11 Jan, 2012
1 commit
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This new method of managing recovery is an alternative to
the previous approach of using the userland gfs_controld.- use dlm slot numbers to assign journal id's
- use dlm recovery callbacks to initiate journal recovery
- use a dlm lock to determine the first node to mount fs
- use a dlm lock to track journals that need recoverySigned-off-by: David Teigland
Signed-off-by: Steven Whitehouse
22 Nov, 2011
1 commit
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This patch separates the code pertaining to allocations into two
parts: quota-related information and block reservations.
This patch also moves all the block reservation structure allocations to
function gfs2_inplace_reserve to simplify the code, and moves
the frees to function gfs2_inplace_release.Signed-off-by: Bob Peterson
Signed-off-by: Steven Whitehouse
27 Jul, 2011
1 commit
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This allows us to move duplicated code in
(atomic_inc_not_zero() for now) toSigned-off-by: Arun Sharma
Reviewed-by: Eric Dumazet
Cc: Ingo Molnar
Cc: David Miller
Cc: Eric Dumazet
Acked-by: Mike Frysinger
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
15 Jul, 2011
1 commit
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This patch adds a cache for the hash table to the directory code
in order to help simplify the way in which the hash table is
accessed. This is intended to be a first step towards introducing
some performance improvements in the directory code.There are two follow ups that I'm hoping to see fairly shortly. One
is to simplify the hash table reading code now that we always read the
complete hash table, whether we want one entry or all of them. The
other is to introduce readahead on the heads of the hash chains
which are referred to from the table.The hash table is a maximum of 128k in size, so it is not worth trying
to read it in small chunks.Signed-off-by: Steven Whitehouse
27 May, 2011
1 commit
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* 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
gfs2: Drop __TIME__ usage
isdn/diva: Drop __TIME__ usage
atm: Drop __TIME__ usage
dlm: Drop __TIME__ usage
wan/pc300: Drop __TIME__ usage
parport: Drop __TIME__ usage
hdlcdrv: Drop __TIME__ usage
baycom: Drop __TIME__ usage
pmcraid: Drop __DATE__ usage
edac: Drop __DATE__ usage
rio: Drop __DATE__ usage
scsi/wd33c93: Drop __TIME__ usage
scsi/in2000: Drop __TIME__ usage
aacraid: Drop __TIME__ usage
media/cx231xx: Drop __TIME__ usage
media/radio-maxiradio: Drop __TIME__ usage
nozomi: Drop __TIME__ usage
cyclades: Drop __TIME__ usage
26 May, 2011
1 commit
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The kernel already prints its build timestamp during boot, no need to
repeat it in random drivers and produce different object files each
time.Cc: Steven Whitehouse
Cc: cluster-devel@redhat.com
Signed-off-by: Michal Marek
20 Apr, 2011
1 commit
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The GLF_LRU flag introduced in the previous patch can be
used to check if a glock is on the lru list when a new
holder is queued and if so remove it, without having first
to get the lru_lock.The main purpose of this patch however is to optimise the
glocks left over when an inode at end of life is being
evicted. Previously such glocks were left with the GLF_LFLUSH
flag set, so that when reclaimed, each one required a log flush.
This patch resets the GLF_LFLUSH flag when there is nothing
left to flush thus preventing later log flushes as glocks are
reused or demoted.In order to do this, we need to keep track of the number of
revokes which are outstanding, and also to clear the GLF_LFLUSH
bit after a log commit when only revokes have been processed.Signed-off-by: Steven Whitehouse
16 Mar, 2011
1 commit
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* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw:
GFS2: Don't use _raw version of RCU dereference
GFS2: Adding missing unlock_page()
GFS2: Update to AIL list locking
GFS2: introduce AIL lock
GFS2: fix block allocation check for fallocate
GFS2: Optimize glock multiple-dequeue code
GFS2: Remove potential race in flock code
GFS2: Fix glock deallocation race
GFS2: quota allows exceeding hard limit
GFS2: deallocation performance patch
GFS2: panics on quotacheck update
GFS2: Improve cluster mmap scalability
GFS2: Fix glock queue trace point
GFS2: Post-VFS scale update for RCU path walk
GFS2: Use RCU for glock hash table
24 Feb, 2011
1 commit
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Michael Leun reported that running parallel opens on a fuse filesystem
can trigger a "kernel BUG at mm/truncate.c:475"Gurudas Pai reported the same bug on NFS.
The reason is, unmap_mapping_range() is not prepared for more than
one concurrent invocation per inode. For example:thread1: going through a big range, stops in the middle of a vma and
stores the restart address in vm_truncate_count.thread2: comes in with a small (e.g. single page) unmap request on
the same vma, somewhere before restart_address, finds that the
vma was already unmapped up to the restart address and happily
returns without doing anything.Another scenario would be two big unmap requests, both having to
restart the unmapping and each one setting vm_truncate_count to its
own value. This could go on forever without any of them being able to
finish.Truncate and hole punching already serialize with i_mutex. Other
callers of unmap_mapping_range() do not, and it's difficult to get
i_mutex protection for all callers. In particular ->d_revalidate(),
which calls invalidate_inode_pages2_range() in fuse, may be called
with or without i_mutex.This patch adds a new mutex to 'struct address_space' to prevent
running multiple concurrent unmap_mapping_range() on the same mapping.[ We'll hopefully get rid of all this with the upcoming mm
preemptibility series by Peter Zijlstra, the "mm: Remove i_mmap_mutex
lockbreak" patch in particular. But that is for 2.6.39 ]Signed-off-by: Miklos Szeredi
Reported-by: Michael Leun
Reported-by: Gurudas Pai
Tested-by: Gurudas Pai
Acked-by: Hugh Dickins
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds
17 Feb, 2011
1 commit
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There are two spellings in use for 'freeze' + 'able' - 'freezable' and
'freezeable'. The former is the more prominent one. The latter is
mostly used by workqueue and in a few other odd places. Unify the
spelling to 'freezable'.Signed-off-by: Tejun Heo
Reported-by: Alan Stern
Acked-by: "Rafael J. Wysocki"
Acked-by: Greg Kroah-Hartman
Acked-by: Dmitry Torokhov
Cc: David Woodhouse
Cc: Alex Dubov
Cc: "David S. Miller"
Cc: Steven Whitehouse
21 Jan, 2011
1 commit
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This has a number of advantages:
- Reduces contention on the hash table lock
- Makes the code smaller and simpler
- Should speed up glock dumps when under load
- Removes ref count changing in examine_bucket
- No longer need hash chain lock in glock_put() in common caseThere are some further changes which this enables and which
we may do in the future. One is to look at using SLAB_RCU,
and another is to look at using a per-cpu counter for the
per-sb glock counter, since that is touched twice in the
lifetime of each glock (but only used at umount time).Signed-off-by: Steven Whitehouse
Cc: Paul E. McKenney
23 Oct, 2010
1 commit
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* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: remove in_workqueue_context()
workqueue: Clarify that schedule_on_each_cpu is synchronous
memory_hotplug: drop spurious calls to flush_scheduled_work()
shpchp: update workqueue usage
pciehp: update workqueue usage
isdn/eicon: don't call flush_scheduled_work() from diva_os_remove_soft_isr()
workqueue: add and use WQ_MEM_RECLAIM flag
workqueue: fix HIGHPRI handling in keep_working()
workqueue: add queue_work and activate_work trace points
workqueue: prepare for more tracepoints
workqueue: implement flush[_delayed]_work_sync()
workqueue: factor out start_flush_work()
workqueue: cleanup flush/cancel functions
workqueue: implement alloc_ordered_workqueue()Fix up trivial conflict in fs/gfs2/main.c as per Tejun
11 Oct, 2010
1 commit
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Add WQ_MEM_RECLAIM flag which currently maps to WQ_RESCUER, mark
WQ_RESCUER as internal and replace all external WQ_RESCUER usages to
WQ_MEM_RECLAIM.This makes the API users express the intent of the workqueue instead
of indicating the internal mechanism used to guarantee forward
progress. This is also to make it cleaner to add more semantics to
WQ_MEM_RECLAIM. For example, if deemed necessary, memory reclaim
workqueues can be made highpri.This patch doesn't introduce any functional change.
Signed-off-by: Tejun Heo
Cc: Jeff Garzik
Cc: Dave Chinner
Cc: Steven Whitehouse
20 Sep, 2010
2 commits
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Rather than calculating the qstrs for . and .. each time
we need them, its better to keep a constant version of
these and just refer to them when required.Signed-off-by: Steven Whitehouse
Reviewed-by: Christoph Hellwig -
The recovery workqueue can be freezable since
we want it to finish what it is doing if the system is to
be frozen (although why you'd want to freeze a cluster node
is beyond me since it will result in it being ejected from
the cluster). It does still make sense for single node
GFS2 filesystems though.The glock workqueue will benefit from being able to run more
work items concurrently. A test running postmark shows
improved performance and multi-threaded workloads are likely
to benefit even more. It needs to be high priority because
the latency directly affects the latency of filesystem glock
operations.The delete workqueue is similar to the recovery workqueue in
that it must not get blocked by memory allocations, and may
run for a long time.Potentially other GFS2 threads might also be converted to
workqueues, but I'll leave that for a later patch.Signed-off-by: Steven Whitehouse
Acked-by: Tejun Heo
23 Jul, 2010
1 commit
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Workqueue can now handle high concurrency. Convert gfs to use
workqueue instead of slow-work.* Steven pointed out that recovery path might be run from allocation
path and thus requires forward progress guarantee without memory
allocation. Create and use gfs_recovery_wq with rescuer. Please
note that forward progress wasn't guaranteed with slow-work.* Updated to use non-reentrant workqueue.
Signed-off-by: Tejun Heo
Acked-by: Steven Whitehouse
29 Mar, 2010
1 commit
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Apparently this might confuse parsers.
Reported-by: Christoph Hellwig
Signed-off-by: Steven Whitehouse
01 Mar, 2010
1 commit
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Since the start of GFS2, an "extra" inode has been used to store
the metadata belonging to each inode. The only reason for using
this inode was to have an extra address space, the other fields
were unused. This means that the memory usage was rather inefficient.The reason for keeping each inode's metadata in a separate address
space is that when glocks are requested on remote nodes, we need to
be able to efficiently locate the data and metadata which relating
to that glock (inode) in order to sync or sync and invalidate it
(depending on the remotely requested lock mode).This patch adds a new type of glock, which has in addition to
its normal fields, has an address space. This applies to all
inode and rgrp glocks (but to no other glock types which remain
as before). As a result, we no longer need to have the second
inode.This results in three major improvements:
1. A saving of approx 25% of memory used in caching inodes
2. A removal of the circular dependency between inodes and glocks
3. No confusion between "normal" and "metadata" inodes in super.cAlthough the first of these is the more immediately apparent, the
second is just as important as it now enables a number of clean
ups at umount time. Those will be the subject of future patches.Signed-off-by: Steven Whitehouse
20 Nov, 2009
1 commit
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Wait for outstanding slow work items belonging to a module to clear when
unregistering that module as a user of the facility. This prevents the put_ref
code of a work item from being taken away before it returns.Signed-off-by: David Howells
19 May, 2009
1 commit
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This patch fixes a race condition where we can receive recovery
requests part way through processing a umount. This was causing
problems since the recovery thread had already gone away.Looking in more detail at the recovery code, it was really trying
to implement a slight variation on a work queue, and that happens to
align nicely with the recently introduced slow-work subsystem. As a
result I've updated the code to use slow-work, rather than its own home
grown variety of work queue.When using the wait_on_bit() function, I noticed that the wait function
that was supplied as an argument was appearing in the WCHAN field, so
I've updated the function names in order to produce more meaningful
output.Signed-off-by: Steven Whitehouse
24 Mar, 2009
2 commits
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This is the big patch that I've been working on for some time
now. There are many reasons for wanting to make this change
such as:
o Reducing overhead by eliminating duplicated fields between structures
o Simplifcation of the code (reduces the code size by a fair bit)
o The locking interface is now the DLM interface itself as proposed
some time ago.
o Fewer lookups of glocks when processing replies from the DLM
o Fewer memory allocations/deallocations for each glock
o Scope to do further optimisations in the future (but this patch is
more than big enough for now!)Please note that (a) this patch relates to the lock_dlm module and
not the DLM itself, that is still a separate module; and (b) that
we retain the ability to build GFS2 as a standalone single node
filesystem with out requiring the DLM.This patch needs a lot of testing, hence my keeping it I restarted
my -git tree after the last merge window. That way, this has the maximum
exposure before its merged. This is (modulo a few minor bug fixes) the
same patch that I've been posting on and off the the last three months
and its passed a number of different tests so far.Signed-off-by: Steven Whitehouse
-
Deallocation of gfs2_quota_data objects now happens on-demand through a
shrinker instead of routinely deallocating through the quotad daemon.Signed-off-by: Abhijith Das
Signed-off-by: Steven Whitehouse
05 Jan, 2009
4 commits
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This patch removes the two daemons, gfs2_scand and gfs2_glockd
and replaces them with a shrinker which is called from the VM.The net result is that GFS2 responds better when there is memory
pressure, since it shrinks the glock cache at the same rate
as the VFS shrinks the dcache and icache. There are no longer
any time based criteria for shrinking glocks, they are kept
until such time as the VM asks for more memory and then we
demote just as many glocks as required.There are potential future changes to this code, including the
possibility of sorting the glocks which are to be written back
into inode number order, to get a better I/O ordering. It would
be very useful to have an elevator based workqueue implementation
for this, as that would automatically deal with the read I/O cases
at the same time.This patch is my answer to Andrew Morton's remark, made during
the initial review of GFS2, asking why GFS2 needs so many kernel
threads, the answer being that it doesn't :-) This patch is a
net loss of about 200 lines of code.Signed-off-by: Steven Whitehouse
-
Following on from the recent clean up of gfs2_quotad, this patch moves
the processing of "truncate in progress" inodes from the glock workqueue
into gfs2_quotad. This fixes a hang due to the "truncate in progress"
processing requiring glocks in order to complete.It might seem odd to use gfs2_quotad for this particular item, but
we have to use a pre-existing thread since creating a thread implies
a GFP_KERNEL memory allocation which is not allowed from the glock
workqueue context. Of the existing threads, gfs2_logd and gfs2_recoverd
may deadlock if used for this operation. gfs2_scand and gfs2_glockd are
both scheduled for removal at some (hopefully not too distant) future
point. That leaves only gfs2_quotad whose workload is generally fairly
light and is easily adapted for this extra task.Also, as a result of this change, it opens the way for a future patch to
make the reading of the inode's information asynchronous with respect to
the glock workqueue, which is another improvement that has been on the list
for some time now.Signed-off-by: Steven Whitehouse
-
This patch is a clean up of gfs2_quotad prior to giving it an
extra job to do in addition to the current portfolio of updating
the quota and statfs information from time to time.As a result it has been moved into quota.c allowing one of the
functions it calls to be made static. Also the clean up allows
the two existing functions to have separate timeouts and also
to coexist with its future role of dealing with the "truncate in
progress" inode flag.The (pointless) setting of gfs2_quotad_secs is removed since we
arrange to only wake up quotad when one of the two timers expires.In addition the struct gfs2_quota_data is moved into a slab cache,
mainly for easier debugging. It should also be possible to use
a shrinker in the future, rather than the current scheme of scanning
the quota data entries from time to time.Signed-off-by: Steven Whitehouse
-
Move the contents of some headers which contained very
little into more sensible places, and remove the original
header files. This should make it easier to find things.Signed-off-by: Steven Whitehouse
27 Jul, 2008
1 commit
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Kmem cache passed to constructor is only needed for constructors that are
themselves multiplexeres. Nobody uses this "feature", nor does anybody uses
passed kmem cache in non-trivial way, so pass only pointer to object.Non-trivial places are:
arch/powerpc/mm/init_64.c
arch/powerpc/mm/hugetlbpage.cThis is flag day, yes.
Signed-off-by: Alexey Dobriyan
Acked-by: Pekka Enberg
Acked-by: Christoph Lameter
Cc: Jon Tollefson
Cc: Nick Piggin
Cc: Matt Mackall
[akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c]
[akpm@linux-foundation.org: fix mm/slab.c]
[akpm@linux-foundation.org: fix ubifs]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 Jun, 2008
1 commit
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This patch implements a number of cleanups to the core of the
GFS2 glock code. As a result a lot of code is removed. It looks
like a really big change, but actually a large part of this patch
is either removing or moving existing code.There are some new bits too though, such as the new run_queue()
function which is considerably streamlined. Highlights of this
patch include:o Fixes a cluster coherency bug during SH -> EX lock conversions
o Removes the "glmutex" code in favour of a single bit lock
o Removes the ->go_xmote_bh() for inodes since it was duplicating
->go_lock()
o We now only use the ->lm_lock() function for both locks and
unlocks (i.e. unlock is a lock with target mode LM_ST_UNLOCKED)
o The fast path is considerably shortly, giving performance gains
especially with lock_nolock
o The glock_workqueue is now used for all the callbacks from the DLM
which allows us to simplify the lock_dlm module (see following patch)
o The way is now open to make further changes such as eliminating the two
threads (gfs2_glockd and gfs2_scand) in favour of a more efficient
scheme.This patch has undergone extensive testing with various test suites
so it should be pretty stable by now.Signed-off-by: Steven Whitehouse
Cc: Bob Peterson
31 Mar, 2008
1 commit
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This patch moves the gfs2_rgrpd structure to its own slab
memory. This makes it easier to control and monitor, and
yields less memory fragmentation.Signed-off-by: Bob Peterson
Signed-off-by: Steven Whitehouse
25 Jan, 2008
3 commits
-
This patch removes a vestigial variable "i_spin" from the gfs2_inode
structure. This not only saves us memory (>300000 of these in memory
for the oom test) it also saves us time because we don't have to
spend time initializing it (i.e. slightly better performance).Signed-off-by: Bob Peterson
Signed-off-by: Steven Whitehouse -
It is possible to reduce the size of GFS2 inodes by taking the i_alloc
structure out of the gfs2_inode. This patch allocates the i_alloc
structure whenever its needed, and frees it afterward. This decreases
the amount of low memory we use at the expense of requiring a memory
allocation for each page or partial page that we write. A quick test
with postmark shows that the overhead is not measurable and I also note
that OCFS2 use the same approach.In the future I'd like to solve the problem by shrinking down the size
of the members of the i_alloc structure, but for now, this reduces the
immediate problem of using too much low-memory on x86 and doesn't add
too much overhead.Signed-off-by: Steven Whitehouse
-
The i_cache was designed to keep references to the indirect blocks
used during block mapping so that they didn't have to be looked
up continually. The idea failed because there are too many places
where the i_cache needs to be freed, and this has in the past been
the cause of many bugs.In addition there was no performance benefit being gained since the
disk blocks in question were cached anyway. So this patch removes
it in order to simplify the code to prepare for other changes which
would otherwise have had to add further support for this feature.Signed-off-by: Steven Whitehouse
17 Oct, 2007
1 commit
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Slab constructors currently have a flags parameter that is never used. And
the order of the arguments is opposite to other slab functions. The object
pointer is placed before the kmem_cache pointer.Convert
ctor(void *object, struct kmem_cache *s, unsigned long flags)
to
ctor(struct kmem_cache *s, void *object)
throughout the kernel
[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
10 Oct, 2007
1 commit
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We only need a single gfs2_scand process rather than the one
per filesystem which we had previously. As a result the parameter
determining the frequency of gfs2_scand runs becomes a module
parameter rather than a mount parameter as it was before.Signed-off-by: Steven Whitehouse
20 Jul, 2007
1 commit
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Slab destructors were no longer supported after Christoph's
c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been
BUGs for both slab and slub, and slob never supported them
either.This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).Signed-off-by: Paul Mundt
17 May, 2007
1 commit
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SLAB_CTOR_CONSTRUCTOR is always specified. No point in checking it.
Signed-off-by: Christoph Lameter
Cc: David Howells
Cc: Jens Axboe
Cc: Steven French
Cc: Michael Halcrow
Cc: OGAWA Hirofumi
Cc: Miklos Szeredi
Cc: Steven Whitehouse
Cc: Roman Zippel
Cc: David Woodhouse
Cc: Dave Kleikamp
Cc: Trond Myklebust
Cc: "J. Bruce Fields"
Cc: Anton Altaparmakov
Cc: Mark Fasheh
Cc: Paul Mackerras
Cc: Christoph Hellwig
Cc: Jan Kara
Cc: David Chinner
Cc: "David S. Miller"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 May, 2007
2 commits
-
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw: (34 commits)
[GFS2] Uncomment sprintf_symbol calling code
[DLM] lowcomms style
[GFS2] printk warning fixes
[GFS2] Patch to fix mmap of stuffed files
[GFS2] use lib/parser for parsing mount options
[DLM] Lowcomms nodeid range & initialisation fixes
[DLM] Fix dlm_lowcoms_stop hang
[DLM] fix mode munging
[GFS2] lockdump improvements
[GFS2] Patch to detect corrupt number of dir entries in leaf and/or inode blocks
[GFS2] bz 236008: Kernel gpf doing cat /debugfs/gfs2/xxx (lock dump)
[DLM] fs/dlm/ast.c should #include "ast.h"
[DLM] Consolidate transport protocols
[DLM] Remove redundant assignment
[GFS2] Fix bz 234168 (ignoring rgrp flags)
[DLM] change lkid format
[DLM] interface for purge (2/2)
[DLM] add orphan purging code (1/2)
[DLM] split create_message function
[GFS2] Set drop_count to 0 (off) by default
... -
I have never seen a use of SLAB_DEBUG_INITIAL. It is only supported by
SLAB.I think its purpose was to have a callback after an object has been freed
to verify that the state is the constructor state again? The callback is
performed before each freeing of an object.I would think that it is much easier to check the object state manually
before the free. That also places the check near the code object
manipulation of the object.Also the SLAB_DEBUG_INITIAL callback is only performed if the kernel was
compiled with SLAB debugging on. If there would be code in a constructor
handling SLAB_DEBUG_INITIAL then it would have to be conditional on
SLAB_DEBUG otherwise it would just be dead code. But there is no such code
in the kernel. I think SLUB_DEBUG_INITIAL is too problematic to make real
use of, difficult to understand and there are easier ways to accomplish the
same effect (i.e. add debug code before kfree).There is a related flag SLAB_CTOR_VERIFY that is frequently checked to be
clear in fs inode caches. Remove the pointless checks (they would even be
pointless without removeal of SLAB_DEBUG_INITIAL) from the fs constructors.This is the last slab flag that SLUB did not support. Remove the check for
unimplemented flags from SLUB.Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 May, 2007
2 commits
-
This patch prevents the printing of a warning message in cases where
the fs is functioning normally by handing off responsibility for
unlinked, but still open inodes, to another node for eventual deallocation.
Also, there is now an improved system for ensuring that such requests
to other nodes do not get lost. The callback on the iopen lock is
only ever called when i_nlink == 0 and when a node is unable to deallocate
it due to it still being in use on another node. When a node receives
the callback therefore, it knows that i_nlink must be zero, so we mark
it as such (in gfs2_drop_inode) in order that it will then attempt
deallocation of the inode itself.As an additional benefit, queuing a demote request no longer requires
a memory allocation. This simplifies the code for dealing with gfs2_holders
as it removes one special case.There are two new fields in struct gfs2_glock. gl_demote_state is the
state which the remote node has requested and gl_demote_time is the
time when the request came in. Both fields are only valid when the
GLF_DEMOTE flag is set in gl_flags.Signed-off-by: Steven Whitehouse
-
The attached patch resolves bz 228540. This adds the capability
for gfs2 to dump gfs2 locks through the debugfs file system.
This used to exist in gfs1 as "gfs_tool lockdump" but it's missing from
gfs2 because all the ioctls were stripped out. Please see the bugzilla
for more history about the fix. This patch is also attached to the bugzilla
record.The patch is against Steve Whitehouse's latest nmw git tree kernel
(2.6.21-rc1) and has been tested on system trin-10.Signed-off-by: Robert Peterson
Signed-off-by: Steven Whitehouse