freebsd-dev/include/sys/txg.h
Ricardo M. Correia 54a179e7b8 Add API to wait for pending commit callbacks
This adds an API to wait for pending commit callbacks of already-synced
transactions to finish processing.  This is needed by the DMU-OSD in
Lustre during device finalization when some callbacks may still not be
called, this leads to non-zero reference count errors.  See lustre.org
bug 23931.
2011-02-16 11:20:06 -08:00

138 lines
4.2 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2010 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _SYS_TXG_H
#define _SYS_TXG_H
#include <sys/spa.h>
#include <sys/zfs_context.h>
#ifdef __cplusplus
extern "C" {
#endif
#define TXG_CONCURRENT_STATES 3 /* open, quiescing, syncing */
#define TXG_SIZE 4 /* next power of 2 */
#define TXG_MASK (TXG_SIZE - 1) /* mask for size */
#define TXG_INITIAL TXG_SIZE /* initial txg */
#define TXG_IDX (txg & TXG_MASK)
/* Number of txgs worth of frees we defer adding to in-core spacemaps */
#define TXG_DEFER_SIZE 2
#define TXG_WAIT 1ULL
#define TXG_NOWAIT 2ULL
typedef struct tx_cpu tx_cpu_t;
typedef struct txg_handle {
tx_cpu_t *th_cpu;
uint64_t th_txg;
} txg_handle_t;
typedef struct txg_node {
struct txg_node *tn_next[TXG_SIZE];
uint8_t tn_member[TXG_SIZE];
} txg_node_t;
typedef struct txg_list {
kmutex_t tl_lock;
size_t tl_offset;
txg_node_t *tl_head[TXG_SIZE];
} txg_list_t;
struct dsl_pool;
extern void txg_init(struct dsl_pool *dp, uint64_t txg);
extern void txg_fini(struct dsl_pool *dp);
extern void txg_sync_start(struct dsl_pool *dp);
extern void txg_sync_stop(struct dsl_pool *dp);
extern uint64_t txg_hold_open(struct dsl_pool *dp, txg_handle_t *txghp);
extern void txg_rele_to_quiesce(txg_handle_t *txghp);
extern void txg_rele_to_sync(txg_handle_t *txghp);
extern void txg_register_callbacks(txg_handle_t *txghp, list_t *tx_callbacks);
/*
* Delay the caller by the specified number of ticks or until
* the txg closes (whichever comes first). This is intended
* to be used to throttle writers when the system nears its
* capacity.
*/
extern void txg_delay(struct dsl_pool *dp, uint64_t txg, int ticks);
/*
* Wait until the given transaction group has finished syncing.
* Try to make this happen as soon as possible (eg. kick off any
* necessary syncs immediately). If txg==0, wait for the currently open
* txg to finish syncing.
*/
extern void txg_wait_synced(struct dsl_pool *dp, uint64_t txg);
/*
* Wait until the given transaction group, or one after it, is
* the open transaction group. Try to make this happen as soon
* as possible (eg. kick off any necessary syncs immediately).
* If txg == 0, wait for the next open txg.
*/
extern void txg_wait_open(struct dsl_pool *dp, uint64_t txg);
/*
* Returns TRUE if we are "backed up" waiting for the syncing
* transaction to complete; otherwise returns FALSE.
*/
extern boolean_t txg_stalled(struct dsl_pool *dp);
/* returns TRUE if someone is waiting for the next txg to sync */
extern boolean_t txg_sync_waiting(struct dsl_pool *dp);
/*
* Wait for pending commit callbacks of already-synced transactions to finish
* processing.
*/
extern void txg_wait_callbacks(struct dsl_pool *dp);
/*
* Per-txg object lists.
*/
#define TXG_CLEAN(txg) ((txg) - 1)
extern void txg_list_create(txg_list_t *tl, size_t offset);
extern void txg_list_destroy(txg_list_t *tl);
extern int txg_list_empty(txg_list_t *tl, uint64_t txg);
extern int txg_list_add(txg_list_t *tl, void *p, uint64_t txg);
extern int txg_list_add_tail(txg_list_t *tl, void *p, uint64_t txg);
extern void *txg_list_remove(txg_list_t *tl, uint64_t txg);
extern void *txg_list_remove_this(txg_list_t *tl, void *p, uint64_t txg);
extern int txg_list_member(txg_list_t *tl, void *p, uint64_t txg);
extern void *txg_list_head(txg_list_t *tl, uint64_t txg);
extern void *txg_list_next(txg_list_t *tl, void *p, uint64_t txg);
#ifdef __cplusplus
}
#endif
#endif /* _SYS_TXG_H */