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Source line numbers in the primary call schedule?

I use perf record -a --call-graph dwarf -p XXX sleep 1

to record some function calls and then perf report

view this data, however it would be very helpful if I could also see the source line numbers so that I know exactly where each function call was called. For example:

-   4.18%  testbinary  testbinary                [.] malloc 
   - malloc 
      - 99.57% operator new(unsigned long)
         + 7.28% MyFunction()

I want to know exactly where MyFunction()

those are in new operators

(without guessing by looking at the entire function source code)

PS: Binary is compiled with -m64 -O2 -ggdb3

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2 answers


Fragments (complete lines) of the source code are printed by the performance in annotated mode ( man page ; relevant part of the Perf Tutorial ). Use perf annotate -s=MyFunction

or perf report

, scroll down to the subtree where your MyFunction is the root of the tree (the line where the battery life is, you can use the command /to find it) and then select the button a(or Enterthen annotate "MyFunction").

The source code and its lines should be visible next to the conveyor lines in annotation mode. http://man7.org/linux/man-pages/man1/perf-annotate.1.html

This command reads the input file and displays the annotated version of the code. If the object file has debug symbols, then the source code will be displayed next to the assembly code.

   -l, --print-line
       Print matching source lines (may be slow).
  --source
      Interleave source code with assembly code. Enabled by default,
       disable with `--no-source`.
   -s, --symbol=<symbol>
       Symbol to annotate.


Perf report can use srclines when sorting ( --sort=

), but the instructions are unclear. Its a doc man page --source

too, but apparently it is only used in Annotate some_function: http://man7.org/linux/man-pages/man1/perf-report.1.html

  --source
       Interleave source code with assembly code. Enabled by default,
       disable with --no-source.
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I accidentally discovered this is poorly documented in perf script

, but this applies to other commands as well: the option -F

takes srcline

. So you can do -F+srcline

to add the row number to the existing columns.

Example: perf report -g fractal -F+period,srcline 



Samples: 22K of event 'cycles:u', Event count (approx.): 13031011295
  Children      Self        Period  Source:Line                           Command  Shared Object        Symbol
+   99.98%    38.76%    5051224000  test.cpp:7                            a        a                    [.] fib
+   96.42%     0.00%             0  _start+94372992700461                 a        a                    [.] _start
+   96.42%     0.00%             0  __libc_start_main+140304673091826     a        libc-2.29.so         [.] __libc_start_main
+   96.42%     0.00%             0  test.cpp:13                           a        a                    [.] main
+   21.47%    21.47%    2797741850  test.cpp:8                            a        a                    [.] fib
+   16.69%    16.69%    2174469736  test.cpp:4                            a        a                    [.] fib
+   16.37%    16.36%    2132462705  test.cpp:6                            a        a                    [.] fib
+    6.69%     6.69%     871128215  test.cpp:5                            a        a                    [.] fib
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