- 24 Mar, 2018 6 commits
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Darrick J. Wong authored
Refactor some of the inode verifier failure logging call sites to use the new xfs_inode_verifier_error method which dumps the offending buffer as well as the code location of the failed check. This trims the output, makes it clearer to the admin that repair must be run, and gives the developers more details to work from. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
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Darrick J. Wong authored
Refactor the bmap validator into a more complete helper that looks for extents that run off the end of the device, overflow into the next AG, or have invalid flag states. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
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Darrick J. Wong authored
In xfs_dir2_data_use_free, we examine on-disk metadata and ASSERT if it doesn't make sense. Since a carefully crafted fuzzed image can cause the kernel to crash after blowing a bunch of assertions, let's move those checks into a validator function and rig everything up to return EFSCORRUPTED to userspace. Found by lastbit fuzzing ltail.bestcount via xfs/391. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
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Brian Foster authored
The struct xfs_agfl v5 header was originally introduced with unexpected padding that caused the AGFL to operate with one less slot than intended. The header has since been packed, but the fix left an incompatibility for users who upgrade from an old kernel with the unpacked header to a newer kernel with the packed header while the AGFL happens to wrap around the end. The newer kernel recognizes one extra slot at the physical end of the AGFL that the previous kernel did not. The new kernel will eventually attempt to allocate a block from that slot, which contains invalid data, and cause a crash. This condition can be detected by comparing the active range of the AGFL to the count. While this detects a padding mismatch, it can also trigger false positives for unrelated flcount corruption. Since we cannot distinguish a size mismatch due to padding from unrelated corruption, we can't trust the AGFL enough to simply repopulate the empty slot. Instead, avoid unnecessarily complex detection logic and and use a solution that can handle any form of flcount corruption that slips through read verifiers: distrust the entire AGFL and reset it to an empty state. Any valid blocks within the AGFL are intentionally leaked. This requires xfs_repair to rectify (which was already necessary based on the state the AGFL was found in). The reset mitigates the side effect of the padding mismatch problem from a filesystem crash to a free space accounting inconsistency. The generic approach also means that this patch can be safely backported to kernels with or without a packed struct xfs_agfl. Check the AGF for an invalid freelist count on initial read from disk. If detected, set a flag on the xfs_perag to indicate that a reset is required before the AGFL can be used. In the first transaction that attempts to use a flagged AGFL, reset it to empty, warn the user about the inconsistency and allow the freelist fixup code to repopulate the AGFL with new blocks. The xfs_perag flag is cleared to eliminate the need for repeated checks on each block allocation operation. This allows kernels that include the packing fix commit 96f859d5 ("libxfs: pack the agfl header structure so XFS_AGFL_SIZE is correct") to handle older unpacked AGFL formats without a filesystem crash. Suggested-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by Dave Chiluk <chiluk+linuxxfs@indeed.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Instead split out a __xfs_log_fore_lsn helper that gets called again with the already_slept flag set to true in case we had to sleep. This prepares for aio_fsync support. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Use the the smallest possible loop as preable to find the correct iclog buffer, and then use gotos for unwinding to straighten the code. Also fix the top of function comment while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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- 15 Mar, 2018 6 commits
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Christoph Hellwig authored
Use xfs_iext_prev_extent to skip to the previous extent instead of opencoding it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Simplify the control flow a bit in preparation for O_ATOMIC-related changes. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
This helper doesn't add any real value over just calling iomap_zero_range directly, so remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Now that we convert COW preallocations from unwritten to real on every call this function needs to be called with the ilock held exclusively. Fortunately we already do that, but update the assert to match. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
There is no reason to get a mapping bigger than what we were asked for. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
i_cnextents does not include delayed allocated extents, so switch to the inode fork size check that we already use in other places instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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- 14 Mar, 2018 6 commits
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Christoph Hellwig authored
Streamline the conditionals so that it is more obvious which specific case form the top of the function comments is being handled. Use gotos only for early returns. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Switch to a single interface for flushing the log to a specific LSN, which gives consistent trace point coverage and a less confusing interface. The was only a single user of the previous xfs_log_force_lsn function, which now also passes a NULL log_flushed argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Switch to a single interface for flushing the whole log, which gives consistent trace point coverage, and removes the unused log_flushed argument for the previous _xfs_log_force callers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
The function now does something, and that something is central to our inode logging scheme. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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- 12 Mar, 2018 19 commits
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Brian Foster authored
The rmapbt perag metadata reservation reserves blocks for the reverse mapping btree (rmapbt). Since the rmapbt uses blocks from the agfl and perag accounting is updated as blocks are allocated from the allocation btrees, the reservation actually accounts blocks as they are allocated to (or freed from) the agfl rather than the rmapbt itself. While this works for blocks that are eventually used for the rmapbt, not all agfl blocks are destined for the rmapbt. Blocks that are allocated to the agfl (and thus "reserved" for the rmapbt) but then used by another structure leads to a growing inconsistency over time between the runtime tracking of rmapbt usage vs. actual rmapbt usage. Since the runtime tracking thinks all agfl blocks are rmapbt blocks, it essentially believes that less future reservation is required to satisfy the rmapbt than what is actually necessary. The inconsistency is rectified across mount cycles because the perag reservation is initialized based on the actual rmapbt usage at mount time. The problem, however, is that the excessive drain of the reservation at runtime opens a window to allocate blocks for other purposes that might be required for the rmapbt on a subsequent mount. This problem can be demonstrated by a simple test that runs an allocation workload to consume agfl blocks over time and then observe the difference in the agfl reservation requirement across an unmount/mount cycle: mount ...: xfs_ag_resv_init: ... resv 3193 ask 3194 len 3194 ... ... : xfs_ag_resv_alloc_extent: ... resv 2957 ask 3194 len 1 umount...: xfs_ag_resv_free: ... resv 2956 ask 3194 len 0 mount ...: xfs_ag_resv_init: ... resv 3052 ask 3194 len 3194 As the above tracepoints show, the reservation requirement reduces from 3194 blocks to 2956 blocks as the workload runs. Without any other changes in the filesystem, the same reservation requirement jumps from 2956 to 3052 blocks over a umount/mount cycle. To address this divergence, update the RMAPBT reservation to account blocks used for the rmapbt only rather than all blocks filled into the agfl. This patch makes several high-level changes toward that end: 1.) Reintroduce an AGFL reservation type to serve as an accounting no-op for blocks allocated to (or freed from) the AGFL. 2.) Invoke RMAPBT usage accounting from the actual rmapbt block allocation path rather than the AGFL allocation path. The first change is required because agfl blocks are considered free blocks throughout their lifetime. The perag reservation subsystem is invoked unconditionally by the allocation subsystem, so we need a way to tell the perag subsystem (via the allocation subsystem) to not make any accounting changes for blocks filled into the AGFL. The second change causes the in-core RMAPBT reservation usage accounting to remain consistent with the on-disk state at all times and eliminates the risk of leaving the rmapbt reservation underfilled. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Brian Foster authored
The AGFL perag reservation type accounts all allocations that feed into (or are released from) the allocation group free list (agfl). The purpose of the reservation is to support worst case conditions for the reverse mapping btree (rmapbt). As such, the agfl reservation usage accounting only considers rmapbt usage when the in-core counters are initialized at mount time. This implementation inconsistency leads to divergence of the in-core and on-disk usage accounting over time. In preparation to resolve this inconsistency and adjust the AGFL reservation into an rmapbt specific reservation, rename the AGFL reservation type and associated accounting fields to something more rmapbt-specific. Also fix up a couple tracepoints that incorrectly use the AGFL reservation type to pass the agfl state of the associated extent where the raw reservation type is expected. Note that this patch does not change perag reservation behavior. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Brian Foster authored
The extent swap mechanism requires a unique implementation for rmapbt enabled filesystems. Because the rmapbt tracks extent owner information, extent swap must individually unmap and remap each extent between the two inodes. The rmapbt extent swap transaction block reservation currently accounts for the worst case bmapbt block and rmapbt block consumption based on the extent count of each inode. There is a corner case that exists due to the extent swap implementation that is not covered by this reservation, however. If one of the associated inodes is just over the max extent count used for extent format inodes (i.e., the inode is in btree format by a single extent), the unmap/remap cycle of the extent swap can bounce the inode between extent and btree format multiple times, almost as many times as there are extents in the inode (if the opposing inode happens to have one less, for example). Each back and forth cycle involves a block free and allocation, which isn't a problem except for that the initial transaction reservation must account for the total number of block allocations performed by the chain of deferred operations. If not, a block reservation overrun occurs and the filesystem shuts down. Update the rmapbt extent swap block reservation to check for this situation and add some block reservation slop to ensure the entire operation succeeds. We'd never likely require reservation for both inodes as fsr wouldn't defrag the file in that case, but the additional reservation is constrained by the data fork size so be cautious and check for both. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Brian Foster authored
The ->t_blk_res_used field tracks how many blocks have been used in the current transaction. This should never exceed the block reservation (->t_blk_res) for a particular transaction. We currently assert this condition in the transaction block accounting code, but otherwise take no additional action should this situation occur. The overrun generally has no effect if space ends up being available and the associated transaction commits. If the transaction is duplicated, however, the current block usage is used to determine the remaining block reservation to be transferred to the new transaction. If usage exceeds reservation, this calculation underflows and creates a transaction with an invalid and excessive reservation. When the second transaction commits, the release of unused blocks corrupts the in-core free space counters. With lazy superblock accounting enabled, this inconsistency eventually trickles to the on-disk superblock and corrupts the filesystem. Replace the transaction block usage accounting assert with an explicit overrun check. If the transaction overruns the reservation, shutdown the filesystem immediately to prevent corruption. Add a new assert to xfs_trans_dup() to catch any callers that might induce this invalid state in the future. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Matthew Wilcox authored
This is a simple rename, except that xa_ail becomes ail_head. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Dave Chinner authored
Noticed when looking at why cycling 600k inodes/s through the inode cache was taking a total of 8% cpu in memset() during inode initialisation. There is no need to zero the inode.i_data structure twice. This increases single threaded bulkstat throughput from ~200,000 inodes/s to ~220,000 inodes/s, so we save a substantial amount of CPU time per inode init by doing this. Signed-Off-By: Dave Chinner <dchinner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Dave Chinner authored
The AGFL size calculation is about to get more complex, so lets turn the macro into a function first and remove the macro. Signed-off-by: Dave Chinner <dchinner@redhat.com> [darrick: forward port to newer kernel, simplify the helper] Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
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Darrick J. Wong authored
There's no point in allocating a transaction and locking the inode in preparation to clear cow blocks if there actually are any cow fork extents. Therefore, move the xfs_reflink_cancel_cow_range hunk to xfs_inactive and check the cow ifp first. This makes inode reclamation run faster. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
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Darrick J. Wong authored
Yet another round of playing whack-a-mole with directory code that asserts on corrupt on-disk metadata when it really should be returning -EFSCORRUPTED instead of ASSERTing. Found by a xfs/391 crash while lastbit fuzzing of ltail.bestcount. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
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Darrick J. Wong authored
In xfs_qm_dqalloc, we join the locked quota inode to the transaction we use to allocate blocks. If the allocation or mapping fails, we're not allowed to unlock the inode because the transaction code is in charge of unlocking it for us. Therefore, remove the iunlock call to avoid blowing asserts about unbalanced locking + mount hang. Found by corrupting the AGF and allocating space in the filesystem (quotacheck) immediately after mount. The upcoming agfl wrapping fixup test will trigger this scenario. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
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Vratislav Bendel authored
Due to an inverted logic mistake in xfs_buftarg_isolate() the xfs_buffers with zero b_lru_ref will take another trip around LRU, while isolating buffers with non-zero b_lru_ref. Additionally those isolated buffers end up right back on the LRU once they are released, because b_lru_ref remains elevated. Fix that circuitous route by leaving them on the LRU as originally intended. Signed-off-by: Vratislav Bendel <vbendel@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Dave Chinner authored
xfs_trans_alloc() does GFP_KERNEL allocation, and we can call it while holding pages locked for writeback in the ->writepages path. The memory allocation is allowed to wait on pages under writeback, and so can wait on pages that are tagged as writeback by the caller. This affects both pre-IO submission and post-IO submission paths. Hence xfs_setsize_trans_alloc(), xfs_reflink_end_cow(), xfs_iomap_write_unwritten() and xfs_reflink_cancel_cow_range(). xfs_iomap_write_unwritten() already does the right thing, but the others don't. Fix them. Signed-Off-By: Dave Chinner <dchinner@redhat.com> Fixes: 281627df ("xfs: log file size updates at I/O completion time") Fixes: 43caeb18 ("xfs: move mappings from cow fork to data fork after copy-write)" Reviewed-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
Use the VFS dirty inode tracking for lazytime inodes only, and just log them in ->dirty_inode. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Christoph Hellwig authored
__mark_inode_dirty already takes care of that, and for the XFS lazytime implementation we need to know that ->dirty_inode was called because I_DIRTY_TIME was set. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Nikolay Borisov authored
The memcpy is guarded by a check which is performed a right before we call xfs_log_dinode_to_disk. At this point we are sure this check will always be false otherwise we would have errored out. So let's remove this dead weight. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Carlos Maiolino authored
Remove unused legacy btree traces from IRIX era. Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Eric Sandeen authored
The dmevmask structure member is a dmapi leftover; it's set here and there but never actually used. Remove it. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Bill O'Donnell <billodo@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Dave Chinner authored
When using large directory blocks, we regularly see memory allocations of >64k being made for the shadow log vector buffer. When we are under memory pressure, kmalloc() may not be able to find contiguous memory chunks large enough to satisfy these allocations easily, and if memory is fragmented we can potentially stall here. TO avoid this problem, switch the log vector buffer allocation to use kmem_alloc_large(). This will allow failed allocations to fall back to vmalloc and so remove the dependency on large contiguous regions of memory being available. This should prevent slowdowns and potential stalls when memory is low and/or fragmented. Signed-Off-By: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
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Linus Torvalds authored
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- 11 Mar, 2018 3 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86/pti updates from Thomas Gleixner: "Yet another pile of melted spectrum related updates: - Drop native vsyscall support finally as it causes more trouble than benefit. - Make microcode loading more robust. There were a few issues especially related to late loading which are now surfacing because late loading of the IB* microcodes addressing spectre issues has become more widely used. - Simplify and robustify the syscall handling in the entry code - Prevent kprobes on the entry trampoline code which lead to kernel crashes when the probe hits before CR3 is updated - Don't check microcode versions when running on hypervisors as they are considered as lying anyway. - Fix the 32bit objtool build and a coment typo" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/kprobes: Fix kernel crash when probing .entry_trampoline code x86/pti: Fix a comment typo x86/microcode: Synchronize late microcode loading x86/microcode: Request microcode on the BSP x86/microcode/intel: Look into the patch cache first x86/microcode: Do not upload microcode if CPUs are offline x86/microcode/intel: Writeback and invalidate caches before updating microcode x86/microcode/intel: Check microcode revision before updating sibling threads x86/microcode: Get rid of struct apply_microcode_ctx x86/spectre_v2: Don't check microcode versions when running under hypervisors x86/vsyscall/64: Drop "native" vsyscalls x86/entry/64/compat: Save one instruction in entry_INT80_compat() x86/entry: Do not special-case clone(2) in compat entry x86/syscalls: Use COMPAT_SYSCALL_DEFINEx() macros for x86-only compat syscalls x86/syscalls: Use proper syscall definition for sys_ioperm() x86/entry: Remove stale syscall prototype x86/syscalls/32: Simplify $entry == $compat entries objtool: Fix 32-bit build
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull timer fix from Thomas Gleixner: "Just a single fix which adds a missing Kconfig dependency to avoid unmet dependency warnings" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource/atmel-st: Add 'depends on HAS_IOMEM' to fix unmet dependency
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull RAS fixes from Thomas Gleixner: "Two small fixes for RAS/MCE: - Serialize sysfs changes to avoid concurrent modificaiton of underlying data - Add microcode revision to Machine Check records. This should have been there forever, but now with the broken microcode versions in the wild it has become important" * 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/MCE: Serialize sysfs changes x86/MCE: Save microcode revision in machine check records
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