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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 193 Based on 1 normalized pattern(s): this copyrighted material is made available to anyone wishing to use modify copy or redistribute it subject to the terms and conditions of the gnu general public license v 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 45 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528170027.342746075@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-28 09:57:20 -07:00
// SPDX-License-Identifier: GPL-2.0-only
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
/******************************************************************************
*******************************************************************************
**
** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
dlm: fix ordering of bast and cast When both blocking and completion callbacks are queued for lock, the dlm would always deliver the completion callback (cast) first. In some cases the blocking callback (bast) is queued before the cast, though, and should be delivered first. This patch keeps track of the order in which they were queued and delivers them in that order. This patch also keeps track of the granted mode in the last cast and eliminates the following bast if the bast mode is compatible with the preceding cast mode. This happens when a remotely mastered lock is demoted, e.g. EX->NL, in which case the local node queues a cast immediately after sending the demote message. In this way a cast can be queued for a mode, e.g. NL, that makes an in-transit bast extraneous. Signed-off-by: David Teigland <teigland@redhat.com>
2010-02-24 11:08:18 -06:00
** Copyright (C) 2004-2010 Red Hat, Inc. All rights reserved.
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
**
**
*******************************************************************************
******************************************************************************/
fs: dlm: initial support for tracepoints This patch adds initial support for dlm tracepoints. It will introduce tracepoints to dlm main functionality dlm_lock()/dlm_unlock() and their complete ast() callback or blocking bast() callback. The lock/unlock functionality has a start and end tracepoint, this is because there exists a race in case if would have a tracepoint at the end position only the complete/blocking callbacks could occur before. To work with eBPF tracing and using their lookup hash functionality there could be problems that an entry was not inserted yet. However use the start functionality for hash insert and check again in end functionality if there was an dlm internal error so there is no ast callback. In further it might also that locks with local masters will occur those callbacks immediately so we must have such functionality. I did not make everything accessible yet, although it seems eBPF can be used to access a lot of internal datastructures if it's aware of the struct definitions of the running kernel instance. We still can change it, if you do eBPF experiments e.g. time measurements between lock and callback functionality you can simple use the local lkb_id field as hash value in combination with the lockspace id if you have multiple lockspaces. Otherwise you can simple use trace-cmd for some functionality, e.g. `trace-cmd record -e dlm` and `trace-cmd report` afterwards. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2021-11-02 15:17:15 -04:00
#include <trace/events/dlm.h>
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
#include "dlm_internal.h"
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
#include "memory.h"
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
#include "lock.h"
[DLM] dlm: user locks This changes the way the dlm handles user locks. The core dlm is now aware of user locks so they can be dealt with more efficiently. There is no more dlm_device module which previously managed its own duplicate copy of every user lock. Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-07-12 16:44:04 -05:00
#include "user.h"
fs: Include appropriate header file in dlm/ast.c Include appropriate header file fs/dlm/ast.h in fs/dlm/ast.c because it contains function prototypes of some functions defined in fs/dlm/ast.c. This also eliminates the following warning in fs/dlm/ast: fs/dlm/ast.c:52:5: warning: no previous prototype for ‘dlm_add_lkb_callback’ [-Wmissing-prototypes] fs/dlm/ast.c:113:5: warning: no previous prototype for ‘dlm_rem_lkb_callback’ [-Wmissing-prototypes] fs/dlm/ast.c:174:6: warning: no previous prototype for ‘dlm_add_cb’ [-Wmissing-prototypes] fs/dlm/ast.c:212:6: warning: no previous prototype for ‘dlm_callback_work’ [-Wmissing-prototypes] fs/dlm/ast.c:267:5: warning: no previous prototype for ‘dlm_callback_start’ [-Wmissing-prototypes] fs/dlm/ast.c:278:6: warning: no previous prototype for ‘dlm_callback_stop’ [-Wmissing-prototypes] fs/dlm/ast.c:284:6: warning: no previous prototype for ‘dlm_callback_suspend’ [-Wmissing-prototypes] fs/dlm/ast.c:292:6: warning: no previous prototype for ‘dlm_callback_resume’ [-Wmissing-prototypes] Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: David Teigland <teigland@redhat.com>
2014-02-09 18:19:17 +05:30
#include "ast.h"
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
void dlm_release_callback(struct kref *ref)
{
struct dlm_callback *cb = container_of(ref, struct dlm_callback, ref);
dlm_free_cb(cb);
}
void dlm_callback_set_last_ptr(struct dlm_callback **from,
struct dlm_callback *to)
{
if (*from)
kref_put(&(*from)->ref, dlm_release_callback);
if (to)
kref_get(&to->ref);
*from = to;
}
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
int dlm_enqueue_lkb_callback(struct dlm_lkb *lkb, uint32_t flags, int mode,
int status, uint32_t sbflags)
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
{
struct dlm_ls *ls = lkb->lkb_resource->res_ls;
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
int rv = DLM_ENQUEUE_CALLBACK_SUCCESS;
struct dlm_callback *cb;
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
int prev_mode;
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
if (flags & DLM_CB_BAST) {
/* if cb is a bast, it should be skipped if the blocking mode is
* compatible with the last granted mode
*/
if (lkb->lkb_last_cast) {
if (dlm_modes_compat(mode, lkb->lkb_last_cast->mode)) {
log_debug(ls, "skip %x bast mode %d for cast mode %d",
lkb->lkb_id, mode,
lkb->lkb_last_cast->mode);
goto out;
}
}
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
/*
* Suppress some redundant basts here, do more on removal.
* Don't even add a bast if the callback just before it
* is a bast for the same mode or a more restrictive mode.
* (the addional > PR check is needed for PR/CW inversion)
*/
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
if (lkb->lkb_last_cb && lkb->lkb_last_cb->flags & DLM_CB_BAST) {
prev_mode = lkb->lkb_last_cb->mode;
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
if ((prev_mode == mode) ||
(prev_mode > mode && prev_mode > DLM_LOCK_PR)) {
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
log_debug(ls, "skip %x add bast mode %d for bast mode %d",
lkb->lkb_id, mode, prev_mode);
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
goto out;
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
}
}
}
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
cb = dlm_allocate_cb();
if (!cb) {
rv = DLM_ENQUEUE_CALLBACK_FAILURE;
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
goto out;
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
}
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
cb->flags = flags;
cb->mode = mode;
cb->sb_status = status;
cb->sb_flags = (sbflags & 0x000000FF);
kref_init(&cb->ref);
fs: dlm: fix DLM_IFL_CB_PENDING gets overwritten This patch introduce a new internal flag per lkb value to handle internal flags which are handled not on wire. The current lkb internal flags stored as lkb->lkb_flags are split in upper and lower bits, the lower bits are used to share internal flags over wire for other cluster wide lkb copies on other nodes. In commit 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks") we introduced a new internal flag for pending callbacks for the dlm callback queue. This flag is protected by the lkb->lkb_cb_lock lock. This patch overlooked that on dlm receive path and the mentioned upper and lower bits, that dlm will read the flags, mask it and write it back. As example receive_flags() in fs/dlm/lock.c. This flag manipulation is not done atomically and is not protected by lkb->lkb_cb_lock. This has unknown side effects of the current callback handling. In future we should move to set/clear/test bit functionality and avoid read, mask and writing back flag values. In later patches we will move the upper parts to the new introduced internal lkb flags which are not shared between other cluster nodes to the new non shared internal flag field to avoid similar issues. Cc: stable@vger.kernel.org Fixes: 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks") Reported-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2023-03-06 15:48:08 -05:00
if (!test_and_set_bit(DLM_IFL_CB_PENDING_BIT, &lkb->lkb_iflags))
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
rv = DLM_ENQUEUE_CALLBACK_NEED_SCHED;
fs: dlm: fix DLM_IFL_CB_PENDING gets overwritten This patch introduce a new internal flag per lkb value to handle internal flags which are handled not on wire. The current lkb internal flags stored as lkb->lkb_flags are split in upper and lower bits, the lower bits are used to share internal flags over wire for other cluster wide lkb copies on other nodes. In commit 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks") we introduced a new internal flag for pending callbacks for the dlm callback queue. This flag is protected by the lkb->lkb_cb_lock lock. This patch overlooked that on dlm receive path and the mentioned upper and lower bits, that dlm will read the flags, mask it and write it back. As example receive_flags() in fs/dlm/lock.c. This flag manipulation is not done atomically and is not protected by lkb->lkb_cb_lock. This has unknown side effects of the current callback handling. In future we should move to set/clear/test bit functionality and avoid read, mask and writing back flag values. In later patches we will move the upper parts to the new introduced internal lkb flags which are not shared between other cluster nodes to the new non shared internal flag field to avoid similar issues. Cc: stable@vger.kernel.org Fixes: 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks") Reported-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2023-03-06 15:48:08 -05:00
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
list_add_tail(&cb->list, &lkb->lkb_callbacks);
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
if (flags & DLM_CB_CAST)
dlm_callback_set_last_ptr(&lkb->lkb_last_cast, cb);
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
dlm_callback_set_last_ptr(&lkb->lkb_last_cb, cb);
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
out:
return rv;
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
}
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
int dlm_dequeue_lkb_callback(struct dlm_lkb *lkb, struct dlm_callback **cb)
{
/* oldest undelivered cb is callbacks first entry */
*cb = list_first_entry_or_null(&lkb->lkb_callbacks,
struct dlm_callback, list);
if (!*cb)
return DLM_DEQUEUE_CALLBACK_EMPTY;
/* remove it from callbacks so shift others down */
list_del(&(*cb)->list);
if (list_empty(&lkb->lkb_callbacks))
return DLM_DEQUEUE_CALLBACK_LAST;
return DLM_DEQUEUE_CALLBACK_SUCCESS;
}
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
void dlm_add_cb(struct dlm_lkb *lkb, uint32_t flags, int mode, int status,
uint32_t sbflags)
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
{
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
struct dlm_ls *ls = lkb->lkb_resource->res_ls;
dlm: record full callback state Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
2011-02-21 14:58:21 -06:00
int rv;
fs: dlm: change dflags to use atomic bits Currently manipulating lkb_dflags assumes to held the rsb lock assigned to the lkb. This is held by dlm message processing after certain time to lookup the right rsb from the received lkb message id. For user space locks flags, which is currently the only use case for lkb_dflags, flags are also being set during dlm character device handling without holding the rsb lock. To minimize the risk that bit operations are getting corrupted we switch to atomic bit operations. This patch will also introduce helpers to snapshot atomic bit values in an non atomic way. There might be still issues with the flag handling e.g. running in case of manipulating bit ops and snapshot them at the same time, but this patch minimize them and will start to use atomic bit operations. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2023-03-06 15:48:15 -05:00
if (test_bit(DLM_DFL_USER_BIT, &lkb->lkb_dflags)) {
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
dlm_user_add_ast(lkb, flags, mode, status, sbflags);
[DLM] dlm: user locks This changes the way the dlm handles user locks. The core dlm is now aware of user locks so they can be dealt with more efficiently. There is no more dlm_device module which previously managed its own duplicate copy of every user lock. Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-07-12 16:44:04 -05:00
return;
}
fs: dlm: use spin lock instead of mutex There is no need to use a mutex in those hot path sections. We change it to spin lock to serve callbacks more faster by not allowing schedule. The locked sections will not be locked for a long time. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:19 -04:00
spin_lock(&lkb->lkb_cb_lock);
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
rv = dlm_enqueue_lkb_callback(lkb, flags, mode, status, sbflags);
switch (rv) {
case DLM_ENQUEUE_CALLBACK_NEED_SCHED:
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
kref_get(&lkb->lkb_ref);
fs: dlm: convert ls_cb_mutex mutex to spinlock This patch converts the ls_cb_mutex mutex to a spinlock, there is no sleepable context when this lock is held. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:18 -04:00
spin_lock(&ls->ls_cb_lock);
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
if (test_bit(LSFL_CB_DELAY, &ls->ls_flags)) {
list_add(&lkb->lkb_cb_list, &ls->ls_cb_delay);
} else {
queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
}
fs: dlm: convert ls_cb_mutex mutex to spinlock This patch converts the ls_cb_mutex mutex to a spinlock, there is no sleepable context when this lock is held. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:18 -04:00
spin_unlock(&ls->ls_cb_lock);
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
break;
case DLM_ENQUEUE_CALLBACK_FAILURE:
fs: dlm: ast do WARN_ON_ONCE() on hotpath This patch changes the ast hotpath functionality in very unlikely cases that we do WARN_ON_ONCE() instead of WARN_ON() to not spamming the console output if we run into states that it would occur over and over again. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-11-17 17:11:42 -05:00
WARN_ON_ONCE(1);
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
break;
case DLM_ENQUEUE_CALLBACK_SUCCESS:
break;
default:
fs: dlm: ast do WARN_ON_ONCE() on hotpath This patch changes the ast hotpath functionality in very unlikely cases that we do WARN_ON_ONCE() instead of WARN_ON() to not spamming the console output if we run into states that it would occur over and over again. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-11-17 17:11:42 -05:00
WARN_ON_ONCE(1);
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
break;
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
}
fs: dlm: use spin lock instead of mutex There is no need to use a mutex in those hot path sections. We change it to spin lock to serve callbacks more faster by not allowing schedule. The locked sections will not be locked for a long time. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:19 -04:00
spin_unlock(&lkb->lkb_cb_lock);
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
}
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
void dlm_callback_work(struct work_struct *work)
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
{
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
struct dlm_lkb *lkb = container_of(work, struct dlm_lkb, lkb_cb_work);
struct dlm_ls *ls = lkb->lkb_resource->res_ls;
dlm: fix ordering of bast and cast When both blocking and completion callbacks are queued for lock, the dlm would always deliver the completion callback (cast) first. In some cases the blocking callback (bast) is queued before the cast, though, and should be delivered first. This patch keeps track of the order in which they were queued and delivers them in that order. This patch also keeps track of the granted mode in the last cast and eliminates the following bast if the bast mode is compatible with the preceding cast mode. This happens when a remotely mastered lock is demoted, e.g. EX->NL, in which case the local node queues a cast immediately after sending the demote message. In this way a cast can be queued for a mode, e.g. NL, that makes an in-transit bast extraneous. Signed-off-by: David Teigland <teigland@redhat.com>
2010-02-24 11:08:18 -06:00
void (*castfn) (void *astparam);
void (*bastfn) (void *astparam, int mode);
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
struct dlm_callback *cb;
int rv;
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
fs: dlm: use spin lock instead of mutex There is no need to use a mutex in those hot path sections. We change it to spin lock to serve callbacks more faster by not allowing schedule. The locked sections will not be locked for a long time. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:19 -04:00
spin_lock(&lkb->lkb_cb_lock);
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
rv = dlm_dequeue_lkb_callback(lkb, &cb);
fs: dlm: clear pending bit when queue was empty This patch clears the DLM_IFL_CB_PENDING_BIT flag which will be set when there is callback work queued when there was no callback to dequeue. It is a buggy case and should never happen, that's why there is a WARN_ON(). However if the case happens we are prepared to somehow recover from it. Cc: stable@vger.kernel.org Fixes: 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks") Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2023-05-29 17:44:30 -04:00
if (WARN_ON_ONCE(rv == DLM_DEQUEUE_CALLBACK_EMPTY)) {
clear_bit(DLM_IFL_CB_PENDING_BIT, &lkb->lkb_iflags);
spin_unlock(&lkb->lkb_cb_lock);
fs: dlm: drop lkb ref in bug case This patch will drop the lkb reference in an very unlikely case which should in practice not happened. However if it happens we cleanup the reference just in case. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-11-17 17:11:41 -05:00
goto out;
fs: dlm: clear pending bit when queue was empty This patch clears the DLM_IFL_CB_PENDING_BIT flag which will be set when there is callback work queued when there was no callback to dequeue. It is a buggy case and should never happen, that's why there is a WARN_ON(). However if the case happens we are prepared to somehow recover from it. Cc: stable@vger.kernel.org Fixes: 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks") Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2023-05-29 17:44:30 -04:00
}
spin_unlock(&lkb->lkb_cb_lock);
dlm: fix ordering of bast and cast When both blocking and completion callbacks are queued for lock, the dlm would always deliver the completion callback (cast) first. In some cases the blocking callback (bast) is queued before the cast, though, and should be delivered first. This patch keeps track of the order in which they were queued and delivers them in that order. This patch also keeps track of the granted mode in the last cast and eliminates the following bast if the bast mode is compatible with the preceding cast mode. This happens when a remotely mastered lock is demoted, e.g. EX->NL, in which case the local node queues a cast immediately after sending the demote message. In this way a cast can be queued for a mode, e.g. NL, that makes an in-transit bast extraneous. Signed-off-by: David Teigland <teigland@redhat.com>
2010-02-24 11:08:18 -06:00
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
for (;;) {
castfn = lkb->lkb_astfn;
bastfn = lkb->lkb_bastfn;
if (cb->flags & DLM_CB_BAST) {
trace_dlm_bast(ls, lkb, cb->mode);
fs: dlm: move last cast bast time to function call This patch moves the debugging information of the last cast and bast time when calling the last and bast function call. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:20 -04:00
lkb->lkb_last_bast_time = ktime_get();
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
lkb->lkb_last_bast_mode = cb->mode;
bastfn(lkb->lkb_astparam, cb->mode);
} else if (cb->flags & DLM_CB_CAST) {
lkb->lkb_lksb->sb_status = cb->sb_status;
lkb->lkb_lksb->sb_flags = cb->sb_flags;
fs: dlm: remove additional dereference of lksb This patch removes a dereference of lksb of lkb when calling ast tracepoint. First it reduces additional overhead, even if traces are not active. Second we can deference it in TP_fast_assign from the existing lkb parameter. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-06-22 14:45:11 -04:00
trace_dlm_ast(ls, lkb);
fs: dlm: move last cast bast time to function call This patch moves the debugging information of the last cast and bast time when calling the last and bast function call. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:20 -04:00
lkb->lkb_last_cast_time = ktime_get();
fs: dlm: change ast and bast trace order This patch moves the trace calls for ast and bast to before the ast and bast callback functions are called rather than after. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-06-22 14:45:10 -04:00
castfn(lkb->lkb_astparam);
dlm: fix ordering of bast and cast When both blocking and completion callbacks are queued for lock, the dlm would always deliver the completion callback (cast) first. In some cases the blocking callback (bast) is queued before the cast, though, and should be delivered first. This patch keeps track of the order in which they were queued and delivers them in that order. This patch also keeps track of the granted mode in the last cast and eliminates the following bast if the bast mode is compatible with the preceding cast mode. This happens when a remotely mastered lock is demoted, e.g. EX->NL, in which case the local node queues a cast immediately after sending the demote message. In this way a cast can be queued for a mode, e.g. NL, that makes an in-transit bast extraneous. Signed-off-by: David Teigland <teigland@redhat.com>
2010-02-24 11:08:18 -06:00
}
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
kref_put(&cb->ref, dlm_release_callback);
spin_lock(&lkb->lkb_cb_lock);
rv = dlm_dequeue_lkb_callback(lkb, &cb);
if (rv == DLM_DEQUEUE_CALLBACK_EMPTY) {
fs: dlm: fix DLM_IFL_CB_PENDING gets overwritten This patch introduce a new internal flag per lkb value to handle internal flags which are handled not on wire. The current lkb internal flags stored as lkb->lkb_flags are split in upper and lower bits, the lower bits are used to share internal flags over wire for other cluster wide lkb copies on other nodes. In commit 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks") we introduced a new internal flag for pending callbacks for the dlm callback queue. This flag is protected by the lkb->lkb_cb_lock lock. This patch overlooked that on dlm receive path and the mentioned upper and lower bits, that dlm will read the flags, mask it and write it back. As example receive_flags() in fs/dlm/lock.c. This flag manipulation is not done atomically and is not protected by lkb->lkb_cb_lock. This has unknown side effects of the current callback handling. In future we should move to set/clear/test bit functionality and avoid read, mask and writing back flag values. In later patches we will move the upper parts to the new introduced internal lkb flags which are not shared between other cluster nodes to the new non shared internal flag field to avoid similar issues. Cc: stable@vger.kernel.org Fixes: 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks") Reported-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2023-03-06 15:48:08 -05:00
clear_bit(DLM_IFL_CB_PENDING_BIT, &lkb->lkb_iflags);
fs: dlm: use a non-static queue for callbacks This patch will introducde a queue implementation for callbacks by using the Linux lists. The current callback queue handling is implemented by a static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number inside the callback structure was used to see if the entries inside the static entry is valid or not. We don't need any sequence numbers anymore with a dynamic datastructure with grows and shrinks during runtime to offer such functionality. We assume that every callback will be delivered to the DLM user if once queued. Therefore the callback flag DLM_CB_SKIP was dropped and the check for skipping bast was moved before worker handling and not skip while the callback worker executes. This will reduce unnecessary queues of the callback worker. All last callback saves are pointers now and don't need to copied over. There is a reference counter for callback structures which will care about to free the callback structures at the right time if they are not referenced anymore. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:21 -04:00
spin_unlock(&lkb->lkb_cb_lock);
break;
}
spin_unlock(&lkb->lkb_cb_lock);
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
}
fs: dlm: drop lkb ref in bug case This patch will drop the lkb reference in an very unlikely case which should in practice not happened. However if it happens we cleanup the reference just in case. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-11-17 17:11:41 -05:00
out:
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
/* undo kref_get from dlm_add_callback, may cause lkb to be freed */
dlm_put_lkb(lkb);
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
}
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
int dlm_callback_start(struct dlm_ls *ls)
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
{
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
ls->ls_callback_wq = alloc_workqueue("dlm_callback",
dlm: don't specify WQ_UNBOUND for the ast callback workqueue This patch removes the WQ_UNBOUND flag (which implies WQ_HIGHPRI) from the DLM's ast work queue, in favor of just WQ_HIGHPRI. This has been shown to cause a 19 percent performance increase for simultaneous inode creates on GFS2 with fs_mark. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2016-10-19 11:34:54 -04:00
WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
if (!ls->ls_callback_wq) {
log_print("can't start dlm_callback workqueue");
return -ENOMEM;
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
}
return 0;
}
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
void dlm_callback_stop(struct dlm_ls *ls)
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
{
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
if (ls->ls_callback_wq)
destroy_workqueue(ls->ls_callback_wq);
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
}
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
void dlm_callback_suspend(struct dlm_ls *ls)
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
{
fs: dlm: LSFL_CB_DELAY only for kernel lockspaces This patch only set/clear the LSFL_CB_DELAY bit when it's actually a kernel lockspace signaled by if ls->ls_callback_wq is set or not set in this case. User lockspaces will never evaluate this flag. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-08-15 15:43:26 -04:00
if (ls->ls_callback_wq) {
fs: dlm: convert ls_cb_mutex mutex to spinlock This patch converts the ls_cb_mutex mutex to a spinlock, there is no sleepable context when this lock is held. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:18 -04:00
spin_lock(&ls->ls_cb_lock);
fs: dlm: LSFL_CB_DELAY only for kernel lockspaces This patch only set/clear the LSFL_CB_DELAY bit when it's actually a kernel lockspace signaled by if ls->ls_callback_wq is set or not set in this case. User lockspaces will never evaluate this flag. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-08-15 15:43:26 -04:00
set_bit(LSFL_CB_DELAY, &ls->ls_flags);
fs: dlm: convert ls_cb_mutex mutex to spinlock This patch converts the ls_cb_mutex mutex to a spinlock, there is no sleepable context when this lock is held. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:18 -04:00
spin_unlock(&ls->ls_cb_lock);
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
flush_workqueue(ls->ls_callback_wq);
fs: dlm: LSFL_CB_DELAY only for kernel lockspaces This patch only set/clear the LSFL_CB_DELAY bit when it's actually a kernel lockspace signaled by if ls->ls_callback_wq is set or not set in this case. User lockspaces will never evaluate this flag. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-08-15 15:43:26 -04:00
}
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
}
dlm: Don't swamp the CPU with callbacks queued during recovery Before this patch, recovery would cause all callbacks to be delayed, put on a queue, and afterward they were all queued to the callback work queue. This patch does the same thing, but occasionally takes a break after 25 of them so it won't swamp the CPU at the expense of other RT processes like corosync. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2018-11-08 14:04:50 -05:00
#define MAX_CB_QUEUE 25
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
void dlm_callback_resume(struct dlm_ls *ls)
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
{
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
struct dlm_lkb *lkb, *safe;
fs: dlm: make dlm_callback_resume quite This patch makes dlm_callback_resume info printout less noisy by accumulate all callback queues into one printout not in 25 times steps. It seems this printout became lately quite noisy in relationship with gfs2. Before: [241767.849302] dlm: bin: dlm_callback_resume 25 [241767.854846] dlm: bin: dlm_callback_resume 25 [241767.860373] dlm: bin: dlm_callback_resume 25 ... [241767.865920] dlm: bin: dlm_callback_resume 25 [241767.871352] dlm: bin: dlm_callback_resume 25 [241767.876733] dlm: bin: dlm_callback_resume 25 After the patch: [ 385.485728] dlm: gfs2: dlm_callback_resume 175 if zero it will not be printed out. Reported-by: Barry Marson <bmarson@redhat.com> Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2021-11-02 15:17:14 -04:00
int count = 0, sum = 0;
fs: dlm: use list_empty() to check last iteration This patch will use list_empty(&ls->ls_cb_delay) to check for last list iteration. In case of a multiply count of MAX_CB_QUEUE and the list is empty we do a extra goto more which we can avoid by checking on list_empty(). Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2021-11-30 14:47:14 -05:00
bool empty;
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
if (!ls->ls_callback_wq)
return;
dlm: Don't swamp the CPU with callbacks queued during recovery Before this patch, recovery would cause all callbacks to be delayed, put on a queue, and afterward they were all queued to the callback work queue. This patch does the same thing, but occasionally takes a break after 25 of them so it won't swamp the CPU at the expense of other RT processes like corosync. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2018-11-08 14:04:50 -05:00
more:
fs: dlm: convert ls_cb_mutex mutex to spinlock This patch converts the ls_cb_mutex mutex to a spinlock, there is no sleepable context when this lock is held. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:18 -04:00
spin_lock(&ls->ls_cb_lock);
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
list_for_each_entry_safe(lkb, safe, &ls->ls_cb_delay, lkb_cb_list) {
list_del_init(&lkb->lkb_cb_list);
queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
count++;
dlm: Don't swamp the CPU with callbacks queued during recovery Before this patch, recovery would cause all callbacks to be delayed, put on a queue, and afterward they were all queued to the callback work queue. This patch does the same thing, but occasionally takes a break after 25 of them so it won't swamp the CPU at the expense of other RT processes like corosync. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2018-11-08 14:04:50 -05:00
if (count == MAX_CB_QUEUE)
break;
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
}
fs: dlm: use list_empty() to check last iteration This patch will use list_empty(&ls->ls_cb_delay) to check for last list iteration. In case of a multiply count of MAX_CB_QUEUE and the list is empty we do a extra goto more which we can avoid by checking on list_empty(). Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2021-11-30 14:47:14 -05:00
empty = list_empty(&ls->ls_cb_delay);
fs: dlm: let dlm_add_cb queue work after resume only We should allow dlm_add_cb() to call queue_work() only after the recovery queued pending for delayed lkbs. This patch will move the switch LSFL_CB_DELAY after the delayed lkb work was processed. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:16 -04:00
if (empty)
clear_bit(LSFL_CB_DELAY, &ls->ls_flags);
fs: dlm: convert ls_cb_mutex mutex to spinlock This patch converts the ls_cb_mutex mutex to a spinlock, there is no sleepable context when this lock is held. Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2022-10-27 16:45:18 -04:00
spin_unlock(&ls->ls_cb_lock);
dlm: use workqueue for callbacks Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
2011-04-05 13:16:24 -05:00
fs: dlm: make dlm_callback_resume quite This patch makes dlm_callback_resume info printout less noisy by accumulate all callback queues into one printout not in 25 times steps. It seems this printout became lately quite noisy in relationship with gfs2. Before: [241767.849302] dlm: bin: dlm_callback_resume 25 [241767.854846] dlm: bin: dlm_callback_resume 25 [241767.860373] dlm: bin: dlm_callback_resume 25 ... [241767.865920] dlm: bin: dlm_callback_resume 25 [241767.871352] dlm: bin: dlm_callback_resume 25 [241767.876733] dlm: bin: dlm_callback_resume 25 After the patch: [ 385.485728] dlm: gfs2: dlm_callback_resume 175 if zero it will not be printed out. Reported-by: Barry Marson <bmarson@redhat.com> Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2021-11-02 15:17:14 -04:00
sum += count;
fs: dlm: use list_empty() to check last iteration This patch will use list_empty(&ls->ls_cb_delay) to check for last list iteration. In case of a multiply count of MAX_CB_QUEUE and the list is empty we do a extra goto more which we can avoid by checking on list_empty(). Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2021-11-30 14:47:14 -05:00
if (!empty) {
dlm: Don't swamp the CPU with callbacks queued during recovery Before this patch, recovery would cause all callbacks to be delayed, put on a queue, and afterward they were all queued to the callback work queue. This patch does the same thing, but occasionally takes a break after 25 of them so it won't swamp the CPU at the expense of other RT processes like corosync. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2018-11-08 14:04:50 -05:00
count = 0;
cond_resched();
goto more;
}
fs: dlm: make dlm_callback_resume quite This patch makes dlm_callback_resume info printout less noisy by accumulate all callback queues into one printout not in 25 times steps. It seems this printout became lately quite noisy in relationship with gfs2. Before: [241767.849302] dlm: bin: dlm_callback_resume 25 [241767.854846] dlm: bin: dlm_callback_resume 25 [241767.860373] dlm: bin: dlm_callback_resume 25 ... [241767.865920] dlm: bin: dlm_callback_resume 25 [241767.871352] dlm: bin: dlm_callback_resume 25 [241767.876733] dlm: bin: dlm_callback_resume 25 After the patch: [ 385.485728] dlm: gfs2: dlm_callback_resume 175 if zero it will not be printed out. Reported-by: Barry Marson <bmarson@redhat.com> Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
2021-11-02 15:17:14 -04:00
if (sum)
log_rinfo(ls, "%s %d", __func__, sum);
[DLM] The core of the DLM for GFS2/CLVM This is the core of the distributed lock manager which is required to use GFS2 as a cluster filesystem. It is also used by CLVM and can be used as a standalone lock manager independantly of either of these two projects. It implements VAX-style locking modes. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
2006-01-18 09:30:29 +00:00
}
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