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German Gomez 83869019c7 perf arch: Support register names from all archs 
When reading a perf.data file with register values, there is a mismatch
between the names and the values of the registers because the tool is
built using only the register names from the local architecture.

Reading a perf.data file that was recorded on ARM64, gives the following
erroneous output on an X86 machine:

  # perf report -i perf_arm64.data -D
  [...]
  24661932634451 0x698 [0x21d0]: PERF_RECORD_SAMPLE(IP, 0x1): 43239/43239: 0xffffc5be8f100f98 period: 1 addr: 0
  ... user regs: mask 0x1ffffffff ABI 64-bit
  .... AX    0x0000ffffd1515817
  .... BX    0x0000ffffd1515480
  .... CX    0x0000aaaadabf6c80
  .... DX    0x000000000000002e
  .... SI    0x0000000040100401
  .... DI    0x0040600200000080
  .... BP    0x0000ffffd1510e10
  .... SP    0x0000000000000000
  .... IP    0x00000000000000dd
  .... FLAGS 0x0000ffffd1510cd0
  .... CS    0x0000000000000000
  .... SS    0x0000000000000030
  .... DS    0x0000ffffa569a208
  .... ES    0x0000000000000000
  .... FS    0x0000000000000000
  .... GS    0x0000000000000000
  .... R8    0x0000aaaad3de9650
  .... R9    0x0000ffffa57397f0
  .... R10   0x0000000000000001
  .... R11   0x0000ffffa57fd000
  .... R12   0x0000ffffd1515817
  .... R13   0x0000ffffd1515480
  .... R14   0x0000aaaadabf6c80
  .... R15   0x0000000000000000
  .... unknown 0x0000000000000001
  .... unknown 0x0000000000000000
  .... unknown 0x0000000000000000
  .... unknown 0x0000000000000000
  .... unknown 0x0000000000000000
  .... unknown 0x0000ffffd1510d90
  .... unknown 0x0000ffffa5739b90
  .... unknown 0x0000ffffd1510d80
  .... XMM0  0x0000ffffa57392c8
   ... thread: perf-exec:43239
   ...... dso: [kernel.kallsyms]

As can be seen, the register names correspond to X86 registers, even
though the perf.data file was recorded on an ARM64 system. After this
patch, the output of the command displays the correct register names:

  # perf report -i perf_arm64.data -D
  [...]
  24661932634451 0x698 [0x21d0]: PERF_RECORD_SAMPLE(IP, 0x1): 43239/43239: 0xffffc5be8f100f98 period: 1 addr: 0
  ... user regs: mask 0x1ffffffff ABI 64-bit
  .... x0    0x0000ffffd1515817
  .... x1    0x0000ffffd1515480
  .... x2    0x0000aaaadabf6c80
  .... x3    0x000000000000002e
  .... x4    0x0000000040100401
  .... x5    0x0040600200000080
  .... x6    0x0000ffffd1510e10
  .... x7    0x0000000000000000
  .... x8    0x00000000000000dd
  .... x9    0x0000ffffd1510cd0
  .... x10   0x0000000000000000
  .... x11   0x0000000000000030
  .... x12   0x0000ffffa569a208
  .... x13   0x0000000000000000
  .... x14   0x0000000000000000
  .... x15   0x0000000000000000
  .... x16   0x0000aaaad3de9650
  .... x17   0x0000ffffa57397f0
  .... x18   0x0000000000000001
  .... x19   0x0000ffffa57fd000
  .... x20   0x0000ffffd1515817
  .... x21   0x0000ffffd1515480
  .... x22   0x0000aaaadabf6c80
  .... x23   0x0000000000000000
  .... x24   0x0000000000000001
  .... x25   0x0000000000000000
  .... x26   0x0000000000000000
  .... x27   0x0000000000000000
  .... x28   0x0000000000000000
  .... x29   0x0000ffffd1510d90
  .... lr    0x0000ffffa5739b90
  .... sp    0x0000ffffd1510d80
  .... pc    0x0000ffffa57392c8
   ... thread: perf-exec:43239
   ...... dso: [kernel.kallsyms]

Tester comments:

Athira reports:

"Looks good to me. Tested this patchset in powerpc by capturing regs in
powerpc and doing perf report to read the data from x86."

Reported-by: Alexandre Truong <alexandre.truong@arm.com>
Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: German Gomez <german.gomez@arm.com>
Tested-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-csky@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Link: https://lore.kernel.org/r/20211207180653.1147374-4-german.gomez@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-12-16 12:18:12 -03:00
arch s390 updates for 5.16-rc6 2021-12-15 10:52:01 -08:00
block block-5.16-2021-12-10 2021-12-11 09:25:07 -08:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto Update to zstd-1.4.10 2021-11-13 15:32:30 -08:00
Documentation Char/misc driver fixes for 5.16-rc5 2021-12-12 10:16:34 -08:00
drivers hyperv-fixes for 5.16-rc6 2021-12-15 10:46:03 -08:00
fs An SGID directory handling fix (marked for stable), a metrics 2021-12-15 11:06:41 -08:00
include Char/misc driver fixes for 5.16-rc5 2021-12-12 10:16:34 -08:00
init kbuild: Fix -Wimplicit-fallthrough=5 error for GCC 5.x and 6.x 2021-11-14 18:59:49 -08:00
ipc shm: extend forced shm destroy to support objects from several IPC nses 2021-11-20 10:35:54 -08:00
kernel Merge branch 'akpm' (patches from Andrew) 2021-12-11 08:46:52 -08:00
lib Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2021-12-08 16:06:44 -08:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm Merge branch 'for-5.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu 2021-12-11 16:14:17 -08:00
net virtio,vdpa: bugfixes 2021-12-13 14:34:22 -08:00
samples ftrace/samples: Add module to test multi direct modify interface 2021-12-09 13:02:44 -05:00
scripts recordmcount.pl: look for jgnop instruction as well as bcrl on s390 2021-12-12 18:52:26 +01:00
security selinux: fix NULL-pointer dereference when hashtab allocation fails 2021-11-19 16:11:39 -05:00
sound sound fixes for 5.16-rc5 2021-12-10 11:43:00 -08:00
tools perf arch: Support register names from all archs 2021-12-16 12:18:12 -03:00
usr initramfs: Check timestamp to prevent broken cpio archive 2021-10-24 13:48:40 +09:00
virt KVM: downgrade two BUG_ONs to WARN_ON_ONCE 2021-11-26 06:43:28 -05:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: update email address for Guo Ren 2021-12-10 17:10:55 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Char/misc driver fixes for 5.16-rc5 2021-12-12 10:16:34 -08:00
Makefile Linux 5.16-rc5 2021-12-12 14:53:01 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.