[PATCH V2 5/5] Adjust objdump start/end range per map pgoff parameter

[Leo Yan]

On 8/26/2024 10:35 PM, Steve Clevenger wrote:
> 
> Changes in V2:
>   - Updated mailing list distribution
> 
> Extract map_pgoff parameter from the dictionary, and adjust start/end
> range passed to objdump based on the value.
> 
> The start_addr/stop_addr address checks are changed to print a warning
> only if verbose == True. This script repeatedly sees a zero value passed
> in for
>       start_addr = cpu_data[str(cpu) + 'addr']
> 
> These zero values are not a new problem. The start_addr/stop_addr warning
> clutters the instruction trace output, hence this change.
> 
> Signed-off-by: Steve Clevenger <scclevenger at os.amperecomputing.com>
> ---
>  .../perf/scripts/python/arm-cs-trace-disasm.py  | 17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/scripts/python/arm-cs-trace-disasm.py b/tools/perf/scripts/python/arm-cs-trace-disasm.py
> index d973c2baed1c..6bf806078f9a 100755
> --- a/tools/perf/scripts/python/arm-cs-trace-disasm.py
> +++ b/tools/perf/scripts/python/arm-cs-trace-disasm.py
> @@ -187,6 +187,7 @@ def process_event(param_dict):
>         dso_start = get_optional(param_dict, "dso_map_start")
>         dso_end = get_optional(param_dict, "dso_map_end")
>         symbol = get_optional(param_dict, "symbol")
> +       map_pgoff = get_optional(param_dict, "map_pgoff")
> 
>         cpu = sample["cpu"]
>         ip = sample["ip"]
> @@ -250,13 +251,25 @@ def process_event(param_dict):
>                 return
> 
>         if (start_addr < int(dso_start) or start_addr > int(dso_end)):
> -               print("Start address 0x%x is out of range [ 0x%x .. 0x%x ] for dso %s" % (start_addr, int(dso_start), int(dso_end), dso))
> +               if (options.verbose == True):
> +                       print("Start address 0x%x is out of range [ 0x%x .. 0x%x ] for dso %s" % (start_addr, int(dso_start), int(dso_end), dso))
>                 return
> 
>         if (stop_addr < int(dso_start) or stop_addr > int(dso_end)):
> -               print("Stop address 0x%x is out of range [ 0x%x .. 0x%x ] for dso %s" % (stop_addr, int(dso_start), int(dso_end), dso))
> +               if (options.verbose == True):
> +                       print("Stop address 0x%x is out of range [ 0x%x .. 0x%x ] for dso %s" % (stop_addr, int(dso_start), int(dso_end), dso))
>                 return
> 
> +       if map_pgoff != None and map_pgoff != '[unknown]':
> +               if (dso == "[kernel.kallsyms]"):
> +                       dso_vm_start = 0
> +                       map_pgoff = '[unknown]'
> +               else:
> +                       dso_vm_start = int(dso_start)
> +                       start_addr += map_pgoff
> +                       stop_addr += map_pgoff
> +                       map_pgoff = '[unknown]'

Every sample has its own field `map_pgoff`. So I am confused why we need the
sentence: map_pgoff = '[unknown]'. And you can see with above change, we will
set dso_vm_start delicately with below code section.

How about a simple change like below?

@@ -267,7 +268,7 @@ def process_event(param_dict):

  dso_fname = get_dso_file_path(dso, dso_bid)
  if path.exists(dso_fname):
-     print_disam(dso_fname, dso_vm_start, start_addr, stop_addr)
+     print_disam(dso_fname, dso_vm_start, start_addr + map_pgoff, stop_addr +
map_pgoff)

If this change does not work, I am curious if anything we missed to handle in
the perf's C code (frontend).

Thanks,
Leo

>         if (options.objdump_name != None):
>                 # It doesn't need to decrease virtual memory offset for disassembly
>                 # for kernel dso and executable file dso, so in this case we set
> --
> 2.25.1
>