kernel.git/arch/arm/kernel/perf_event_v7.c, branch linux-4.17.y

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

arm: perf: use builtin_platform_driver

2017-02-03T18:46:42Z

Use builtin_platform_driver() helper to simplify the code. Signed-off-by: Geliang Tang Signed-off-by: Will Deacon

arm: perf: move to common attr_group fields

2016-09-09T13:51:51Z

By using a common attr_groups array, the common arm_pmu code can set up common files (e.g. cpumask) for us in subsequent patches. Signed-off-by: Mark Rutland Cc: Will Deacon Signed-off-by: Will Deacon

ARM: perf: Set ARMv7 SDER SUNIDEN bit

2016-01-25T18:37:44Z

ARMv7 counters other than the CPU cycle counter only work if the Secure Debug Enable Register (SDER) SUNIDEN bit is set. Since access to the SDER is only possible in secure state, it will only be done if the device tree property "secure-reg-access" is set. Without this: Performance counter stats for 'sleep 1': 14606094 cycles # 0.000 GHz 0 instructions # 0.00 insns per cycle After applying: Performance counter stats for 'sleep 1': 5843809 cycles 2566484 instructions # 0.44 insns per cycle 1.020144000 seconds time elapsed Some platforms (eg i.MX53) may also need additional platform specific setup. Acked-by: Rob Herring Signed-off-by: Martin Fuzzey Signed-off-by: Pooya Keshavarzi Signed-off-by: George G. Davis [will: add warning if property is found on arm64] Signed-off-by: Will Deacon

ARM: perf: add format entry to describe event -> config mapping

2015-12-22T14:42:57Z

It's all very well providing an events directory to userspace that details our events in terms of "event=0xNN", but if we don't define how to encode the "event" field in the perf attr.config, then it's a waste of time. This patch adds a single format entry to describe that the event field occupies the bottom 8 bits of our config field on ARMv7. Signed-off-by: Will Deacon

arm: perf: Add event descriptions

2015-11-16T15:41:49Z

Add additional information about the ARM architected hardware events to make counters self describing. This makes the hardware PMUs easier to use as perf list contains possible events instead of users having to refer to documentation like the ARM TRMs. Signed-off-by: Drew Richardson Signed-off-by: Will Deacon

arm: perf: Convert event enums to #defines

2015-11-16T15:41:49Z

The enums are not necessary and this allows the event values to be used to construct static strings at compile time. Signed-off-by: Drew Richardson Signed-off-by: Will Deacon

arm: perf: factor arm_pmu core out to drivers

2015-07-31T14:01:14Z

To enable sharing of the arm_pmu code with arm64, this patch factors it out to drivers/perf/. A new drivers/perf directory is added for performance monitor drivers to live under. MAINTAINERS is updated accordingly. Files added previously without a corresponsing MAINTAINERS update (perf_regs.c, perf_callchain.c, and perf_event.h) are also added. Cc: Arnaldo Carvalho de Melo Cc: Greg Kroah-Hartman Cc: Ingo Molnar Cc: Linus Walleij Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Russell King Cc: Will Deacon Signed-off-by: Mark Rutland [will: augmented Kconfig help slightly] Signed-off-by: Will Deacon

arm: perf: factor out armv7 pmu driver

2015-05-28T15:54:18Z

Now that the core arm perf code maintains no global state and all microarchitecture-specific PMU data can be fed in through the shared probe function, it's possible to use it as a library and get rid of the C file includes we have currently. This patch factors out the ARMv7-specific portions out into the ARMv7 driver. For the moment this is always built if perf event support is enabled, but the preprocessor guards will leave behind an empty file. Now that perf_event_cpu.c contains no microarchitecture-specific data, the associated probing code is removed, completing its relegation to a library file. The vestigal "arm-pmu" platform device ID is removed in this patch, as it has been unused since platform files were updated to specify a more specific PMU variant. Signed-off-by: Mark Rutland Signed-off-by: Will Deacon

arm: perf: probe number of counters on affine CPUs

2015-05-27T15:12:36Z

In heterogeneous systems, the number of counters may differ across clusters. To find the number of counters for a cluster, we must probe the PMU from a CPU in that cluster. Reviewed-by: Will Deacon Signed-off-by: Mark Rutland Signed-off-by: Will Deacon