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vcc_3v3_reg is a fixed regulator and doesn't need a reg property. Remove
its unit-address.
Solves:
Warning (unit_address_vs_reg): Node /fixedregulator@0 has a unit name, but no reg property
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Remove the unit-address from the oneiwire node as it doesn't have a reg
property.
Solves:
Warning (unit_address_vs_reg): Node /onewire@0 has a unit name, but no reg property
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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vcc_mmc1_reg is a fixed regulators and doesn't need a reg property. Remove
its unit-address.
Solves:
Warning (unit_address_vs_reg): Node /fixedregulator@2 has a unit name, but no reg property
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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vcc_3v3_reg and vcc_mmc1_reg are fixed regulators and don't need a
reg property. Remove their unit-address.
Solves:
Warning (unit_address_vs_reg): Node /fixedregulator@0 has a unit name, but no reg property
Warning (unit_address_vs_reg): Node /fixedregulator@1 has a unit name, but no reg property
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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vcc_3v3_reg and vcc_mmc1_reg are fixed regulators and don't need a reg
property. Remove their unit-address.
Solves:
Warning (unit_address_vs_reg): Node /fixedregulator@0 has a unit name, but no reg property
Warning (unit_address_vs_reg): Node /fixedregulator@1 has a unit name, but no reg property
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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vcc_mmc0_reg is a fixed regulator and doesn't need a reg property. Remove
its unit-address.
Solves:
Warning (unit_address_vs_reg): Node /fixedregulator@0 has a unit name, but no reg property
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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lcd_bus has never been mainlined and is replaced by the atmel_hlcdc driver.
Remove stale nodes.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Endpoint nodes have a reg property. Add their mandatory unit-address.
This solves:
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep0 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep1 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep2 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep3 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep4 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep5 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep6 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep7 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep8 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep9 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep10 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep11 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep12 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep13 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep14 has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): Node /ahb/gadget@00400000/ep15 has a reg or ranges property, but no unit name
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The endpoint nodes have a reg property, they also need a unit-address. Add
them in the example.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The triggers don't need a reg property, remove it when prenset. Also remove
the unit-address from their name.
This solves:
Warning (unit_address_vs_reg): Node /ahb/apb/adc@fc034000/trigger@0 has a unit name, but no reg property
Warning (unit_address_vs_reg): Node /ahb/apb/adc@fc034000/trigger@1 has a unit name, but no reg property
Warning (unit_address_vs_reg): Node /ahb/apb/adc@fc034000/trigger@2 has a unit name, but no reg property
Warning (unit_address_vs_reg): Node /ahb/apb/adc@fc034000/trigger@3 has a unit name, but no reg property
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The trigger doesn't need the reg property. When it is not defined, the node
name doesn't need a unit-address. Remove them from the example.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Due to introducing the new driver - ACT8945A MFD drive,
change the pmic device node to align with the ACT8945A
regulator and charger drivers.
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Add node to support SAMA5D2 Performance Monitor Unit.
Signed-off-by: Olivier Schonken <olivier.schonken@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Add power led node and rename status led node.
Signed-off-by: Raashid Muhammed <raashidmuhammed@zilogic.com>
Reviewed-by: Vijay Kumar B. <vijaykumar@bravegnu.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Add missing pinctrl information to ethernet node.
Signed-off-by: Raashid Muhammed <raashidmuhammed@zilogic.com>
Reviewed-by: Vijay Kumar B. <vijaykumar@bravegnu.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Add Device Tree source file for at91sam9260ek board. This official Atmel
Evaluation Kit is designed around a SoC based on a ARM 926 core the
at91sam9260.
The board is also added to the dts Makefile.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The clocks group properties and the clock@0 node have been obsolete for two
years, remove them.
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The clocks group properties and the clock@0 node have been obsolete for two
years, remove them.
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The clocks group properties and the clock@0 node have been obsolete for two
years, remove them.
Cc: Joachim Eastwood <manabian@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The clocks group properties and the clock@0 node have been obsolete for two
years, remove them.
Cc: Fabio Porcedda <fabio.porcedda@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The clocks group properties and the clock@0 node have been obsolete for two
years, remove them.
Cc: Sergio Tanzilli <tanzilli@acmesystems.it>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The clocks group properties and the clock@0 node have been obsolete for two
years, remove them.
Cc: Rodolfo Giometti <giometti@linux.it>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The clocks group properties and the clock@0 node have been obsolete for two
years, remove them.
Cc: Sergio Tanzilli <tanzilli@acmesystems.it>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The clocks group properties and the clock@0 node have been obsolete for two
years, remove them.
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The Denx MA5D4 dts doesn't properly define the slow_xtal and main_xtal
frequencies, the PMC then has to fallback to using the RC oscillators whose
precision is not really good.
As both crystals are populated, define their frequencies, see p17 of
http://www.denx-cs.de/sites/all/files/MA5D4.HWM_.002.pdf
Also, remove the obsolete main_clock definition.
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Use stdout-path to specify the console and remove the console argument from
the kernel command line.
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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sam9-l9260 is a low cost board designed by Olimex.
More information is available at:
https://www.olimex.com/Products/ARM/Atmel/SAM9-L9260/
Signed-off-by: Raashid Muhammed <raashidmuhammed@zilogic.com>
Reviewed-by: Vijay Kumar B. <vijaykumar@bravegnu.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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Remove leading zeros in OHCI node for at91sam9260 based boards.
Signed-off-by: Raashid Muhammed <raashidmuhammed@zilogic.com>
Reviewed-by: Vijay Kumar B. <vijaykumar@bravegnu.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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The self-test was updated to cover zero-length strings; the function
needs to be updated, too.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Fixes: fcfd2fbf22d2 ("fs/namei.c: Add hashlen_string() function")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The original name was simply hash_string(), but that conflicted with a
function with that name in drivers/base/power/trace.c, and I decided
that calling it "hashlen_" was better anyway.
But you have to do it in two places.
[ This caused build errors for architectures that don't define
CONFIG_DCACHE_WORD_ACCESS - Linus ]
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Fixes: fcfd2fbf22d2 ("fs/namei.c: Add hashlen_string() function")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The HPFS filesystem used generic_show_options to produce string that is
displayed in /proc/mounts. However, there is a problem that the options
may disappear after remount. If we mount the filesystem with option1
and then remount it with option2, /proc/mounts should show both option1
and option2, however it only shows option2 because the whole option
string is replaced with replace_mount_options in hpfs_remount_fs.
To fix this bug, implement the hpfs_show_options function that prints
options that are currently selected.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit c8f33d0bec99 ("affs: kstrdup() memory handling") checks if the
kstrdup function returns NULL due to out-of-memory condition.
However, if we are remounting a filesystem with no change to
filesystem-specific options, the parameter data is NULL. In this case,
kstrdup returns NULL (because it was passed NULL parameter), although no
out of memory condition exists. The mount syscall then fails with
ENOMEM.
This patch fixes the bug. We fail with ENOMEM only if data is non-NULL.
The patch also changes the call to replace_mount_options - if we didn't
pass any filesystem-specific options, we don't call
replace_mount_options (thus we don't erase existing reported options).
Fixes: c8f33d0bec99 ("affs: kstrdup() memory handling")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit ce657611baf9 ("hpfs: kstrdup() out of memory handling") checks if
the kstrdup function returns NULL due to out-of-memory condition.
However, if we are remounting a filesystem with no change to
filesystem-specific options, the parameter data is NULL. In this case,
kstrdup returns NULL (because it was passed NULL parameter), although no
out of memory condition exists. The mount syscall then fails with
ENOMEM.
This patch fixes the bug. We fail with ENOMEM only if data is non-NULL.
The patch also changes the call to replace_mount_options - if we didn't
pass any filesystem-specific options, we don't call
replace_mount_options (thus we don't erase existing reported options).
Fixes: ce657611baf9 ("hpfs: kstrdup() out of memory handling")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Pull more MIPS updates from Ralf Baechle:
"This is the secondnd batch of MIPS patches for 4.7. Summary:
CPS:
- Copy EVA configuration when starting secondary VPs.
EIC:
- Clear Status IPL.
Lasat:
- Fix a few off by one bugs.
lib:
- Mark intrinsics notrace. Not only are the intrinsics
uninteresting, it would cause infinite recursion.
MAINTAINERS:
- Add file patterns for MIPS BRCM device tree bindings.
- Add file patterns for mips device tree bindings.
MT7628:
- Fix MT7628 pinmux typos.
- wled_an pinmux gpio.
- EPHY LEDs pinmux support.
Pistachio:
- Enable KASLR
VDSO:
- Build microMIPS VDSO for microMIPS kernels.
- Fix aliasing warning by building with `-fno-strict-aliasing' for
debugging but also tracing them might result in recursion.
Misc:
- Add missing FROZEN hotplug notifier transitions.
- Fix clk binding example for varioius PIC32 devices.
- Fix cpu interrupt controller node-names in the DT files.
- Fix XPA CPU feature separation.
- Fix write_gc0_* macros when writing zero.
- Add inline asm encoding helpers.
- Add missing VZ accessor microMIPS encodings.
- Fix little endian microMIPS MSA encodings.
- Add 64-bit HTW fields and fix its configuration.
- Fix sigreturn via VDSO on microMIPS kernel.
- Lots of typo fixes.
- Add definitions of SegCtl registers and use them"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (49 commits)
MIPS: Add missing FROZEN hotplug notifier transitions
MIPS: Build microMIPS VDSO for microMIPS kernels
MIPS: Fix sigreturn via VDSO on microMIPS kernel
MIPS: devicetree: fix cpu interrupt controller node-names
MIPS: VDSO: Build with `-fno-strict-aliasing'
MIPS: Pistachio: Enable KASLR
MIPS: lib: Mark intrinsics notrace
MIPS: Fix 64-bit HTW configuration
MIPS: Add 64-bit HTW fields
MAINTAINERS: Add file patterns for mips device tree bindings
MAINTAINERS: Add file patterns for mips brcm device tree bindings
MIPS: Simplify DSP instruction encoding macros
MIPS: Add missing tlbinvf/XPA microMIPS encodings
MIPS: Fix little endian microMIPS MSA encodings
MIPS: Add missing VZ accessor microMIPS encodings
MIPS: Add inline asm encoding helpers
MIPS: Spelling fix lets -> let's
MIPS: VR41xx: Fix typo
MIPS: oprofile: Fix typo
MIPS: math-emu: Fix typo
...
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Various builds (such as i386:allmodconfig) fail with
fs/binfmt_aout.c:133:2: error: expected identifier or '(' before 'return'
fs/binfmt_aout.c:134:1: error: expected identifier or '(' before '}' token
[ Oops. My bad, I had stupidly thought that "allmodconfig" covered this
on x86-64 too, but it obviously doesn't. Egg on my face. - Linus ]
Fixes: 5d22fc25d4fc ("mm: remove more IS_ERR_VALUE abuses")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Pull string hash improvements from George Spelvin:
"This series does several related things:
- Makes the dcache hash (fs/namei.c) useful for general kernel use.
(Thanks to Bruce for noticing the zero-length corner case)
- Converts the string hashes in <linux/sunrpc/svcauth.h> to use the
above.
- Avoids 64-bit multiplies in hash_64() on 32-bit platforms. Two
32-bit multiplies will do well enough.
- Rids the world of the bad hash multipliers in hash_32.
This finishes the job started in commit 689de1d6ca95 ("Minimal
fix-up of bad hashing behavior of hash_64()")
The vast majority of Linux architectures have hardware support for
32x32-bit multiply and so derive no benefit from "simplified"
multipliers.
The few processors that do not (68000, h8/300 and some models of
Microblaze) have arch-specific implementations added. Those
patches are last in the series.
- Overhauls the dcache hash mixing.
The patch in commit 0fed3ac866ea ("namei: Improve hash mixing if
CONFIG_DCACHE_WORD_ACCESS") was an off-the-cuff suggestion.
Replaced with a much more careful design that's simultaneously
faster and better. (My own invention, as there was noting suitable
in the literature I could find. Comments welcome!)
- Modify the hash_name() loop to skip the initial HASH_MIX(). This
would let us salt the hash if we ever wanted to.
- Sort out partial_name_hash().
The hash function is declared as using a long state, even though
it's truncated to 32 bits at the end and the extra internal state
contributes nothing to the result. And some callers do odd things:
- fs/hfs/string.c only allocates 32 bits of state
- fs/hfsplus/unicode.c uses it to hash 16-bit unicode symbols not bytes
- Modify bytemask_from_count to handle inputs of 1..sizeof(long)
rather than 0..sizeof(long)-1. This would simplify users other
than full_name_hash"
Special thanks to Bruce Fields for testing and finding bugs in v1. (I
learned some humbling lessons about "obviously correct" code.)
On the arch-specific front, the m68k assembly has been tested in a
standalone test harness, I've been in contact with the Microblaze
maintainers who mostly don't care, as the hardware multiplier is never
omitted in real-world applications, and I haven't heard anything from
the H8/300 world"
* 'hash' of git://ftp.sciencehorizons.net/linux:
h8300: Add <asm/hash.h>
microblaze: Add <asm/hash.h>
m68k: Add <asm/hash.h>
<linux/hash.h>: Add support for architecture-specific functions
fs/namei.c: Improve dcache hash function
Eliminate bad hash multipliers from hash_32() and hash_64()
Change hash_64() return value to 32 bits
<linux/sunrpc/svcauth.h>: Define hash_str() in terms of hashlen_string()
fs/namei.c: Add hashlen_string() function
Pull out string hash to <linux/stringhash.h>
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This will improve the performance of hash_32() and hash_64(), but due
to complete lack of multi-bit shift instructions on H8, performance will
still be bad in surrounding code.
Designing H8-specific hash algorithms to work around that is a separate
project. (But if the maintainers would like to get in touch...)
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: uclinux-h8-devel@lists.sourceforge.jp
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Microblaze is an FPGA soft core that can be configured various ways.
If it is configured without a multiplier, the standard __hash_32()
will require a call to __mulsi3, which is a slow software loop.
Instead, use a shift-and-add sequence for the constant multiply.
GCC knows how to do this, but it's not as clever as some.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Alistair Francis <alistair.francis@xilinx.com>
Cc: Michal Simek <michal.simek@xilinx.com>
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This provides a multiply by constant GOLDEN_RATIO_32 = 0x61C88647
for the original mc68000, which lacks a 32x32-bit multiply instruction.
Yes, the amount of optimization effort put in is excessive. :-)
Shift-add chain found by Yevgen Voronenko's Hcub algorithm at
http://spiral.ece.cmu.edu/mcm/gen.html
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Philippe De Muyter <phdm@macq.eu>
Cc: linux-m68k@lists.linux-m68k.org
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This is just the infrastructure; there are no users yet.
This is modelled on CONFIG_ARCH_RANDOM; a CONFIG_ symbol declares
the existence of <asm/hash.h>.
That file may define its own versions of various functions, and define
HAVE_* symbols (no CONFIG_ prefix!) to suppress the generic ones.
Included is a self-test (in lib/test_hash.c) that verifies the basics.
It is NOT in general required that the arch-specific functions compute
the same thing as the generic, but if a HAVE_* symbol is defined with
the value 1, then equality is tested.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Philippe De Muyter <phdm@macq.eu>
Cc: linux-m68k@lists.linux-m68k.org
Cc: Alistair Francis <alistai@xilinx.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: uclinux-h8-devel@lists.sourceforge.jp
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Patch 0fed3ac866 improved the hash mixing, but the function is slower
than necessary; there's a 7-instruction dependency chain (10 on x86)
each loop iteration.
Word-at-a-time access is a very tight loop (which is good, because
link_path_walk() is one of the hottest code paths in the entire kernel),
and the hash mixing function must not have a longer latency to avoid
slowing it down.
There do not appear to be any published fast hash functions that:
1) Operate on the input a word at a time, and
2) Don't need to know the length of the input beforehand, and
3) Have a single iterated mixing function, not needing conditional
branches or unrolling to distinguish different loop iterations.
One of the algorithms which comes closest is Yann Collet's xxHash, but
that's two dependent multiplies per word, which is too much.
The key insights in this design are:
1) Barring expensive ops like multiplies, to diffuse one input bit
across 64 bits of hash state takes at least log2(64) = 6 sequentially
dependent instructions. That is more cycles than we'd like.
2) An operation like "hash ^= hash << 13" requires a second temporary
register anyway, and on a 2-operand machine like x86, it's three
instructions.
3) A better use of a second register is to hold a two-word hash state.
With careful design, no temporaries are needed at all, so it doesn't
increase register pressure. And this gets rid of register copying
on 2-operand machines, so the code is smaller and faster.
4) Using two words of state weakens the requirement for one-round mixing;
we now have two rounds of mixing before cancellation is possible.
5) A two-word hash state also allows operations on both halves to be
done in parallel, so on a superscalar processor we get more mixing
in fewer cycles.
I ended up using a mixing function inspired by the ChaCha and Speck
round functions. It is 6 simple instructions and 3 cycles per iteration
(assuming multiply by 9 can be done by an "lea" instruction):
x ^= *input++;
y ^= x; x = ROL(x, K1);
x += y; y = ROL(y, K2);
y *= 9;
Not only is this reversible, two consecutive rounds are reversible:
if you are given the initial and final states, but not the intermediate
state, it is possible to compute both input words. This means that at
least 3 words of input are required to create a collision.
(It also has the property, used by hash_name() to avoid a branch, that
it hashes all-zero to all-zero.)
The rotate constants K1 and K2 were found by experiment. The search took
a sample of random initial states (I used 1023) and considered the effect
of flipping each of the 64 input bits on each of the 128 output bits two
rounds later. Each of the 8192 pairs can be considered a biased coin, and
adding up the Shannon entropy of all of them produces a score.
The best-scoring shifts also did well in other tests (flipping bits in y,
trying 3 or 4 rounds of mixing, flipping all 64*63/2 pairs of input bits),
so the choice was made with the additional constraint that the sum of the
shifts is odd and not too close to the word size.
The final state is then folded into a 32-bit hash value by a less carefully
optimized multiply-based scheme. This also has to be fast, as pathname
components tend to be short (the most common case is one iteration!), but
there's some room for latency, as there is a fair bit of intervening logic
before the hash value is used for anything.
(Performance verified with "bonnie++ -s 0 -n 1536:-2" on tmpfs. I need
a better benchmark; the numbers seem to show a slight dip in performance
between 4.6.0 and this patch, but they're too noisy to quote.)
Special thanks to Bruce fields for diligent testing which uncovered a
nasty fencepost error in an earlier version of this patch.
[checkpatch.pl formatting complaints noted and respectfully disagreed with.]
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Tested-by: J. Bruce Fields <bfields@redhat.com>
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The "simplified" prime multipliers made very bad hash functions, so get rid
of them. This completes the work of 689de1d6ca.
To avoid the inefficiency which was the motivation for the "simplified"
multipliers, hash_64() on 32-bit systems is changed to use a different
algorithm. It makes two calls to hash_32() instead.
drivers/media/usb/dvb-usb-v2/af9015.c uses the old GOLDEN_RATIO_PRIME_32
for some horrible reason, so it inherits a copy of the old definition.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Mauro Carvalho Chehab <m.chehab@samsung.com>
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That's all that's ever asked for, and it makes the return
type of hash_long() consistent.
It also allows (upcoming patch) an optimized implementation
of hash_64 on 32-bit machines.
I tried adding a BUILD_BUG_ON to ensure the number of bits requested
was never more than 32 (most callers use a compile-time constant), but
adding <linux/bug.h> to <linux/hash.h> breaks the tools/perf compiler
unless tools/perf/MANIFEST is updated, and understanding that code base
well enough to update it is too much trouble. I did the rest of an
allyesconfig build with such a check, and nothing tripped.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
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Finally, the first use of previous two patches: eliminate the
separate ad-hoc string hash functions in the sunrpc code.
Now hash_str() is a wrapper around hash_string(), and hash_mem() is
likewise a wrapper around full_name_hash().
Note that sunrpc code *does* call hash_mem() with a zero length, which
is why the previous patch needed to handle that in full_name_hash().
(Thanks, Bruce, for finding that!)
This also eliminates the only caller of hash_long which asks for
more than 32 bits of output.
The comment about the quality of hashlen_string() and full_name_hash()
is jumping the gun by a few patches; they aren't very impressive now,
but will be improved greatly later in the series.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: linux-nfs@vger.kernel.org
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We'd like to make more use of the highly-optimized dcache hash functions
throughout the kernel, rather than have every subsystem create its own,
and a function that hashes basic null-terminated strings is required
for that.
(The name is to emphasize that it returns both hash and length.)
It's actually useful in the dcache itself, specifically d_alloc_name().
Other uses in the next patch.
full_name_hash() is also tweaked to make it more generally useful:
1) Take a "char *" rather than "unsigned char *" argument, to
be consistent with hash_name().
2) Handle zero-length inputs. If we want more callers, we don't want
to make them worry about corner cases.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
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... so they can be used without the rest of <linux/dcache.h>
The hashlen_* macros will make sense next patch.
Signed-off-by: George Spelvin <linux@sciencehorizons.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fix from Wolfram Sang:
"A fix for a regression introduced yesterday.
The regression didn't show up here locally because I did not have
PAGE_POISONING enabled. And buildbots discovered this only after it
hit your tree. Thanks to Dan for the quick response"
* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: dev: use after free in detach
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git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform
Pull chrome platform updates from Olof Johansson
"A handful of Chrome driver and binding changes this merge window:
- a few patches to fix probing and configuration of pstore
- a few patches adding Elan touchpad registration on a few devices
- EC changes: a security fix dealing with max message sizes and
addition of compat_ioctl support.
- keyboard backlight control support
There was also an accidential duplicate registration of trackpads on
'Leon', which was reverted just recently"
* tag 'chrome-platform' of git://git.kernel.org/pub/scm/linux/kernel/git/olof/chrome-platform:
Revert "platform/chrome: chromeos_laptop: Add Leon Touch"
platform/chrome: chromeos_laptop - Add Elan touchpad for Wolf
platform/chrome: chromeos_laptop - Add elan trackpad option for C720
platform/chrome: cros_ec_dev - Populate compat_ioctl
platform/chrome: cros_ec_lightbar - use name instead of ID to hide lightbar attributes
platform/chrome: cros_ec_dev - Fix security issue
platform/chrome: Add Chrome OS keyboard backlight LEDs support
platform/chrome: use to_platform_device()
platform/chrome: pstore: Move to larger record size.
platform/chrome: pstore: probe for ramoops buffer using acpi
platform/chrome: chromeos_laptop: Add Leon Touch
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git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull more sound updates from Takashi Iwai:
"This is the second update round for 4.7-rc1. Most of changes are
about the pending ASoC updates and fixes, including a few new drivers.
Below are some highlights:
ASoC:
- New drivers for MAX98371 and TAS5720
- SPI support for TLV320AIC32x4, along with the module split
- TDM support for STI Uniperf IPs
- Remaining topology API fixes / updates
HDA:
- A couple of Dell quirks and new Realtek codec support"
* tag 'sound-4.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (63 commits)
ALSA: hda - Fix headset mic detection problem for one Dell machine
spi: spi-ep93xx: Fix the PTR_ERR() argument
ALSA: hda/realtek - Add support for ALC295/ALC3254
ASoC: kirkwood: fix build failure
ALSA: hda - Fix headphone noise on Dell XPS 13 9360
ASoC: ak4642: Enable cache usage to fix crashes on resume
ASoC: twl6040: Disconnect AUX output pads on digital mute
ASoC: tlv320aic32x4: Properly implement the positive and negative pins into the mixers
rcar: src: skip disabled-SRC nodes
ASoC: max98371 Remove duplicate entry in max98371_reg
ASoC: twl6040: Select LPPLL during standby
ASoC: rsnd: don't use prohibited number to PDMACHCRn.SRS
ASoC: simple-card: Add pm callbacks to platform driver
ASoC: pxa: Fix module autoload for platform drivers
ASoC: topology: Fix memory leak in widget creation
ASoC: Add max98371 codec driver
ASoC: rsnd: count .probe/.remove for rsnd_mod_call()
ASoC: topology: Check size mismatch of ABI objects before parsing
ASoC: topology: Check failure to create a widget
ASoC: add support for TAS5720 digital amplifier
...
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