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Commit Graph

55 Commits

Author SHA1 Message Date
Dave Chinner
d0eb2f38b2 xfs: convert grant head manipulations to lockless algorithm
The only thing that the grant lock remains to protect is the grant head
manipulations when adding or removing space from the log. These calculations
are already based on atomic variables, so we can already update them safely
without locks. However, the grant head manpulations require atomic multi-step
calculations to be executed, which the algorithms currently don't allow.

To make these multi-step calculations atomic, convert the algorithms to
compare-and-exchange loops on the atomic variables. That is, we sample the old
value, perform the calculation and use atomic64_cmpxchg() to attempt to update
the head with the new value. If the head has not changed since we sampled it,
it will succeed and we are done. Otherwise, we rerun the calculation again from
a new sample of the head.

This allows us to remove the grant lock from around all the grant head space
manipulations, and that effectively removes the grant lock from the log
completely. Hence we can remove the grant lock completely from the log at this
point.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-21 12:29:14 +11:00
Dave Chinner
3f16b98507 xfs: introduce new locks for the log grant ticket wait queues
The log grant ticket wait queues are currently protected by the log
grant lock.  However, the queues are functionally independent from
each other, and operations on them only require serialisation
against other queue operations now that all of the other log
variables they use are atomic values.

Hence, we can make them independent of the grant lock by introducing
new locks just to protect the lists operations. because the lists
are independent, we can use a lock per list and ensure that reserve
and write head queuing do not contend.

To ensure forced shutdowns work correctly in conjunction with the
new fast paths, ensure that we check whether the log has been shut
down in the grant functions once we hold the relevant spin locks but
before we go to sleep. This is needed to co-ordinate correctly with
the wakeups that are issued on the ticket queues so we don't leave
any processes sleeping on the queues during a shutdown.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-21 12:29:01 +11:00
Dave Chinner
c8a09ff8ca xfs: convert log grant heads to atomic variables
Convert the log grant heads to atomic64_t types in preparation for
converting the accounting algorithms to atomic operations. his patch
just converts the variables; the algorithmic changes are in a
separate patch for clarity.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-04 00:02:40 +11:00
Dave Chinner
1c3cb9ec07 xfs: convert l_tail_lsn to an atomic variable.
log->l_tail_lsn is currently protected by the log grant lock. The
lock is only needed for serialising readers against writers, so we
don't really need the lock if we make the l_tail_lsn variable an
atomic. Converting the l_tail_lsn variable to an atomic64_t means we
can start to peel back the grant lock from various operations.

Also, provide functions to safely crack an atomic LSN variable into
it's component pieces and to recombined the components into an
atomic variable. Use them where appropriate.

This also removes the need for explicitly holding a spinlock to read
the l_tail_lsn on 32 bit platforms.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
2010-12-21 12:28:39 +11:00
Dave Chinner
84f3c683c4 xfs: convert l_last_sync_lsn to an atomic variable
log->l_last_sync_lsn is updated in only one critical spot - log
buffer Io completion - and is protected by the grant lock here. This
requires the grant lock to be taken for every log buffer IO
completion. Converting the l_last_sync_lsn variable to an atomic64_t
means that we do not need to take the grant lock in log buffer IO
completion to update it.

This also removes the need for explicitly holding a spinlock to read
the l_last_sync_lsn on 32 bit platforms.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-03 22:11:29 +11:00
Dave Chinner
eb40a87500 xfs: use wait queues directly for the log wait queues
The log grant queues are one of the few places left using sv_t
constructs for waiting. Given we are touching this code, we should
convert them to plain wait queues. While there, convert all the
other sv_t users in the log code as well.

Seeing as this removes the last users of the sv_t type, remove the
header file defining the wrapper and the fragments that still
reference it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-21 12:09:01 +11:00
Dave Chinner
a69ed03c24 xfs: combine grant heads into a single 64 bit integer
Prepare for switching the grant heads to atomic variables by
combining the two 32 bit values that make up the grant head into a
single 64 bit variable.  Provide wrapper functions to combine and
split the grant heads appropriately for calculations and use them as
necessary.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-21 12:08:20 +11:00
Dave Chinner
1054794198 xfs: convert log grant ticket queues to list heads
The grant write and reserve queues use a roll-your-own double linked
list, so convert it to a standard list_head structure and convert
all the list traversals to use list_for_each_entry(). We can also
get rid of the XLOG_TIC_IN_Q flag as we can use the list_empty()
check to tell if the ticket is in a list or not.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-12-21 12:02:25 +11:00
Christoph Hellwig
d5689eaa0a xfs: use struct list_head for the buf cancel table
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-12-16 16:05:22 -06:00
Dave Chinner
80168676eb xfs: force background CIL push under sustained load
I have been seeing occasional pauses in transaction throughput up to
30s long under heavy parallel workloads. The only notable thing was
that the xfsaild was trying to be active during the pauses, but
making no progress. It was running exactly 20 times a second (on the
50ms no-progress backoff), and the number of pushbuf events was
constant across this time as well.  IOWs, the xfsaild appeared to be
stuck on buffers that it could not push out.

Further investigation indicated that it was trying to push out inode
buffers that were pinned and/or locked. The xfsbufd was also getting
woken at the same frequency (by the xfsaild, no doubt) to push out
delayed write buffers. The xfsbufd was not making any progress
because all the buffers in the delwri queue were pinned. This scan-
and-make-no-progress dance went one in the trace for some seconds,
before the xfssyncd came along an issued a log force, and then
things started going again.

However, I noticed something strange about the log force - there
were way too many IO's issued. 516 log buffers were written, to be
exact. That added up to 129MB of log IO, which got me very
interested because it's almost exactly 25% of the size of the log.
He delayed logging code is suppose to aggregate the minimum of 25%
of the log or 8MB worth of changes before flushing. That's what
really puzzled me - why did a log force write 129MB instead of only
8MB?

Essentially what has happened is that no CIL pushes had occurred
since the previous tail push which cleared out 25% of the log space.
That caused all the new transactions to block because there wasn't
log space for them, but they kick the xfsaild to push the tail.
However, the xfsaild was not making progress because there were
buffers it could not lock and flush, and the xfsbufd could not flush
them because they were pinned. As a result, both the xfsaild and the
xfsbufd could not move the tail of the log forward without the CIL
first committing.

The cause of the problem was that the background CIL push, which
should happen when 8MB of aggregated changes have been committed, is
being held off by the concurrent transaction commit load. The
background push does a down_write_trylock() which will fail if there
is a concurrent transaction commit holding the push lock in read
mode. With 8 CPUs all doing transactions as fast as they can, there
was enough concurrent transaction commits to hold off the background
push until tail-pushing could no longer free log space, and the halt
would occur.

It should be noted that there is no reason why it would halt at 25%
of log space used by a single CIL checkpoint. This bug could
definitely violate the "no transaction should be larger than half
the log" requirement and hence result in corruption if the system
crashed under heavy load. This sort of bug is exactly the reason why
delayed logging was tagged as experimental....

The fix is to start blocking background pushes once the threshold
has been exceeded. Rework the threshold calculations to keep the
amount of log space a CIL checkpoint can use to below that of the
AIL push threshold to avoid the problem completely.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-09-29 07:51:03 -05:00
Dave Chinner
a44f13edf0 xfs: Reduce log force overhead for delayed logging
Delayed logging adds some serialisation to the log force process to
ensure that it does not deference a bad commit context structure
when determining if a CIL push is necessary or not. It does this by
grabing the CIL context lock exclusively, then dropping it before
pushing the CIL if necessary. This causes serialisation of all log
forces and pushes regardless of whether a force is necessary or not.
As a result fsync heavy workloads (like dbench) can be significantly
slower with delayed logging than without.

To avoid this penalty, copy the current sequence from the context to
the CIL structure when they are swapped. This allows us to do
unlocked checks on the current sequence without having to worry
about dereferencing context structures that may have already been
freed. Hence we can remove the CIL context locking in the forcing
code and only call into the push code if the current context matches
the sequence we need to force.

By passing the sequence into the push code, we can check the
sequence again once we have the CIL lock held exclusive and abort if
the sequence has already been pushed. This avoids a lock round-trip
and unnecessary CIL pushes when we have racing push calls.

The result is that the regression in dbench performance goes away -
this change improves dbench performance on a ramdisk from ~2100MB/s
to ~2500MB/s. This compares favourably to not using delayed logging
which retuns ~2500MB/s for the same workload.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-08-24 11:40:03 +10:00
Dave Chinner
df806158b0 xfs: enable background pushing of the CIL
If we let the CIL grow without bound, it will grow large enough to violate
recovery constraints (must be at least one complete transaction in the log at
all times) or take forever to write out through the log buffers. Hence we need
a check during asynchronous transactions as to whether the CIL needs to be
pushed.

We track the amount of log space the CIL consumes, so it is relatively simple
to limit it on a pure size basis. Make the limit the minimum of just under half
the log size (recovery constraint) or 8MB of log space (which is an awful lot
of metadata).

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-24 10:38:20 -05:00
Dave Chinner
71e330b593 xfs: Introduce delayed logging core code
The delayed logging code only changes in-memory structures and as
such can be enabled and disabled with a mount option. Add the mount
option and emit a warning that this is an experimental feature that
should not be used in production yet.

We also need infrastructure to track committed items that have not
yet been written to the log. This is what the Committed Item List
(CIL) is for.

The log item also needs to be extended to track the current log
vector, the associated memory buffer and it's location in the Commit
Item List. Extend the log item and log vector structures to enable
this tracking.

To maintain the current log format for transactions with delayed
logging, we need to introduce a checkpoint transaction and a context
for tracking each checkpoint from initiation to transaction
completion.  This includes adding a log ticket for tracking space
log required/used by the context checkpoint.

To track all the changes we need an io vector array per log item,
rather than a single array for the entire transaction. Using the new
log vector structure for this requires two passes - the first to
allocate the log vector structures and chain them together, and the
second to fill them out.  This log vector chain can then be passed
to the CIL for formatting, pinning and insertion into the CIL.

Formatting of the log vector chain is relatively simple - it's just
a loop over the iovecs on each log vector, but it is made slightly
more complex because we re-write the iovec after the copy to point
back at the memory buffer we just copied into.

This code also needs to pin log items. If the log item is not
already tracked in this checkpoint context, then it needs to be
pinned. Otherwise it is already pinned and we don't need to pin it
again.

The only other complexity is calculating the amount of new log space
the formatting has consumed. This needs to be accounted to the
transaction in progress, and the accounting is made more complex
becase we need also to steal space from it for log metadata in the
checkpoint transaction. Calculate all this at insert time and update
all the tickets, counters, etc correctly.

Once we've formatted all the log items in the transaction, attach
the busy extents to the checkpoint context so the busy extents live
until checkpoint completion and can be processed at that point in
time. Transactions can then be freed at this point in time.

Now we need to issue checkpoints - we are tracking the amount of log space
used by the items in the CIL, so we can trigger background checkpoints when the
space usage gets to a certain threshold. Otherwise, checkpoints need ot be
triggered when a log synchronisation point is reached - a log force event.

Because the log write code already handles chained log vectors, writing the
transaction is trivial, too. Construct a transaction header, add it
to the head of the chain and write it into the log, then issue a
commit record write. Then we can release the checkpoint log ticket
and attach the context to the log buffer so it can be called during
Io completion to complete the checkpoint.

We also need to allow for synchronising multiple in-flight
checkpoints. This is needed for two things - the first is to ensure
that checkpoint commit records appear in the log in the correct
sequence order (so they are replayed in the correct order). The
second is so that xfs_log_force_lsn() operates correctly and only
flushes and/or waits for the specific sequence it was provided with.

To do this we need a wait variable and a list tracking the
checkpoint commits in progress. We can walk this list and wait for
the checkpoints to change state or complete easily, an this provides
the necessary synchronisation for correct operation in both cases.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-24 10:38:03 -05:00
Dave Chinner
955833cf2a xfs: make the log ticket ID available outside the log infrastructure
The ticket ID is needed to uniquely identify transactions when doing busy
extent matching. Delayed logging changes the lifecycle of busy extents with
respect to the transaction structure lifecycle. Hence we can no longer use
the transaction structure as a means of determining the owner of the busy
extent as it may be freed and reused while the busy extent is still active.

This commit provides the infrastructure to access the xlog_tid_t held in the
ticket from a transaction handle. This avoids the need for callers to peek
into the transaction and log structures to find this out.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-24 10:33:52 -05:00
Alex Elder
48389ef175 xfs: kill off l_sectbb_mask
There remains only one user of the l_sectbb_mask field in the log
structure.  Just kill it off and compute the mask where needed from
the power-of-2 sector size.

(Only update from last post is to accomodate the changes in the
previous patch in the series.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:16 -05:00
Alex Elder
69ce58f08a xfs: record log sector size rather than log2(that)
Change struct log so it keeps track of the size (in basic blocks) of
a log sector in l_sectBBsize rather than the log-base-2 of that
value (previously, l_sectbb_log).  The name was chosen for
consistency with the other fields in the structure that represent
a number of basic blocks.

(Updated so that a variable used in computing and verifying a log's
sector size is named "log2_size".  Also added the "BB" to the
structure field name, based on feedback from Eric Sandeen.  Also
dropped some superfluous parentheses.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
2010-05-19 09:58:15 -05:00
Christoph Hellwig
e6b1f27370 xfs: clean up xlog_write_adv_cnt
Replace the awkward xlog_write_adv_cnt with an inline helper that makes
it more obvious that it's modifying it's paramters, and replace the use
of an integer type for "ptr" with a real void pointer.  Also move
xlog_write_adv_cnt to xfs_log_priv.h as it will be used outside of
xfs_log.c in the delayed logging series.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:10 -05:00
Eric Sandeen
5d77c0dc0c xfs: make several more functions static
Just minor housekeeping, a lot more functions can be trivially made
static; others could if we reordered things a bit...

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:31:38 -06:00
Christoph Hellwig
0b1b213fcf xfs: event tracing support
Convert the old xfs tracing support that could only be used with the
out of tree kdb and xfsidbg patches to use the generic event tracer.

To use it make sure CONFIG_EVENT_TRACING is enabled and then enable
all xfs trace channels by:

   echo 1 > /sys/kernel/debug/tracing/events/xfs/enable

or alternatively enable single events by just doing the same in one
event subdirectory, e.g.

   echo 1 > /sys/kernel/debug/tracing/events/xfs/xfs_ihold/enable

or set more complex filters, etc. In Documentation/trace/events.txt
all this is desctribed in more detail.  To reads the events do a

   cat /sys/kernel/debug/tracing/trace

Compared to the last posting this patch converts the tracing mostly to
the one tracepoint per callsite model that other users of the new
tracing facility also employ.  This allows a very fine-grained control
of the tracing, a cleaner output of the traces and also enables the
perf tool to use each tracepoint as a virtual performance counter,
     allowing us to e.g. count how often certain workloads git various
     spots in XFS.  Take a look at

    http://lwn.net/Articles/346470/

for some examples.

Also the btree tracing isn't included at all yet, as it will require
additional core tracing features not in mainline yet, I plan to
deliver it later.

And the really nice thing about this patch is that it actually removes
many lines of code while adding this nice functionality:

 fs/xfs/Makefile                |    8
 fs/xfs/linux-2.6/xfs_acl.c     |    1
 fs/xfs/linux-2.6/xfs_aops.c    |   52 -
 fs/xfs/linux-2.6/xfs_aops.h    |    2
 fs/xfs/linux-2.6/xfs_buf.c     |  117 +--
 fs/xfs/linux-2.6/xfs_buf.h     |   33
 fs/xfs/linux-2.6/xfs_fs_subr.c |    3
 fs/xfs/linux-2.6/xfs_ioctl.c   |    1
 fs/xfs/linux-2.6/xfs_ioctl32.c |    1
 fs/xfs/linux-2.6/xfs_iops.c    |    1
 fs/xfs/linux-2.6/xfs_linux.h   |    1
 fs/xfs/linux-2.6/xfs_lrw.c     |   87 --
 fs/xfs/linux-2.6/xfs_lrw.h     |   45 -
 fs/xfs/linux-2.6/xfs_super.c   |  104 ---
 fs/xfs/linux-2.6/xfs_super.h   |    7
 fs/xfs/linux-2.6/xfs_sync.c    |    1
 fs/xfs/linux-2.6/xfs_trace.c   |   75 ++
 fs/xfs/linux-2.6/xfs_trace.h   | 1369 +++++++++++++++++++++++++++++++++++++++++
 fs/xfs/linux-2.6/xfs_vnode.h   |    4
 fs/xfs/quota/xfs_dquot.c       |  110 ---
 fs/xfs/quota/xfs_dquot.h       |   21
 fs/xfs/quota/xfs_qm.c          |   40 -
 fs/xfs/quota/xfs_qm_syscalls.c |    4
 fs/xfs/support/ktrace.c        |  323 ---------
 fs/xfs/support/ktrace.h        |   85 --
 fs/xfs/xfs.h                   |   16
 fs/xfs/xfs_ag.h                |   14
 fs/xfs/xfs_alloc.c             |  230 +-----
 fs/xfs/xfs_alloc.h             |   27
 fs/xfs/xfs_alloc_btree.c       |    1
 fs/xfs/xfs_attr.c              |  107 ---
 fs/xfs/xfs_attr.h              |   10
 fs/xfs/xfs_attr_leaf.c         |   14
 fs/xfs/xfs_attr_sf.h           |   40 -
 fs/xfs/xfs_bmap.c              |  507 +++------------
 fs/xfs/xfs_bmap.h              |   49 -
 fs/xfs/xfs_bmap_btree.c        |    6
 fs/xfs/xfs_btree.c             |    5
 fs/xfs/xfs_btree_trace.h       |   17
 fs/xfs/xfs_buf_item.c          |   87 --
 fs/xfs/xfs_buf_item.h          |   20
 fs/xfs/xfs_da_btree.c          |    3
 fs/xfs/xfs_da_btree.h          |    7
 fs/xfs/xfs_dfrag.c             |    2
 fs/xfs/xfs_dir2.c              |    8
 fs/xfs/xfs_dir2_block.c        |   20
 fs/xfs/xfs_dir2_leaf.c         |   21
 fs/xfs/xfs_dir2_node.c         |   27
 fs/xfs/xfs_dir2_sf.c           |   26
 fs/xfs/xfs_dir2_trace.c        |  216 ------
 fs/xfs/xfs_dir2_trace.h        |   72 --
 fs/xfs/xfs_filestream.c        |    8
 fs/xfs/xfs_fsops.c             |    2
 fs/xfs/xfs_iget.c              |  111 ---
 fs/xfs/xfs_inode.c             |   67 --
 fs/xfs/xfs_inode.h             |   76 --
 fs/xfs/xfs_inode_item.c        |    5
 fs/xfs/xfs_iomap.c             |   85 --
 fs/xfs/xfs_iomap.h             |    8
 fs/xfs/xfs_log.c               |  181 +----
 fs/xfs/xfs_log_priv.h          |   20
 fs/xfs/xfs_log_recover.c       |    1
 fs/xfs/xfs_mount.c             |    2
 fs/xfs/xfs_quota.h             |    8
 fs/xfs/xfs_rename.c            |    1
 fs/xfs/xfs_rtalloc.c           |    1
 fs/xfs/xfs_rw.c                |    3
 fs/xfs/xfs_trans.h             |   47 +
 fs/xfs/xfs_trans_buf.c         |   62 -
 fs/xfs/xfs_vnodeops.c          |    8
 70 files changed, 2151 insertions(+), 2592 deletions(-)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2009-12-14 23:08:16 -06:00
Eric Sandeen
d96f8f891f xfs: add more statics & drop some unused functions
A lot more functions could be made static, but they need
forward declarations; this does some easy ones, and also
found a few unused functions in the process.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-31 14:46:20 -05:00
Christoph Hellwig
076e6acb8f xfs: cleanup xlog_bread
Most callers of xlog_bread need to call xlog_align to get the actual offset.
Consolidate that call into the main xlog_bread and provide a _xlog_bread
for those few that don't want the actual offset.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2009-03-16 08:24:13 +01:00
Christoph Hellwig
a568778739 xfs: remove uchar_t/ushort_t/uint_t/ulong_t types
Just another set of types obsfucating the code, remove them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2009-02-09 08:37:39 +01:00
Christoph Hellwig
b28708d6a0 [XFS] sanitize xlog_in_core_t definition
Move all fields from xlog_iclog_fields_t into xlog_in_core_t instead of having
them in a substructure and the using #defines to make it look like they were
directly in xlog_in_core_t.  Also document that xlog_in_core_2_t is grossly
misnamed, and make all references to it typesafe.

(First sent on Semptember 15th)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
2008-12-01 11:37:25 +11:00
Dave Chinner
cc09c0dc57 [XFS] Fix double free of log tickets
When an I/O error occurs during an intermediate commit on a rolling
transaction, xfs_trans_commit() will free the transaction structure
and the related ticket. However, the duplicate transaction that
gets used as the transaction continues still contains a pointer
to the ticket. Hence when the duplicate transaction is cancelled
and freed, we free the ticket a second time.

Add reference counting to the ticket so that we hold an extra
reference to the ticket over the transaction commit. We drop the
extra reference once we have checked that the transaction commit
did not return an error, thus avoiding a double free on commit
error.

Credit to Nick Piggin for tripping over the problem.

SGI-PV: 989741

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-11-17 17:37:10 +11:00
David Chinner
a9c21c1b9d [XFS] Given the log a pointer to the AIL
When we need to go from the log to the AIL, we have to go via the
xfs_mount. Add a xfs_ail pointer to the log so we can go directly to the
AIL associated with the log.

SGI-PV: 988143

SGI-Modid: xfs-linux-melb:xfs-kern:32351a

Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
2008-10-30 17:39:35 +11:00
Lachlan McIlroy
31bd61f2bb [XFS] Move memory allocations for log tracing out of the critical path
Memory allocations for log->l_grant_trace and iclog->ic_trace are done on
demand when the first event is logged. In xlog_state_get_iclog_space() we
call xlog_trace_iclog() under a spinlock and allocating memory here can
cause us to sleep with a spinlock held and deadlock the system.

For the log grant tracing we use KM_NOSLEEP but that means we can lose
trace entries. Since there is no locking to serialize the log grant
tracing we could race and have multiple allocations and leak memory.

So move the allocations to where we initialize the log/iclog structures.
Use KM_NOFS to avoid recursing into the filesystem and drop log->l_trace
since it's not even used.

SGI-PV: 983738

SGI-Modid: xfs-linux-melb:xfs-kern:31896a

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
2008-09-17 16:45:37 +10:00
Christoph Hellwig
4249023a5d [XFS] cleanup xfs_mountfs
Remove all the useless flags and code keyed off it in xfs_mountfs.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31831a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-08-13 16:49:32 +10:00
David Chinner
12017faf38 [XFS] clean up stale references to semaphores
A lot of code has been converted away from semaphores, but there are still
comments that reference semaphore behaviour. The log code is the worst
offender. Update the comments to reflect what the code really does now.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31814a

Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-08-13 16:34:31 +10:00
Matthew Wilcox
d748c62367 [XFS] Convert l_flushsema to a sv_t
The l_flushsema doesn't exactly have completion semantics, nor mutex
semantics. It's used as a list of tasks which are waiting to be notified
that a flush has completed. It was also being used in a way that was
potentially racy, depending on the semaphore implementation.

By using a sv_t instead of a semaphore we avoid the need for a separate
counter, since we know we just need to wake everything on the queue.

Original waitqueue implementation from Matthew Wilcox. Cleanup and
conversion to sv_t by Christoph Hellwig.

SGI-PV: 981507
SGI-Modid: xfs-linux-melb:xfs-kern:31059a

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-07-28 16:58:12 +10:00
David Chinner
4679b2d36d [XFS] Reorganise xlog_t for better cacheline isolation of contention
To reduce contention on the log in large CPU count, separate out different
parts of the xlog_t structure onto different cachelines. Move each lock
onto a different cacheline along with all the members that are
accessed/modified while that lock is held.

Also, move the debugging code into debug code.

SGI-PV: 978729
SGI-Modid: xfs-linux-melb:xfs-kern:30772a

Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-04-18 11:50:53 +10:00
David Chinner
eb01c9cd87 [XFS] Remove the xlog_ticket allocator
The ticket allocator is just a simple slab implementation internal to the
log. It requires the icloglock to be held when manipulating it and this
contributes to contention on that lock.

Just kill the entire allocator and use a memory zone instead. While there,
allow us to gracefully fail allocation with ENOMEM.

SGI-PV: 978729
SGI-Modid: xfs-linux-melb:xfs-kern:30771a

Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-04-18 11:50:39 +10:00
David Chinner
114d23aae5 [XFS] Per iclog callback chain lock
Rather than use the icloglock for protecting the iclog completion callback
chain, use a new per-iclog lock so that walking the callback chain doesn't
require holding a global lock.

This reduces contention on the icloglock during transaction commit and log
I/O completion by reducing the number of times we need to hold the global
icloglock during these operations.

SGI-PV: 978729
SGI-Modid: xfs-linux-melb:xfs-kern:30770a

Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-04-18 11:50:22 +10:00
David Chinner
155cc6b784 [XFS] Use atomics for iclog reference counting
Now that we update the log tail LSN less frequently on transaction
completion, we pass the contention straight to the global log state lock
(l_iclog_lock) during transaction completion.

We currently have to take this lock to decrement the iclog reference
count. there is a reference count on each iclog, so we need to take he
global lock for all refcount changes.

When large numbers of processes are all doing small trnasctions, the iclog
reference counts will be quite high, and the state change that absolutely
requires the l_iclog_lock is the except rather than the norm.

Change the reference counting on the iclogs to use atomic_inc/dec so that
we can use atomic_dec_and_lock during transaction completion and avoid the
need for grabbing the l_iclog_lock for every reference count decrement
except the one that matters - the last.

SGI-PV: 975671
SGI-Modid: xfs-linux-melb:xfs-kern:30505a

Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-04-18 11:38:10 +10:00
Eric Sandeen
6211870992 [XFS] remove shouting-indirection macros from xfs_sb.h
Remove macro-to-small-function indirection from xfs_sb.h, and remove some
which are completely unused.

SGI-PV: 976035
SGI-Modid: xfs-linux-melb:xfs-kern:30528a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-04-10 16:24:45 +10:00
Christoph Hellwig
b53e675dc8 [XFS] xlog_rec_header/xlog_rec_ext_header endianess annotations
Mostly trivial conversion with one exceptions: h_num_logops was kept in
native endian previously and only converted to big endian in xlog_sync,
but we always keep it big endian now. With todays cpus fast byteswap
instructions that's not an issue but the new variant keeps the code clean
and maintainable.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29821a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2008-02-07 18:11:47 +11:00
Christoph Hellwig
67fcb7bfb6 [XFS] clean up some xfs_log_priv.h macros
- the various assign lsn macros are replaced by a single inline,
xlog_assign_lsn, which is equivalent to ASSIGN_ANY_LSN_HOST except
for a more sane calling convention. ASSIGN_LSN_DISK is replaced
by xlog_assign_lsn and a manual bytespap, and ASSIGN_LSN by the same,
except we pass the cycle and block arguments explicitly instead of a
log paramter. The latter two variants only had 2, respectively one
user anyway.
- the GET_CYCLE is replaced by a xlog_get_cycle inline with exactly the
same calling conventions.
- GET_CLIENT_ID is replaced by xlog_get_client_id which leaves away
the unused arch argument. Instead of conditional defintions
depending on host endianess we now do an unconditional swap and shift
then, which generates equal code.
- the unused XLOG_SET macro is removed.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29820a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2008-02-07 18:11:38 +11:00
Christoph Hellwig
03bea6fe6c [XFS] clean up some xfs_log_priv.h macros
- the various assign lsn macros are replaced by a single inline,
xlog_assign_lsn, which is equivalent to ASSIGN_ANY_LSN_HOST except
for a more sane calling convention. ASSIGN_LSN_DISK is replaced
by xlog_assign_lsn and a manual bytespap, and ASSIGN_LSN by the same,
except we pass the cycle and block arguments explicitly instead of a
log paramter. The latter two variants only had 2, respectively one
user anyway.
- the GET_CYCLE is replaced by a xlog_get_cycle inline with exactly the
same calling conventions.
- GET_CLIENT_ID is replaced by xlog_get_client_id which leaves away
the unused arch argument. Instead of conditional defintions
depending on host endianess we now do an unconditional swap and shift
then, which generates equal code.
- the unused XLOG_SET macro is removed.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29819a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2008-02-07 18:10:31 +11:00
Eric Sandeen
c8b5ea289f [XFS] Unwrap GRANT_LOCK.
Un-obfuscate GRANT_LOCK, remove GRANT_LOCK->mutex_lock->spin_lock macros,
call spin_lock directly, remove extraneous cookie holdover from old xfs
code, and change lock type to spinlock_t.

SGI-PV: 970382
SGI-Modid: xfs-linux-melb:xfs-kern:29741a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2008-02-07 16:44:41 +11:00
Eric Sandeen
b22cd72c95 [XFS] Unwrap LOG_LOCK.
Un-obfuscate LOG_LOCK, remove LOG_LOCK->mutex_lock->spin_lock macros, call
spin_lock directly, remove extraneous cookie holdover from old xfs code,
and change lock type to spinlock_t.

SGI-PV: 970382
SGI-Modid: xfs-linux-melb:xfs-kern:29740a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2008-02-07 16:44:32 +11:00
Christoph Hellwig
0adba5363c [XFS] replace some large xfs_log_priv.h macros by proper functions
... or in the case of XLOG_TIC_ADD_OPHDR remove a useless macro entirely.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29511a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-10-16 12:17:56 +10:00
Eric Sandeen
dcb3b83feb [XFS] clean up xfs_start_flags
xfs_start_flags can make use of is_power_of_2 to tidy up the test a little
bit.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29327a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-10-15 16:42:18 +10:00
Eric Sandeen
1cb5125875 [XFS] choose single default logbuf count & size
Remove sizing of logbuf size & count based on physical memory; this was
never a very good gauge as it's looking at global memory, but deciding on
sizing per-filesystem; no account is made of the total number of
filesystems, for example.

For now just take the largest "default" case, as was set for machines with
>400MB - 8 x 32k buffers. This can always be tuned higher or lower with
mount options if necessary. Removes one more user of xfs_physmem.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29323a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2007-10-15 16:38:23 +10:00
Tim Shimmin
955e47ad28 [XFS] Fixes the leak in reservation space because we weren't ungranting
space for the unmount record - which becomes a problem in the freeze/thaw
scenario.

SGI-PV: 942533
SGI-Modid: xfs-linux-melb:xfs-kern:26815a

Signed-off-by: Tim Shimmin <tes@sgi.com>
2006-09-28 11:04:16 +10:00
Eric Sandeen
3f89243c5b [XFS] Remove several macros that are no longer used anywhere
SGI-PV: 955302
SGI-Modid: xfs-linux-melb:xfs-kern:26749a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
2006-09-28 11:02:57 +10:00
Tim Shimmin
1259845d3f [XFS] remove XFS_LOG_RES_DEBUG and turn on the res history all the time to
get more useful error info on space for trans items

SGI-PV: 947110
SGI-Modid: xfs-linux-melb:xfs-kern:24886a

Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-01-11 21:02:47 +11:00
Christoph Hellwig
dd954c69d1 [XFS] turn xlog helper macros into real functions
SGI-PV: 946205
SGI-Modid: xfs-linux-melb:xfs-kern:203360a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-01-11 15:34:50 +11:00
Eric Sandeen
65be605419 [XFS] remove unused "readonly" arg from xlog_find_tail and xlog_recover
SGI-PV: 946611
SGI-Modid: xfs-linux-melb:xfs-kern:203307a

Signed-off-by: Eric Sandeen <sandeen@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
2006-01-11 15:34:19 +11:00
Nathan Scott
551c81e2d3 [XFS] Resolve the xlog_grant_log_space hang, revert inline to macro.
SGI-PV: 946205
SGI-Modid: xfs-linux-melb:xfs-kern:24567a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-25 16:42:28 +11:00
Nathan Scott
cfcbbbd089 [XFS] Remove old, broken nolog-mode code - noone plans to ever fix it.
SGI-PV: 944821
SGI-Modid: xfs-linux:xfs-kern:24213a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02 15:12:04 +11:00
Nathan Scott
7b71876980 [XFS] Update license/copyright notices to match the prefered SGI
boilerplate.

SGI-PV: 913862
SGI-Modid: xfs-linux:xfs-kern:23903a

Signed-off-by: Nathan Scott <nathans@sgi.com>
2005-11-02 14:58:39 +11:00