1. 21 May, 2018 6 commits
  2. 27 Mar, 2018 2 commits
    • Alexander Monakov's avatar
      drivers/perf: arm_pmu_platform: do not warn about affinity on uniprocessor · 65bd053f
      Alexander Monakov authored
      If there is exactly one CPU present, there is no ambiguity: do not warn
      that PMU setup would need to guess IRQ affinity.
      
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Signed-off-by: Alexander Monakov's avatarAlexander Monakov <amonakov@ispras.ru>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      65bd053f
    • Arnd Bergmann's avatar
      perf: arm_spe: include linux/vmalloc.h for vmap() · fcd9f831
      Arnd Bergmann authored
      On linux-next, I get a build failure in some configurations:
      
      drivers/perf/arm_spe_pmu.c: In function 'arm_spe_pmu_setup_aux':
      drivers/perf/arm_spe_pmu.c:857:14: error: implicit declaration of function 'vmap'; did you mean 'swap'? [-Werror=implicit-function-declaration]
        buf->base = vmap(pglist, nr_pages, VM_MAP, PAGE_KERNEL);
                    ^~~~
                    swap
      drivers/perf/arm_spe_pmu.c:857:37: error: 'VM_MAP' undeclared (first use in this function); did you mean 'VM_MPX'?
        buf->base = vmap(pglist, nr_pages, VM_MAP, PAGE_KERNEL);
                                           ^~~~~~
                                           VM_MPX
      drivers/perf/arm_spe_pmu.c:857:37: note: each undeclared identifier is reported only once for each function it appears in
      drivers/perf/arm_spe_pmu.c: In function 'arm_spe_pmu_free_aux':
      drivers/perf/arm_spe_pmu.c:878:2: error: implicit declaration of function 'vunmap'; did you mean 'iounmap'? [-Werror=implicit-function-declaration]
      
      vmap() is declared in linux/vmalloc.h, so we should include that header file.
      Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      [will: add additional missing #includes reported by Mark]
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      fcd9f831
  3. 16 Mar, 2018 2 commits
  4. 12 Mar, 2018 1 commit
    • Peter Zijlstra's avatar
      perf/core: Remove perf_event::group_entry · 8343aae6
      Peter Zijlstra authored
      Now that all the grouping is done with RB trees, we no longer need
      group_entry and can replace the whole thing with sibling_list.
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: David Carrillo-Cisneros <davidcc@google.com>
      Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Kan Liang <kan.liang@intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Stephane Eranian <eranian@google.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
      Cc: Vince Weaver <vincent.weaver@maine.edu>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      8343aae6
  5. 06 Mar, 2018 5 commits
  6. 28 Feb, 2018 1 commit
    • Will Deacon's avatar
      arm_pmu: Use disable_irq_nosync when disabling SPI in CPU teardown hook · b08e5fd9
      Will Deacon authored
      Commit 6de3f791 ("arm_pmu: explicitly enable/disable SPIs at hotplug")
      moved all of the arm_pmu IRQ enable/disable calls to the CPU hotplug hooks,
      regardless of whether they are implemented as PPIs or SPIs. This can
      lead to us sleeping from atomic context due to disable_irq blocking:
      
       | BUG: sleeping function called from invalid context at kernel/irq/manage.c:112
       | in_atomic(): 1, irqs_disabled(): 128, pid: 15, name: migration/1
       | no locks held by migration/1/15.
       | irq event stamp: 192
       | hardirqs last  enabled at (191): [<00000000803c2507>]
       | _raw_spin_unlock_irq+0x2c/0x4c
       | hardirqs last disabled at (192): [<000000007f57ad28>] multi_cpu_stop+0x9c/0x140
       | softirqs last  enabled at (0): [<0000000004ee1b58>]
       | copy_process.isra.77.part.78+0x43c/0x1504
       | softirqs last disabled at (0): [<          (null)>]           (null)
       | CPU: 1 PID: 15 Comm: migration/1 Not tainted 4.16.0-rc3-salvator-x #1651
       | Hardware name: Renesas Salvator-X board based on r8a7796 (DT)
       | Call trace:
       |  dump_backtrace+0x0/0x140
       |  show_stack+0x14/0x1c
       |  dump_stack+0xb4/0xf0
       |  ___might_sleep+0x1fc/0x218
       |  __might_sleep+0x70/0x80
       |  synchronize_irq+0x40/0xa8
       |  disable_irq+0x20/0x2c
       |  arm_perf_teardown_cpu+0x80/0xac
      
      Since the interrupt is always CPU-affine and this code is running with
      interrupts disabled, we can just use disable_irq_nosync as we know there
      isn't a concurrent invocation of the handler to worry about.
      
      Fixes: 6de3f791 ("arm_pmu: explicitly enable/disable SPIs at hotplug")
      Reported-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Tested-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
      Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      b08e5fd9
  7. 20 Feb, 2018 7 commits
  8. 07 Feb, 2018 1 commit
  9. 15 Jan, 2018 1 commit
  10. 02 Jan, 2018 2 commits
  11. 11 Dec, 2017 1 commit
  12. 03 Nov, 2017 1 commit
  13. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      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: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  14. 24 Oct, 2017 1 commit
  15. 19 Oct, 2017 4 commits
  16. 18 Oct, 2017 1 commit
    • Will Deacon's avatar
      drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension · d5d9696b
      Will Deacon authored
      The ARMv8.2 architecture introduces the optional Statistical Profiling
      Extension (SPE).
      
      SPE can be used to profile a population of operations in the CPU pipeline
      after instruction decode. These are either architected instructions (i.e.
      a dynamic instruction trace) or CPU-specific uops and the choice is fixed
      statically in the hardware and advertised to userspace via caps/. Sampling
      is controlled using a sampling interval, similar to a regular PMU counter,
      but also with an optional random perturbation to avoid falling into patterns
      where you continuously profile the same instruction in a hot loop.
      
      After each operation is decoded, the interval counter is decremented. When
      it hits zero, an operation is chosen for profiling and tracked within the
      pipeline until it retires. Along the way, information such as TLB lookups,
      cache misses, time spent to issue etc is captured in the form of a sample.
      The sample is then filtered according to certain criteria (e.g. load
      latency) that can be specified in the event config (described under
      format/) and, if the sample satisfies the filter, it is written out to
      memory as a record, otherwise it is discarded. Only one operation can
      be sampled at a time.
      
      The in-memory buffer is linear and virtually addressed, raising an
      interrupt when it fills up. The PMU driver handles these interrupts to
      give the appearance of a ring buffer, as expected by the AUX code.
      
      The in-memory trace-like format is self-describing (though not parseable
      in reverse) and written as a series of records, with each record
      corresponding to a sample and consisting of a sequence of packets. These
      packets are defined by the architecture, although some have CPU-specific
      fields for recording information specific to the microarchitecture.
      
      As a simple example, a record generated for a branch instruction may
      consist of the following packets:
      
        0 (Address) : Virtual PC of the branch instruction
        1 (Type)    : Conditional direct branch
        2 (Counter) : Number of cycles taken from Dispatch to Issue
        3 (Address) : Virtual branch target + condition flags
        4 (Counter) : Number of cycles taken from Dispatch to Complete
        5 (Events)  : Mispredicted as not-taken
        6 (END)     : End of record
      
      It is also possible to toggle properties such as timestamp packets in
      each record.
      
      This patch adds support for SPE in the form of a new perf driver.
      
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Reviewed-by: default avatarMark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      d5d9696b
  17. 04 Oct, 2017 1 commit
  18. 02 Oct, 2017 1 commit
  19. 22 Sep, 2017 1 commit