[PATCH v4 4/4] perf record: implement --affinity=node|cpu option

From: Alexey Budankov
Date: Thu Jan 10 2019 - 06:24:33 EST



Implement --affinity=node|cpu option for the record mode defaulting
to system affinity mask bouncing.

Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>
---
changes in v3:
- adjusted indentation at record__parse_affinity()
---
tools/perf/Documentation/perf-record.txt | 5 +++++
tools/perf/builtin-record.c | 20 ++++++++++++++++++++
2 files changed, 25 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 553c2fabf3c1..94a966ba9a6f 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1659,6 +1659,23 @@ static int parse_clockid(const struct option *opt, const char *str, int unset)
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;
+
+ if (unset)
+ return 0;
+
+ 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,
int unset __maybe_unused)
@@ -1966,6 +1983,9 @@ 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()
};