mips: kernel: use DEFINE_DEBUGFS_ATTRIBUTE with debugfs_create_file_unsafe()

debugfs_create_file_unsafe does not protect the fops handed to it
against file removal. DEFINE_DEBUGFS_ATTRIBUTE makes th

mips: kernel: use DEFINE_DEBUGFS_ATTRIBUTE with debugfs_create_file_unsafe()

debugfs_create_file_unsafe does not protect the fops handed to it
against file removal. DEFINE_DEBUGFS_ATTRIBUTE makes the fops aware of
the file lifetime and thus protects it against removal.

Signed-off-by: Wang Qing <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

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mips: kernel: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code l

mips: kernel: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

Cc: Ralf Baechle <[email protected]>
Cc: Paul Burton <[email protected]>
Cc: James Hogan <[email protected]>
Cc: Yangtao Li <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Mathieu Malaterre <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Marcin Nowakowski <[email protected]>
Cc: Yasha Cherikovsky <[email protected]>
Cc: [email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Paul Burton <[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: Declare mips_debugfs_dir in a header

We have many extern declarations of mips_debugfs_dir through arch/mips/
in various C files. Unify them by declaring mips_debugfs_dir in a
header, including

MIPS: Declare mips_debugfs_dir in a header

We have many extern declarations of mips_debugfs_dir through arch/mips/
in various C files. Unify them by declaring mips_debugfs_dir in a
header, including it in each affected C file & removing the duplicate
declarations.

Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: Steven J. Hill <[email protected]>
Cc: Alexander Sverdlin <[email protected]>
Cc: Masahiro Yamada <[email protected]>
Cc: Leonid Yegoshin <[email protected]>
Cc: Maciej W. Rozycki <[email protected]>
Cc: [email protected]
Cc: Joe Perches <[email protected]>
Cc: Jaedon Shin <[email protected]>
Cc: James Hogan <[email protected]>
Cc: David Daney <[email protected]>
Cc: Zubair Lutfullah Kakakhel <[email protected]>
Cc: Markos Chandras <[email protected]>
Cc: James Cowgill <[email protected]>
Patchwork: https://patchwork.linux-mips.org/patch/11181/
Signed-off-by: Ralf Baechle <[email protected]>

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mips: migrate core kernel file from module.h --> export.h

These files are not modules, but were including module.h only for
EXPORT_SYMBOL and/or THIS_MODULE. Now that we have the lightweight
export

mips: migrate core kernel file from module.h --> export.h

These files are not modules, but were including module.h only for
EXPORT_SYMBOL and/or THIS_MODULE. Now that we have the lightweight
export.h, use it in these kinds of cases.

Signed-off-by: Paul Gortmaker <[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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