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* module/*.ko: prune .data, global .rodataнаб2022-01-141-2/+2
| | | | | | | | | | | | Evaluated every variable that lives in .data (and globals in .rodata) in the kernel modules, and constified/eliminated/localised them appropriately. This means that all read-only data is now actually read-only data, and, if possible, at file scope. A lot of previously- global-symbols became inlinable (and inlined!) constants. Probably not in a big Wowee Performance Moment, but hey. Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Ahelenia Ziemiańska <[email protected]> Closes #12899
* Fix dRAID sequential resilver silent damage handlingBrian Behlendorf2021-05-201-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change addresses two distinct scenarios which are possible when performing a sequential resilver to a dRAID pool with vdevs that contain silent unknown damage. Which in this circumstance took the form of the devices being intentionally overwritten with zeros. However, it could also result from a device returning incorrect data while a sequential resilver was in progress. Scenario 1) A sequential resilver is performed while all of the dRAID vdevs are ONLINE and there is silent damage present on the vdev being resilvered. In this case, nothing will be repaired by vdev_raidz_io_done_reconstruct_known_missing() because rc->rc_error isn't set on any of the raid columns. To address this vdev_draid_io_start_read() has been updated to always mark the resilvering column as ESTALE for sequential resilver IO. Scenario 2) Multiple columns contain silent damage for the same block and a sequential resilver is performed. In this case it's impossible to generate the correct data from parity unless all of the damaged columns are being sequentially resilvered (and thus only good data is used to generate parity). This is as expected and there's nothing which can be done about it. However, we need to be careful not to make to situation worse. Since we can't verify the data is actually good without a checksum, we must only repair the devices which are being sequentially resilvered. Otherwise, an incorrect repair to a device which previously contained good data could effectively lock in the damage and make reconstruction impossible. A check for this was added to vdev_raidz_io_done_verified() along with a new test case. Lastly, this change updates the redundancy_draid_spare1 and redundancy_draid_spare3 test cases to be more representative of normal dRAID replacement operation. Specifically, what we care about is that the scrub run after a sequential resilver does not find additional blocks which need repair. This would indicate the sequential resilver failed to rebuild a section of one of the devices. Note also the tests were switched to using the verify_pool() function which still checks for checksum errors. Reviewed-by: Mark Maybee <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #12061
* Clean up RAIDZ/DRAID ereport codeMatthew Ahrens2021-03-191-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The RAIDZ and DRAID code is responsible for reporting checksum errors on their child vdevs. Checksum errors represent events where a disk returned data or parity that should have been correct, but was not. In other words, these are instances of silent data corruption. The checksum errors show up in the vdev stats (and thus `zpool status`'s CKSUM column), and in the event log (`zpool events`). Note, this is in contrast with the more common "noisy" errors where a disk goes offline, in which case ZFS knows that the disk is bad and doesn't try to read it, or the device returns an error on the requested read or write operation. RAIDZ/DRAID generate checksum errors via three code paths: 1. When RAIDZ/DRAID reconstructs a damaged block, checksum errors are reported on any children whose data was not used during the reconstruction. This is handled in `raidz_reconstruct()`. This is the most common type of RAIDZ/DRAID checksum error. 2. When RAIDZ/DRAID is not able to reconstruct a damaged block, that means that the data has been lost. The zio fails and an error is returned to the consumer (e.g. the read(2) system call). This would happen if, for example, three different disks in a RAIDZ2 group are silently damaged. Since the damage is silent, it isn't possible to know which three disks are damaged, so a checksum error is reported against every child that returned data or parity for this read. (For DRAID, typically only one "group" of children is involved in each io.) This case is handled in `vdev_raidz_cksum_finish()`. This is the next most common type of RAIDZ/DRAID checksum error. 3. If RAIDZ/DRAID is not able to reconstruct a damaged block (like in case 2), but there happens to be additional copies of this block due to "ditto blocks" (i.e. multiple DVA's in this blkptr_t), and one of those copies is good, then RAIDZ/DRAID compares each sector of the data or parity that it retrieved with the good data from the other DVA, and if they differ then it reports a checksum error on this child. This differs from case 2 in that the checksum error is reported on only the subset of children that actually have bad data or parity. This case happens very rarely, since normally only metadata has ditto blocks. If the silent damage is extensive, there will be many instances of case 2, and the pool will likely be unrecoverable. The code for handling case 3 is considerably more complicated than the other cases, for two reasons: 1. It needs to run after the main raidz read logic has completed. The data RAIDZ read needs to be preserved until after the alternate DVA has been read, which necessitates refcounts and callbacks managed by the non-raidz-specific zio layer. 2. It's nontrivial to map the sections of data read by RAIDZ to the correct data. For example, the correct data does not include the parity information, so the parity must be recalculated based on the correct data, and then compared to the parity that was read from the RAIDZ children. Due to the complexity of case 3, the rareness of hitting it, and the minimal benefit it provides above case 2, this commit removes the code for case 3. These types of errors will now be handled the same as case 2, i.e. the checksum error will be reported against all children that returned data or parity. Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Matthew Ahrens <[email protected]> Closes #11735
* Remove unused rr_codeMatthew Ahrens2021-03-171-1/+0
| | | | | | | | | | The `rr_code` field in `raidz_row_t` is unused. This commit removes the field, as well as the code that's used to set it. Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Matthew Ahrens <[email protected]> Closes #11736
* allow callers to allocate and provide the abd_t structMatthew Ahrens2021-01-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | The `abd_get_offset_*()` routines create an abd_t that references another abd_t, and doesn't allocate any pages/buffers of its own. In some workloads, these routines may be called frequently, to create many abd_t's representing small pieces of a single large abd_t. In particular, the upcoming RAIDZ Expansion project makes heavy use of these routines. This commit adds the ability for the caller to allocate and provide the abd_t struct to a variant of `abd_get_offset_*()`. This eliminates the cost of allocating the abd_t and performing the accounting associated with it (`abdstat_struct_size`). The RAIDZ/DRAID code uses this for the `rc_abd`, which references the zio's abd. The upcoming RAIDZ Expansion project will leverage this infrastructure to increase performance of reads post-expansion by around 50%. Additionally, some of the interfaces around creating and destroying abd_t's are cleaned up. Most significantly, the distinction between `abd_put()` and `abd_free()` is eliminated; all types of abd_t's are now disposed of with `abd_free()`. Reviewed-by: Brian Atkinson <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Matthew Ahrens <[email protected]> Issue #8853 Closes #11439
* Distributed Spare (dRAID) FeatureBrian Behlendorf2020-11-131-22/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a new top-level vdev type called dRAID, which stands for Distributed parity RAID. This pool configuration allows all dRAID vdevs to participate when rebuilding to a distributed hot spare device. This can substantially reduce the total time required to restore full parity to pool with a failed device. A dRAID pool can be created using the new top-level `draid` type. Like `raidz`, the desired redundancy is specified after the type: `draid[1,2,3]`. No additional information is required to create the pool and reasonable default values will be chosen based on the number of child vdevs in the dRAID vdev. zpool create <pool> draid[1,2,3] <vdevs...> Unlike raidz, additional optional dRAID configuration values can be provided as part of the draid type as colon separated values. This allows administrators to fully specify a layout for either performance or capacity reasons. The supported options include: zpool create <pool> \ draid[<parity>][:<data>d][:<children>c][:<spares>s] \ <vdevs...> - draid[parity] - Parity level (default 1) - draid[:<data>d] - Data devices per group (default 8) - draid[:<children>c] - Expected number of child vdevs - draid[:<spares>s] - Distributed hot spares (default 0) Abbreviated example `zpool status` output for a 68 disk dRAID pool with two distributed spares using special allocation classes. ``` pool: tank state: ONLINE config: NAME STATE READ WRITE CKSUM slag7 ONLINE 0 0 0 draid2:8d:68c:2s-0 ONLINE 0 0 0 L0 ONLINE 0 0 0 L1 ONLINE 0 0 0 ... U25 ONLINE 0 0 0 U26 ONLINE 0 0 0 spare-53 ONLINE 0 0 0 U27 ONLINE 0 0 0 draid2-0-0 ONLINE 0 0 0 U28 ONLINE 0 0 0 U29 ONLINE 0 0 0 ... U42 ONLINE 0 0 0 U43 ONLINE 0 0 0 special mirror-1 ONLINE 0 0 0 L5 ONLINE 0 0 0 U5 ONLINE 0 0 0 mirror-2 ONLINE 0 0 0 L6 ONLINE 0 0 0 U6 ONLINE 0 0 0 spares draid2-0-0 INUSE currently in use draid2-0-1 AVAIL ``` When adding test coverage for the new dRAID vdev type the following options were added to the ztest command. These options are leverages by zloop.sh to test a wide range of dRAID configurations. -K draid|raidz|random - kind of RAID to test -D <value> - dRAID data drives per group -S <value> - dRAID distributed hot spares -R <value> - RAID parity (raidz or dRAID) The zpool_create, zpool_import, redundancy, replacement and fault test groups have all been updated provide test coverage for the dRAID feature. Co-authored-by: Isaac Huang <[email protected]> Co-authored-by: Mark Maybee <[email protected]> Co-authored-by: Don Brady <[email protected]> Co-authored-by: Matthew Ahrens <[email protected]> Co-authored-by: Brian Behlendorf <[email protected]> Reviewed-by: Mark Maybee <[email protected]> Reviewed-by: Matt Ahrens <[email protected]> Reviewed-by: Tony Hutter <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #10102
* Add prototypesArvind Sankar2020-06-181-0/+2
| | | | | | | | | Add prototypes/move prototypes to header files. Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Arvind Sankar <[email protected]> Closes #10470
* Add AltiVec RAID-ZRomain Dolbeau2020-01-231-1/+4
| | | | | | | | | | | | | Implements the RAID-Z function using AltiVec SIMD. This is basically the NEON code translated to AltiVec. Note that the 'fletcher' algorithm requires 64-bits operations, and the initial implementations of AltiVec (PPC74xx a.k.a. G4, PPC970 a.k.a. G5) only has up to 32-bits operations, so no 'fletcher'. Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Romain Dolbeau <[email protected]> Closes #9539
* Fix typos in include/Andrea Gelmini2019-08-301-1/+1
| | | | | | | Reviewed-by: Ryan Moeller <[email protected]> Reviewed-by: Richard Laager <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Andrea Gelmini <[email protected]> Closes #9238
* Linux 5.0 compat: SIMD compatibilityBrian Behlendorf2019-07-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Restore the SIMD optimization for 4.19.38 LTS, 4.14.120 LTS, and 5.0 and newer kernels. This is accomplished by leveraging the fact that by definition dedicated kernel threads never need to concern themselves with saving and restoring the user FPU state. Therefore, they may use the FPU as long as we can guarantee user tasks always restore their FPU state before context switching back to user space. For the 5.0 and 5.1 kernels disabling preemption and local interrupts is sufficient to allow the FPU to be used. All non-kernel threads will restore the preserved user FPU state. For 5.2 and latter kernels the user FPU state restoration will be skipped if the kernel determines the registers have not changed. Therefore, for these kernels we need to perform the additional step of saving and restoring the FPU registers. Invalidating the per-cpu global tracking the FPU state would force a restore but that functionality is private to the core x86 FPU implementation and unavailable. In practice, restricting SIMD to kernel threads is not a major restriction for ZFS. The vast majority of SIMD operations are already performed by the IO pipeline. The remaining cases are relatively infrequent and can be handled by the generic code without significant impact. The two most noteworthy cases are: 1) Decrypting the wrapping key for an encrypted dataset, i.e. `zfs load-key`. All other encryption and decryption operations will use the SIMD optimized implementations. 2) Generating the payload checksums for a `zfs send` stream. In order to avoid making any changes to the higher layers of ZFS all of the `*_get_ops()` functions were updated to take in to consideration the calling context. This allows for the fastest implementation to be used as appropriate (see kfpu_allowed()). The only other notable instance of SIMD operations being used outside a kernel thread was at module load time. This code was moved in to a taskq in order to accommodate the new kernel thread restriction. Finally, a few other modifications were made in order to further harden this code and facilitate testing. They include updating each implementations operations structure to be declared as a constant. And allowing "cycle" to be set when selecting the preferred ops in the kernel as well as user space. Reviewed-by: Tony Hutter <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #8754 Closes #8793 Closes #8965
* Revert raidz_map and _col structure typesNathaniel Wesley Filardo2018-01-091-17/+17
| | | | | | | | | | | | | | | As part of the refactoring of ab9f4b0b824ab4cc64a4fa382c037f4154de12d6, several uint64_t-s and uint8_t-s were changed to other types. This caused ZoL github issue #6981, an overflow of a size_t on a 32-bit ARM machine. In absense of any strong motivation for the type changes, this simply puts them back, modulo the changes accumulated for ABD. Compile-tested on amd64 and run-tested on armhf. Reviewed-by: Brian Behlendorf <[email protected]> Reviewed-by: Gvozden Neskovic <[email protected]> Signed-off-by: Nathaniel Wesley Filardo <[email protected]> Closes #6981 Closes #7023
* Use cstyle -cpP in `make cstyle` checkBrian Behlendorf2016-12-121-15/+15
| | | | | | | | | | | | | | | | | | | | | | | Enable picky cstyle checks and resolve the new warnings. The vast majority of the changes needed were to handle minor issues with whitespace formatting. This patch contains no functional changes. Non-whitespace changes are as follows: * 8 times ; to { } in for/while loop * fix missing ; in cmd/zed/agents/zfs_diagnosis.c * comment (confim -> confirm) * change endline , to ; in cmd/zpool/zpool_main.c * a number of /* BEGIN CSTYLED */ /* END CSTYLED */ blocks * /* CSTYLED */ markers * change == 0 to ! * ulong to unsigned long in module/zfs/dsl_scan.c * rearrangement of module_param lines in module/zfs/metaslab.c * add { } block around statement after for_each_online_node Reviewed-by: Giuseppe Di Natale <[email protected]> Reviewed-by: Håkan Johansson <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #5465
* DLPX-44812 integrate EP-220 large memory scalabilityDavid Quigley2016-11-291-2/+3
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* Add parity generation/rebuild using AVX-512 for x86-64Romain Dolbeau2016-11-021-0/+6
| | | | | | | | | | | | | | | avx512f should work on all AVX512 hardware, since it only uses Foundation instructions. avx512bw should be faster on hardware supporting the AVW512BW extension. We can use full-width pshufb (instead of relying on the 256 bits AVX2 pshufb). As a side-effect, the code is also unrolled more. Reviewed-by: Richard Laager <[email protected]> Reviewed-by: Gvozden Neskovic <[email protected]> Reviewed-by: Jinshan Xiong <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Romain Dolbeau <[email protected]> Closes #5219
* Add parity generation/rebuild using 128-bits NEON for Aarch64Romain Dolbeau2016-10-031-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This re-use the framework established for SSE2, SSSE3 and AVX2. However, GCC is using FP registers on Aarch64, so unlike SSE/AVX2 we can't rely on the registers being left alone between ASM statements. So instead, the NEON code uses C variables and GCC extended ASM syntax. Note that since the kernel explicitly disable vector registers, they have to be locally re-enabled explicitly. As we use the variable's number to define the symbolic name, and GCC won't allow duplicate symbolic names, numbers have to be unique. Even when the code is not going to be used (e.g. the case for 4 registers when using the macro with only 2). Only the actually used variables should be declared, otherwise the build will fails in debug mode. This requires the replacement of the XOR(X,X) syntax by a new ZERO(X) macro, which does the same thing but without repeating the argument. And perhaps someday there will be a machine where there is a more efficient way to zero a register than XOR with itself. This affects scalar, SSE2, SSSE3 and AVX2 as they need the new macro. It's possible to write faster implementations (different scheduling, different unrolling, interleaving NEON and scalar, ...) for various cores, but this one has the advantage of fitting in the current state of the code, and thus is likely easier to review/check/merge. The only difference between aarch64-neon and aarch64-neonx2 is that aarch64-neonx2 unroll some functions some more. Reviewed-by: Gvozden Neskovic <[email protected]> Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Romain Dolbeau <[email protected]> Closes #4801
* RAIDZ parity kstat reworkGvozden Neskovic2016-07-191-2/+2
| | | | | | | | | Print table with speed of methods for each implementation. Last line describes contents of [fastest] selection. Signed-off-by: Gvozden Neskovic <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #4860
* Fixes and enhancements of SIMD raidz parityGvozden Neskovic2016-07-191-1/+5
| | | | | | | | | | | | | | | | | | | | | | | - Implementation lock replaced with atomic variable - Trailing whitespace is removed from user specified parameter, to enhance experience when using commands that add newline, e.g. `echo` - raidz_test: remove dependency on `getrusage()` and RUSAGE_THREAD, Issue #4813 - silence `cppcheck` in vdev_raidz, partial solution of Issue #1392 - Minor fixes and cleanups - Enable use of original parity methods in [fastest] configuration. New opaque original ops structure, representing native methods, is added to supported raidz methods. Original parity methods are executed if selected implementation has NULL fn pointer. Signed-off-by: Gvozden Neskovic <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Issue #4813 Issue #1392
* Add RAID-Z routines for SSE2 instruction set, in x86_64 mode.Gvozden Neskovic2016-07-131-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The patch covers low-end and older x86 CPUs. Parity generation is equivalent to SSSE3 implementation, but reconstruction is somewhat slower. Previous 'sse' implementation is renamed to 'ssse3' to indicate highest instruction set used. Benchmark results: scalar_rec_p 4 720476442 scalar_rec_q 4 187462804 scalar_rec_r 4 138996096 scalar_rec_pq 4 140834951 scalar_rec_pr 4 129332035 scalar_rec_qr 4 81619194 scalar_rec_pqr 4 53376668 sse2_rec_p 4 2427757064 sse2_rec_q 4 747120861 sse2_rec_r 4 499871637 sse2_rec_pq 4 522403710 sse2_rec_pr 4 464632780 sse2_rec_qr 4 319124434 sse2_rec_pqr 4 205794190 ssse3_rec_p 4 2519939444 ssse3_rec_q 4 1003019289 ssse3_rec_r 4 616428767 ssse3_rec_pq 4 706326396 ssse3_rec_pr 4 570493618 ssse3_rec_qr 4 400185250 ssse3_rec_pqr 4 377541245 original_rec_p 4 691658568 original_rec_q 4 195510948 original_rec_r 4 26075538 original_rec_pq 4 103087368 original_rec_pr 4 15767058 original_rec_qr 4 15513175 original_rec_pqr 4 10746357 Signed-off-by: Gvozden Neskovic <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #4783
* SIMD implementation of vdev_raidz generate and reconstruct routinesGvozden Neskovic2016-06-211-0/+344
This is a new implementation of RAIDZ1/2/3 routines using x86_64 scalar, SSE, and AVX2 instruction sets. Included are 3 parity generation routines (P, PQ, and PQR) and 7 reconstruction routines, for all RAIDZ level. On module load, a quick benchmark of supported routines will select the fastest for each operation and they will be used at runtime. Original implementation is still present and can be selected via module parameter. Patch contains: - specialized gen/rec routines for all RAIDZ levels, - new scalar raidz implementation (unrolled), - two x86_64 SIMD implementations (SSE and AVX2 instructions sets), - fastest routines selected on module load (benchmark). - cmd/raidz_test - verify and benchmark all implementations - added raidz_test to the ZFS Test Suite New zfs module parameters: - zfs_vdev_raidz_impl (str): selects the implementation to use. On module load, the parameter will only accept first 3 options, and the other implementations can be set once module is finished loading. Possible values for this option are: "fastest" - use the fastest math available "original" - use the original raidz code "scalar" - new scalar impl "sse" - new SSE impl if available "avx2" - new AVX2 impl if available See contents of `/sys/module/zfs/parameters/zfs_vdev_raidz_impl` to get the list of supported values. If an implementation is not supported on the system, it will not be shown. Currently selected option is enclosed in `[]`. Signed-off-by: Gvozden Neskovic <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes #4328