mirror of
https://git.proxmox.com/git/mirror_zfs.git
synced 2024-12-27 11:29:36 +03:00
186898bbb5
Problem Statement ================= ZFS Channel program scripts currently require a timeout, so that hung or long-running scripts return a timeout error instead of causing ZFS to get wedged. This limit can currently be set up to 100 million Lua instructions. Even with a limit in place, it would be desirable to have a sys admin (support engineer) be able to cancel a script that is taking a long time. Proposed Solution ================= Make it possible to abort a channel program by sending an interrupt signal.In the underlying txg_wait_sync function, switch the cv_wait to a cv_wait_sig to catch the signal. Once a signal is encountered, the dsl_sync_task function can install a Lua hook that will get called before the Lua interpreter executes a new line of code. The dsl_sync_task can resume with a standard txg_wait_sync call and wait for the txg to complete. Meanwhile, the hook will abort the script and indicate that the channel program was canceled. The kernel returns a EINTR to indicate that the channel program run was canceled. Porting notes: Added missing return value from cv_wait_sig() Authored by: Don Brady <don.brady@delphix.com> Reviewed by: Sebastien Roy <sebastien.roy@delphix.com> Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com> Reviewed by: Matt Ahrens <matt@delphix.com> Reviewed by: Sara Hartse <sara.hartse@delphix.com> Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov> Approved by: Robert Mustacchi <rm@joyent.com> Ported-by: Don Brady <don.brady@delphix.com> Signed-off-by: Don Brady <don.brady@delphix.com> OpenZFS-issue: https://www.illumos.org/issues/9425 OpenZFS-commit: https://github.com/illumos/illumos-gate/commit/d0cb1fb926 Closes #8904
128 lines
4.1 KiB
C
128 lines
4.1 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
|
|
* Copyright (c) 2012, 2017 by Delphix. All rights reserved.
|
|
*/
|
|
|
|
#ifndef _SYS_DSL_SYNCTASK_H
|
|
#define _SYS_DSL_SYNCTASK_H
|
|
|
|
#include <sys/txg.h>
|
|
#include <sys/zfs_context.h>
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
struct dsl_pool;
|
|
|
|
typedef int (dsl_checkfunc_t)(void *, dmu_tx_t *);
|
|
typedef void (dsl_syncfunc_t)(void *, dmu_tx_t *);
|
|
typedef void (dsl_sigfunc_t)(void *, dmu_tx_t *);
|
|
|
|
typedef enum zfs_space_check {
|
|
/*
|
|
* Normal space check: if there is less than 3.2% free space,
|
|
* the operation will fail. Operations which are logically
|
|
* creating things should use this (e.g. "zfs create", "zfs snapshot").
|
|
* User writes (via the ZPL / ZVOL) also fail at this point.
|
|
*/
|
|
ZFS_SPACE_CHECK_NORMAL,
|
|
|
|
/*
|
|
* Space check allows use of half the slop space. If there
|
|
* is less than 1.6% free space, the operation will fail. Most
|
|
* operations should use this (e.g. "zfs set", "zfs rename"),
|
|
* because we want them to succeed even after user writes are failing,
|
|
* so that they can be used as part of the space recovery process.
|
|
*/
|
|
ZFS_SPACE_CHECK_RESERVED,
|
|
|
|
/*
|
|
* Space check allows use of three quarters of the slop space.
|
|
* If there is less than 0.8% free space, the operation will
|
|
* fail.
|
|
*/
|
|
ZFS_SPACE_CHECK_EXTRA_RESERVED,
|
|
|
|
/*
|
|
* In all cases "zfs destroy" is expected to result in an net
|
|
* reduction of space, except one. When the pool has a
|
|
* checkpoint, space freed by "zfs destroy" will not actually
|
|
* free anything internally. Thus, it starts failing after
|
|
* three quarters of the slop space is exceeded.
|
|
*/
|
|
ZFS_SPACE_CHECK_DESTROY = ZFS_SPACE_CHECK_EXTRA_RESERVED,
|
|
|
|
/*
|
|
* A channel program can run a "zfs destroy" as part of its
|
|
* script and therefore has the same space_check policy when
|
|
* being evaluated.
|
|
*/
|
|
ZFS_SPACE_CHECK_ZCP_EVAL = ZFS_SPACE_CHECK_DESTROY,
|
|
|
|
/*
|
|
* No space check is performed. This level of space check should
|
|
* be used cautiously as operations that use it can even run when
|
|
* 0.8% capacity is left for use. In this scenario, if there is a
|
|
* checkpoint, async destroys are suspended and any kind of freeing
|
|
* can potentially add space instead of freeing it.
|
|
*
|
|
* See also the comments above spa_slop_shift.
|
|
*/
|
|
ZFS_SPACE_CHECK_NONE,
|
|
|
|
ZFS_SPACE_CHECK_DISCARD_CHECKPOINT = ZFS_SPACE_CHECK_NONE,
|
|
|
|
} zfs_space_check_t;
|
|
|
|
typedef struct dsl_sync_task {
|
|
txg_node_t dst_node;
|
|
struct dsl_pool *dst_pool;
|
|
uint64_t dst_txg;
|
|
int dst_space;
|
|
zfs_space_check_t dst_space_check;
|
|
dsl_checkfunc_t *dst_checkfunc;
|
|
dsl_syncfunc_t *dst_syncfunc;
|
|
void *dst_arg;
|
|
int dst_error;
|
|
boolean_t dst_nowaiter;
|
|
} dsl_sync_task_t;
|
|
|
|
void dsl_sync_task_sync(dsl_sync_task_t *, dmu_tx_t *);
|
|
int dsl_sync_task(const char *, dsl_checkfunc_t *,
|
|
dsl_syncfunc_t *, void *, int, zfs_space_check_t);
|
|
void dsl_sync_task_nowait(struct dsl_pool *, dsl_syncfunc_t *,
|
|
void *, int, zfs_space_check_t, dmu_tx_t *);
|
|
int dsl_early_sync_task(const char *, dsl_checkfunc_t *,
|
|
dsl_syncfunc_t *, void *, int, zfs_space_check_t);
|
|
void dsl_early_sync_task_nowait(struct dsl_pool *, dsl_syncfunc_t *,
|
|
void *, int, zfs_space_check_t, dmu_tx_t *);
|
|
int dsl_sync_task_sig(const char *, dsl_checkfunc_t *, dsl_syncfunc_t *,
|
|
dsl_sigfunc_t *, void *, int, zfs_space_check_t);
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* _SYS_DSL_SYNCTASK_H */
|