Re: [PATCH v7 20/20] perf session: Load data directory files for analysis

From: Namhyung Kim
Date: Wed Jun 30 2021 - 02:14:58 EST


On Tue, Jun 22, 2021 at 1:43 AM Alexey Bayduraev
<alexey.v.bayduraev@xxxxxxxxxxxxxxx> wrote:
>
> Load data directory files and provide basic raw dump and aggregated
> analysis support of data directories in report mode, still with no
> memory consumption optimizations.
>
> Design and implementation are based on the prototype [1], [2].
>
> [1] git clone https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git -b perf/record_threads
> [2] https://lore.kernel.org/lkml/20180913125450.21342-1-jolsa@xxxxxxxxxx/
>
> Suggested-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> Signed-off-by: Alexey Bayduraev <alexey.v.bayduraev@xxxxxxxxxxxxxxx>
> ---
> tools/perf/util/session.c | 129 ++++++++++++++++++++++++++++++++++++++
> 1 file changed, 129 insertions(+)
>
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index fe25abf83b80..2c0eb126cdbb 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -65,6 +65,7 @@ struct reader_state {
> u64 data_size;
> u64 head;
> bool eof;
> + u64 size;
> };
>
> enum {
> @@ -2322,6 +2323,7 @@ reader__read_event(struct reader *rd, struct perf_session *session,
> if (skip)
> size += skip;
>
> + st->size += size;
> st->head += size;
> st->file_pos += size;
>
> @@ -2421,6 +2423,130 @@ static int __perf_session__process_events(struct perf_session *session)
> return err;
> }
>
> +/*
> + * This function reads, merge and process directory data.
> + * It assumens the version 1 of directory data, where each
> + * data file holds per-cpu data, already sorted by kernel.
> + */
> +static int __perf_session__process_dir_events(struct perf_session *session)
> +{
> + struct perf_data *data = session->data;
> + struct perf_tool *tool = session->tool;
> + int i, ret = 0, readers = 1;
> + struct ui_progress prog;
> + u64 total_size = perf_data__size(session->data);
> + struct reader *rd;
> +
> + perf_tool__fill_defaults(tool);
> +
> + ui_progress__init_size(&prog, total_size, "Sorting events...");
> +
> + for (i = 0; i < data->dir.nr; i++) {
> + if (data->dir.files[i].size)
> + readers++;
> + }
> +
> + rd = session->readers = zalloc(readers * sizeof(struct reader));
> + if (!rd)
> + return -ENOMEM;
> + session->nr_readers = readers;
> + readers = 0;
> +
> + rd[readers] = (struct reader) {
> + .fd = perf_data__fd(session->data),
> + .path = session->data->file.path,
> + .data_size = session->header.data_size,
> + .data_offset = session->header.data_offset,
> + .in_place_update = session->data->in_place_update,
> + };
> + ret = reader__init(&rd[readers], NULL);
> + if (ret)
> + goto out_err;
> + ret = reader__mmap(&rd[readers], session);
> + if (ret != READER_OK) {
> + if (ret == READER_EOF)
> + ret = -EINVAL;
> + goto out_err;
> + }
> + readers++;
> +
> + for (i = 0; i < data->dir.nr; i++) {
> + if (data->dir.files[i].size) {

Just one more nitpicking. :)

You can save an indent depth by having

if (!data->dir.files[i].size)
continue;

Thanks,
Namhyung


> + rd[readers] = (struct reader) {
> + .fd = data->dir.files[i].fd,
> + .path = data->dir.files[i].path,
> + .data_size = data->dir.files[i].size,
> + .data_offset = 0,
> + .in_place_update = session->data->in_place_update,
> + };
> + ret = reader__init(&rd[readers], NULL);
> + if (ret)
> + goto out_err;
> + ret = reader__mmap(&rd[readers], session);
> + if (ret != READER_OK) {
> + if (ret == READER_EOF)
> + ret = -EINVAL;
> + goto out_err;
> + }
> + readers++;
> + }
> + }