Re: [PATCH v2 3/4] perf record: enable runtime trace compression

From: Jiri Olsa
Date: Tue Feb 12 2019 - 08:09:02 EST


On Mon, Feb 11, 2019 at 11:23:40PM +0300, Alexey Budankov wrote:

SNIP

> @@ -774,6 +775,8 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli
> struct perf_mmap *maps;
> int trace_fd = rec->data.file.fd;
> off_t off;
> + struct perf_session *session = rec->session;
> + perf_mmap__compress_fn_t compress_fn;
>
> if (!evlist)
> return 0;
> @@ -785,6 +788,9 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli
> if (overwrite && evlist->bkw_mmap_state != BKW_MMAP_DATA_PENDING)
> return 0;
>
> + compress_fn = (record__comp_enabled(rec) ?
> + perf_session__zstd_compress : perf_session__zstd_copy);
> +

I don't follow what's the perf_session__zstd_copy function for..?

for !record__comp_enabled case we seem not to use it
and calling the current perf_mmap__push interface

however I dont see point to have this function at all

jirka


> if (record__aio_enabled(rec))
> off = record__aio_get_pos(trace_fd);
>
> @@ -799,11 +805,21 @@ static int record__mmap_read_evlist(struct record *rec, struct perf_evlist *evli
> map->flush = MMAP_FLUSH_DEFAULT;
> }
> if (!record__aio_enabled(rec)) {
> - if (perf_mmap__push(map, rec, record__pushfn) != 0) {
> - if (sync)
> - map->flush = flush;
> - rc = -1;
> - goto out;
> + if (!record__comp_enabled(rec)) {
> + if (perf_mmap__push(map, rec, record__pushfn) != 0) {
> + if (sync)
> + map->flush = flush;
> + rc = -1;
> + goto out;
> + }
> + } else {
> + if (perf_mmap__pack(map, rec, record__pushfn,
> + compress_fn, session) != 0) {
> + if (sync)
> + map->flush = flush;
> + rc = -1;
> + goto out;
> + }

SNIP