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+/* Copyright (C) 2012, 2020, MariaDB
+
+ 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 Street, Fifth Floor, Boston, MA 02110-1335 USA */
+
+#pragma once
+#ifdef HAVE_POOL_OF_THREADS
+#define MAX_THREAD_GROUPS 100000
+
+/* Threadpool parameters */
+extern uint threadpool_min_threads; /* Minimum threads in pool */
+extern uint threadpool_idle_timeout; /* Shutdown idle worker threads after this timeout */
+extern uint threadpool_size; /* Number of parallel executing threads */
+extern uint threadpool_max_size;
+extern uint threadpool_stall_limit; /* time interval in milliseconds for stall checks*/
+extern uint threadpool_max_threads; /* Maximum threads in pool */
+extern uint threadpool_oversubscribe; /* Maximum active threads in group */
+extern uint threadpool_prio_kickup_timer; /* Time before low prio item gets prio boost */
+extern my_bool threadpool_exact_stats; /* Better queueing time stats for information_schema, at small performance cost */
+extern my_bool threadpool_dedicated_listener; /* Listener thread does not pick up work items. */
+#ifdef _WIN32
+extern uint threadpool_mode; /* Thread pool implementation , windows or generic */
+#define TP_MODE_WINDOWS 0
+#define TP_MODE_GENERIC 1
+#endif
+
+#define DEFAULT_THREADPOOL_STALL_LIMIT 500U
+
+struct TP_connection;
+extern void tp_callback(TP_connection *c);
+extern void tp_timeout_handler(TP_connection *c);
+
+
+
+/*
+ Threadpool statistics
+*/
+struct TP_STATISTICS
+{
+ /* Current number of worker thread. */
+ Atomic_counter<uint32_t> num_worker_threads;
+};
+
+extern TP_STATISTICS tp_stats;
+
+
+/* Functions to set threadpool parameters */
+extern void tp_set_min_threads(uint val);
+extern void tp_set_max_threads(uint val);
+extern void tp_set_threadpool_size(uint val);
+extern void tp_set_threadpool_stall_limit(uint val);
+extern int tp_get_idle_thread_count();
+extern int tp_get_thread_count();
+
+
+enum TP_PRIORITY {
+ TP_PRIORITY_HIGH,
+ TP_PRIORITY_LOW,
+ TP_PRIORITY_AUTO
+};
+
+
+enum TP_STATE
+{
+ TP_STATE_IDLE,
+ TP_STATE_RUNNING,
+ TP_STATE_PENDING
+};
+
+/*
+ Connection structure, encapsulates THD + structures for asynchronous
+ IO and pool.
+
+ Platform specific parts are specified in subclasses called connection_t,
+ inside threadpool_win.cc and threadpool_unix.cc
+*/
+
+class CONNECT;
+
+struct TP_connection
+{
+ THD* thd;
+ CONNECT* connect;
+ TP_STATE state;
+ TP_PRIORITY priority;
+ TP_connection(CONNECT *c) :
+ thd(0),
+ connect(c),
+ state(TP_STATE_IDLE),
+ priority(TP_PRIORITY_HIGH)
+ {}
+
+ virtual ~TP_connection()
+ {};
+
+ /* Initialize io structures windows threadpool, epoll etc */
+ virtual int init() = 0;
+
+ virtual void set_io_timeout(int sec) = 0;
+
+ /* Read for the next client command (async) with specified timeout */
+ virtual int start_io() = 0;
+
+ virtual void wait_begin(int type)= 0;
+ virtual void wait_end() = 0;
+
+};
+
+
+struct TP_pool
+{
+ virtual ~TP_pool(){};
+ virtual int init()= 0;
+ virtual TP_connection *new_connection(CONNECT *)= 0;
+ virtual void add(TP_connection *c)= 0;
+ virtual int set_max_threads(uint){ return 0; }
+ virtual int set_min_threads(uint){ return 0; }
+ virtual int set_pool_size(uint){ return 0; }
+ virtual int set_idle_timeout(uint){ return 0; }
+ virtual int set_oversubscribe(uint){ return 0; }
+ virtual int set_stall_limit(uint){ return 0; }
+ virtual int get_thread_count() { return tp_stats.num_worker_threads; }
+ virtual int get_idle_thread_count(){ return 0; }
+};
+
+#ifdef _WIN32
+struct TP_pool_win:TP_pool
+{
+ TP_pool_win();
+ virtual int init();
+ virtual ~TP_pool_win();
+ virtual TP_connection *new_connection(CONNECT *c);
+ virtual void add(TP_connection *);
+ virtual int set_max_threads(uint);
+ virtual int set_min_threads(uint);
+};
+#endif
+
+struct TP_pool_generic :TP_pool
+{
+ TP_pool_generic();
+ ~TP_pool_generic();
+ virtual int init();
+ virtual TP_connection *new_connection(CONNECT *c);
+ virtual void add(TP_connection *);
+ virtual int set_pool_size(uint);
+ virtual int set_stall_limit(uint);
+ virtual int get_idle_thread_count();
+};
+
+#endif /* HAVE_POOL_OF_THREADS */