BMC/Intel-BMC/linux.git/fs/gfs2/glops.c, branch dev

GFS2: Don't brelse rgrp buffer_heads every allocation

2015-06-19T12:40:22+00:00

This patch allows the block allocation code to retain the buffers for the resource groups so they don't need to be re-read from buffer cache with every request. This is a performance improvement that's especially noticeable when resource groups are very large. For example, with 2GB resource groups and 4K blocks, there can be 33 blocks for every resource group. This patch allows those 33 buffers to be kept around and not read in and thrown away with every operation. The buffers are released when the resource group is either synced or invalidated. Signed-off-by: Bob Peterson Reviewed-by: Steven Whitehouse Reviewed-by: Benjamin Marzinski

GFS2: Don't add all glocks to the lru

2015-06-18T17:17:59+00:00

The glocks used for resource groups often come and go hundreds of thousands of times per second. Adding them to the lru list just adds unnecessary contention for the lru_lock spin_lock, especially considering we're almost certainly going to re-use the glock and take it back off the lru microseconds later. We never want the glock shrinker to cull them anyway. This patch adds a new bit in the glops that determines which glock types get put onto the lru list and which ones don't. Signed-off-by: Bob Peterson Acked-by: Steven Whitehouse

GFS2: update freeze code to use freeze/thaw_super on all nodes

2014-11-17T10:36:39+00:00

The current gfs2 freezing code is considerably more complicated than it should be because it doesn't use the vfs freezing code on any node except the one that begins the freeze. This is because it needs to acquire a cluster glock before calling the vfs code to prevent a deadlock, and without the new freeze_super and thaw_super hooks, that was impossible. To deal with the issue, gfs2 had to do some hacky locking tricks to make sure that a frozen node couldn't be holding on a lock it needed to do the unfreeze ioctl. This patch makes use of the new hooks to simply the gfs2 locking code. Now, all the nodes in the cluster freeze and thaw in exactly the same way. Every node in the cluster caches the freeze glock in the shared state. The new freeze_super hook allows the freezing node to grab this freeze glock in the exclusive state without first calling the vfs freeze_super function. All the nodes in the cluster see this lock change, and call the vfs freeze_super function. The vfs locking code guarantees that the nodes can't get stuck holding the glocks necessary to unfreeze the system. To unfreeze, the freezing node uses the new thaw_super hook to drop the freeze glock. Again, all the nodes notice this, reacquire the glock in shared mode and call the vfs thaw_super function. Signed-off-by: Benjamin Marzinski Signed-off-by: Steven Whitehouse

GFS2: use _RET_IP_ instead of (unsigned long)__builtin_return_address(0)

2014-10-08T08:57:07+00:00

use macro definition Signed-off-by: Fabian Frederick Signed-off-by: Steven Whitehouse

GFS2: memcontrol: Spelling s/invlidate/invalidate/

2014-07-18T10:14:31+00:00

Signed-off-by: Geert Uytterhoeven Cc: cluster-devel@redhat.com Signed-off-by: Steven Whitehouse

Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw into next

2014-06-04T15:30:10+00:00

Pull gfs2 updates from Steven Whitehouse: "This must be about the smallest merge window patch set ever for GFS2. It is probably also the first one without a single patch from me. That is down to a combination of factors, and I have some things in the works that are not quite ready yet, that I hope to put in next time around. Returning to what is here this time... we have 3 patches which fix various warnings. Two are bug fixes (for quotas and also a rare recovery race condition). The final patch, from Ben Marzinski, is an important change in the freeze code which has been in progress for some time. This removes the need to take and drop the transaction lock for every single transaction, when the only time it was used, was at file system freeze time. Ben's patch integrates the freeze operation into the journal flush code as an alternative with lower overheads and also lands up resolving some difficult to fix races at the same time" * tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw: GFS2: Prevent recovery before the local journal is set GFS2: fs/gfs2/file.c: kernel-doc warning fixes GFS2: fs/gfs2/bmap.c: kernel-doc warning fixes GFS2: remove transaction glock GFS2: lops.c: replace 0 by NULL for pointers GFS2: quotas not being refreshed in gfs2_adjust_quota

GFS2: remove transaction glock

2014-05-14T09:04:34+00:00

GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski Signed-off-by: Steven Whitehouse

arch: Mass conversion of smp_mb__*()

2014-04-18T12:20:48+00:00

Mostly scripted conversion of the smp_mb__* barriers. Signed-off-by: Peter Zijlstra Acked-by: Paul E. McKenney Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org Cc: Linus Torvalds Cc: linux-arch@vger.kernel.org Signed-off-by: Ingo Molnar

GFS2: Move log buffer lists into transaction

2014-02-24T16:54:54+00:00

Over time, we hope to be able to improve the concurrency available in the log code. This is one small step towards that, by moving the buffer lists from the super block, and into the transaction structure, so that each transaction builds its own buffer lists. At transaction commit time, the buffer lists are merged into the currently accumulating transaction. That transaction then is passed into the before and after commit functions at journal flush time. Thus there should be no change in overall behaviour yet. Signed-off-by: Steven Whitehouse

GFS2: Don't use ENOBUFS when ENOMEM is the correct error code

2014-01-16T10:31:13+00:00

Al Viro has tactfully pointed out that we are using the incorrect error code in some cases. This patch fixes that, and also removes the (unused) return value for glock dumping. > * gfs2_iget() - ENOBUFS instead of ENOMEM. ENOBUFS is > "No buffer space available (POSIX.1 (XSI STREAMS option))" and since > we don't support STREAMS it's probably fair game, but... what the hell? Signed-off-by: Steven Whitehouse Cc: Al Viro