summaryrefslogtreecommitdiff
path: root/fs/xfs/scrub/trace.h
AgeCommit message (Collapse)AuthorFilesLines
2024-02-22xfs: cache a bunch of inodes for repair scansDarrick J. Wong1-0/+23
After observing xfs_scrub taking forever to rebuild parent pointers on a pptrs enabled filesystem, I decided to profile what the system was doing. It turns out that when there are a lot of threads trying to scan the filesystem, most of our time is spent contending on AGI buffer locks. Given that we're walking the inobt records anyway, we can often tell ahead of time when there's a bunch of (up to 64) consecutive inodes that we could grab all at once. Do this to amortize the cost of taking the AGI lock across as many inodes as we possibly can. On the author's system this seems to improve parallel throughput from barely one and a half cores to slightly sublinear scaling. The obvious antipattern here of course is where the freemask has every other bit set (e.g. all 0xA's) Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-02-22xfs: stagger the starting AG of scrub iscans to reduce contentionDarrick J. Wong1-2/+5
Online directory and parent repairs on parent-pointer equipped filesystems have shown that starting a large number of parallel iscans causes a lot of AGI buffer contention. Try to reduce this by making it so that iscans scan wrap around the end of the filesystem, and using a rotor to stagger where each scanner begins. Surprisingly, this boosts CPU utilization (on the author's test machines) from effectively single-threaded to 160%. Not great, but see the next patch. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-02-22xfs: implement live inode scan for scrubDarrick J. Wong1-0/+106
This patch implements a live file scanner for online fsck functions that require the ability to walk a filesystem to gather metadata records and stay informed about metadata changes to files that have already been visited. The iscan structure consists of two inode number cursors: one to track which inode we want to visit next, and a second one to track which inodes have already been visited. This second cursor is key to capturing live updates to files previously scanned while the main thread continues scanning -- any inode greater than this value hasn't been scanned and can go on its way; any other update must be incorporated into the collected data. It is critical for the scanning thraad to hold exclusive access on the inode until after marking the inode visited. This new code is a separate patch from the patchsets adding callers for the sake of enabling the author to move patches around his tree with ease. The intended usage model for this code is roughly: xchk_iscan_start(iscan, 0, 0); while ((error = xchk_iscan_iter(sc, iscan, &ip)) == 1) { xfs_ilock(ip, ...); /* capture inode metadata */ xchk_iscan_mark_visited(iscan, ip); xfs_iunlock(ip, ...); xfs_irele(ip); } xchk_iscan_stop(iscan); if (error) return error; Hook functions for live updates can then do: if (xchk_iscan_want_live_update(...)) /* update the captured inode metadata */ Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2024-02-21xfs: remove xfile_{get,put}_pageDarrick J. Wong1-2/+0
These functions aren't used anymore, so get rid of them. Signed-off-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2024-02-21xfs: convert xfarray_pagesort to deal with large foliosDarrick J. Wong1-1/+42
Convert xfarray_pagesort to handle large folios by introducing a new xfile_get_folio routine that can return a folio of arbitrary size, and using heapsort on the full folio. This also corrects an off-by-one bug in the calculation of len in xfarray_pagesort that was papered over by xfarray_want_pagesort. Signed-off-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2024-02-21xfs: add file_{get,put}_folioDarrick J. Wong1-0/+2
Add helper similar to file_{get,set}_page, but which deal with folios and don't allocate new folio unless explicitly asked to, which map to shmem_get_folio instead of calling into the aops. Signed-off-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2024-02-21xfs: remove the xfile_pread/pwrite APIsChristoph Hellwig1-2/+2
All current and pending xfile users use the xfile_obj_load and xfile_obj_store API, so make those the actual implementation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2024-02-21xfs: remove xfile_statChristoph Hellwig1-24/+10
vfs_getattr is needed to query inode attributes for unknown underlying file systems. But shmemfs is well known for users of shmem_file_setup and shmem_read_mapping_page_gfp that rely on it not needing specific inode revalidation and having a normal mapping. Remove the detour through the getattr method and an extra wrapper, and just read the inode size and i_bytes directly in the scrub tracing code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2023-12-15xfs: repair quotasDarrick J. Wong1-0/+29
Fix anything that causes the quota verifiers to fail. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-15xfs: improve dquot iteration for scrubDarrick J. Wong1-0/+49
Upon a closer inspection of the quota record scrubber, I noticed that dqiterate wasn't actually walking all possible dquots for the mapped blocks in the quota file. This is due to xfs_qm_dqget_next skipping all XFS_IS_DQUOT_UNINITIALIZED dquots. For a fsck program, we really want to look at all the dquots, even if all counters and limits in the dquot record are zero. Rewrite the implementation to do this, as well as switching to an iterator paradigm to reduce the number of indirect calls. This enables removal of the old broken dqiterate code from xfs_dquot.c. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-15xfs: repair problems in CoW forksDarrick J. Wong1-0/+84
Try to repair errors that we see in file CoW forks so that we don't do stupid things like remap garbage into a file. There's not a lot we can do with the COW fork -- the ondisk metadata record only that the COW staging extents are owned by the refcount btree, which effectively means that we can't reconstruct this incore structure from scratch. Actually, this is even worse -- we can't touch written extents, because those map space that are actively under writeback, and there's not much to do with delalloc reservations. Hence we can only detect crosslinked unwritten extents and fix them by punching out the problematic parts and replacing them with delalloc extents. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-15xfs: repair inode fork block mapping data structuresDarrick J. Wong1-1/+33
Use the reverse-mapping btree information to rebuild an inode block map. Update the btree bulk loading code as necessary to support inode rooted btrees and fix some bitrot problems. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-15xfs: zap broken inode forksDarrick J. Wong1-0/+42
Determine if inode fork damage is responsible for the inode being unable to pass the ifork verifiers in xfs_iget and zap the fork contents if this is true. Once this is done the fork will be empty but we'll be able to construct an in-core inode, and a subsequent call to the inode fork repair ioctl will search the rmapbt to rebuild the records that were in the fork. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-15xfs: repair inode recordsDarrick J. Wong1-0/+129
If an inode is so badly damaged that it cannot be loaded into the cache, fix the ondisk metadata and try again. If there /is/ a cached inode, fix any problems and apply any optimizations that can be solved incore. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-15xfs: repair refcount btreesDarrick J. Wong1-10/+12
Reconstruct the refcount data from the rmap btree. Link: https://docs.kernel.org/filesystems/xfs-online-fsck-design.html#case-study-rebuilding-the-space-reference-counts Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-15xfs: repair inode btreesDarrick J. Wong1-34/+34
Use the rmapbt to find inode chunks, query the chunks to compute hole and free masks, and with that information rebuild the inobt and finobt. Refer to the case study in Documentation/filesystems/xfs-online-fsck-design.rst for more details. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-15xfs: repair free space btreesDarrick J. Wong1-1/+23
Rebuild the free space btrees from the gaps in the rmap btree. Refer to the case study in Documentation/filesystems/xfs-online-fsck-design.rst for more details. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-12-06xfs: implement block reservation accounting for btrees we're stagingDarrick J. Wong1-0/+37
Create a new xrep_newbt structure to encapsulate a fake root for creating a staged btree cursor as well as to track all the blocks that we need to reserve in order to build that btree. As for the particular choice of lowspace thresholds and btree block slack factors -- at this point one could say that the thresholds in online repair come from bulkload_estimate_ag_slack in xfs_repair[1]. But that's not the entire story, since the offline btree rebuilding code in xfs_repair was merged as a retroport of the online btree code in this patchset! Before xfs_btree_staging.[ch] came along, xfs_repair determined the slack factor (aka the number of slots to leave unfilled in each new btree block) via open-coded logic in repair/phase5.c[2]. At that point the slack factors were arbitrary quantities per btree. The rmapbt automatically left 10 slots free; everything else left zero. That had a noticeable effect on performance straight after mounting because adding records to /any/ btree would result in splits. A few years ago when this patch was first written, Dave and I decided that repair should generate btree blocks that were 75% full unless space was tight, in which case it should try to fill the blocks to nearly full. We defined tight as ~10% free to avoid repair failures but settled on 3/32 (~9%) to avoid div64. IOWs, we mostly pulled the thresholds out of thin air. We've been QAing with those geometry numbers ever since. ;) Link: https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git/tree/repair/bulkload.c?h=v6.5.0#n114 Link: https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git/tree/repair/phase5.c?h=v4.19.0#n1349 Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-10-18xfs: use accessor functions for summary info wordsDarrick J. Wong1-5/+5
Create get and set functions for rtsummary words so that we can redefine the ondisk format with a specific endianness. Note that this requires the definition of a distinct type for ondisk summary info words so that the compiler can perform proper typechecking. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17xfs: convert rt extent numbers to xfs_rtxnum_tDarrick J. Wong1-2/+2
Further disambiguate the xfs_rtblock_t uses by creating a new type, xfs_rtxnum_t, to store the position of an extent within the realtime section, in units of rtextents. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-10-17xfs: convert rt bitmap extent lengths to xfs_rtbxlen_tDarrick J. Wong1-1/+2
XFS uses xfs_rtblock_t for many different uses, which makes it much more difficult to perform a unit analysis on the codebase. One of these (ab)uses is when we need to store the length of a free space extent as stored in the realtime bitmap. Because there can be up to 2^64 realtime extents in a filesystem, we need a new type that is larger than xfs_rtxlen_t for callers that are querying the bitmap directly. This means scrub and growfs. Create this type as "xfs_rtbxlen_t" and use it to store 64-bit rtx lengths. 'b' stands for 'bitmap' or 'big'; reader's choice. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2023-08-30Merge tag 'xfs-6.6-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds1-32/+359
Pull xfs updates from Chandan Babu: - Chandan Babu will be taking over as the XFS release manager. He has reviewed all the patches that are in this branch, though I'm signing the branch one last time since I'm still technically maintainer. :P - Create a maintainer entry profile for XFS in which we lay out the various roles that I have played for many years. Aside from release manager, the remaining roles are as yet unfilled. - Start merging online repair -- we now have in-memory pageable memory for staging btrees, a bunch of pending fixes, and we've started the process of refactoring the scrub support code to support more of repair. In particular, reaping of old blocks from damaged structures. - Scrub the realtime summary file. - Fix a bug where scrub's quota iteration only ever returned the root dquot. Oooops. - Fix some typos. [ Pull request from Chandan Babu, but signed tag and description from Darrick Wong, thus the first person singular above is Darrick, not Chandan ] * tag 'xfs-6.6-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (37 commits) fs/xfs: Fix typos in comments xfs: fix dqiterate thinko xfs: don't check reflink iflag state when checking cow fork xfs: simplify returns in xchk_bmap xfs: rewrite xchk_inode_is_allocated to work properly xfs: hide xfs_inode_is_allocated in scrub common code xfs: fix agf_fllast when repairing an empty AGFL xfs: allow userspace to rebuild metadata structures xfs: clear pagf_agflreset when repairing the AGFL xfs: allow the user to cancel repairs before we start writing xfs: don't complain about unfixed metadata when repairs were injected xfs: implement online scrubbing of rtsummary info xfs: always rescan allegedly healthy per-ag metadata after repair xfs: move the realtime summary file scrubber to a separate source file xfs: wrap ilock/iunlock operations on sc->ip xfs: get our own reference to inodes that we want to scrub xfs: track usage statistics of online fsck xfs: improve xfarray quicksort pivot xfs: create scaffolding for creating debugfs entries xfs: cache pages used for xfarray quicksort convergence ...
2023-08-10xfs: rewrite xchk_inode_is_allocated to work properlyDarrick J. Wong1-0/+22
Back in the mists of time[1], I proposed this function to assist the inode btree scrubbers in checking the inode btree contents against the allocation state of the inode records. The original version performed a direct lookup in the inode cache and returned the allocation status if the cached inode hadn't been reused and wasn't in an intermediate state. Brian thought it would be better to use the usual iget/irele mechanisms, so that was changed for the final version. Unfortunately, this hasn't aged well -- the IGET_INCORE flag only has one user and clutters up the regular iget path, which makes it hard to reason about how it actually works. Worse yet, the inode inactivation series silently broke it because iget won't return inodes that are anywhere in the inactivation machinery, even though the caller is already required to prevent inode allocation and freeing. Inodes in the inactivation machinery are still allocated, but the current code's interactions with the iget code prevent us from being able to say that. Now that I understand the inode lifecycle better than I did in early 2017, I now realize that as long as the cached inode hasn't been reused and isn't actively being reclaimed, it's safe to access the i_mode field (with the AGI, rcu, and i_flags locks held), and we don't need to worry about the inode being freed out from under us. Therefore, port the original version to modern code structure, which fixes the brokennes w.r.t. inactivation. In the next patch we'll remove IGET_INCORE since it's no longer necessary. [1] https://lore.kernel.org/linux-xfs/149643868294.23065.8094890990886436794.stgit@birch.djwong.org/ Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: allow userspace to rebuild metadata structuresDarrick J. Wong1-1/+2
Add a new (superuser-only) flag to the online metadata repair ioctl to force it to rebuild structures, even if they're not broken. We will use this to move metadata structures out of the way during a free space defragmentation operation. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: implement online scrubbing of rtsummary infoDarrick J. Wong1-0/+34
Finish the realtime summary scrubber by adding the functions we need to compute a fresh copy of the rtsummary info and comparing it to the copy on disk. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: speed up xfarray sort by sorting xfile page contents directlyDarrick J. Wong1-0/+20
If all the records in an xfarray subset live within the same memory page, we can short-circuit even more quicksort recursion by mapping that page into the local CPU and using the kernel's heapsort function to sort the subset. On the author's computer, this reduces the runtime by another 15% on a 500,000 element array. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: teach xfile to pass back direct-map pages to callerDarrick J. Wong1-0/+2
Certain xfile array operations (such as sorting) can be sped up quite a bit by allowing xfile users to grab a page to bulk-read the records contained within it. Create helper methods to facilitate this. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: convert xfarray insertion sort to heapsort using scratchpad memoryDarrick J. Wong1-1/+4
In the previous patch, we created a very basic quicksort implementation for xfile arrays. While the use of an alternate sorting algorithm to avoid quicksort recursion on very small subsets reduces the runtime modestly, we could do better than a load and store-heavy insertion sort, particularly since each load and store requires a page mapping lookup in the xfile. For a small increase in kernel memory requirements, we could instead bulk load the xfarray records into memory, use the kernel's existing heapsort implementation to sort the records, and bulk store the memory buffer back into the xfile. On the author's computer, this reduces the runtime by about 5% on a 500,000 element array. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: enable sorting of xfile-backed arraysDarrick J. Wong1-0/+114
The btree bulk loading code requires that records be provided in the correct record sort order for the given btree type. In general, repair code cannot be required to collect records in order, and it is not feasible to insert new records in the middle of an array to maintain sort order. Implement a sorting algorithm so that we can sort the records just prior to bulk loading. In principle, an xfarray could consume many gigabytes of memory and its backing pages can be sent out to disk at any time. This means that we cannot map the entire array into memory at once, so we must find a way to divide the work into smaller portions (e.g. a page) that /can/ be mapped into memory. Quicksort seems like a reasonable fit for this purpose, since it uses a divide and conquer strategy to keep its average runtime logarithmic. The solution presented here is a port of the glibc implementation, which itself is derived from the median-of-three and tail call recursion strategies outlined by Sedgwick. Subsequent patches will optimize the implementation further by utilizing the kernel's heapsort on directly-mapped memory whenever possible, and improving the quicksort pivot selection algorithm to try to avoid O(n^2) collapses. Note: The sorting functionality gets its own patch because the basic big array mechanisms were plenty for a single code patch. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: create a big array data structureDarrick J. Wong1-0/+121
Create a simple 'big array' data structure for storage of fixed-size metadata records that will be used to reconstruct a btree index. For repair operations, the most important operations are append, iterate, and sort. Earlier implementations of the big array used linked lists and suffered from severe problems -- pinning all records in kernel memory was not a good idea and frequently lead to OOM situations; random access was very inefficient; and record overhead for the lists was unacceptably high at 40-60%. Therefore, the big memory array relies on the 'xfile' abstraction, which creates a memfd file and stores the records in page cache pages. Since the memfd is created in tmpfs, the memory pages can be pushed out to disk if necessary and we have a built-in usage limit of 50% of physical memory. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: reap large AG metadata extents when possibleDarrick J. Wong1-2/+35
When we're freeing extents that have been set in a bitmap, break the bitmap extent into multiple sub-extents organized by fate, and reap the extents. This enables us to dispose of old resources more efficiently than doing them block by block. While we're at it, rename the reaping functions to make it clear that they're reaping per-AG extents. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: rearrange xrep_reap_block to make future code flow easierDarrick J. Wong1-9/+8
Rearrange the logic inside xrep_reap_block to make it more obvious that crosslinked metadata blocks are handled differently. Add a couple of tracepoints so that we can tell what's going on at the end of a btree rebuild operation. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10xfs: cull repair code that will never get usedDarrick J. Wong1-22/+0
These two functions date from the era when I thought that we could rebuild btrees by creating an alternate root and adding records one by one. In other words, they predate the btree bulk loader. They're not necessary now, so remove them. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-04xfs: stabilize fs summary counters for online fsckDarrick J. Wong1-0/+26
If the fscounters scrubber notices incorrect summary counters, it's entirely possible that scrub is simply racing with other threads that are updating the incore counters. There isn't a good way to stabilize percpu counters or set ourselves up to observe live updates with hooks like we do for the quotacheck or nlinks scanners, so we instead choose to freeze the filesystem long enough to walk the incore per-AG structures. Past me thought that it was going to be commonplace to have to freeze the filesystem to perform some kind of repair and set up a whole separate infrastructure to freeze the filesystem in such a way that userspace could not unfreeze while we were running. This involved adding a mutex and freeze_super/thaw_super functions and dealing with the fact that the VFS freeze/thaw functions can free the VFS superblock references on return. This was all very overwrought, since fscounters turned out to be the only user of scrub freezes, and it doesn't require the log to quiesce, only the incore superblock counters. We prevent other threads from changing the freeze level by calling freeze_super_excl with a custom freeze cookie to keep everyone else out of the filesystem. The end result is that fscounters should be much more efficient. When we're checking a busy system and we can't stabilize the counters, the custom freeze will do less work, which should result in less downtime. Repair should be similarly speedy, but that's in a later patch. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-05-02xfs: disable reaping in fscounters scrubDarrick J. Wong1-1/+0
The fscounters scrub code doesn't work properly because it cannot quiesce updates to the percpu counters in the filesystem, hence it returns false corruption reports. This has been fixed properly in one of the online repair patchsets that are under review by replacing the xchk_disable_reaping calls with an exclusive filesystem freeze. Disabling background gc isn't sufficient to fix the problem. In other words, scrub doesn't need to call xfs_inodegc_stop, which is just as well since it wasn't correct to allow scrub to call xfs_inodegc_start when something else could be calling xfs_inodegc_stop (e.g. trying to freeze the filesystem). Neuter the scrubber for now, and remove the xchk_*_reaping functions. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2023-04-11xfs: scrub should use ECHRNG to signal that the drain is neededDarrick J. Wong1-0/+1
In the previous patch, we added jump labels to the intent drain code so that regular filesystem operations need not pay the price of checking for someone (scrub) waiting on intents to drain from some part of the filesystem when that someone isn't running. However, I observed that xfs/285 now spends a lot more time pushing the AIL from the inode btree scrubber than it used to. This is because the inobt scrubber will try push the AIL to try to get logged inode cores written to the filesystem when it sees a weird discrepancy between the ondisk inode and the inobt records. This AIL push is triggered when the setup function sees TRY_HARDER is set; and the requisite EDEADLOCK return is initiated when the discrepancy is seen. The solution to this performance slow down is to use a different result code (ECHRNG) for scrub code to signal that it needs to wait for deferred intent work items to drain out of some part of the filesystem. When this happens, set a new scrub state flag (XCHK_NEED_DRAIN) so that setup functions will activate the jump label. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-04-11xfs: minimize overhead of drain wakeups by using jump labelsDarrick J. Wong1-0/+33
To reduce the runtime overhead even further when online fsck isn't running, use a static branch key to decide if we call wake_up on the drain. For compilers that support jump labels, the call to wake_up is replaced by a nop sled when nobody is waiting for intents to drain. From my initial microbenchmarking, every transition of the static key between the on and off states takes about 22000ns to complete; this is paid entirely by the xfs_scrub process. When the static key is off (which it should be when fsck isn't running), the nop sled adds an overhead of approximately 0.36ns to runtime code. The post-atomic lockless waiter check adds about 0.03ns, which is basically free. For the few compilers that don't support jump labels, runtime code pays the cost of calling wake_up on an empty waitqueue, which was observed to be about 30ns. However, most architectures that have sufficient memory and CPU capacity to run XFS also support jump labels, so this is not much of a worry. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-04-11xfs: add a tracepoint to report incorrect extent refcountsDarrick J. Wong1-0/+35
Add a new tracepoint so that I can see exactly what and where we failed the refcount check. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-04-11xfs: update copyright years for scrub/ filesDarrick J. Wong1-1/+1
Update the copyright years in the scrub/ source code files. This isn't required, but it's helpful to remind myself just how long it's taken to develop this feature. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-04-11xfs: fix author and spdx headers on scrub/ filesDarrick J. Wong1-2/+2
Fix the spdx tags to match current practice, and update the author contact information. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2021-10-19xfs: prepare xfs_btree_cur for dynamic cursor heightsDarrick J. Wong1-5/+5
Split out the btree level information into a separate struct and put it at the end of the cursor structure as a VLA. Files with huge data forks (and in the future, the realtime rmap btree) will require the ability to support many more levels than a per-AG btree cursor, which means that we're going to create per-btree type cursor caches to conserve memory for the more common case. Note that a subsequent patch actually introduces dynamic cursor heights. This one merely rearranges the structure to prepare for that. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Chandan Babu R <chandan.babu@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com>
2021-08-19xfs: start documenting common units and tags used in tracepointsDarrick J. Wong1-0/+4
Because there are a lot of tracepoints that express numeric data with an associated unit and tag, document what they are to help everyone else keep these thigns straight. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-08-19xfs: decode scrub flags in ftrace outputDarrick J. Wong1-2/+12
When using pretty-printed scrub tracepoints, decode the meaning of the scrub flags as strings for easier reading. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-08-19xfs: standardize inode generation formatting in ftrace outputDarrick J. Wong1-1/+1
Always print inode generation in hexadecimal and preceded with the unit "gen". Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-08-19xfs: resolve fork names in trace outputDarrick J. Wong1-8/+8
Emit whichfork values as text strings in the ftrace output. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-08-19xfs: disambiguate units for ftrace fields tagged "len"Darrick J. Wong1-4/+4
Some of our tracepoints have a field known as "len". That name doesn't describe any units, which makes the fields not very useful. Rename the fields to capture units and ensure the format is hexadecimal. "fsbcount" are in units of fs blocks "bbcount" are in units of 512b blocks "ireccount" are in units of inodes Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-08-19xfs: disambiguate units for ftrace fields tagged "offset"Darrick J. Wong1-3/+3
Some of our tracepoints describe fields as "offset". That name doesn't describe any units, which makes the fields not very useful. Rename the fields to capture units and ensure the format is hexadecimal. "fileoff" means file offset, in units of fs blocks "pos" means file offset, in bytes "forkoff" means inode fork offset, in bytes The one remaining "offset" value is for iclogs, since that's the byte offset of the end of where we've written into the current iclog. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-08-19xfs: standardize rmap owner number formatting in ftrace outputDarrick J. Wong1-1/+1
Always print rmap owner number in hexadecimal and preceded with the unit "owner". Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-08-19xfs: standardize AG block number formatting in ftrace outputDarrick J. Wong1-12/+12
Always print allocation group block numbers in hexadecimal and preceded with the unit "agbno". Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2021-08-19xfs: standardize AG number formatting in ftrace outputDarrick J. Wong1-17/+17
Always print allocation group numbers in hexadecimal and preceded with the unit "agno". Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>