1 /* 2 * QEMU block throttling group infrastructure 3 * 4 * Copyright (C) Nodalink, EURL. 2014 5 * Copyright (C) Igalia, S.L. 2015 6 * 7 * Authors: 8 * Benoît Canet <benoit.canet@nodalink.com> 9 * Alberto Garcia <berto@igalia.com> 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License as 13 * published by the Free Software Foundation; either version 2 or 14 * (at your option) version 3 of the License. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, see <http://www.gnu.org/licenses/>. 23 */ 24 25 #ifndef THROTTLE_GROUPS_H 26 #define THROTTLE_GROUPS_H 27 28 #include "qemu/throttle.h" 29 #include "block/block_int.h" 30 31 /* The ThrottleGroupMember structure indicates membership in a ThrottleGroup 32 * and holds related data. 33 */ 34 35 typedef struct ThrottleGroupMember { 36 AioContext *aio_context; 37 /* throttled_reqs_lock protects the CoQueues for throttled requests. */ 38 CoMutex throttled_reqs_lock; 39 CoQueue throttled_reqs[2]; 40 41 /* Nonzero if the I/O limits are currently being ignored; generally 42 * it is zero. Accessed with atomic operations. 43 */ 44 unsigned int io_limits_disabled; 45 46 /* The following fields are protected by the ThrottleGroup lock. 47 * See the ThrottleGroup documentation for details. 48 * throttle_state tells us if I/O limits are configured. */ 49 ThrottleState *throttle_state; 50 ThrottleTimers throttle_timers; 51 unsigned pending_reqs[2]; 52 QLIST_ENTRY(ThrottleGroupMember) round_robin; 53 54 } ThrottleGroupMember; 55 56 #define TYPE_THROTTLE_GROUP "throttle-group" 57 #define THROTTLE_GROUP(obj) OBJECT_CHECK(ThrottleGroup, (obj), TYPE_THROTTLE_GROUP) 58 59 const char *throttle_group_get_name(ThrottleGroupMember *tgm); 60 61 ThrottleState *throttle_group_incref(const char *name); 62 void throttle_group_unref(ThrottleState *ts); 63 64 void throttle_group_config(ThrottleGroupMember *tgm, ThrottleConfig *cfg); 65 void throttle_group_get_config(ThrottleGroupMember *tgm, ThrottleConfig *cfg); 66 67 void throttle_group_register_tgm(ThrottleGroupMember *tgm, 68 const char *groupname, 69 AioContext *ctx); 70 void throttle_group_unregister_tgm(ThrottleGroupMember *tgm); 71 void throttle_group_restart_tgm(ThrottleGroupMember *tgm); 72 73 void coroutine_fn throttle_group_co_io_limits_intercept(ThrottleGroupMember *tgm, 74 unsigned int bytes, 75 bool is_write); 76 void throttle_group_attach_aio_context(ThrottleGroupMember *tgm, 77 AioContext *new_context); 78 void throttle_group_detach_aio_context(ThrottleGroupMember *tgm); 79 /* 80 * throttle_group_exists() must be called under the global 81 * mutex. 82 */ 83 bool throttle_group_exists(const char *name); 84 85 #endif 86