nh].data; \
|
|
(v)->new[_nh].data = n; \
|
|
} \
|
|
(v)->cur[i].data = SPINHASH_REHASH_SENTINEL; \
|
|
for (uint p=0; !(p >> step); p++) \
|
|
rws_write_unlock(&(v)->new[((i+1) << step) - p - 1].lock); \
|
|
rws_write_unlock(&(v)->cur[i].lock); \
|
|
} \
|
|
|
|
#define SPINHASH_REHASH_DOWN(v,id,type,step) \
|
|
for (uint i=0; !(i >> (v)->cur_order); i++) { \
|
|
uint p = i >> step; \
|
|
rws_write_lock(&(v)->cur[i].lock); \
|
|
rws_write_lock(&(v)->new[p].lock); \
|
|
if (i == (p << step)) { \
|
|
ASSERT_DIE((v)->new[p].data == SPINHASH_REHASH_SENTINEL); \
|
|
(v)->new[p].data = NULL; \
|
|
} else \
|
|
ASSERT_DIE((v)->new[p].data != SPINHASH_REHASH_SENTINEL); \
|
|
for (type *n; n = (v)->cur[i].data; ) { \
|
|
(v)->cur[i].data = id##_NEXT(n); \
|
|
id##_NEXT(n) = (v)->new[p].data; \
|
|
(v)->new[p].data = n; \
|
|
} \
|
|
(v)->cur[i].data = SPINHASH_REHASH_SENTINEL; \
|
|
rws_write_unlock(&(v)->new[p].lock); \
|
|
rws_write_unlock(&(v)->cur[i].lock); \
|
|
}
|
|
|
|
|
|
#define SPINHASH_REHASH_SENTINEL ((void *) 1)
|
|
|
|
|
|
/*
|
|
* Memory hashing functions
|
|
*/
|
|
|
|
static inline void
|
|
mem_hash_init(u64 *h)
|
|
{
|
|
*h = 0x001047d54778bcafULL;
|
|
}
|
|
|
|
static inline void
|
|
mem_hash_mix(u64 *h, const void *p, uint s)
|
|
{
|
|
const u64 multiplier = 0xb38bc09a61202731ULL;
|
|
const char *pp = p;
|
|
uint i;
|
|
|
|
for (i=0; i<s/4; i++)
|
|
*h = *h * multiplier + ((const u32 *)pp)[i];
|
|
|
|
for (i=s & ~0x3; i<s; i++)
|
|
*h = *h * multiplier + pp[i];
|
|
}
|
|
|
|
static inline void
|
|
mem_hash_mix_str(u64 *h, const char *s)
|
|
{
|
|
const u64 multiplier = 0xb38bc09a61202731ULL;
|
|
while (s)
|
|
*h = *h * multiplier + *s++;
|
|
}
|
|
|
|
static inline void
|
|
mem_hash_mix_num(u64 *h, u64 val)
|
|
{
|
|
mem_hash_mix(h, &val, sizeof(val));
|
|
}
|
|
|
|
static inline uint
|
|
mem_hash_value(u64 *h)
|
|
{
|
|
return ((*h >> 32) ^ (*h & 0xffffffff));
|
|
}
|
|
|
|
static inline uint
|
|
mem_hash(const void *p, uint s)
|
|
{
|
|
static u64 h;
|
|
mem_hash_init(&h);
|
|
mem_hash_mix(&h, p, s);
|
|
return mem_hash_value(&h);
|
|
}
|
|
|
|
static inline uint
|
|
ptr_hash(void *ptr)
|
|
{
|
|
uintptr_t p = (uintptr_t) ptr;
|
|
return p ^ (p << 8) ^ (p >> 16);
|
|
}
|
|
|
|
#endif
|