Commit Graph

26 Commits

Author SHA1 Message Date
Steven Whitehouse b5d32bead1 [GFS2] Tidy up glops calls
This patch doesn't make any changes to the ordering of the various
operations related to glocking, but it does tidy up the calls to the
glops.c functions to make the structure more obvious.

The two functions: gfs2_glock_xmote_th() and gfs2_glock_drop_th() can be
made static within glock.c since they are called by every set of glock
operations. The xmote_th and drop_th glock operations are then made
conditional upon those two routines existing and called from the
previously mentioned functions in glock.c respectively.

Also it can be seen that the go_sync operation isn't needed since it can
easily be replaced by calls to xmote_bh and drop_bh respectively. This
results in no longer (confusingly) calling back into routines in glock.c
from glops.c and also reducing the glock operations by one member.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-02-05 13:37:26 -05:00
Steven Whitehouse 1c0f4872dc [GFS2] Remove local exclusive glock mode
Here is a patch for GFS2 to remove the local exclusive flag. In
the places it was used, mutex's are always held earlier in the
call path, so it appears redundant in the LM_ST_SHARED case.

Also, the GFS2 holders were setting local exclusive in any case where
the requested lock was LM_ST_EXCLUSIVE. So the other places in the glock
code where the flag was tested have been replaced with tests for the
lock state being LM_ST_EXCLUSIVE in order to ensure the logic is the
same as before (i.e. LM_ST_EXCLUSIVE is always locally exclusive as well
as globally exclusive).

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-02-05 13:37:20 -05:00
Steven Whitehouse e5dab552c8 [GFS2] Remove the "greedy" function from glock.[ch]
The "greedy" code was an attempt to retain glocks for a minimum length
of time when they relate to mmap()ed files. The current implementation
of this feature is not, however, ideal in that it required allocating
memory in order to do this and its overly complicated.

It also misses the mark by ignoring the other I/O operations which are
just as likely to suffer from the same problem. So the plan is to remove
this now and then add the functionality back as part of the glock state
machine at a later date (and thus take into account all the possible
users of this feature)

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-02-05 13:37:14 -05:00
Steven Whitehouse 3699e3a44b [GFS2] Clean up/speed up readdir
This removes the extra filldir callback which gfs2 was using to
enclose an attempt at readahead for inodes during readdir. The
code was too complicated and also hurts performance badly in the
case that the getdents64/readdir call isn't being followed by
stat() and it wasn't even getting it right all the time when it
was.

As a result, on my test box an "ls" of a directory containing 250000
files fell from about 7mins (freshly mounted, so nothing cached) to
between about 15 to 25 seconds. When the directory content was cached,
the time taken fell from about 3mins to about 4 or 5 seconds.

Interestingly in the cached case, running "ls -l" once reduced the time
taken for subsequent runs of "ls" to about 6 secs even without this
patch. Now it turns out that there was a special case of glocks being
used for prefetching the metadata, but because of the timeouts for these
locks (set to 10 secs) the metadata was being timed out before it was
being used and this the prefetch code was constantly trying to prefetch
the same data over and over.

Calling "ls -l" meant that the inodes were brought into memory and once
the inodes are cached, the glocks are not disposed of until the inodes
are pushed out of the cache, thus extending the lifetime of the glocks,
and thus bringing down the time for subsequent runs of "ls"
considerably.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-02-05 13:37:04 -05:00
Steven Whitehouse b004157ab5 [GFS2] Fix journal flush problem
This fixes a bug which resulted in poor performance due to flushing
the journal too often. The code path in question was via the inode_go_sync()
function in glops.c. The solution is not to flush the journal immediately
when inodes are ejected from memory, but batch up the work for glockd to
deal with later on. This means that glocks may now live on beyond the end of
the lifetime of their inodes (but not very much longer in the normal case).

Also fixed in this patch is a bug (which was hidden by the bug mentioned above) in
calculation of the number of free journal blocks.

The gfs2_logd process has been altered to be more responsive to the journal
filling up. We now wake it up when the number of uncommitted journal blocks
has reached the threshold level rather than trying to flush directly at the
end of each transaction. This again means doing fewer, but larger, log
flushes in general.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-11-30 10:36:42 -05:00
Steven Whitehouse 2ca99501fa [GFS2] Fix page lock/glock deadlock
This fixes a race between the glock and the page lock encountered
during truncate in gfs2_readpage and gfs2_prepare_write. The gfs2_readpages
function doesn't need the same fix since it only uses a try lock anyway, so
it will fail back to gfs2_readpage in the case of a potential deadlock.

This bug was spotted by Russell Cattelan.

Cc: Russell Cattelan <cattelan@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-11-30 10:34:43 -05:00
Steven Whitehouse c594d88664 [GFS2] Remove unused GL_DUMP flag
There is no way to set the GL_DUMP flag, and in any case the
same thing can be done with systemtap if required for debugging,
so this removes it.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-11-30 10:34:40 -05:00
Steven Whitehouse 94610610f1 [GFS2] Remove unused function from glock.c
The callback for iopen locks is unused, so this removes
it.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-09 18:59:27 -04:00
Steven Whitehouse 9b47c11d1c [GFS2] Use void * instead of typedef for locking module interface
As requested by Jan Engelhardt, this removes the typedefs in the
locking module interface and replaces them with void *. Also
since we are changing the interface, I've added a few consts
as well.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Cc: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-08 10:17:58 -04:00
Steven Whitehouse 1c089c325d [GFS2] Remove one typedef
This removes one of the typedefs from the locking interface. It
is replaced by a forward declaration of the gfs2 superblock. The
other two are not so easy to solve since in their case, they
can refer to one of two possible structures.

Cc: David Teigland <teigland@redhat.com>
Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-07 15:50:20 -04:00
Steven Whitehouse 85d1da67f7 [GFS2] Move glock hash table out of superblock
There are several reasons why we want to do this:
 - Firstly its large and thus we'll scale better with multiple
   GFS2 fs mounted at the same time
 - Secondly its easier to scale its size as required (thats a plan
   for later patches)
 - Thirdly, we can use kzalloc rather than vmalloc when allocating
   the superblock (its now only 4888 bytes)
 - Fourth its all part of my plan to eventually be able to use RCU
   with the glock hash.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-07 14:40:21 -04:00
Steven Whitehouse f2f7ba5237 [GFS2] Make headers compile on their own
As per Jan Engelhardt's comments, this should make all the headers
compile on their own by including and/or declaring structures
early.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-05 10:39:21 -04:00
Steven Whitehouse cd915493fc [GFS2] Change all types to uX style
This makes all fixed size types have consistent names.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-04 12:49:07 -04:00
Steven Whitehouse 5029996547 [GFS2] Tidy up locking code
As per Jan Engelhardt's second email, this removes some unused code,
and fixes up indenting in various places.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-04 09:49:55 -04:00
Steven Whitehouse e9fc2aa091 [GFS2] Update copyright, tidy up incore.h
As per comments from Jan Engelhardt <jengelh@linux01.gwdg.de> this
updates the copyright message to say "version" in full rather than
"v.2". Also incore.h has been updated to remove forward structure
declarations which are not required.

The gfs2_quota_lvb structure has now had endianess annotations added
to it. Also quota.c has been updated so that we now store the
lvb data locally in endian independant format to avoid needing
a structure in host endianess too. As a result the endianess
conversions are done as required at various points and thus the
conversion routines in lvb.[ch] are no longer required. I've
moved the one remaining constant in lvb.h thats used into lm.h
and removed the unused lvb.[ch].

I have not changed the HIF_ constants. That is left to a later patch
which I hope will unify the gh_flags and gh_iflags fields of the
struct gfs2_holder.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-01 11:05:15 -04:00
Steven Whitehouse 5e2b0613ed [GFS2] Remove unused code from glock layer
Remove the unused sync feature from glocks. This is currently done by
calling the required functions to sync pages/blocks directly so this
code isn't needed.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-08-30 09:38:30 -04:00
Steven Whitehouse 8fb4b536e7 [GFS2] Make glock operations const
For all the usual reasons of enforcing correctness and potentially
reducing code size, this patch makes the glock operations const.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-08-30 09:30:00 -04:00
Steven Whitehouse feaa7bba02 [GFS2] Fix unlinked file handling
This patch fixes the way we have been dealing with unlinked,
but still open files. It removes all limits (other than memory
for inodes, as per every other filesystem) on numbers of these
which we can support on GFS2. It also means that (like other
fs) its the responsibility of the last process to close the file
to deallocate the storage, rather than the person who did the
unlinking. Note that with GFS2, those two events might take place
on different nodes.

Also there are a number of other changes:

 o We use the Linux inode subsystem as it was intended to be
used, wrt allocating GFS2 inodes
 o The Linux inode cache is now the point which we use for
local enforcement of only holding one copy of the inode in
core at once (previous to this we used the glock layer).
 o We no longer use the unlinked "special" file. We just ignore it
completely. This makes unlinking more efficient.
 o We now use the 4th block allocation state. The previously unused
state is used to track unlinked but still open inodes.
 o gfs2_inoded is no longer needed
 o Several fields are now no longer needed (and removed) from the in
core struct gfs2_inode
 o Several fields are no longer needed (and removed) from the in core
superblock

There are a number of future possible optimisations and clean ups
which have been made possible by this patch.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-06-14 15:32:57 -04:00
Steven Whitehouse 320dd101e2 [GFS2] glock debugging and inode cache changes
This adds some extra debugging to glock.c and changes
inode.c's deallocation code to call the debugging code
at a suitable moment. I'm chasing down a particular bug
to do with deallocation at the moment and the code can
go again once the bug is fixed.

Also this includes the first part of some changes to unify
the Linux struct inode and GFS2's struct gfs2_inode. This
transformation will happen in small parts over the next short
period.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-18 16:25:27 -04:00
Steven Whitehouse 3a8a9a1034 [GFS2] Update copyright date to 2006
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-05-18 15:09:15 -04:00
Adrian Bunk 08bc2dbc73 [GFS2] [-mm patch] fs/gfs2/: possible cleanups
This patch contains the following possible cleanups:
- make needlessly global code static
- #if 0 unused functions
- remove the following global function that was both unused and
  unimplemented:
  - super.c: gfs2_do_upgrade()

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-28 10:59:12 -04:00
Steven Whitehouse 579b78a43b [GFS2] Remove GL_NEVER_RECURSE flag
There is no point in keeping this flag since recursion is not
now allowed for any glock.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-26 14:58:26 -04:00
Steven Whitehouse 190562bd84 [GFS2] Fix a bug: scheduling under a spinlock
At some stage, a mutex was added to gfs2_glock_put() without
checking all its call sites. Two of them were called from
under a spinlock causing random delays at various points and
crashes.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-20 16:57:23 -04:00
Steven Whitehouse fe1bdedc6c [GFS2] Use vmalloc() in dir code
When allocating memory to sort directory entries, use vmalloc()
rather than kmalloc() since for larger directories, the required
size can easily be graeter than the 128k maximum of kmalloc().

Also adding the first steps towards getting the AOP_TRUNCATED_PAGE
return code get in the glock code by flagging all places where we
request a glock and we are holding a page lock.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-04-18 10:09:15 -04:00
Steven Whitehouse d0dc80dbaf [GFS2] Update debugging code
Update the debugging code in trans.c and at the same time improve
the debugging code for gfs2_holders. The new code should be pretty
fast during the normal case and provide just as much information
in case of errors (or more).

One small function from glock.c has moved to glock.h as a static inline so
that its return address won't get in the way of the debugging.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-03-29 14:36:49 -05:00
David Teigland b3b94faa5f [GFS2] The core of GFS2
This patch contains all the core files for GFS2.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-01-16 16:50:04 +00:00