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  1. 24 9月, 2018 1 次提交
  3. 23 5月, 2018 8 次提交
  5. 28 4月, 2018 1 次提交
  7. 27 4月, 2018 7 次提交
  9. 02 11月, 2017 1 次提交
    • G
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      由 Greg Kroah-Hartman 提交于 
      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: NKate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: NPhilippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  11. 29 9月, 2017 1 次提交
  13. 29 8月, 2017 1 次提交
    • L
      perf symbols: Fix plt entry calculation for ARM and AARCH64 · b2f76050
      由 Li Bin 提交于 
      On x86, the plt header size is as same as the plt entry size, and can be
identified from shdr's sh_entsize of the plt.

But we can't assume that the sh_entsize of the plt shdr is always the
plt entry size in all architecture, and the plt header size may be not
as same as the plt entry size in some architecure.

On ARM, the plt header size is 20 bytes and the plt entry size is 12
bytes (don't consider the FOUR_WORD_PLT case) that refer to the binutils
implementation. The plt section is as follows:

Disassembly of section .plt:
000004a0 <__cxa_finalize@plt-0x14>:
 4a0:   e52de004        push    {lr}            ; (str lr, [sp, #-4]!)
 4a4:   e59fe004        ldr     lr, [pc, #4]    ; 4b0 <_init+0x1c>
 4a8:   e08fe00e        add     lr, pc, lr
 4ac:   e5bef008        ldr     pc, [lr, #8]!
 4b0:   00008424        .word   0x00008424

000004b4 <__cxa_finalize@plt>:
 4b4:   e28fc600        add     ip, pc, #0, 12
 4b8:   e28cca08        add     ip, ip, #8, 20  ; 0x8000
 4bc:   e5bcf424        ldr     pc, [ip, #1060]!        ; 0x424

000004c0 <printf@plt>:
 4c0:   e28fc600        add     ip, pc, #0, 12
 4c4:   e28cca08        add     ip, ip, #8, 20  ; 0x8000
 4c8:   e5bcf41c        ldr     pc, [ip, #1052]!        ; 0x41c

On AARCH64, the plt header size is 32 bytes and the plt entry size is 16
bytes.  The plt section is as follows:

Disassembly of section .plt:
0000000000000560 <__cxa_finalize@plt-0x20>:
 560:   a9bf7bf0        stp     x16, x30, [sp,#-16]!
 564:   90000090        adrp    x16, 10000 <__FRAME_END__+0xf8a8>
 568:   f944be11        ldr     x17, [x16,#2424]
 56c:   9125e210        add     x16, x16, #0x978
 570:   d61f0220        br      x17
 574:   d503201f        nop
 578:   d503201f        nop
 57c:   d503201f        nop

0000000000000580 <__cxa_finalize@plt>:
 580:   90000090        adrp    x16, 10000 <__FRAME_END__+0xf8a8>
 584:   f944c211        ldr     x17, [x16,#2432]
 588:   91260210        add     x16, x16, #0x980
 58c:   d61f0220        br      x17

0000000000000590 <__gmon_start__@plt>:
 590:   90000090        adrp    x16, 10000 <__FRAME_END__+0xf8a8>
 594:   f944c611        ldr     x17, [x16,#2440]
 598:   91262210        add     x16, x16, #0x988
 59c:   d61f0220        br      x17

NOTES:

In addition to ARM and AARCH64, other architectures, such as
s390/alpha/mips/parisc/poperpc/sh/sparc/xtensa also need to consider
this issue.
Signed-off-by: NLi Bin <huawei.libin@huawei.com>
Acked-by: NNamhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: David Tolnay <dtolnay@gmail.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: zhangmengting@huawei.com
Link: http://lkml.kernel.org/r/1496622849-21877-1-git-send-email-huawei.libin@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b2f76050
  15. 12 8月, 2017 3 次提交
    • T
      perf report: Fix module symbol adjustment for s390x · 4a084ecf
      由 Thomas Richter 提交于 
      The 'perf report' tool does not display the addresses of kernel module
symbols correctly.

For example symbol qeth_send_ipa_cmd in kernel module qeth.ko has this
relative address for function qeth_send_ipa_cmd():

  [root@s8360047 linux]# nm -g drivers/s390/net/qeth.ko | fgrep send_ipa_cmd
  0000000000013088 T qeth_send_ipa_cmd

The module is loaded at address:

  [root@s8360047 linux]# cat /sys/module/qeth/sections/.text
  0x000003ff80296d20
  [root@s8360047 linux]#

This should result in a start address of:

  0x13088 + 0x3ff80296d20 = 0x3ff802a9da8

Using crash to verify the address on a live system:

  [root@s8360046 linux]# crash vmlinux

  crash 7.1.9++
  Copyright (C) 2002-2016  Red Hat, Inc.
  Copyright (C) 2004, 2005, 2006, 2010  IBM Corporation

  [...]

  crash> mod -s qeth drivers/s390/net/qeth.ko
       MODULE       NAME        SIZE  OBJECT FILE
       3ff8028d700  qeth      151552  drivers/s390/net/qeth.ko
  crash> sym qeth_send_ipa_cmd
  3ff802a9da8 (T) qeth_send_ipa_cmd [qeth] /root/linux/drivers/s390/net/qeth_core_main.c: 2944
  crash>

Now perf report displays the address of symbol qeth_send_ipa_cmd:
symbol__new:

  qeth_send_ipa_cmd 0x130f0-0x132ce

There is a difference of 0x68 between the entry in the symbol table (see
nm command above) and perf. The difference is from the offset the .text
segment of qeth.ko:

  [root@s8360047 perf]# readelf -a drivers/s390/net/qeth.ko
  Section Headers:
  [Nr] Name              Type             Address           Offset
       Size              EntSize          Flags  Link  Info  Align
  [ 0]                   NULL             0000000000000000  00000000
       0000000000000000  0000000000000000           0     0     0
  [ 1] .note.gnu.build-i NOTE             0000000000000000  00000040
       0000000000000024  0000000000000000   A       0     0     4
  [ 2] .text             PROGBITS         0000000000000000  00000068
       000000000001c8a0  0000000000000000  AX       0     0     8

As seen the .text segment has an offset of 0x68 with start address 0x0.
Therefore 0x68 is added to the address of qeth_send_ipa_cmd and thus
0x13088 + 0x68 = 0x130f0 is displayed.

This is wrong, perf report needs to display the start address of symbol
qeth_send_ipa_cmd at 0x13088 + qeth.ko.text section start address.

The qeth.ko module .text start address is available in the qeth.ko DSO
map. Just identify the kernel module symbols and correct the addresses.

With the fix I see this correct address for symbol: symbol__new:
qeth_send_ipa_cmd 0x3ff802a9da8-0x3ff802a9f86
Signed-off-by: NThomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
LPU-Reference: 20170803134902.47207-1-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-q8lktlpoxb5e3dj52u1s1rw4@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      4a084ecf
    • T
      perf record: Fix wrong size in perf_record_mmap for last kernel module · 9ad4652b
      由 Thomas Richter 提交于 
      During work on perf report for s390 I ran into the following issue:

0 0x318 [0x78]: PERF_RECORD_MMAP -1/0:
        [0x3ff804d6990(0xfffffc007fb2966f) @ 0]:
        x /lib/modules/4.12.0perf1+/kernel/drivers/s390/net/qeth_l2.ko

This is a PERF_RECORD_MMAP entry of the perf.data file with an invalid
module size for qeth_l2.ko (the s390 ethernet device driver).

Even a mainframe does not have 0xfffffc007fb2966f bytes of main memory.

It turned out that this wrong size is created by the perf record
command.  What happens is this function call sequence from
__cmd_record():

  perf_session__new():
    perf_session__create_kernel_maps():
      machine__create_kernel_maps():
        machine__create_modules():   Creates map for all loaded kernel modules.
          modules__parse():   Reads /proc/modules and extracts module name and
                              load address (1st and last column)
            machine__create_module():   Called for every module found in /proc/modules.
                              Creates a new map for every module found and enters
                              module name and start address into the map. Since the
                              module end address is unknown it is set to zero.

This ends up with a kernel module map list sorted by module start
addresses.  All module end addresses are zero.

Last machine__create_kernel_maps() calls function map_groups__fixup_end().
This function iterates through the maps and assigns each map entry's
end address the successor map entry start address. The last entry of the
map group has no successor, so ~0 is used as end to consume the remaining
memory.

Later __cmd_record calls function record__synthesize() which in turn calls
perf_event__synthesize_kernel_mmap() and perf_event__synthesize_modules()
to create PERF_REPORT_MMAP entries into the perf.data file.

On s390 this results in the last module qeth_l2.ko
(which has highest start address, see module table:
        [root@s8360047 perf]# cat /proc/modules
        qeth_l2 86016 1 - Live 0x000003ff804d6000
        qeth 266240 1 qeth_l2, Live 0x000003ff80296000
        ccwgroup 24576 1 qeth, Live 0x000003ff80218000
        vmur 36864 0 - Live 0x000003ff80182000
        qdio 143360 2 qeth_l2,qeth, Live 0x000003ff80002000
        [root@s8360047 perf]# )
to be the last entry and its map has an end address of ~0.

When the PERF_RECORD_MMAP entry is created for kernel module qeth_l2.ko
its start address and length is written. The length is calculated in line:
    event->mmap.len   = pos->end - pos->start;
and results in 0xffffffffffffffff - 0x3ff804d6990(*) = 0xfffffc007fb2966f

(*) On s390 the module start address is actually determined by a __weak function
named arch__fix_module_text_start() in machine__create_module().

I think this improvable. We can use the module size (2nd column of /proc/modules)
to get each loaded kernel module size and calculate its end address.
Only for map entries which do not have a valid end address (end is still zero)
we can use the heuristic we have now, that is use successor start address or ~0.
Signed-off-by: NThomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
LPU-Reference: 20170803134902.47207-2-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-nmoqij5b5vxx7rq2ckwu8iaj@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      9ad4652b
    • M
      perf util: Take elf_name as const string in dso__demangle_sym · 80c345b2
      由 Milian Wolff 提交于 
      The input string is not modified and thus can be passed in as a pointer
to const data.
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20170806212446.24925-3-milian.wolff@kdab.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      80c345b2
  17. 09 6月, 2017 2 次提交
  19. 06 6月, 2017 1 次提交
    • N
      perf symbols: Use correct filename for compressed modules in build-id cache · a09935b8
      由 Namhyung Kim 提交于 
      The decompress_kmodule() decompresses kernel modules in order to load
symbols from it.  In the DSO_BINARY_TYPE__BUILD_ID_CACHE case, it needs
the full file path to extract the file extension to determine the
decompression method.  But overwriting 'name' will fail the
decompression since it might point to a non-existing old file.

Instead, use dso->long_name for having the correct extension and use the
real filename to decompress.

In the DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP case, both names should
be the same.  This allows resolving symbols in the old modules.

Before:

  $ perf report -i perf.data.old | grep scsi_mod
     0.00%  cc1      [scsi_mod]    [k] 0x0000000000004aa6
     0.00%  as       [scsi_mod]    [k] 0x00000000000099e1
     0.00%  cc1      [scsi_mod]    [k] 0x0000000000009830
     0.00%  cc1      [scsi_mod]    [k] 0x0000000000001b8f

After:

     0.00%  cc1      [scsi_mod]    [k] scsi_handle_queue_ramp_up
     0.00%  as       [scsi_mod]    [k] scsi_sg_alloc
     0.00%  cc1      [scsi_mod]    [k] scsi_setup_cmnd
     0.00%  cc1      [scsi_mod]    [k] scsi_get_command
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170531120105.21731-3-namhyung@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      a09935b8
  21. 20 4月, 2017 1 次提交
  23. 27 3月, 2017 1 次提交
  25. 21 3月, 2017 1 次提交
  27. 20 2月, 2017 1 次提交
  29. 04 1月, 2017 1 次提交
  31. 05 9月, 2016 2 次提交
  33. 01 9月, 2016 4 次提交
    • A
      perf symbols: Fixup symbol sizes before picking best ones · 432746f8
      由 Arnaldo Carvalho de Melo 提交于 
      When we call symbol__fixup_duplicate() we use algorithms to pick the
"best" symbols for cases where there are various functions/aliases to an
address, and those check zero size symbols, which, before calling
symbol__fixup_end() are _all_ symbols in a just parsed kallsyms file.

So first fixup the end, then fixup the duplicates.

Found while trying to figure out why 'perf test vmlinux' failed, see the
output of 'perf test -v vmlinux' to see cases where the symbols picked
as best for vmlinux don't match the ones picked for kallsyms.

Cc: Anton Blanchard <anton@samba.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 694bf407 ("perf symbols: Add some heuristics for choosing the best duplicate symbol")
Link: http://lkml.kernel.org/n/tip-rxqvdgr0mqjdxee0kf8i2ufn@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      432746f8
    • A
      perf symbols: Check symbol_conf.allow_aliases for kallsyms loading too · c97b40e4
      由 Arnaldo Carvalho de Melo 提交于 
      We can allow aliases to be kept, but we were checking this just when
loading vmlinux files, be consistent, do it for any symbol table loading
code that calls symbol__fixup_duplicate() by making this function check
.allow_aliases instead.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 680d926a ("perf symbols: Allow symbol alias when loading map for symbol name")
Link: http://lkml.kernel.org/n/tip-z0avp0s6cfjckc4xj3pdfjdz@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      c97b40e4
    • M
      perf probe: Ignore vmlinux buildid if offline kernel is given · 428aff82
      由 Masami Hiramatsu 提交于 
      Ignore the buildid of running kernel when both of --definition and
--vmlinux is given because that kernel should be off-line.

This also skips post-processing of kprobe event for relocating symbol
and checking blacklist, because it can not be done on off-line kernel.

E.g. without this fix perf shows an error as below
  ----
  $ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open
  ./vmlinux-arm with build id 7a1f76dd56e9c4da707cd3d6333f50748141434b not found, continuing without symbols
  Failed to find symbol do_sys_open in kernel
    Error: Failed to add events.
  ----
with this fix, we can get the definition
  ----
  $ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open
  p:probe/do_sys_open do_sys_open+0
  ----
Signed-off-by: NMasami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147214228193.23638.12581984840822162131.stgit@devboxSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      428aff82
    • M
      perf symbols: Demangle symbols for synthesized @plt entries. · 2a8d41b4
      由 Milian Wolff 提交于 
      The symbols in the synthesized @plt entries where not demangled before,
i.e. we could end up with entries such as:

    $ perf report
    Samples: 7K of event 'cycles:ppp', Event count (approx.): 6223833141
    Children      Self  Command          Shared Object           Symbol
    -   93.63%    28.89%  lab_mandelbrot   lab_mandelbrot        [.] main
        - 73.81% main
            - 33.57% hypot
              27.76% __hypot_finite
              15.97% __muldc3
               2.90% __muldc3@plt
               2.40% _ZNK6QImage6heightEv@plt
             + 2.14% QColor::rgb
               1.94% _ZNK6QImage5widthEv@plt
               1.92% cabs@plt

This patch remedies this issue by also applying demangling to the
synthesized symbols. The output for the above is now:

    $ perf report
    Samples: 7K of event 'cycles:ppp', Event count (approx.): 6223833141
    Children      Self  Command          Shared Object           Symbol
    -   93.63%    28.89%  lab_mandelbrot   lab_mandelbrot        [.] main
        - 73.81% main
            - 33.57% hypot
              27.76% __hypot_finite
              15.97% __muldc3
               2.90% __muldc3@plt
               2.40% QImage::height() const@plt
             + 2.14% QColor::rgb
               1.94% QImage::width() const@plt
               1.92% cabs@plt
Signed-off-by: NMilian Wolff <milian.wolff@kdab.com>
LPU-Reference: 20160830114102.30863-1-milian.wolff@kdab.com
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      2a8d41b4
  35. 16 8月, 2016 1 次提交
  37. 13 7月, 2016 2 次提交
    • D
      perf symbols: Add Rust demangling · cae15db7
      由 David Tolnay 提交于 
      Rust demangling is another step after bfd demangling. Add a diagnosis to
identify mangled Rust symbols based on the hash that the Rust mangler appends
as the last path component, as well as other characteristics.  Add a demangler
to reconstruct the original symbol.

Committer notes:

How I tested it:

Enabled COPR on Fedora 24 and then installed the 'rust-binary' package,
with it:

  $ cat src/main.rs
  fn main() {
      println!("Hello, world!");
  }
  $ cat Cargo.toml
  [package]

  name = "hello_world"
  version = "0.0.1"
  authors = [ "Arnaldo Carvalho de Melo <acme@kernel.org>" ]

  $ perf record cargo bench
   Compiling hello_world v0.0.1 (file:///home/acme/projects/hello_world)
     Running target/release/hello_world-d4b9dab4b2a47d75

  running 0 tests

  test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured

  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.096 MB perf.data (1457 samples) ]
  $

Before this patch:

  $ perf report --stdio --dsos librbml-e8edd0fd.so
  # dso: librbml-e8edd0fd.so
  #
  # Total Lost Samples: 0
  #
  # Samples: 1K of event 'cycles:u'
  # Event count (approx.): 979599126
  #
  # Overhead  Command  Symbol
  # ........  .......  .............................................................................................................
  #
       1.78%  rustc    [.] rbml::reader::maybe_get_doc::hb9d387df6024b15b
       1.50%  rustc    [.] _$LT$reader..DocsIterator$LT$$u27$a$GT$$u20$as$u20$std..iter..Iterator$GT$::next::hd9af9e60d79a35c8
       1.20%  rustc    [.] rbml::reader::doc_at::hc88107fba445af31
       0.46%  rustc    [.] _$LT$reader..TaggedDocsIterator$LT$$u27$a$GT$$u20$as$u20$std..iter..Iterator$GT$::next::h0cb40e696e4bb489
       0.35%  rustc    [.] rbml::reader::Decoder::_next_int::h66eef7825a398bc3
       0.29%  rustc    [.] rbml::reader::Decoder::_next_sub::h8e5266005580b836
       0.15%  rustc    [.] rbml::reader::get_doc::h094521c645459139
       0.14%  rustc    [.] _$LT$reader..Decoder$LT$$u27$doc$GT$$u20$as$u20$serialize..Decoder$GT$::read_u32::h0acea2fff9669327
       0.07%  rustc    [.] rbml::reader::Decoder::next_doc::h6714d469c9dfaf91
       0.07%  rustc    [.] _ZN4rbml6reader10doc_as_u6417h930b740aa94f1d3aE@plt
       0.06%  rustc    [.] _fini
  $

After:

  $ perf report --stdio --dsos librbml-e8edd0fd.so
  # dso: librbml-e8edd0fd.so
  #
  # Total Lost Samples: 0
  #
  # Samples: 1K of event 'cycles:u'
  # Event count (approx.): 979599126
  #
  # Overhead  Command  Symbol
  # ........  .......  .................................................................
  #
     1.78%  rustc    [.] rbml::reader::maybe_get_doc
     1.50%  rustc    [.] <reader::DocsIterator<'a> as std::iter::Iterator>::next
     1.20%  rustc    [.] rbml::reader::doc_at
     0.46%  rustc    [.] <reader::TaggedDocsIterator<'a> as std::iter::Iterator>::next
     0.35%  rustc    [.] rbml::reader::Decoder::_next_int
     0.29%  rustc    [.] rbml::reader::Decoder::_next_sub
     0.15%  rustc    [.] rbml::reader::get_doc
     0.14%  rustc    [.] <reader::Decoder<'doc> as serialize::Decoder>::read_u32
     0.07%  rustc    [.] rbml::reader::Decoder::next_doc
     0.07%  rustc    [.] _ZN4rbml6reader10doc_as_u6417h930b740aa94f1d3aE@plt
     0.06%  rustc    [.] _fini
  $
Signed-off-by: NDavid Tolnay <dtolnay@gmail.com>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/5780B7FA.3030602@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      cae15db7
    • A
      perf tools: Add feature detection for gelf_getnote() · 1c1a3a47
      由 Arnaldo Carvalho de Melo 提交于 
      That is not present on some libelf implementations, such as the one used
in Alpine Linux: libelf-0.8.13.

This ends up disabling the SDT code, that relies on this function.

One alternative would be to provide an weak fallback implementation or
the open coded variant used by the buildid sysfs notes reading code.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-82lh22ybedy9b9lych8xj12g@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      1c1a3a47