kernel.git/fs/xfs/xfs_alloc.c, branch linux-3.14.y

xfs: add tracepoints to AGF/AGI read operations

2013-11-06T18:42:52Z

To help track down AGI/AGF lock ordering issues, I added these tracepoints to tell us when an AGI or AGF is read and locked. With these we can now determine if the lock ordering goes wrong from tracing captures. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig Signed-off-by: Ben Myers

xfs: decouple inode and bmap btree header files

2013-10-23T21:28:49Z

Currently the xfs_inode.h header has a dependency on the definition of the BMAP btree records as the inode fork includes an array of xfs_bmbt_rec_host_t objects in it's definition. Move all the btree format definitions from xfs_btree.h, xfs_bmap_btree.h, xfs_alloc_btree.h and xfs_ialloc_btree.h to xfs_format.h to continue the process of centralising the on-disk format definitions. With this done, the xfs inode definitions are no longer dependent on btree header files. The enables a massive culling of unnecessary includes, with close to 200 #include directives removed from the XFS kernel code base. Signed-off-by: Dave Chinner Reviewed-by: Ben Myers Signed-off-by: Ben Myers

xfs: decouple log and transaction headers

2013-10-23T21:17:44Z

xfs_trans.h has a dependency on xfs_log.h for a couple of structures. Most code that does transactions doesn't need to know anything about the log, but this dependency means that they have to include xfs_log.h. Decouple the xfs_trans.h and xfs_log.h header files and clean up the includes to be in dependency order. In doing this, remove the direct include of xfs_trans_reserve.h from xfs_trans.h so that we remove the dependency between xfs_trans.h and xfs_mount.h. Hence the xfs_trans.h include can be moved to the indicate the actual dependencies other header files have on it. Note that these are kernel only header files, so this does not translate to any userspace changes at all. Signed-off-by: Dave Chinner Reviewed-by: Ben Myers Signed-off-by: Ben Myers

xfs: create a shared header file for format-related information

2013-10-23T19:11:30Z

All of the buffer operations structures are needed to be exported for xfs_db, so move them all to a common location rather than spreading them all over the place. They are verifying the on-disk format, so while xfs_format.h might be a good place, it is not part of the on disk format. Hence we need to create a new header file that we centralise these related definitions. Start by moving the bffer operations structures, and then also move all the other definitions that have crept into xfs_log_format.h and xfs_format.h as there was no other shared header file to put them in. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig Signed-off-by: Ben Myers

xfs: kill KERNEL check for debug code in allocation code

2013-08-12T21:57:51Z

Userspace running debug builds is relatively rare, so there's need to special case the allocation algorithm code coverage debug switch. As it is, userspace defines random numbers to 0, so invert the logic of the switch so it is effectively a no-op in userspace. This kills another couple of __KERNEL__ users. Signed-off-by: Dave Chinner Reviewed-by: Mark Tinguely Signed-off-by: Ben Myers

xfs: Avoid pathological backwards allocation

2013-05-20T18:09:11Z

Writing a large file using direct IO in 16 MB chunks sometimes results in a pathological allocation pattern where 16 MB chunks of large free extent are allocated to a file in a reversed order. So extents of a file look for example as: ext logical physical expected length flags 0 0 13 4550656 1 4550656 188136807 4550668 12562432 2 17113088 200699240 200699238 622592 3 17735680 182046055 201321831 4096 4 17739776 182041959 182050150 4096 5 17743872 182037863 182046054 4096 6 17747968 182033767 182041958 4096 7 17752064 182029671 182037862 4096 ... 6757 45400064 154381644 154389835 4096 6758 45404160 154377548 154385739 4096 6759 45408256 252951571 154381643 73728 eof This happens because XFS_ALLOCTYPE_THIS_BNO allocation fails (the last extent in the file cannot be further extended) so we fall back to XFS_ALLOCTYPE_NEAR_BNO allocation which picks end of a large free extent as the best place to continue the file. Since the chunk at the end of the free extent again cannot be further extended, this behavior repeats until the whole free extent is consumed in a reversed order. For data allocations this backward allocation isn't beneficial so make xfs_alloc_compute_diff() pick start of a free extent instead of its end for them. That avoids the backward allocation pattern. See thread at http://oss.sgi.com/archives/xfs/2013-03/msg00144.html for more details about the reproduction case and why this solution was chosen. Based on idea by Dave Chinner . CC: Dave Chinner Signed-off-by: Jan Kara Reviewed-by: Dave Chinner Reviewed-by: Mark Tinguely Signed-off-by: Ben Myers

xfs: buffer type overruns blf_flags field

2013-04-27T18:01:58Z

The buffer type passed to log recvoery in the buffer log item overruns the blf_flags field. I had assumed that flags field was a 32 bit value, and it turns out it is a unisgned short. Therefore having 19 flags doesn't really work. Convert the buffer type field to numeric value, and use the top 5 bits of the flags field for it. We currently have 17 types of buffers, so using 5 bits gives us plenty of room for expansion in future.... Signed-off-by: Dave Chinner Reviewed-by: Ben Myers Signed-off-by: Ben Myers

xfs: add CRC checks to the AGFL

2013-04-21T19:55:34Z

Add CRC checks, location information and a magic number to the AGFL. Previously the AGFL was just a block containing nothing but the free block pointers. The new AGFL has a real header with the usual boilerplate instead, so that we can verify it's not corrupted and written into the right place. [dchinner@redhat.com] Added LSN field, reworked significantly to fit into new verifier structure and growfs structure, enabled full verifier functionality now there is a header to verify and we can guarantee an initialised AGFL. Signed-off-by: Christoph Hellwig Signed-off-by: Dave Chinner Reviewed-by: Ben Myers Signed-off-by: Ben Myers

xfs: add CRC checks to the AGF

2013-04-21T19:54:46Z

The AGF already has some self identifying fields (e.g. the sequence number) so we only need to add the uuid to it to identify the filesystem it belongs to. The location is fixed based on the sequence number, so there's no need to add a block number, either. Hence the only additional fields are the CRC and LSN fields. These are unlogged, so place some space between the end of the logged fields and them so that future expansion of the AGF for logged fields can be placed adjacent to the existing logged fields and hence not complicate the field-derived range based logging we currently have. Based originally on a patch from myself, modified further by Christoph Hellwig and then modified again to fit into the verifier structure with additional fields by myself. The multiple signed-off-by tags indicate the age and history of this patch. Signed-off-by: Dave Chinner Signed-off-by: Christoph Hellwig Signed-off-by: Dave Chinner Reviewed-by: Ben Myers Signed-off-by: Ben Myers

xfs: rename random32() to prandom_u32()

2013-03-07T18:33:57Z

Use more preferable function name which implies using a pseudo-random number generator. Signed-off-by: Akinobu Mita Acked-by: Cc: Ben Myers Cc: Alex Elder Cc: xfs@oss.sgi.com Signed-off-by: Ben Myers