Commit Graph

200 Commits

Author SHA1 Message Date
Christoph Hellwig
74cc979c3c block: cleanup how md_autodetect_dev is called
Add a new include/linux/raid/detect.h header to declare the
md_autodetect_dev prototype which can be shared between md and
the partition code.  Then use IS_BUILTIN to call it instead of the
ifdef magic.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-24 07:57:08 -06:00
Zhengyuan Liu
f591df3cc6 md/raid6: fix algorithm choice under larger PAGE_SIZE
There are several algorithms available for raid6 to generate xor and syndrome
parity, including basic int1, int2 ... int32 and SIMD optimized implementation
like sse and neon.  To test and choose the best algorithms at the initial
stage, we need provide enough disk data to feed the algorithms. However, the
disk number we provided depends on page size and gfmul table, seeing bellow:

    const int disks = (65536/PAGE_SIZE) + 2;

So when come to 64K PAGE_SIZE, there is only one data disk plus 2 parity disk,
as a result the chosed algorithm is not reliable. For example, on my arm64
machine with 64K page enabled, it will choose intx32 as the best one, although
the NEON implementation is better.

This patch tries to fix the problem by defining a constant raid6 disk number to
supporting arbitrary page size.

Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Zhengyuan Liu
5e5ac01c2b raid6/test: fix a compilation warning
The compilation warning is redefination showed as following:

        In file included from tables.c:2:
        ../../../include/linux/export.h:180: warning: "EXPORT_SYMBOL" redefined
         #define EXPORT_SYMBOL(sym)  __EXPORT_SYMBOL(sym, "")

        In file included from tables.c:1:
        ../../../include/linux/raid/pq.h:61: note: this is the location of the previous definition
         #define EXPORT_SYMBOL(sym)

Fixes: 69a94abb82 ("export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols")
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Zhengyuan Liu
6b8651aac1 raid6/test: fix a compilation error
The compilation error is redeclaration showed as following:

        In file included from ../../../include/linux/limits.h:6,
                         from /usr/include/x86_64-linux-gnu/bits/local_lim.h:38,
                         from /usr/include/x86_64-linux-gnu/bits/posix1_lim.h:161,
                         from /usr/include/limits.h:183,
                         from /usr/lib/gcc/x86_64-linux-gnu/8/include-fixed/limits.h:194,
                         from /usr/lib/gcc/x86_64-linux-gnu/8/include-fixed/syslimits.h:7,
                         from /usr/lib/gcc/x86_64-linux-gnu/8/include-fixed/limits.h:34,
                         from ../../../include/linux/raid/pq.h:30,
                         from algos.c:14:
        ../../../include/linux/types.h:114:15: error: conflicting types for ‘int64_t’
         typedef s64   int64_t;
                       ^~~~~~~
        In file included from /usr/include/stdint.h:34,
                         from /usr/lib/gcc/x86_64-linux-gnu/8/include/stdint.h:9,
                         from /usr/include/inttypes.h:27,
                         from ../../../include/linux/raid/pq.h:29,
                         from algos.c:14:
        /usr/include/x86_64-linux-gnu/bits/stdint-intn.h:27:19: note: previous \
        declaration of ‘int64_t’ was here
         typedef __int64_t int64_t;

Fixes: 54d50897d5 ("linux/kernel.h: split *_MAX and *_MIN macros into <linux/limits.h>")
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Song Liu <songliubraving@fb.com>
2020-01-13 11:44:09 -08:00
Thomas Gleixner
dd165a658d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 48
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation inc 53 temple place ste 330 boston ma
  02111 1307 usa either version 2 of the license or at your option any
  later version incorporated herein by reference

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 13 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.645641371@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:13 +02:00
Thomas Gleixner
af1a8899d2 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 or at your option any
  later version you should have received a copy of the gnu general
  public license for example usr src linux copying if not write to the
  free software foundation inc 675 mass ave cambridge ma 02139 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 20 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.552543146@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:13 +02:00
Daniel Verkamp
be85f93ae2 lib/raid6: add option to skip algo benchmarking
This is helpful for systems where fast startup time is important.
It is especially nice to avoid benchmarking RAID functions that are
never used (for example, BTRFS selects RAID6_PQ even if the parity RAID
mode is not in use).

This saves 250+ milliseconds of boot time on modern x86 and ARM systems
with a dozen or more available implementations.

The new option is defaulted to 'y' to match the previous behavior of
always benchmarking on init.

Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-12-20 08:53:23 -08:00
Daniel Verkamp
58af3110a7 lib/raid6: avoid __attribute_const__ redefinition
This is defined in glibc's sys/cdefs.h on my system with the same
definition as the raid6test fallback definition.  Add a #ifndef check to
avoid a compiler warning about redefining it.

Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-12-20 08:53:23 -08:00
Daniel Verkamp
e731f3e28b lib/raid6: add missing include for raid6test
Add #include <sys/time.h> for gettimeofday() to fix the compiler warning
about an implicitly defined functions.

Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-12-20 08:53:23 -08:00
Linus Torvalds
49a695ba72 powerpc updates for 4.17
Notable changes:
 
  - Support for 4PB user address space on 64-bit, opt-in via mmap().
 
  - Removal of POWER4 support, which was accidentally broken in 2016 and no one
    noticed, and blocked use of some modern instructions.
 
  - Workarounds so that the hypervisor can enable Transactional Memory on Power9.
 
  - A series to disable the DAWR (Data Address Watchpoint Register) on Power9.
 
  - More information displayed in the meltdown/spectre_v1/v2 sysfs files.
 
  - A vpermxor (Power8 Altivec) implementation for the raid6 Q Syndrome.
 
  - A big series to make the allocation of our pacas (per cpu area), kernel page
    tables, and per-cpu stacks NUMA aware when using the Radix MMU on Power9.
 
 And as usual many fixes, reworks and cleanups.
 
 Thanks to:
   Aaro Koskinen, Alexandre Belloni, Alexey Kardashevskiy, Alistair Popple, Andy
   Shevchenko, Aneesh Kumar K.V, Anshuman Khandual, Balbir Singh, Benjamin
   Herrenschmidt, Christophe Leroy, Christophe Lombard, Cyril Bur, Daniel Axtens,
   Dave Young, Finn Thain, Frederic Barrat, Gustavo Romero, Horia Geantă,
   Jonathan Neuschäfer, Kees Cook, Larry Finger, Laurent Dufour, Laurent Vivier,
   Logan Gunthorpe, Madhavan Srinivasan, Mark Greer, Mark Hairgrove, Markus
   Elfring, Mathieu Malaterre, Matt Brown, Matt Evans, Mauricio Faria de
   Oliveira, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Paul Mackerras,
   Philippe Bergheaud, Ram Pai, Rob Herring, Sam Bobroff, Segher Boessenkool,
   Simon Guo, Simon Horman, Stewart Smith, Sukadev Bhattiprolu, Suraj Jitindar
   Singh, Thiago Jung Bauermann, Vaibhav Jain, Vaidyanathan Srinivasan, Vasant
   Hegde, Wei Yongjun.
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Merge tag 'powerpc-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Support for 4PB user address space on 64-bit, opt-in via mmap().

   - Removal of POWER4 support, which was accidentally broken in 2016
     and no one noticed, and blocked use of some modern instructions.

   - Workarounds so that the hypervisor can enable Transactional Memory
     on Power9.

   - A series to disable the DAWR (Data Address Watchpoint Register) on
     Power9.

   - More information displayed in the meltdown/spectre_v1/v2 sysfs
     files.

   - A vpermxor (Power8 Altivec) implementation for the raid6 Q
     Syndrome.

   - A big series to make the allocation of our pacas (per cpu area),
     kernel page tables, and per-cpu stacks NUMA aware when using the
     Radix MMU on Power9.

  And as usual many fixes, reworks and cleanups.

  Thanks to: Aaro Koskinen, Alexandre Belloni, Alexey Kardashevskiy,
  Alistair Popple, Andy Shevchenko, Aneesh Kumar K.V, Anshuman Khandual,
  Balbir Singh, Benjamin Herrenschmidt, Christophe Leroy, Christophe
  Lombard, Cyril Bur, Daniel Axtens, Dave Young, Finn Thain, Frederic
  Barrat, Gustavo Romero, Horia Geantă, Jonathan Neuschäfer, Kees Cook,
  Larry Finger, Laurent Dufour, Laurent Vivier, Logan Gunthorpe,
  Madhavan Srinivasan, Mark Greer, Mark Hairgrove, Markus Elfring,
  Mathieu Malaterre, Matt Brown, Matt Evans, Mauricio Faria de Oliveira,
  Michael Neuling, Naveen N. Rao, Nicholas Piggin, Paul Mackerras,
  Philippe Bergheaud, Ram Pai, Rob Herring, Sam Bobroff, Segher
  Boessenkool, Simon Guo, Simon Horman, Stewart Smith, Sukadev
  Bhattiprolu, Suraj Jitindar Singh, Thiago Jung Bauermann, Vaibhav
  Jain, Vaidyanathan Srinivasan, Vasant Hegde, Wei Yongjun"

* tag 'powerpc-4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (207 commits)
  powerpc/64s/idle: Fix restore of AMOR on POWER9 after deep sleep
  powerpc/64s: Fix POWER9 DD2.2 and above in cputable features
  powerpc/64s: Fix pkey support in dt_cpu_ftrs, add CPU_FTR_PKEY bit
  powerpc/64s: Fix dt_cpu_ftrs to have restore_cpu clear unwanted LPCR bits
  Revert "powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead"
  powerpc: iomap.c: introduce io{read|write}64_{lo_hi|hi_lo}
  powerpc: io.h: move iomap.h include so that it can use readq/writeq defs
  cxl: Fix possible deadlock when processing page faults from cxllib
  powerpc/hw_breakpoint: Only disable hw breakpoint if cpu supports it
  powerpc/mm/radix: Update command line parsing for disable_radix
  powerpc/mm/radix: Parse disable_radix commandline correctly.
  powerpc/mm/hugetlb: initialize the pagetable cache correctly for hugetlb
  powerpc/mm/radix: Update pte fragment count from 16 to 256 on radix
  powerpc/mm/keys: Update documentation and remove unnecessary check
  powerpc/64s/idle: POWER9 ESL=0 stop avoid save/restore overhead
  powerpc/64s/idle: Consolidate power9_offline_stop()/power9_idle_stop()
  powerpc/powernv: Always stop secondaries before reboot/shutdown
  powerpc: hard disable irqs in smp_send_stop loop
  powerpc: use NMI IPI for smp_send_stop
  powerpc/powernv: Fix SMT4 forcing idle code
  ...
2018-04-07 12:08:19 -07:00
Arnd Bergmann
889ce12b16 raid: remove tile specific raid6 implementation
The Tile architecture is getting removed, so we no longer need this either.

Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-26 15:56:28 +02:00
Matt Brown
751ba79cc5 lib/raid6/altivec: Add vpermxor implementation for raid6 Q syndrome
This patch uses the vpermxor instruction to optimise the raid6 Q
syndrome. This instruction was made available with POWER8, ISA version
2.07. It allows for both vperm and vxor instructions to be done in a
single instruction. This has been tested for correctness on a ppc64le
vm with a basic RAID6 setup containing 5 drives.

The performance benchmarks are from the raid6test in the
/lib/raid6/test directory. These results are from an IBM Firestone
machine with ppc64le architecture. The benchmark results show a 35%
speed increase over the best existing algorithm for powerpc (altivec).
The raid6test has also been run on a big-endian ppc64 vm to ensure it
also works for big-endian architectures.

Performance benchmarks:
  raid6: altivecx4 gen() 18773 MB/s
  raid6: altivecx8 gen() 19438 MB/s

  raid6: vpermxor4 gen() 25112 MB/s
  raid6: vpermxor8 gen() 26279 MB/s

Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com>
Reviewed-by: Daniel Axtens <dja@axtens.net>
[mpe: Add VPERMXOR macro so we can build with old binutils]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-20 16:47:25 +11:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Ard Biesheuvel
6ec4e2514d md/raid6: implement recovery using ARM NEON intrinsics
Provide a NEON accelerated implementation of the recovery algorithm,
which supersedes the default byte-by-byte one.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-09 18:52:07 +01:00
Anup Patel
b5dceda1f7 lib/raid6: Add log-of-2 table for RAID6 HW requiring disk position
The raid6_gfexp table represents {2}^n values for 0 <= n < 256. The
Linux async_tx framework pass values from raid6_gfexp as coefficients
for each source to prep_dma_pq() callback of DMA channel with PQ
capability. This creates problem for RAID6 offload engines (such as
Broadcom SBA) which take disk position (i.e. log of {2}) instead of
multiplicative cofficients from raid6_gfexp table.

This patch adds raid6_gflog table having log-of-2 value for any given
x such that 0 <= x < 256. For any given disk coefficient x, the
corresponding disk position is given by raid6_gflog[x]. The RAID6
offload engine driver can use this newly added raid6_gflog table to
get disk position from multiplicative coefficient.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Shaohua Li <shli@fb.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-05-16 10:01:57 +05:30
Linus Torvalds
c23112e039 Merge tag 'md/4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md
Pull MD updates from Shaohua Li:
 "This update includes:

   - new AVX512 instruction based raid6 gen/recovery algorithm

   - a couple of md-cluster related bug fixes

   - fix a potential deadlock

   - set nonrotational bit for raid array with SSD

   - set correct max_hw_sectors for raid5/6, which hopefuly can improve
     performance a little bit

   - other minor fixes"

* tag 'md/4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  md: set rotational bit
  raid6/test/test.c: bug fix: Specify aligned(alignment) attributes to the char arrays
  raid5: handle register_shrinker failure
  raid5: fix to detect failure of register_shrinker
  md: fix a potential deadlock
  md/bitmap: fix wrong cleanup
  raid5: allow arbitrary max_hw_sectors
  lib/raid6: Add AVX512 optimized xor_syndrome functions
  lib/raid6/test/Makefile: Add avx512 gen_syndrome and recovery functions
  lib/raid6: Add AVX512 optimized recovery functions
  lib/raid6: Add AVX512 optimized gen_syndrome functions
  md-cluster: make resync lock also could be interruptted
  md-cluster: introduce dlm_lock_sync_interruptible to fix tasks hang
  md-cluster: convert the completion to wait queue
  md-cluster: protect md_find_rdev_nr_rcu with rcu lock
  md-cluster: clean related infos of cluster
  md: changes for MD_STILL_CLOSED flag
  md-cluster: remove some unnecessary dlm_unlock_sync
  md-cluster: use FORCEUNLOCK in lockres_free
  md-cluster: call md_kick_rdev_from_array once ack failed
2016-10-07 09:45:43 -07:00
Gayatri Kammela
13c520b299 lib/raid6: Add AVX512 optimized recovery functions
Optimize RAID6 recovery functions to take advantage of
the 512-bit ZMM integer instructions introduced in AVX512.

AVX512 optimized recovery functions, which is simply based
on recov_avx2.c written by Jim Kukunas

This patch was tested and benchmarked before submission on
a hardware that has AVX512 flags to support such instructions

Cc: Jim Kukunas <james.t.kukunas@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Megha Dey <megha.dey@linux.intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21 09:09:44 -07:00
Gayatri Kammela
e0a491c129 lib/raid6: Add AVX512 optimized gen_syndrome functions
Optimize RAID6 gen_syndrom functions to take advantage of
the 512-bit ZMM integer instructions introduced in AVX512.

AVX512 optimized gen_syndrom functions, which is simply based
on avx2.c written by Yuanhan Liu and sse2.c written by hpa.

The patch was tested and benchmarked before submission on
a hardware that has AVX512 flags to support such instructions

Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jim Kukunas <james.t.kukunas@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Megha Dey <megha.dey@linux.intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-09-21 09:09:44 -07:00
Martin Schwidefsky
f5b55fa1f8 RAID/s390: provide raid6 recovery optimization
The XC instruction can be used to improve the speed of the raid6
recovery. The loops now operate on blocks of 256 bytes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-01 16:13:25 +02:00
Martin Schwidefsky
474fd6e80f RAID/s390: add SIMD implementation for raid6 gen/xor
Using vector registers is slightly faster:

raid6: vx128x8  gen() 19705 MB/s
raid6: vx128x8  xor() 11886 MB/s
raid6: using algorithm vx128x8 gen() 19705 MB/s
raid6: .... xor() 11886 MB/s, rmw enabled

vs the software algorithms:

raid6: int64x1  gen()  3018 MB/s
raid6: int64x1  xor()  1429 MB/s
raid6: int64x2  gen()  4661 MB/s
raid6: int64x2  xor()  3143 MB/s
raid6: int64x4  gen()  5392 MB/s
raid6: int64x4  xor()  3509 MB/s
raid6: int64x8  gen()  4441 MB/s
raid6: int64x8  xor()  3207 MB/s
raid6: using algorithm int64x4 gen() 5392 MB/s
raid6: .... xor() 3509 MB/s, rmw enabled

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-29 11:05:04 +02:00
Gayatri Kammela
6a84f57241 raid6/algos.c : bug fix : Add the missing definitions to the pq.h file
Adding these pr_info and pr_err definitions so as to allow code to be
compiled successfully for testing in userspace, since the printk has
been replaced by pr_info and pr_err in algos.c

Absence of these definitions result in the compilation errors
such as ' undefined reference to `pr_info' ' ' undefined reference to
`pr_err' '

Cc: NeilBrown <neilb@suse.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-01-21 14:47:08 -08:00
Markus Stockhausen
fe5cbc6e06 md/raid6 algorithms: delta syndrome functions
v3: s-o-b comment, explanation of performance and descision for
the start/stop implementation

Implementing rmw functionality for RAID6 requires optimized syndrome
calculation. Up to now we can only generate a complete syndrome. The
target P/Q pages are always overwritten. With this patch we provide
a framework for inplace P/Q modification. In the first place simply
fill those functions with NULL values.

xor_syndrome() has two additional parameters: start & stop. These
will indicate the first and last page that are changing during a
rmw run. That makes it possible to avoid several unneccessary loops
and speed up calculation. The caller needs to implement the following
logic to make the functions work.

1) xor_syndrome(disks, start, stop, ...): "Remove" all data of source
blocks inside P/Q between (and including) start and end.

2) modify any block with start <= block <= stop

3) xor_syndrome(disks, start, stop, ...): "Reinsert" all data of
source blocks into P/Q between (and including) start and end.

Pages between start and stop that won't be changed should be filled
with a pointer to the kernel zero page. The reasons for not taking NULL
pages are:

1) Algorithms cross the whole source data line by line. Thus avoid
additional branches.

2) Having a NULL page avoids calculating the XOR P parity but still
need calulation steps for the Q parity. Depending on the algorithm
unrolling that might be only a difference of 2 instructions per loop.

The benchmark numbers of the gen_syndrome() functions are displayed in
the kernel log. Do the same for the xor_syndrome() functions. This
will help to analyze performance problems and give an rough estimate
how well the algorithm works. The choice of the fastest algorithm will
still depend on the gen_syndrome() performance.

With the start/stop page implementation the speed can vary a lot in real
life. E.g. a change of page 0 & page 15 on a stripe will be harder to
compute than the case where page 0 & page 1 are XOR candidates. To be not
to enthusiatic about the expected speeds we will run a worse case test
that simulates a change on the upper half of the stripe. So we do:

1) calculation of P/Q for the upper pages

2) continuation of Q for the lower (empty) pages

Signed-off-by: Markus Stockhausen <stockhausen@collogia.de>
Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-22 08:00:41 +10:00
Linus Torvalds
4d7696f1b0 md update for v3.12
Headline item is multithreading for RAID5 so that more
 IO/sec can be supported on fast (SSD) devices.
 Also TILE-Gx SIMD suppor for RAID6 calculations and an
 assortment of bug fixes.
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Merge tag 'md/3.12' of git://neil.brown.name/md

Pull md update from Neil Brown:
 "Headline item is multithreading for RAID5 so that more IO/sec can be
  supported on fast (SSD) devices.  Also TILE-Gx SIMD suppor for RAID6
  calculations and an assortment of bug fixes"

* tag 'md/3.12' of git://neil.brown.name/md:
  raid5: only wakeup necessary threads
  md/raid5: flush out all pending requests before proceeding with reshape.
  md/raid5: use seqcount to protect access to shape in make_request.
  raid5: sysfs entry to control worker thread number
  raid5: offload stripe handle to workqueue
  raid5: fix stripe release order
  raid5: make release_stripe lockless
  md: avoid deadlock when dirty buffers during md_stop.
  md: Don't test all of mddev->flags at once.
  md: Fix apparent cut-and-paste error in super_90_validate
  raid6/test: replace echo -e with printf
  RAID: add tilegx SIMD implementation of raid6
  md: fix safe_mode buglet.
  md: don't call md_allow_write in get_bitmap_file.
2013-09-10 13:03:41 -07:00
Ken Steele
ae77cbc1e7 RAID: add tilegx SIMD implementation of raid6
This change adds TILE-Gx SIMD instructions to the software raid
(md), modeling the Altivec implementation. This is only for Syndrome
generation; there is more that could be done to improve recovery,
as in the recent Intel SSE3 recovery implementation.

The code unrolls 8 times; this turns out to be the best on tilegx
hardware among the set 1, 2, 4, 8 or 16.  The code reads one
cache-line of data from each disk, stores P and Q then goes to the
next cache-line.

The test code in sys/linux/lib/raid6/test reports 2008 MB/s data
read rate for syndrome generation using 18 disks (16 data and 2
parity). It was 1512 MB/s before this SIMD optimizations. This is
running on 1 core with all the data in cache.

This is based on the paper The Mathematics of RAID-6.
(http://kernel.org/pub/linux/kernel/people/hpa/raid6.pdf).

Signed-off-by: Ken Steele <ken@tilera.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2013-08-27 16:05:50 +10:00
Ard Biesheuvel
7d11965ddb lib/raid6: add ARM-NEON accelerated syndrome calculation
Rebased/reworked a patch contributed by Rob Herring that uses
NEON intrinsics to perform the RAID-6 syndrome calculations.
It uses the existing unroll.awk code to generate several
unrolled versions of which the best performing one is selected
at boot time.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Cc: hpa@linux.intel.com
2013-07-08 22:09:18 +01:00
David Howells
3d33fcc11b UAPI: Remove empty Kbuild files
Empty files can get deleted by the patch program, so remove empty Kbuild
files and their links from the parent Kbuilds.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-01-02 17:36:10 -08:00
Yuanhan Liu
2c935842bd lib/raid6: Add AVX2 optimized gen_syndrome functions
Add AVX2 optimized gen_syndrom functions, which is simply based on
sse2.c written by hpa.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Jim Kukunas <james.t.kukunas@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2012-12-13 19:51:03 +11:00
Jim Kukunas
7056741fd9 lib/raid6: Add AVX2 optimized recovery functions
Optimize RAID6 recovery functions to take advantage of
the 256-bit YMM integer instructions introduced in AVX2.

The patch was tested and benchmarked before submission.
However hardware is not yet released so benchmark numbers
cannot be reported.

Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Jim Kukunas <james.t.kukunas@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2012-12-13 16:42:01 +11:00
David Howells
fc5a40a230 UAPI: (Scripted) Disintegrate include/linux/raid
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-10-09 09:49:02 +01:00
Jim Kukunas
048a8b8c89 lib/raid6: Add SSSE3 optimized recovery functions
Add SSSE3 optimized recovery functions, as well as a system
for selecting the most appropriate recovery functions to use.

Originally-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Jim Kukunas <james.t.kukunas@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2012-05-22 13:54:18 +10:00
NeilBrown
c6563a8c38 md: add possibility to change data-offset for devices.
When reshaping we can avoid costly intermediate backup by
changing the 'start' address of the array on the device
(if there is enough room).

So as a first step, allow such a change to be requested
through sysfs, and recorded in v1.x metadata.

(As we didn't previous check that all 'pad' fields were zero,
 we need a new FEATURE flag for this.
 A (belatedly) check that all remaining 'pad' fields are
 zero to avoid a repeat of this)

The new data offset must be requested separately for each device.
This allows each to have a different change in the data offset.
This is not likely to be used often but as data_offset can be
set per-device, new_data_offset should be too.

This patch also removes the 'acknowledged' arg to rdev_set_badblocks as
it is never used and never will be.  At the same time we add a new
arg ('in_new') which is currently always zero but will be used more
soon.

When a reshape finishes we will need to update the data_offset
and rdev->sectors.  So provide an exported function to do that.

Signed-off-by: NeilBrown <neilb@suse.de>
2012-05-21 09:27:00 +10:00
NeilBrown
2c810cddc4 md: allow a reshape operation to be reversed.
Currently a reshape operation always progresses from the start
of the array to the end unless the number of devices is being
reduced, in which case it progressed in the opposite direction.

To reverse a partial reshape which changes the number of devices
you can stop the array and re-assemble with the raid-disks numbers
reversed and it will undo.

However for a reshape that does not change the number of devices
it is not possible to reverse the reshape in the middle - you have to
wait until it completes.

So add a 'reshape_direction' attribute with is either 'forwards' or
'backwards' and can be explicitly set when delta_disks is zero.

This will become more important when we allow the data_offset to
change in a reshape.  Then the explicit statement of what direction is
being used will be more useful.

This can be enabled in raid5 trivially as it already supports
reverse reshape and just needs to use a different trigger to request it.

Signed-off-by: NeilBrown <neilb@suse.de>
2012-05-21 09:27:00 +10:00
majianpeng
43437ecd5a md: Use existed macros instead of numbers
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2012-03-13 11:21:23 +11:00
NeilBrown
2d78f8c451 md: create externally visible flags for supporting hot-replace.
hot-replace is a feature being added to md which will allow a
device to be replaced without removing it from the array first.

With hot-replace a spare can be activated and recovery can start while
the original device is still in place, thus allowing a transition from
an unreliable device to a reliable device without leaving the array
degraded during the transition.  It can also be use when the original
device is still reliable but it not wanted for some reason.

This will eventually be supported in RAID4/5/6 and RAID10.

This patch adds a super-block flag to distinguish the replacement
device.  If an old kernel sees this flag it will reject the device.

It also adds two per-device flags which are viewable and settable via
sysfs.
   "want_replacement" can be set to request that a device be replaced.
   "replacement" is set to show that this device is replacing another
   device.

The "rd%d" links in /sys/block/mdXx/md only apply to the original
device, not the replacement.  We currently don't make links for the
replacement - there doesn't seem to be a need.

Signed-off-by: NeilBrown <neilb@suse.de>
2011-12-23 10:17:51 +11:00
Steven Rostedt
38059ec2bd md: Fix userspace free_pages() macro
While using etags to find free_pages(), I stumbled across this debug
definition of free_pages() that is to be used while debugging some raid
code in userspace. The __get_free_pages() allocates the correct size,
but the free_pages() does not match. free_pages(), like
__get_free_pages(), takes an order and not a size.

Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: NeilBrown <neilb@suse.de>
2011-12-23 10:17:51 +11:00
NeilBrown
2699b67223 md: load/store badblock list from v1.x metadata
Space must have been allocated when array was created.
A feature flag is set when the badblock list is non-empty, to
ensure old kernels don't load and trust the whole device.

We only update the on-disk badblocklist when it has changed.
If the badblocklist (or other metadata) is stored on a bad block, we
don't cope very well.

If metadata has no room for bad block, flag bad-blocks as disabled,
and do the same for 0.90 metadata.

Signed-off-by: NeilBrown <neilb@suse.de>
2011-07-28 11:31:47 +10:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
NeilBrown
d5302fe41f Make lib/raid6/test build correctly.
Some bit-rot needs to be cleaned out.

Signed-off-by: NeilBrown <neilb@suse.de>
2010-08-12 06:38:24 +10:00
NeilBrown
7820f9e1dd md: remove sparse warning:symbol XXX was not declared.
Signed-off-by: NeilBrown <neilb@suse.de>
2009-12-14 12:49:47 +11:00
Andre Noll
cdc2ae6d6a md: fix some comments.
1/ Raid5 has learned to take over also raid4 and raid6 arrays.
2/ new_chunk in mdp_superblock_1 is in sectors, not bytes.

Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18 08:46:47 +10:00
Dan Williams
f701d589aa md/raid6: move raid6 data processing to raid6_pq.ko
Move the raid6 data processing routines into a standalone module
(raid6_pq) to prepare them to be called from async_tx wrappers and other
non-md drivers/modules.  This precludes a circular dependency of raid456
needing the async modules for data processing while those modules in
turn depend on raid456 for the base level synchronous raid6 routines.

To support this move:
1/ The exportable definitions in raid6.h move to include/linux/raid/pq.h
2/ The raid6_call, recovery calls, and table symbols are exported
3/ Extra #ifdef __KERNEL__ statements to enable the userspace raid6test to
   compile

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 15:09:39 +11:00
NeilBrown
43b2e5d86d md: move md_k.h from include/linux/raid/ to drivers/md/
It really is nicer to keep related code together..

Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 14:33:13 +11:00
NeilBrown
bff61975b3 md: move lots of #include lines out of .h files and into .c
This makes the includes more explicit, and is preparation for moving
md_k.h to drivers/md/md.h

Remove include/raid/md.h as its only remaining use was to #include
other files.

Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 14:33:13 +11:00
NeilBrown
92022950c6 md: move most content from md.h to md_k.h
The extern function definitions are kernel-internal definitions, so
they belong in md_k.h

The MD_*_VERSION values could reasonably go in a number of places,
but md_u.h seems most reasonable.

This leaves almost nothing in md.h.  It will go soon.

Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 14:33:13 +11:00
NeilBrown
8b2b5c217c md: move LEVEL_* definition from md_k.h to md_u.h
.. as they are part of the user-space interface.
Also move MdpMinorShift into there so we can remove duplication.

Lastly move mdp_major in.  It is less obviously part of the user-space
interface, but do_mounts_md.c uses it, and it is acting a bit like
user-space.

Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 14:27:03 +11:00
Christoph Hellwig
ef740c372d md: move headers out of include/linux/raid/
Move the headers with the local structures for the disciplines and
bitmap.h into drivers/md/ so that they are more easily grepable for
hacking and not far away.  md.h is left where it is for now as there
are some uses from the outside.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 14:27:03 +11:00
NeilBrown
eea1bf384e md: Fix is_mddev_idle test (again).
There are two problems with is_mddev_idle.

1/ sync_io is 'atomic_t' and hence 'int'.  curr_events and all the
   rest are 'long'.
   So if sync_io were to wrap on a 64bit host, the value of
   curr_events would go very negative suddenly, and take a very
   long time to return to positive.

   So do all calculations as 'int'.  That gives us plenty of precision
   for what we need.

2/ To initialise rdev->last_events we simply call is_mddev_idle, on
   the assumption that it will make sure that last_events is in a
   suitable range.  It used to do this, but now it does not.
   So now we need to be more explicit about initialisation.

Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31 14:27:02 +11:00
Jaswinder Singh Rajput
bcf74582af headers_check fix: raid/md_p.h
fix the following 'make headers_check' warning:

  usr/include/linux/raid/md_p.h:85: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
2009-01-30 23:32:45 +05:30
NeilBrown
4044ba58dd md: don't retry recovery of raid1 that fails due to error on source drive.
If a raid1 has only one working drive and it has a sector which
gives an error on read, then an attempt to recover onto a spare will
fail, but as the single remaining drive is not removed from the
array, the recovery will be immediately re-attempted, resulting
in an infinite recovery loop.

So detect this situation and don't retry recovery once an error
on the lone remaining drive is detected.

Allow recovery to be retried once every time a spare is added
in case the problem wasn't actually a media error.

Signed-off-by: NeilBrown <neilb@suse.de>
2009-01-09 08:31:11 +11:00
NeilBrown
efeb53c0e5 md: Allow md devices to be created by name.
Using sequential numbers to identify md devices is somewhat artificial.
Using names can be a lot more user-friendly.

Also, creating md devices by opening the device special file is a bit
awkward.

So this patch provides a new option for creating and naming devices.

Writing a name such as "md_home" to
    /sys/modules/md_mod/parameters/new_array
will cause an array with that name to be created.  It will appear in
/sys/block/ /proc/partitions and /proc/mdstat as 'md_home'.
It will have an arbitrary minor number allocated.

md devices that a created by an open are destroyed on the last
close when the device is inactive.
For named md devices, they will not be destroyed until the array
is explicitly stopped, either with the STOP_ARRAY ioctl or by
writing 'clear' to /sys/block/md_XXXX/md/array_state.

The name of the array must start 'md_' to avoid conflict with
other devices.

Signed-off-by: NeilBrown <neilb@suse.de>
2009-01-09 08:31:10 +11:00