tracing: Refactor TRACE_IRQFLAGS_SUPPORT in Kconfig

Make architectures select TRACE_IRQFLAGS_SUPPORT instead of
having many defines.

Link: https://lkml.kernel.org/r/20210731052233.4703-2-masahiroy@

tracing: Refactor TRACE_IRQFLAGS_SUPPORT in Kconfig

Make architectures select TRACE_IRQFLAGS_SUPPORT instead of
having many defines.

Link: https://lkml.kernel.org/r/[email protected]

Acked-by: Heiko Carstens <[email protected]>
Acked-by: Vineet Gupta <[email protected]>   #arch/arc
Acked-by: Michael Ellerman <[email protected]> (powerpc)
Acked-by: Catalin Marinas <[email protected]>
Acked-by: Max Filippov <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

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MIPS: boot: Support specifying UART port on Ingenic SoCs

Allow specifying from the config the UART to use on Ingenic SoCs when
compressed kernel debugging is enabled.

Signed-off-by: Paul Cercueil <

MIPS: boot: Support specifying UART port on Ingenic SoCs

Allow specifying from the config the UART to use on Ingenic SoCs when
compressed kernel debugging is enabled.

Signed-off-by: Paul Cercueil <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

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arch: mips: fix unmet dependency for DEBUG_INFO

When SB1XXX_CORELIS is enabled, COMPILE_TEST is disabled,
and DEBUG_KERNEL is disabled, Kbuild gives the
following warning:

WARNING: unmet direct dep

arch: mips: fix unmet dependency for DEBUG_INFO

When SB1XXX_CORELIS is enabled, COMPILE_TEST is disabled,
and DEBUG_KERNEL is disabled, Kbuild gives the
following warning:

WARNING: unmet direct dependencies detected for DEBUG_INFO
Depends on [n]: DEBUG_KERNEL [=n] && !COMPILE_TEST [=n]
Selected by [y]:
- SB1XXX_CORELIS [=y] && SIBYTE_SB1xxx_SOC [=y] && !COMPILE_TEST [=n]

This is because SB1XXX_CORELIS selects DEBUG_INFO without
selecting or depending on DEBUG_KERNEL, despite DEBUG_INFO
depending on DEBUG_KERNEL.

Signed-off-by: Julian Braha <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

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mips: Add CPS_NS16550_WIDTH config

On some platforms IO-memory might require to use a proper load/store
instructions (like Baikal-T1 IO-memory). To fix the cps-vec UART debug
printout let's add the

mips: Add CPS_NS16550_WIDTH config

On some platforms IO-memory might require to use a proper load/store
instructions (like Baikal-T1 IO-memory). To fix the cps-vec UART debug
printout let's add the CONFIG_CPS_NS16550_WIDTH config to determine which
instructions lb/sb, lh/sh or lw/sw are required for MMIO operations.

Signed-off-by: Serge Semin <[email protected]>
Cc: Alexey Malahov <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Paul Burton <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: [email protected]
Signed-off-by: Thomas Bogendoerfer <[email protected]>

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MIPS: cmdline: Remove redundant Kconfig defaults

CMDLINE, CMDLINE_BOOL & CMDLINE_FORCE all explicitly specify default
values that are the same as the default value for their respective types
anyway

MIPS: cmdline: Remove redundant Kconfig defaults

CMDLINE, CMDLINE_BOOL & CMDLINE_FORCE all explicitly specify default
values that are the same as the default value for their respective types
anyway (ie. n for booleans, and the empty string for strings).

Remove the redundant defaults.

Signed-off-by: Paul Burton <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Cc: [email protected]

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Kconfig: consolidate the "Kernel hacking" menu

Move the source of lib/Kconfig.debug and arch/$(ARCH)/Kconfig.debug to
the top-level Kconfig. For two architectures that means moving their
arch-speci

Kconfig: consolidate the "Kernel hacking" menu

Move the source of lib/Kconfig.debug and arch/$(ARCH)/Kconfig.debug to
the top-level Kconfig. For two architectures that means moving their
arch-specific symbols in that menu into a new arch Kconfig.debug file,
and for a few more creating a dummy file so that we can include it
unconditionally.

Also move the actual 'Kernel hacking' menu to lib/Kconfig.debug, where
it belongs.

Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

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MIPS: Fix CPS SMP NS16550 UART defaults

The MIPS_CPS_NS16550_BASE and MIPS_CPS_NS16550_SHIFT options have no
defaults for non-Malta platforms which select SYS_SUPPORTS_MIPS_CPS
(i.e. the pistachio a

MIPS: Fix CPS SMP NS16550 UART defaults

The MIPS_CPS_NS16550_BASE and MIPS_CPS_NS16550_SHIFT options have no
defaults for non-Malta platforms which select SYS_SUPPORTS_MIPS_CPS
(i.e. the pistachio and generic platforms). This is problematic for
automated allyesconfig and allmodconfig builds based on these platforms,
since make silentoldconfig tries to ask the user for values, and
especially since v4.15 where the default platform was switched to
generic.

Default these options to 0 and arrange for MIPS_CPS_NS16550 to be no
when using that default base address, so that the option only has an
effect when the default is provided (i.e. Malta) or when a value is
provided by the user.

Fixes: 609cf6f2291a ("MIPS: CPS: Early debug using an ns16550-compatible UART")
Signed-off-by: James Hogan <[email protected]>
Reviewed-by: Paul Burton <[email protected]>
Tested-by: Guenter Roeck <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/17749/
Signed-off-by: Ralf Baechle <[email protected]>

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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

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 <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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MIPS: Sibyte: Fix Kconfig warning.

warning: (SB1XXX_CORELIS) selects DEBUG_INFO which has unmet direct dependencies (DEBUG_KERNEL &amp;&amp; !COMPILE_TEST)

Signed-off-by: Ralf Baechle <ralf@linux-m

MIPS: Sibyte: Fix Kconfig warning.

warning: (SB1XXX_CORELIS) selects DEBUG_INFO which has unmet direct dependencies (DEBUG_KERNEL &amp;&amp; !COMPILE_TEST)

Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Remove compact branch policy Kconfig entries

Commit c1a0e9bc885d ("MIPS: Allow compact branch policy to be changed")
added Kconfig entries allowing for the compact branch policy used by the
co

MIPS: Remove compact branch policy Kconfig entries

Commit c1a0e9bc885d ("MIPS: Allow compact branch policy to be changed")
added Kconfig entries allowing for the compact branch policy used by the
compiler for MIPSr6 kernels to be specified. This can be useful for
debugging, particularly in systems where compact branches have recently
been introduced.

Unfortunately mainline gcc 5.x supports MIPSr6 but not the
-mcompact-branches compiler flag, leading to MIPSr6 kernels failing to
build with gcc 5.x with errors such as:

mipsel-linux-gnu-gcc: error: unrecognized command line option '-mcompact-branches=optimal'
make[2]: *** [kernel/bounds.s] Error 1

Fixing this by hiding the Kconfig entry behind another seems to be more
hassle than it's worth, as MIPSr6 & compact branches have been around
for a while now and if policy does need to be set for debug it can be
done easily enough with KCFLAGS. Therefore remove the compact branch
policy Kconfig entries & their handling in the Makefile.

This reverts commit c1a0e9bc885d ("MIPS: Allow compact branch policy to
be changed").

Signed-off-by: Paul Burton <[email protected]>
Reported-by: kbuild test robot <[email protected]>
Fixes: c1a0e9bc885d ("MIPS: Allow compact branch policy to be changed")
Cc: stable <[email protected]> # v4.4+
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/14241/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: CPS: Early debug using an ns16550-compatible UART

Provide support for outputting early debug information, in the form of
various register values should an exception occur, during the early
bri

MIPS: CPS: Early debug using an ns16550-compatible UART

Provide support for outputting early debug information, in the form of
various register values should an exception occur, during the early
bringup of secondary cores. This code requires an ns16550-compatible
UART accessible from the secondary core, and is written in assembly due
to the environment in which such early exceptions occur where way may
not have a stack, be coherent or even have initialised caches.

[[email protected]: Fix merge conflict.]

Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: Steven J. Hill <[email protected]>
Cc: Andrew Bresticker <[email protected]>
Cc: Leonid Yegoshin <[email protected]>
Cc: Maciej W. Rozycki <[email protected]>
Cc: Jason Cooper <[email protected]>
Cc: [email protected]
Cc: James Hogan <[email protected]>
Cc: Markos Chandras <[email protected]>
Patchwork: https://patchwork.linux-mips.org/patch/11202/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Allow L2 prefetch to be configured via debugfs

When debugging or examining the performance of a system it can be useful
to examine the effect of L2 prefetching. Provide an optional debugfs
ent

MIPS: Allow L2 prefetch to be configured via debugfs

When debugging or examining the performance of a system it can be useful
to examine the effect of L2 prefetching. Provide an optional debugfs
entry to allow a user to enable or disable L2 prefetching.

Signed-off-by: Paul Burton <[email protected]>
Cc: Maciej W. Rozycki <[email protected]>
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/11182/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Allow compact branch policy to be changed

When debugging it can be helpful to change the policy for compiler use
of MIPSr6 compact branches, in order to rule out or home in on their
involvemen

MIPS: Allow compact branch policy to be changed

When debugging it can be helpful to change the policy for compiler use
of MIPSr6 compact branches, in order to rule out or home in on their
involvement in bugs. Allow the GCC -mcompact-branches= flag to be set
via Kconfig under the "Kernel hacking" menu.

Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/11178/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Drop CONFIG_RUNTIME_DEBUG & debug.h

The debug.h header provided some MIPS-specific debug macros, which are
no longer used at all. Remove them.

Signed-off-by: Paul Burton <[email protected]

MIPS: Drop CONFIG_RUNTIME_DEBUG & debug.h

The debug.h header provided some MIPS-specific debug macros, which are
no longer used at all. Remove them.

Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/10693/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: kernel: elf: Improve the overall ABI and FPU mode checks

The previous implementation did not cover all possible FPU combinations
and it silently allowed ABI incompatible objects to be loaded w

MIPS: kernel: elf: Improve the overall ABI and FPU mode checks

The previous implementation did not cover all possible FPU combinations
and it silently allowed ABI incompatible objects to be loaded with the
wrong ABI. For example, the previous logic would set the FP_64 ABI as
the matching ABI for an FP_XX object combined with an FP_64A object.
This was wrong, and the matching ABI should have been FP_64A.
The previous logic is now replaced with a new one which determines
the appropriate FPU mode to be used rather than the FP ABI. This has
the advantage that the entire logic is much simpler since it is the FPU
mode we are interested in rather than the FP ABI resulting to code
simplifications. This also removes the now obsolete FP32XX_HYBRID_FPRS
option.

Cc: Matthew Fortune <[email protected]>
Cc: Paul Burton <[email protected]>
Signed-off-by: Markos Chandras <[email protected]>

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MIPS: Kconfig option to better exercise/debug hybrid FPRs

The hybrid FPR scheme exists to allow for compatibility between existing
FP32 code and newly compiled FP64A code. Such code should hopefully

MIPS: Kconfig option to better exercise/debug hybrid FPRs

The hybrid FPR scheme exists to allow for compatibility between existing
FP32 code and newly compiled FP64A code. Such code should hopefully be
rare in the real world, and for the moment is difficult to come across.
All code except that built for the FP64 ABI can correctly execute using
the hybrid FPR scheme, so debugging the hybrid FPR implementation can
be eased by forcing all such code to use it. This is undesirable in
general due to the trap & emulate overhead of the hybrid FPR
implementation, but is a very useful option to have for debugging.

Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: Alexander Viro <[email protected]>
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/7680/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: MT: Remove SMTC support

Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralog

MIPS: MT: Remove SMTC support

Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <[email protected]> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <[email protected]> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.

Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Fix build error due to multiple prom_putchar() definitions.

This can happen if both the generic 8250 and another early console
driver are enable. Fixed by using an auxilliary kconfig symbol t

MIPS: Fix build error due to multiple prom_putchar() definitions.

This can happen if both the generic 8250 and another early console
driver are enable. Fixed by using an auxilliary kconfig symbol to
restrict that choice.

Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Add 8250/16550 serial early printk driver

Signed-off-by: Yoichi Yuasa <[email protected]>
Cc: linux-mips <[email protected]>
Patchwork: https://patchwork.linux-mips.org/patch/947/
S

MIPS: Add 8250/16550 serial early printk driver

Signed-off-by: Yoichi Yuasa <[email protected]>
Cc: linux-mips <[email protected]>
Patchwork: https://patchwork.linux-mips.org/patch/947/
Signed-off-by: Ralf Baechle <[email protected]>

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consolidate per-arch stack overflow debugging options

Original posting:

http://lkml.kernel.org/r/[email protected]

Several architectures have similar stack debugging

consolidate per-arch stack overflow debugging options

Original posting:

http://lkml.kernel.org/r/[email protected]

Several architectures have similar stack debugging config options.
They all pretty much do the same thing, some with slightly
differing help text.

This patch changes the architectures to instead enable a Kconfig
boolean, and then use that boolean in the generic Kconfig.debug
to present the actual menu option. This removes a bunch of
duplication and adds consistency across arches.

Signed-off-by: Dave Hansen <[email protected]>
Reviewed-by: H. Peter Anvin <[email protected]>
Reviewed-by: James Hogan <[email protected]>
Acked-by: Chris Metcalf <[email protected]> [for tile]
Signed-off-by: Dave Hansen <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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Fix typo in various Kconfig file

Correct spelling typo in various Kconfig file.

Signed-off-by: Masanari Iida <[email protected]>
Signed-off-by: Jiri Kosina <[email protected]>

lib: consolidate DEBUG_STACK_USAGE option

Most arches define CONFIG_DEBUG_STACK_USAGE exactly the same way. Move it
to lib/Kconfig.debug so each arch doesn't have to define it. This
obviously make

lib: consolidate DEBUG_STACK_USAGE option

Most arches define CONFIG_DEBUG_STACK_USAGE exactly the same way. Move it
to lib/Kconfig.debug so each arch doesn't have to define it. This
obviously makes the option generic, but that's fine because the config is
already used in generic code.

It's not obvious to me that sysrq-P actually does anything caution by
keeping the most inclusive wording.

Signed-off-by: Stephen Boyd <[email protected]>
Cc: Chris Metcalf <[email protected]>
Acked-by: David S. Miller <[email protected]>
Acked-by: Richard Weinberger <[email protected]>
Acked-by: Mike Frysinger <[email protected]>
Cc: Russell King <[email protected]>
Cc: Hirokazu Takata <[email protected]>
Acked-by: Ralf Baechle <[email protected]>
Cc: Paul Mackerras <[email protected]>
Acked-by: Benjamin Herrenschmidt <[email protected]>
Cc: Chen Liqin <[email protected]>
Cc: Lennox Wu <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT

The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
o

kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT

The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.

This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel. A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).

Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.

Reviewed-by: Ingo Molnar <[email protected]>
Acked-by: David Woodhouse <[email protected]>
Signed-off-by: David Rientjes <[email protected]>
Cc: Greg KH <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Robin Holt <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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MIPS: IRQ: Add stackoverflow detection

Add stackoverflow detection to mips arch

Signed-off-by: Adam Jiang <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: ddaney@c

MIPS: IRQ: Add stackoverflow detection

Add stackoverflow detection to mips arch

Signed-off-by: Adam Jiang <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/1559/
Patchwork: https://patchwork.linux-mips.org/patch/1651/
Signed-off-by: Ralf Baechle <[email protected]>

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MIPS: Crazy spinlock speed test.

This is just a test program for raw_spinlocks. The main reason I
wrote it is to validate my spinlock changes that I sent in a previous
patch.

To use it enable CONF

MIPS: Crazy spinlock speed test.

This is just a test program for raw_spinlocks. The main reason I
wrote it is to validate my spinlock changes that I sent in a previous
patch.

To use it enable CONFIG_DEBUG_FS and CONFIG_SPINLOCK_TEST then at run
time do:

# mount -t debugfs none /sys/kernel/debug/
# cat /sys/kernel/debug/mips/spin_single
# cat /sys/kernel/debug/mips/spin_multi

On my 600MHz octeon cn5860 (16 CPUs) I get

spin_single spin_multi
base 106885 247941
spinlock_patch 75194 219465

This shows that for uncontended locks the spinlock patch gives 41%
improvement and for contended locks 12% improvement (1/time).

Signed-off-by: David Daney <[email protected]>
To: [email protected]
Patchwork: http://patchwork.linux-mips.org/patch/969/
Signed-off-by: Ralf Baechle <[email protected]>

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