Commit Graph

18 Commits

Author SHA1 Message Date
Martin Schwidefsky
9fa1db4c75 s390: add a few more SPDX identifiers
Add the correct SPDX license to a few more files under arch/s390 and
drivers/s390 which have been missed to far.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-12-05 07:51:09 +01:00
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
Heiko Carstens
e6d4a636ac s390/numa: pin all possible cpus to nodes early
It is required to have an early static cpu to node mapping. This patch
pins all possible cpus to nodes for which no topology information is
present. Since there is no interface available which would allow to
tell where a non-present cpu would appear topology-wise, simply use a
round robin algorithm.
Right now this makes sure that the cpu_to_node() function will return
the same value for a cpu during the life time of the system.

Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-07 07:23:33 +01:00
Heiko Carstens
8c91058022 s390/numa: establish cpu to node mapping early
Initialize the cpu topology and therefore also the cpu to node mapping
much earlier. Fixes this warning and subsequent crashes when using the
fake numa emulation mode on s390:

WARNING: CPU: 0 PID: 1 at include/linux/cpumask.h:121 select_task_rq+0xe6/0x1a8
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0-rc6-00001-ge9d867a67fd0-dirty #28
task: 00000001dd270008 ti: 00000001eccb4000 task.ti: 00000001eccb4000
Krnl PSW : 0404c00180000000 0000000000176c56 (select_task_rq+0xe6/0x1a8)
           R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3
Call Trace:
([<0000000000176c30>] select_task_rq+0xc0/0x1a8)
([<0000000000177d64>] try_to_wake_up+0x2e4/0x478)
([<000000000015d46c>] create_worker+0x174/0x1c0)
([<0000000000161a98>] alloc_unbound_pwq+0x360/0x438)
([<0000000000162550>] apply_wqattrs_prepare+0x200/0x2a0)
([<000000000016266a>] apply_workqueue_attrs_locked+0x7a/0xb0)
([<0000000000162af0>] apply_workqueue_attrs+0x50/0x78)
([<000000000016441c>] __alloc_workqueue_key+0x304/0x520)
([<0000000000ee3706>] default_bdi_init+0x3e/0x70)
([<0000000000100270>] do_one_initcall+0x140/0x1d8)
([<0000000000ec9da8>] kernel_init_freeable+0x220/0x2d8)
([<0000000000984a7a>] kernel_init+0x2a/0x150)
([<00000000009913fa>] kernel_thread_starter+0x6/0xc)
([<00000000009913f4>] kernel_thread_starter+0x0/0xc)

Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-07 07:23:25 +01:00
Heiko Carstens
30fc4ca2a8 s390/topology: use cpu_topology array instead of per cpu variable
CPU topology information like cpu to node mapping must be setup in
setup_arch already. Topology information is currently made available
with a per cpu variable; this however will not work when the
initialization will be moved to setup_arch, since the generic percpu
setup will be done much later.

Therefore convert back to a cpu_topology array.

Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-07 07:23:16 +01:00
Heiko Carstens
307b3114ef s390/numa: always use logical cpu and core ids
The toptree algorithm uses the physical core ids to create a mapping
between cores and nodes (to_node_id array within emu_cores structure).
The core ids are used as an index into an array which size depends on
CONFIG_NR_CPUS. If the physical core ids are larger, this will result
in out-of-bounds write accesses.

Generate logical core ids instead to avoid this.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-07 07:22:41 +01:00
Heiko Carstens
ef4423ce70 s390/numa: only set possible nodes within node_possible_map
Make sure that only those nodes appear in the node_possible_map that
may actually be used. Usually that means that the node online and
possible maps are identical. For mode "plain" we only have one node,
for mode "emu" we have "emu_nodes" nodes.

Before this the possible map included (with default config) 16 nodes
while usually only one was used. That made a couple of loops that
iterated over all possible nodes do more work than necessary.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-07-31 05:28:00 -04:00
Heiko Carstens
adac0f1e8c s390/topology: add drawer scheduling domain level
The z13 machine added a fourth level to the cpu topology
information. The new top level is called drawer.

A drawer contains two books, which used to be the top level.

Adding this additional scheduling domain did show performance
improvements for some workloads of up to 8%, while there don't
seem to be any workloads impacted in a negative way.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13 15:58:27 +02:00
Michael Holzheu
2d0f76a6ca s390/numa: move numa_init_late() from device to arch_initcall
Commit 3e89e1c5ea ("hugetlb: make mm and fs code explicitly non-modular")
moves hugetlb_init() from module_init to subsys_initcall.

The hugetlb_init()->hugetlb_register_node() code accesses "node->dev.kobj"
which is initialized in numa_init_late().

Since numa_init_late() is a device_initcall which is called *after*
subsys_initcall the above mentioned patch breaks NUMA on s390.

So fix this and move numa_init_late() to arch_initcall.

Fixes: 3e89e1c5ea ("hugetlb: make mm and fs code explicitly non-modular")
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-26 12:45:24 +01:00
Heiko Carstens
cd17e153af s390: remove superfluous memblock_alloc() return value checks
memblock_alloc() and memblock_alloc_base() will panic on their own if
they can't find free memory. Therefore remove some pointless checks.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-19 12:14:02 +01:00
Heiko Carstens
ef1f7fd7eb s390/numa: allocate memory with correct alignment
Allocating memory with a requested minimum alignment of 1 is wrong
since pg_data_t contains a spinlock which requires an alignment of 4
bytes.

Therefore fix this and ask for an alignment of 8 bytes like it is
guarenteed for all kmalloc requests.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-19 12:14:01 +01:00
Michael Holzheu
b02064a9b8 s390/numa: write kernel message when emu_size has been increased
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:31:59 +02:00
Martin Schwidefsky
22be9cd9f2 s390/numa: use correct type for node_to_cpumask_map
With CONFIG_CPUMASK_OFFSTACK=y cpumask_var_t is a pointer to a CPU mask.
Replace the incorrect type for node_to_cpumask_map with cpumask_t.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-23 09:18:56 +02:00
Michael Holzheu
7cde4910a5 s390/numa: make core to node mapping data dynamic
The core to node mapping data consumes about 2 KB bss data. To save memory
for the non-NUMA case, make the data dynamic. In addition change the
"core_to_node" array from "int" to "s32" which saves 1 KB also for the
NUMA case.

Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-07 09:57:38 +02:00
Michael Holzheu
3a3814c28b s390/topology: remove topology lock
Since we are already protected by the "sched_domains_mutex" lock, we can
safely remove the topology lock.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-07 09:56:58 +02:00
Michael Holzheu
c29a7baf09 s390/numa: add emulation support
NUMA emulation (aka fake NUMA) distributes the available memory to nodes
without using real topology information about the physical memory of the
machine.

Splitting the system memory into nodes replicates the memory management
structures for each node. Particularly each node has its own "mm locks"
and its own "kswapd" task.

For large systems, under certain conditions, this results in improved
system performance and/or latency based on reduced pressure on the mm
locks and the kswapd tasks.

NUMA emulation distributes CPUs to nodes while respecting the original
machine topology information. This is done by trying to avoid to separate
CPUs which reside on the same book or even on the same MC. Because the
current Linux scheduler code requires a stable cpu to node mapping, cores
are pinned to nodes when the first CPU thread is set online.

This patch is based on the initial implementation from Philipp Hachtmann.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-04 14:06:53 +02:00
Philipp Hachtmann
e8054b654b s390/numa: add topology tree infrastructure
NUMA emulation needs proper means to mangle the book/mc/core topology
of the machine. The topology tree (toptree) consistently maintains cpu
masks for the root, each node, and all leaves of the tree while the
user may use the toptree functions to rearrange the tree in various
ways.

This patch contains several changes from Michael Holzheu.

Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-03 18:40:26 +02:00
Philipp Hachtmann
3a368f742d s390/numa: add core infrastructure
Enable core NUMA support for s390 and add one simple default mode "plain"
that creates one single NUMA node.

This patch contains several changes from Michael Holzheu.

Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-08-03 18:40:25 +02:00