Re: [PATCH v2 4/4] perf record: implement --affinity=node|cpu option

Jiri Olsa
2019-01-01T21:39:52Z

On Mon, Dec 24, 2018 at 03:28:33PM +0300, Alexey Budankov wrote:
>
> Implement --affinity=node|cpu option for the record mode defaulting
> to system affinity mask bouncing.
>
> Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
> ---
> tools/perf/Documentation/perf-record.txt | 5 +++++
> tools/perf/builtin-record.c | 18 ++++++++++++++++++
> 2 files changed, 23 insertions(+)
>
> diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
> index d232b13ea713..efb839784f32 100644
> --- a/tools/perf/Documentation/perf-record.txt
> +++ b/tools/perf/Documentation/perf-record.txt
> @@ -440,6 +440,11 @@ Use <n> control blocks in asynchronous (Posix AIO) trace writing mode (default:
> Asynchronous mode is supported only when linking Perf tool with libc library
> providing implementation for Posix AIO API.
>
> +--affinity=mode::
> +Set affinity mask of trace reading thread according to the policy defined by 'mode' value:
> + node - thread affinity mask is set to NUMA node cpu mask of the processed mmap buffer
> + cpu - thread affinity mask is set to cpu of the processed mmap buffer
> +
> --all-kernel::
> Configure all used events to run in kernel space.
>
> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> index eea96794ee45..57dc3a45d16f 100644
> --- a/tools/perf/builtin-record.c
> +++ b/tools/perf/builtin-record.c
> @@ -1653,6 +1653,21 @@ static int parse_clockid(const struct option *opt, const char *str, int unset)
> ui__warning("unknown clockid %s, check man page\n", ostr);
> return -1;
> }
> +static int record__parse_affinity(const struct option *opt, const char *str, int unset)
> +{
> + struct record_opts *opts = (struct record_opts *)opt->value;
> +

please use:

if (unset)
return 0;

if (str) {
...
}

jirka

> + if (!unset) {
> + if (str) {
> + if (!strcasecmp(str, "node"))
> + opts->affinity = PERF_AFFINITY_NODE;
> + else if (!strcasecmp(str, "cpu"))
> + opts->affinity = PERF_AFFINITY_CPU;
> + }
> + }
> +
> + return 0;
> +}
>
> static int record__parse_mmap_pages(const struct option *opt,
> const char *str,
> @@ -1961,6 +1976,9 @@ static struct option __record_options[] = {
> &nr_cblocks_default, "n", "Use <n> control blocks in asynchronous trace writing mode (default: 1, max: 4)",
> record__aio_parse),
> #endif
> + OPT_CALLBACK(0, "affinity", &record.opts, "node|cpu",
> + "Set affinity mask of trace reading thread to NUMA node cpu mask or cpu of processed mmap buffer",
> + record__parse_affinity),
> OPT_END()
> };