Re: [PATCH v11 01/10] perf record: Prepare mmap multiple evlists

From: Arnaldo Carvalho de Melo
Date: Mon Jun 27 2016 - 13:45:53 EST


Em Mon, Jun 27, 2016 at 10:24:03AM +0000, Wang Nan escreveu:
> Following commits introduce multiple evlists to record. This patch
> extracts perf_evlist__mmap_ex() processing to a new function, creates
> record__mmap() and record__mmap_evlist() to wrap perf_evlist__mmap_ex()
> and its error processing. They will be improvemented to create mmap
> for all evlists.

Thanks for following my suggestion, as you can see this patch has value
irrespective of the other patches in this series and can be applied
straight away.

- Arnaldo

> Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> Cc: Zefan Li <lizefan@xxxxxxxxxx>
> Cc: He Kuang <hekuang@xxxxxxxxxx>
> Cc: Nilay Vaish <nilayvaish@xxxxxxxxx>
> ---
> tools/perf/builtin-record.c | 56 +++++++++++++++++++++++++++++----------------
> 1 file changed, 36 insertions(+), 20 deletions(-)
>
> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> index 81411b1..7eb8d7d 100644
> --- a/tools/perf/builtin-record.c
> +++ b/tools/perf/builtin-record.c
> @@ -342,6 +342,40 @@ int auxtrace_record__snapshot_start(struct auxtrace_record *itr __maybe_unused)
>
> #endif
>
> +static int record__mmap_evlist(struct record *rec,
> + struct perf_evlist *evlist)
> +{
> + struct record_opts *opts = &rec->opts;
> + char msg[512];
> +
> + if (perf_evlist__mmap_ex(evlist, opts->mmap_pages, false,
> + opts->auxtrace_mmap_pages,
> + opts->auxtrace_snapshot_mode) < 0) {
> + if (errno == EPERM) {
> + pr_err("Permission error mapping pages.\n"
> + "Consider increasing "
> + "/proc/sys/kernel/perf_event_mlock_kb,\n"
> + "or try again with a smaller value of -m/--mmap_pages.\n"
> + "(current value: %u,%u)\n",
> + opts->mmap_pages, opts->auxtrace_mmap_pages);
> + return -errno;
> + } else {
> + pr_err("failed to mmap with %d (%s)\n", errno,
> + strerror_r(errno, msg, sizeof(msg)));
> + if (errno)
> + return -errno;
> + else
> + return -EINVAL;
> + }
> + }
> + return 0;
> +}
> +
> +static int record__mmap(struct record *rec)
> +{
> + return record__mmap_evlist(rec, rec->evlist);
> +}
> +
> static int record__open(struct record *rec)
> {
> char msg[512];
> @@ -378,27 +412,9 @@ try_again:
> goto out;
> }
>
> - if (perf_evlist__mmap_ex(evlist, opts->mmap_pages, false,
> - opts->auxtrace_mmap_pages,
> - opts->auxtrace_snapshot_mode) < 0) {
> - if (errno == EPERM) {
> - pr_err("Permission error mapping pages.\n"
> - "Consider increasing "
> - "/proc/sys/kernel/perf_event_mlock_kb,\n"
> - "or try again with a smaller value of -m/--mmap_pages.\n"
> - "(current value: %u,%u)\n",
> - opts->mmap_pages, opts->auxtrace_mmap_pages);
> - rc = -errno;
> - } else {
> - pr_err("failed to mmap with %d (%s)\n", errno,
> - strerror_r(errno, msg, sizeof(msg)));
> - if (errno)
> - rc = -errno;
> - else
> - rc = -EINVAL;
> - }
> + rc = record__mmap(rec);
> + if (rc)
> goto out;
> - }
>
> session->evlist = evlist;
> perf_session__set_id_hdr_size(session);
> --
> 1.8.3.4