Commit Graph

23 Commits

Author SHA1 Message Date
Tony Hutter
786641dcf9
Workaround UBSAN errors for variable arrays
This gets around UBSAN errors when using arrays at the end of
structs.  It converts some zero-length arrays to variable length
arrays and disables UBSAN checking on certain modules.

It is based off of the patch from #15460.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Co-authored-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Issue #15145
Closes #15510
2023-11-12 16:26:07 -08:00
Don Brady
5caeef02fa
RAID-Z expansion feature
This feature allows disks to be added one at a time to a RAID-Z group,
expanding its capacity incrementally.  This feature is especially useful
for small pools (typically with only one RAID-Z group), where there
isn't sufficient hardware to add capacity by adding a whole new RAID-Z
group (typically doubling the number of disks).

== Initiating expansion ==

A new device (disk) can be attached to an existing RAIDZ vdev, by
running `zpool attach POOL raidzP-N NEW_DEVICE`, e.g. `zpool attach tank
raidz2-0 sda`.  The new device will become part of the RAIDZ group.  A
"raidz expansion" will be initiated, and the new device will contribute
additional space to the RAIDZ group once the expansion completes.

The `feature@raidz_expansion` on-disk feature flag must be `enabled` to
initiate an expansion, and it remains `active` for the life of the pool.
In other words, pools with expanded RAIDZ vdevs can not be imported by
older releases of the ZFS software.

== During expansion ==

The expansion entails reading all allocated space from existing disks in
the RAIDZ group, and rewriting it to the new disks in the RAIDZ group
(including the newly added device).

The expansion progress can be monitored with `zpool status`.

Data redundancy is maintained during (and after) the expansion.  If a
disk fails while the expansion is in progress, the expansion pauses
until the health of the RAIDZ vdev is restored (e.g. by replacing the
failed disk and waiting for reconstruction to complete).

The pool remains accessible during expansion.  Following a reboot or
export/import, the expansion resumes where it left off.

== After expansion ==

When the expansion completes, the additional space is available for use,
and is reflected in the `available` zfs property (as seen in `zfs list`,
`df`, etc).

Expansion does not change the number of failures that can be tolerated
without data loss (e.g. a RAIDZ2 is still a RAIDZ2 even after
expansion).

A RAIDZ vdev can be expanded multiple times.

After the expansion completes, old blocks remain with their old
data-to-parity ratio (e.g. 5-wide RAIDZ2, has 3 data to 2 parity), but
distributed among the larger set of disks.  New blocks will be written
with the new data-to-parity ratio (e.g. a 5-wide RAIDZ2 which has been
expanded once to 6-wide, has 4 data to 2 parity).  However, the RAIDZ
vdev's "assumed parity ratio" does not change, so slightly less space
than is expected may be reported for newly-written blocks, according to
`zfs list`, `df`, `ls -s`, and similar tools.

Sponsored-by: The FreeBSD Foundation
Sponsored-by: iXsystems, Inc.
Sponsored-by: vStack
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Authored-by: Matthew Ahrens <mahrens@delphix.com>
Contributions-by: Fedor Uporov <fuporov.vstack@gmail.com>
Contributions-by: Stuart Maybee <stuart.maybee@comcast.net>
Contributions-by: Thorsten Behrens <tbehrens@outlook.com>
Contributions-by: Fmstrat <nospam@nowsci.com>
Contributions-by: Don Brady <dev.fs.zfs@gmail.com>
Signed-off-by: Don Brady <dev.fs.zfs@gmail.com>
Closes #15022
2023-11-08 10:19:41 -08:00
Richard Yao
11df48ab8b
Cleanup Raid-Z Typo fixes
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #13834
2022-09-06 09:43:21 -07:00
Tino Reichardt
1d3ba0bf01
Replace dead opensolaris.org license link
The commit replaces all findings of the link:
http://www.opensolaris.org/os/licensing with this one:
https://opensource.org/licenses/CDDL-1.0

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tino Reichardt <milky-zfs@mcmilk.de>
Closes #13619
2022-07-11 14:16:13 -07:00
наб
18168da727
module/*.ko: prune .data, global .rodata
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 <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12899
2022-01-14 15:37:55 -08:00
Brian Behlendorf
8fb577ae6d
Fix dRAID sequential resilver silent damage handling
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 <mark.maybee@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #12061
2021-05-20 15:05:26 -07:00
Matthew Ahrens
330c6c0523
Clean up RAIDZ/DRAID ereport code
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 <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #11735
2021-03-19 16:22:10 -07:00
Matthew Ahrens
46df6e98aa
Remove unused rr_code
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 <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #11736
2021-03-17 21:57:09 -07:00
Matthew Ahrens
e2af2acce3
allow callers to allocate and provide the abd_t struct
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 <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Issue #8853 
Closes #11439
2021-01-20 11:24:37 -08:00
Brian Behlendorf
b2255edcc0
Distributed Spare (dRAID) Feature
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 <he.huang@intel.com>
Co-authored-by: Mark Maybee <mmaybee@cray.com>
Co-authored-by: Don Brady <don.brady@delphix.com>
Co-authored-by: Matthew Ahrens <mahrens@delphix.com>
Co-authored-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mmaybee@cray.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #10102
2020-11-13 13:51:51 -08:00
Arvind Sankar
0ce2de637b Add prototypes
Add prototypes/move prototypes to header files.

Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Closes #10470
2020-06-18 12:21:32 -07:00
Romain Dolbeau
35b07497c6 Add AltiVec RAID-Z
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 <behlendorf1@llnl.gov>
Signed-off-by: Romain Dolbeau <romain.dolbeau@european-processor-initiative.eu>
Closes #9539
2020-01-23 11:01:24 -08:00
Andrea Gelmini
cf7c5a030e Fix typos in include/
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #9238
2019-08-30 09:53:15 -07:00
Brian Behlendorf
e5db313494
Linux 5.0 compat: SIMD compatibility
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 <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8754 
Closes #8793 
Closes #8965
2019-07-12 09:31:20 -07:00
Nathaniel Wesley Filardo
cba6fc61a2 Revert raidz_map and _col structure types
As part of the refactoring of ab9f4b0b82,
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 <behlendorf1@llnl.gov>
Reviewed-by: Gvozden Neskovic <neskovic@gmail.com>
Signed-off-by: Nathaniel Wesley Filardo <nwf@cs.jhu.edu>
Closes #6981 
Closes #7023
2018-01-09 14:46:52 -08:00
Brian Behlendorf
02730c333c Use cstyle -cpP in make cstyle check
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 <dinatale2@llnl.gov>
Reviewed-by: Håkan Johansson <f96hajo@chalmers.se>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #5465
2016-12-12 10:46:26 -08:00
David Quigley
a6255b7fce DLPX-44812 integrate EP-220 large memory scalability 2016-11-29 14:34:27 -08:00
Romain Dolbeau
7f547f85fe Add parity generation/rebuild using AVX-512 for x86-64
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 <rlaager@wiktel.com>
Reviewed-by: Gvozden Neskovic <neskovic@gmail.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Romain Dolbeau <romain.github@dolbeau.name>
Closes #5219
2016-11-02 12:40:23 -07:00
Romain Dolbeau
62a65a654e Add parity generation/rebuild using 128-bits NEON for Aarch64
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 <neskovic@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Romain Dolbeau <romain.dolbeau@atos.net>
Closes #4801
2016-10-03 09:44:00 -07:00
Gvozden Neskovic
26a08b5ca9 RAIDZ parity kstat rework
Print table with speed of methods for each implementation.
Last line describes contents of [fastest] selection.

Signed-off-by: Gvozden Neskovic <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4860
2016-07-19 16:43:07 -07:00
Gvozden Neskovic
c9187d867f Fixes and enhancements of SIMD raidz parity
- 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 <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4813
Issue #1392
2016-07-19 16:43:07 -07:00
Gvozden Neskovic
ae25d22235 Add RAID-Z routines for SSE2 instruction set, in x86_64 mode.
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 <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4783
2016-07-13 10:24:55 -07:00
Gvozden Neskovic
ab9f4b0b82 SIMD implementation of vdev_raidz generate and reconstruct routines
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 <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4328
2016-06-21 09:27:26 -07:00