Adding upstream version 1:10.5.12.upstream/1%10.5.12upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 117 insertions, 0 deletions

diff --git a/sql/table_cache.h b/sql/table_cache.h
new file mode 100644
index 00000000..433df5e0
--- /dev/null
+++ b/sql/table_cache.h
@@ -0,0 +1,117 @@
+#ifndef TABLE_CACHE_H_INCLUDED
+#define TABLE_CACHE_H_INCLUDED
+/* Copyright (c) 2000, 2012, Oracle and/or its affiliates.
+   Copyright (c) 2010, 2011 Monty Program Ab
+   Copyright (C) 2013 Sergey Vojtovich and MariaDB Foundation
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
+
+
+struct Share_free_tables
+{
+  typedef I_P_List <TABLE, TABLE_share> List;
+  List list;
+  /** Avoid false sharing between instances */
+  char pad[CPU_LEVEL1_DCACHE_LINESIZE];
+};
+
+
+struct TDC_element
+{
+  uchar m_key[NAME_LEN + 1 + NAME_LEN + 1];
+  uint m_key_length;
+  bool flushed;
+  TABLE_SHARE *share;
+
+  /**
+    Protects ref_count, m_flush_tickets, all_tables, flushed, all_tables_refs.
+  */
+  mysql_mutex_t LOCK_table_share;
+  mysql_cond_t COND_release;
+  TDC_element *next, **prev;            /* Link to unused shares */
+  uint ref_count;                       /* How many TABLE objects uses this */
+  uint all_tables_refs;                 /* Number of refs to all_tables */
+  /**
+    List of tickets representing threads waiting for the share to be flushed.
+  */
+  Wait_for_flush_list m_flush_tickets;
+  /*
+    Doubly-linked (back-linked) lists of used and unused TABLE objects
+    for this share.
+  */
+  All_share_tables_list all_tables;
+  /** Avoid false sharing between TDC_element and free_tables */
+  char pad[CPU_LEVEL1_DCACHE_LINESIZE];
+  Share_free_tables free_tables[1];
+
+  inline void wait_for_refs(uint my_refs);
+  void flush(THD *thd, bool mark_flushed);
+  void flush_unused(bool mark_flushed);
+};
+
+
+extern ulong tdc_size;
+extern ulong tc_size;
+extern uint32 tc_instances;
+
+extern bool tdc_init(void);
+extern void tdc_start_shutdown(void);
+extern void tdc_deinit(void);
+extern ulong tdc_records(void);
+extern void tdc_purge(bool all);
+extern TDC_element *tdc_lock_share(THD *thd, const char *db,
+                                   const char *table_name);
+extern void tdc_unlock_share(TDC_element *element);
+int tdc_share_is_cached(THD *thd, const char *db, const char *table_name);
+extern TABLE_SHARE *tdc_acquire_share(THD *thd, TABLE_LIST *tl, uint flags,
+                                      TABLE **out_table= 0);
+extern void tdc_release_share(TABLE_SHARE *share);
+void tdc_remove_referenced_share(THD *thd, TABLE_SHARE *share);
+void tdc_remove_table(THD *thd, const char *db, const char *table_name);
+
+extern int tdc_wait_for_old_version(THD *thd, const char *db,
+                                    const char *table_name,
+                                    ulong wait_timeout, uint deadlock_weight);
+extern int tdc_iterate(THD *thd, my_hash_walk_action action, void *argument,
+                       bool no_dups= false);
+
+extern uint tc_records(void);
+int show_tc_active_instances(THD *thd, SHOW_VAR *var, char *buff,
+                             enum enum_var_type scope);
+extern void tc_purge();
+extern void tc_add_table(THD *thd, TABLE *table);
+extern void tc_release_table(TABLE *table);
+extern TABLE *tc_acquire_table(THD *thd, TDC_element *element);
+
+/**
+  Create a table cache key for non-temporary table.
+
+  @param key         Buffer for key (must be at least NAME_LEN*2+2 bytes).
+  @param db          Database name.
+  @param table_name  Table name.
+
+  @return Length of key.
+*/
+
+inline uint tdc_create_key(char *key, const char *db, const char *table_name)
+{
+  /*
+    In theory caller should ensure that both db and table_name are
+    not longer than NAME_LEN bytes. In practice we play safe to avoid
+    buffer overruns.
+  */
+  return (uint) (strmake(strmake(key, db, NAME_LEN) + 1, table_name,
+                         NAME_LEN) - key + 1);
+}
+#endif /* TABLE_CACHE_H_INCLUDED */