diff options
Diffstat (limited to 'storage/innobase/include/lock0lock.h')
| -rw-r--r-- | storage/innobase/include/lock0lock.h | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/storage/innobase/include/lock0lock.h b/storage/innobase/include/lock0lock.h index b96f54e03a3..574c3dc1634 100644 --- a/storage/innobase/include/lock0lock.h +++ b/storage/innobase/include/lock0lock.h @@ -548,7 +548,7 @@ class lock_sys_t /** Hash table latch */ struct hash_latch -#if defined SRW_LOCK_DUMMY && !defined _WIN32 +#ifdef SUX_LOCK_GENERIC : private rw_lock { /** Wait for an exclusive lock */ @@ -577,15 +577,18 @@ class lock_sys_t { return memcmp(this, field_ref_zero, sizeof *this); } #endif }; - static_assert(sizeof(hash_latch) <= sizeof(void*), "compatibility"); public: struct hash_table { + /** Number of consecutive array[] elements occupied by a hash_latch */ + static constexpr size_t LATCH= sizeof(void*) >= sizeof(hash_latch) ? 1 : 2; + static_assert(sizeof(hash_latch) <= LATCH * sizeof(void*), "allocation"); + /** Number of array[] elements per hash_latch. - Must be one less than a power of 2. */ + Must be LATCH less than a power of 2. */ static constexpr size_t ELEMENTS_PER_LATCH= CPU_LEVEL1_DCACHE_LINESIZE / - sizeof(void*) - 1; + sizeof(void*) - LATCH; /** number of payload elements in array[]. Protected by lock_sys.latch. */ ulint n_cells; @@ -608,11 +611,13 @@ public: /** @return the index of an array element */ inline ulint calc_hash(ulint fold) const; /** @return raw array index converted to padded index */ - static ulint pad(ulint h) { return 1 + (h / ELEMENTS_PER_LATCH) + h; } + static ulint pad(ulint h) + { return LATCH + LATCH * (h / ELEMENTS_PER_LATCH) + h; } /** Get a latch. */ static hash_latch *latch(hash_cell_t *cell) { - void *l= ut_align_down(cell, (ELEMENTS_PER_LATCH + 1) * sizeof *cell); + void *l= ut_align_down(cell, sizeof *cell * + (ELEMENTS_PER_LATCH + LATCH)); return static_cast<hash_latch*>(l); } /** Get a hash table cell. */ @@ -646,7 +651,7 @@ private: /** Number of shared latches */ std::atomic<ulint> readers{0}; #endif -#if defined SRW_LOCK_DUMMY && !defined _WIN32 +#ifdef SUX_LOCK_GENERIC protected: /** mutex for hash_latch::wait() */ pthread_mutex_t hash_mutex; |