Changes in atomic-gcc.h

bb056c0f - tools: KVM: selftests: Convert clear/set_bit() to actual atomics

Sat, 19 Nov 2022 01:34:50 +0000

tools: KVM: selftests: Convert clear/set_bit() to actual atomicsConvert {clear,set}_bit() to atomics as KVM's ucall implementation relieson clear_bit() being atomic, they are defined in atomic.h, and the samehelpers in the kernel proper are atomic.KVM's ucall infrastructure is the only user of clear_bit() in tools/, andthere are no true set_bit() users. tools/testing/nvdimm/ does make heavyuse of set_bit(), but that code builds into a kernel module of sorts, i.e.pulls in all of the kernel's header and so is already getting the kernel'satomic set_bit().Signed-off-by: Sean Christopherson Message-Id: <20221119013450.2643007-10-seanjc@google.com>Signed-off-by: Paolo Bonzini List of files: /linux-6.15/tools/include/asm-generic/atomic-gcc.h

36293352 - tools: Drop "atomic_" prefix from atomic test_and_set_bit()

Sat, 19 Nov 2022 01:34:49 +0000

tools: Drop "atomic_" prefix from atomic test_and_set_bit()Drop the "atomic_" prefix from tools' atomic_test_and_set_bit() tomatch the kernel nomenclature where test_and_set_bit() is atomic,and __test_and_set_bit() provides the non-atomic variant.Signed-off-by: Sean Christopherson Message-Id: <20221119013450.2643007-9-seanjc@google.com>Signed-off-by: Paolo Bonzini List of files: /linux-6.15/tools/include/asm-generic/atomic-gcc.h

cf4694be - tools: Add atomic_test_and_set_bit()

Thu, 06 Oct 2022 00:34:06 +0000

tools: Add atomic_test_and_set_bit()Add x86 and generic implementations of atomic_test_and_set_bit() to allowKVM selftests to atomically manage bitmaps.Note, the generic version is taken from arch_test_and_set_bit() as ofcommit 415d83249709 ("locking/atomic: Make test_and_*_bit() ordered onfailure").Signed-off-by: Peter Gonda Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson Link: https://lore.kernel.org/r/20221006003409.649993-5-seanjc@google.com List of files: /linux-6.15/tools/include/asm-generic/atomic-gcc.h

b2441318 - License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Wed, 01 Nov 2017 14:07:57 +0000

License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseMany source files in the tree are missing licensing information, whichmakes it harder for compliance tools to determine the correct license.By default all files without license information are under the defaultlicense 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 bindingshorthand, which can be used instead of the full boiler plate text.This patch is based on work done by Thomas Gleixner and Kate Stewart andPhilippe Ombredanne.How this work was done:Patches were generated and checked against linux-4.14-rc6 for a subset ofthe 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 caseswhere non-standard license headers were used, and references to licensehad to be inferred by heuristics based on keywords.The analysis to determine which SPDX License Identifier to be applied toa file was done in a spreadsheet of side by side results from of theoutput of two independent scanners (ScanCode & Windriver) producing SPDXtag:value files created by Philippe Ombredanne. Philippe prepared thebase 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 filesassessed. Kate Stewart did a file by file comparison of the scannerresults in the spreadsheet to determine which SPDX license identifier(s)to be applied to the file. She confirmed any determination that was notimmediately 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 licenseidentifiers 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 thespreadsheet to determine the SPDX license identifiers to apply to thesource files by Kate, Philippe, Thomas and, in some cases, confirmationby lawyers working with the Linux Foundation.Kate also obtained a third independent scan of the 4.13 code base fromFOSSology, and compared selected files where the other two scannersdisagreed against that SPDX file, to see if there was new insights. TheWindriver scanner is based on an older version of FOSSology in part, sothey are related.Thomas did random spot checks in about 500 files from the spreadsheetsfor the uapi headers and agreed with SPDX license identifier in thefiles he inspected. For the non-uapi files Thomas did random spot checksin about 15000 files.In initial set of patches against 4.14-rc6, 3 files were found to havecopy/paste license identifier errors, and have been fixed to reflect thecorrect identifier.Additionally Philippe spent 10 hours this week doing a detailed manualinspection and review of the 12,461 patched files from the initial patchversion 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 correctThis produced a worksheet with 20 files needing minor correction. Thisworksheet was then exported into 3 different .csv files for thedifferent types of files to be modified.These .csv files were then reviewed by Greg. Thomas wrote a script toparse the csv files and add the proper SPDX tag to the file, in theformat that the file expected. This script was further refined by Gregbased on the output to detect more types of files automatically and todistinguish between header and source .c files (which need differentcomment types.) Finally Greg ran the script using the .csv files togenerate the patches.Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman List of files: /linux-6.15/tools/include/asm-generic/atomic-gcc.h

6aa7de05 - locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()

Mon, 23 Oct 2017 21:07:29 +0000

locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()Please do not apply this to mainline directly, instead please re-run thecoccinelle script shown below and apply its output.For several reasons, it is desirable to use {READ,WRITE}_ONCE() inpreference to ACCESS_ONCE(), and new code is expected to use one of theformer. So far, there's been no reason to change most existing uses ofACCESS_ONCE(), as these aren't harmful, and changing them results inchurn.However, for some features, the read/write distinction is critical tocorrect operation. To distinguish these cases, separate read/writeaccessors must be used. This patch migrates (most) remainingACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the followingcoccinelle script:----// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and// WRITE_ONCE()// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patchvirtual patch@ depends on patch @expression E1, E2;@@- ACCESS_ONCE(E1) = E2+ WRITE_ONCE(E1, E2)@ depends on patch @expression E;@@- ACCESS_ONCE(E)+ READ_ONCE(E)----Signed-off-by: Mark Rutland Signed-off-by: Paul E. McKenney Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: davem@davemloft.netCc: linux-arch@vger.kernel.orgCc: mpe@ellerman.id.auCc: shuah@kernel.orgCc: snitzer@redhat.comCc: thor.thayer@linux.intel.comCc: tj@kernel.orgCc: viro@zeniv.linux.org.ukCc: will.deacon@arm.comLink: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.comSigned-off-by: Ingo Molnar List of files: /linux-6.15/tools/include/asm-generic/atomic-gcc.h

ed4aad50 - tools include: Provide gcc based cmpxchg fallback for !x86

Thu, 23 Feb 2017 18:33:02 +0000

tools include: Provide gcc based cmpxchg fallback for !x86We've been using an atomic_t implementation subset based on the gccbuiltin functions for a while, now, with refcount.h we need cmpxchg(),use gcc's __sync_val_compare_and_swap() for that.Cc: Adrian Hunter Cc: David Ahern Cc: Elena Reshetova Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-b9zovyxgpa0c4vi3nm0kjo97@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo List of files: /linux-6.15/tools/include/asm-generic/atomic-gcc.h

da6d8567 - tools include: Add basic atomic.h implementation from the kernel sources

Tue, 07 Apr 2015 14:53:41 +0000

tools include: Add basic atomic.h implementation from the kernel sourcesUses the arch/x86/ kernel code for x86_64/i386, fallbacking to a gccintrinsics implementation that has been tested in at least sparc64.Will be used for reference counting in tools/perf.Acked-by: David Ahern Cc: Adrian Hunter Cc: Borislav Petkov Cc: Don Zickus Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-knfpjowhgyh6x4z0kfuk389j@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo List of files: /linux-6.15/tools/include/asm-generic/atomic-gcc.h