Re: [PATCH v2 6/7] perf scripts python cs-etm: Add start and stop arguments

[Leo Yan <leo.yan@arm.com>]

On 9/12/24 16:11, James Clark wrote:>
> Make it possible to only disassemble a range of timestamps or sample
> indexes. This will be used by the test to limit the runtime, but it's
> also useful for users.
> 
> Signed-off-by: James Clark <james.clark@linaro.org>
> ---
>   .../scripts/python/arm-cs-trace-disasm.py     | 22 +++++++++++++++++--
>   1 file changed, 20 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 02e957d037ea..a097995d8e7b 100755
> --- a/tools/perf/scripts/python/arm-cs-trace-disasm.py
> +++ b/tools/perf/scripts/python/arm-cs-trace-disasm.py
> @@ -55,6 +55,11 @@ args.add_argument("-k", "--vmlinux",
>   args.add_argument("-d", "--objdump", nargs="?", const=default_objdump(),
>                    help="Show disassembly. Can also be used to change the objdump path"),
>   args.add_argument("-v", "--verbose", action="store_true", help="Enable debugging log")
> +args.add_argument("--start-time", type=int, help="Time of sample to start from")
> +args.add_argument("--stop-time", type=int, help="Time of sample to stop at")
> +args.add_argument("--start-sample", type=int, help="Index of sample to start from")
> +args.add_argument("--stop-sample", type=int, help="Index of sample to stop at")
> +

It is good to validate the ranges for time and sample indexes, in case
the user passes unexpected values and can directly report the error.

BTW, I think it is good to clarify the time is based on monotonic clock
but not wall-clock time.

With above changes, LGTM:

Reviewed-by: Leo Yan <leo.yan@arm.com>

>   options = args.parse_args()
> 
>   # Initialize global dicts and regular expression
> @@ -63,6 +68,7 @@ cpu_data = dict()
>   disasm_re = re.compile(r"^\s*([0-9a-fA-F]+):")
>   disasm_func_re = re.compile(r"^\s*([0-9a-fA-F]+)\s.*:")
>   cache_size = 64*1024
> +sample_idx = -1
> 
>   glb_source_file_name   = None
>   glb_line_number                = None
> @@ -151,10 +157,10 @@ def print_disam(dso_fname, dso_start, start_addr, stop_addr):
> 
>   def print_sample(sample):
>          print("Sample = { cpu: %04d addr: 0x%016x phys_addr: 0x%016x ip: 0x%016x " \
> -             "pid: %d tid: %d period: %d time: %d }" % \
> +             "pid: %d tid: %d period: %d time: %d index: %d}" % \
>                (sample['cpu'], sample['addr'], sample['phys_addr'], \
>                 sample['ip'], sample['pid'], sample['tid'], \
> -              sample['period'], sample['time']))
> +              sample['period'], sample['time'], sample_idx))
> 
>   def trace_begin():
>          print('ARM CoreSight Trace Data Assembler Dump')
> @@ -216,6 +222,7 @@ def print_srccode(comm, param_dict, sample, symbol, dso):
>   def process_event(param_dict):
>          global cache_size
>          global options
> +       global sample_idx
> 
>          sample = param_dict["sample"]
>          comm = param_dict["comm"]
> @@ -231,6 +238,17 @@ def process_event(param_dict):
>          ip = sample["ip"]
>          addr = sample["addr"]
> 
> +       sample_idx += 1
> +
> +       if (options.start_time and sample["time"] < options.start_time):
> +               return
> +       if (options.stop_time and sample["time"] > options.stop_time):
> +               exit(0)
> +       if (options.start_sample and sample_idx < options.start_sample):
> +               return
> +       if (options.stop_sample and sample_idx > options.stop_sample):
> +               exit(0)
> +
>          if (options.verbose == True):
>                  print("Event type: %s" % name)
>                  print_sample(sample)
> --
> 2.34.1
>