Re: [PATCH 2/2] perf: cs-etm: Fix corrupt inject files when only last branch option is enabled

From: James Clark
Date: Tue Feb 22 2022 - 10:49:40 EST




On 15/02/2022 15:07, Arnaldo Carvalho de Melo wrote:
> Em Sat, Feb 12, 2022 at 12:05:16AM +0800, Leo Yan escreveu:
>> On Thu, Feb 10, 2022 at 08:06:20PM +0000, James Clark wrote:
>>> Perf inject with Coresight data generates files that cannot be opened
>>> when only the last branch option is specified:
>>>
>>> perf inject -i perf.data --itrace=l -o inject.data
>>> perf script -i inject.data
>>> 0x33faa8 [0x8]: failed to process type: 9 [Bad address]
>>>
>>> This is because cs_etm__synth_instruction_sample() is called even when
>>> the sample type for instructions hasn't been setup. Last branch records
>>> are attached to instruction samples so it doesn't make sense to generate
>>> them when --itrace=i isn't specified anyway.
>>>
>>> This change disables all calls of cs_etm__synth_instruction_sample()
>>> unless --itrace=i is specified, resulting in a file with no samples if
>>> only --itrace=l is provided, rather than a bad file.
>>>
>>> Signed-off-by: James Clark <james.clark@xxxxxxx>
>>
>> Reviewed-by: Leo Yan <leo.yan@xxxxxxxxxx>
>
> Thanks, applied.
>
> - Arnaldo
>

Thanks Leo and Arnaldo!

>
>>> ---
>>> tools/perf/util/cs-etm.c | 2 ++
>>> 1 file changed, 2 insertions(+)
>>>
>>> diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
>>> index 796a065a500e..8b95fb3c4d7b 100644
>>> --- a/tools/perf/util/cs-etm.c
>>> +++ b/tools/perf/util/cs-etm.c
>>> @@ -1553,6 +1553,7 @@ static int cs_etm__flush(struct cs_etm_queue *etmq,
>>> goto swap_packet;
>>>
>>> if (etmq->etm->synth_opts.last_branch &&
>>> + etmq->etm->synth_opts.instructions &&
>>> tidq->prev_packet->sample_type == CS_ETM_RANGE) {
>>> u64 addr;
>>>
>>> @@ -1610,6 +1611,7 @@ static int cs_etm__end_block(struct cs_etm_queue *etmq,
>>> * the trace.
>>> */
>>> if (etmq->etm->synth_opts.last_branch &&
>>> + etmq->etm->synth_opts.instructions &&
>>> tidq->prev_packet->sample_type == CS_ETM_RANGE) {
>>> u64 addr;
>>>
>>> --
>>> 2.28.0
>>>
>