Re: [PATCH v2 02/16] perf auxtrace: Allow number of queues to be specified

From: James Clark
Date: Wed Jun 05 2024 - 04:26:12 EST




On 05/06/2024 06:26, Adrian Hunter wrote:
> On 4/06/24 17:30, James Clark wrote:
>> Currently it's only possible to initialize with the default number of
>> queues and then use auxtrace_queues__add_event() to grow the array. But
>> that's problematic if you don't have a real event to pass into that
>> function yet.
>>
>> The queues hold a void *priv member to store custom state, and for
>> Coresight we want to create decoders upfront before receiving data, so
>> add a new function that allows pre-allocating queues. One reason to do
>> this is because we might need to store metadata (HW_ID events) that
>> effects other queues, but never actually receive auxtrace data on that
>> queue.
>>
>> Signed-off-by: James Clark <james.clark@xxxxxxx>
>
> Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>
> Again ;-)
>

Oops yeah I should have picked that up. This one was already applied to
perf-tools-next as well.

Thanks

>> ---
>> tools/perf/util/auxtrace.c | 9 +++++++--
>> tools/perf/util/auxtrace.h | 1 +
>> 2 files changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/tools/perf/util/auxtrace.c b/tools/perf/util/auxtrace.c
>> index 3684e6009b63..563b6c4fca31 100644
>> --- a/tools/perf/util/auxtrace.c
>> +++ b/tools/perf/util/auxtrace.c
>> @@ -218,15 +218,20 @@ static struct auxtrace_queue *auxtrace_alloc_queue_array(unsigned int nr_queues)
>> return queue_array;
>> }
>>
>> -int auxtrace_queues__init(struct auxtrace_queues *queues)
>> +int auxtrace_queues__init_nr(struct auxtrace_queues *queues, int nr_queues)
>> {
>> - queues->nr_queues = AUXTRACE_INIT_NR_QUEUES;
>> + queues->nr_queues = nr_queues;
>> queues->queue_array = auxtrace_alloc_queue_array(queues->nr_queues);
>> if (!queues->queue_array)
>> return -ENOMEM;
>> return 0;
>> }
>>
>> +int auxtrace_queues__init(struct auxtrace_queues *queues)
>> +{
>> + return auxtrace_queues__init_nr(queues, AUXTRACE_INIT_NR_QUEUES);
>> +}
>> +
>> static int auxtrace_queues__grow(struct auxtrace_queues *queues,
>> unsigned int new_nr_queues)
>> {
>> diff --git a/tools/perf/util/auxtrace.h b/tools/perf/util/auxtrace.h
>> index 55702215a82d..8a6ec9565835 100644
>> --- a/tools/perf/util/auxtrace.h
>> +++ b/tools/perf/util/auxtrace.h
>> @@ -521,6 +521,7 @@ int auxtrace_mmap__read_snapshot(struct mmap *map,
>> struct perf_tool *tool, process_auxtrace_t fn,
>> size_t snapshot_size);
>>
>> +int auxtrace_queues__init_nr(struct auxtrace_queues *queues, int nr_queues);
>> int auxtrace_queues__init(struct auxtrace_queues *queues);
>> int auxtrace_queues__add_event(struct auxtrace_queues *queues,
>> struct perf_session *session,
>