Linux kernel source tree
Go to file
Wei Li 11db1ad451 perf annotate: Fix getting source line failure
The output of "perf annotate -l --stdio xxx" changed since commit 425859ff0d
("perf annotate: No need to calculate notes->start twice") removed notes->start
assignment in symbol__calc_lines(). It will get failed in
find_address_in_section() from symbol__tty_annotate() subroutine as the
a2l->addr is wrong. So the annotate summary doesn't report the line number of
source code correctly.

Before fix:

  liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ cat common_while_1.c
  void hotspot_1(void)
  {
	volatile int i;

	for (i = 0; i < 0x10000000; i++);
	for (i = 0; i < 0x10000000; i++);
	for (i = 0; i < 0x10000000; i++);
  }

  int main(void)
  {
	hotspot_1();

	return 0;
  }
  liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ gcc common_while_1.c -g -o common_while_1

  liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ sudo ./perf record ./common_while_1
  [ perf record: Woken up 2 times to write data ]
  [ perf record: Captured and wrote 0.488 MB perf.data (12498 samples) ]
  liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ sudo ./perf annotate -l -s hotspot_1 --stdio

  Sorted summary for file /home/liwei/main_code/hulk_work/hulk/tools/perf/common_while_1
  ----------------------------------------------

   19.30 common_while_1[32]
   19.03 common_while_1[4e]
   19.01 common_while_1[16]
    5.04 common_while_1[13]
    4.99 common_while_1[4b]
    4.78 common_while_1[2c]
    4.77 common_while_1[10]
    4.66 common_while_1[2f]
    4.59 common_while_1[51]
    4.59 common_while_1[35]
    4.52 common_while_1[19]
    4.20 common_while_1[56]
    0.51 common_while_1[48]
   Percent |      Source code & Disassembly of common_while_1 for cycles:ppp (12480 samples, percent: local period)
  -----------------------------------------------------------------------------------------------------------------
         :
         :
         :
         :         Disassembly of section .text:
         :
         :         00000000000005fa <hotspot_1>:
         :         hotspot_1():
         :         void hotspot_1(void)
         :         {
    0.00 :   5fa:   push   %rbp
    0.00 :   5fb:   mov    %rsp,%rbp
         :                 volatile int i;
         :
         :                 for (i = 0; i < 0x10000000; i++);
    0.00 :   5fe:   movl   $0x0,-0x4(%rbp)
    0.00 :   605:   jmp    610 <hotspot_1+0x16>
    0.00 :   607:   mov    -0x4(%rbp),%eax
   common_while_1[10]    4.77 :   60a:   add    $0x1,%eax
   common_while_1[13]    5.04 :   60d:   mov    %eax,-0x4(%rbp)
   common_while_1[16]   19.01 :   610:   mov    -0x4(%rbp),%eax
   common_while_1[19]    4.52 :   613:   cmp    $0xfffffff,%eax
      0.00 :   618:   jle    607 <hotspot_1+0xd>
           :                 for (i = 0; i < 0x10000000; i++);
  ...

After fix:

  liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ sudo ./perf record ./common_while_1
  [ perf record: Woken up 2 times to write data ]
  [ perf record: Captured and wrote 0.488 MB perf.data (12500 samples) ]
  liwei@euler:~/main_code/hulk_work/hulk/tools/perf$ sudo ./perf annotate -l -s hotspot_1 --stdio

  Sorted summary for file /home/liwei/main_code/hulk_work/hulk/tools/perf/common_while_1
  ----------------------------------------------

   33.34 common_while_1.c:5
   33.34 common_while_1.c:6
   33.32 common_while_1.c:7
   Percent |      Source code & Disassembly of common_while_1 for cycles:ppp (12482 samples, percent: local period)
  -----------------------------------------------------------------------------------------------------------------
         :
         :
         :
         :         Disassembly of section .text:
         :
         :         00000000000005fa <hotspot_1>:
         :         hotspot_1():
         :         void hotspot_1(void)
         :         {
    0.00 :   5fa:   push   %rbp
    0.00 :   5fb:   mov    %rsp,%rbp
         :                 volatile int i;
         :
         :                 for (i = 0; i < 0x10000000; i++);
    0.00 :   5fe:   movl   $0x0,-0x4(%rbp)
    0.00 :   605:   jmp    610 <hotspot_1+0x16>
    0.00 :   607:   mov    -0x4(%rbp),%eax
   common_while_1.c:5    4.70 :   60a:   add    $0x1,%eax
    4.89 :   60d:   mov    %eax,-0x4(%rbp)
   common_while_1.c:5   19.03 :   610:   mov    -0x4(%rbp),%eax
   common_while_1.c:5    4.72 :   613:   cmp    $0xfffffff,%eax
    0.00 :   618:   jle    607 <hotspot_1+0xd>
         :                 for (i = 0; i < 0x10000000; i++);
    0.00 :   61a:   movl   $0x0,-0x4(%rbp)
    0.00 :   621:   jmp    62c <hotspot_1+0x32>
    0.00 :   623:   mov    -0x4(%rbp),%eax
   common_while_1.c:6    4.54 :   626:   add    $0x1,%eax
    4.73 :   629:   mov    %eax,-0x4(%rbp)
   common_while_1.c:6   19.54 :   62c:   mov    -0x4(%rbp),%eax
   common_while_1.c:6    4.54 :   62f:   cmp    $0xfffffff,%eax
  ...

Signed-off-by: Wei Li <liwei391@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 425859ff0d ("perf annotate: No need to calculate notes->start twice")
Link: http://lkml.kernel.org/r/20190221095716.39529-1-liwei391@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-21 17:00:35 -03:00
arch x86/kprobes: Prohibit probing on IRQ handlers directly 2019-02-13 08:16:39 +01:00
block blk-mq: fix a hung issue when fsync 2019-01-30 08:53:54 -07:00
certs kbuild: remove redundant target cleaning on failure 2019-01-06 09:46:51 +09:00
crypto crypto: sm3 - fix undefined shift by >= width of value 2019-01-10 21:37:32 +08:00
Documentation Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-02-03 09:08:12 -08:00
drivers coresight: Use event attributes for sink selection 2019-02-06 10:00:39 -03:00
firmware kbuild: change filechk to surround the given command with { } 2019-01-06 09:46:51 +09:00
fs for-5.0-rc4-tag 2019-02-03 08:48:33 -08:00
include coresight: perf: Add "sinks" group to PMU directory 2019-02-06 10:00:39 -03:00
init psi: clarify the Kconfig text for the default-disable option 2019-02-01 15:46:24 -08:00
ipc ipc: IPCMNI limit check for semmni 2018-10-31 08:54:14 -07:00
kernel kprobes: Prohibit probing on lockdep functions 2019-02-13 08:16:41 +01:00
lib kprobes: Prohibit probing on bsearch() 2019-02-13 08:16:41 +01:00
LICENSES This is a fairly typical cycle for documentation. There's some welcome 2018-10-24 18:01:11 +01:00
mm mm: migrate: don't rely on __PageMovable() of newpage after unlocking it 2019-02-01 15:46:24 -08:00
net net: set default network namespace in init_dummy_netdev() 2019-01-29 11:29:55 -08:00
samples samples/bpf: workaround clang asm goto compilation errors 2019-01-15 20:57:30 +01:00
scripts Bug fixes for gcc-plugins 2019-01-21 13:07:03 +13:00
security apparmor: Fix aa_label_build() error handling for failed merges 2019-02-01 08:01:39 -08:00
sound sound fixes for 5.0-rc5 2019-01-31 10:00:00 -08:00
tools perf annotate: Fix getting source line failure 2019-02-21 17:00:35 -03:00
usr user/Makefile: Fix typo and capitalization in comment section 2018-12-11 00:18:03 +09:00
virt KVM: validate userspace input in kvm_clear_dirty_log_protect() 2019-01-11 18:38:07 +01:00
.clang-format clang-format: Update .clang-format with the latest for_each macro list 2019-01-19 19:26:06 +01:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support for DT binding schema checks 2018-12-13 09:41:32 -06:00
.mailmap A few early MIPS fixes for 4.21: 2019-01-05 12:48:25 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Add CREDITS entry for Shaohua Li 2019-01-04 14:27:09 -07:00
Kbuild kbuild: use assignment instead of define ... endef for filechk_* rules 2019-01-06 10:22:35 +09:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-02-03 09:08:12 -08:00
Makefile Linux 5.0-rc5 2019-02-03 13:48:04 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.