[PATCH bpf-next] libbpf: Add '_wait()' and '_nowait()' macros for 'bpf_ring_buffer__poll()'

[Pedro Tammela <pctammela@gmail.com>]

'bpf_ring_buffer__poll()' abstracts the polling method, so abstract the
constants that make the implementation don't wait or wait indefinetly
for data.

Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
---
 tools/lib/bpf/libbpf.h                                 | 3 +++
 tools/testing/selftests/bpf/benchs/bench_ringbufs.c    | 2 +-
 tools/testing/selftests/bpf/prog_tests/ringbuf.c       | 6 +++---
 tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c | 4 ++--
 4 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index f500621d28e5..3817d84f91c6 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -540,6 +540,9 @@ LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms);
 LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb);
 LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb);
 
+#define ring_buffer__poll_wait(rb) ring_buffer__poll(rb, -1)
+#define ring_buffer__poll_nowait(rb) ring_buffer__poll(rb, 0)
+
 /* Perf buffer APIs */
 struct perf_buffer;
 
diff --git a/tools/testing/selftests/bpf/benchs/bench_ringbufs.c b/tools/testing/selftests/bpf/benchs/bench_ringbufs.c
index bde6c9d4cbd4..82db2cc9bab3 100644
--- a/tools/testing/selftests/bpf/benchs/bench_ringbufs.c
+++ b/tools/testing/selftests/bpf/benchs/bench_ringbufs.c
@@ -191,7 +191,7 @@ static void *ringbuf_libbpf_consumer(void *input)
 {
 	struct ringbuf_libbpf_ctx *ctx = &ringbuf_libbpf_ctx;
 
-	while (ring_buffer__poll(ctx->ringbuf, -1) >= 0) {
+	while (ring_buffer__poll_wait(ctx->ringbuf) >= 0) {
 		if (args.back2back)
 			bufs_trigger_batch();
 	}
diff --git a/tools/testing/selftests/bpf/prog_tests/ringbuf.c b/tools/testing/selftests/bpf/prog_tests/ringbuf.c
index fddbc5db5d6a..321c646a0685 100644
--- a/tools/testing/selftests/bpf/prog_tests/ringbuf.c
+++ b/tools/testing/selftests/bpf/prog_tests/ringbuf.c
@@ -121,7 +121,7 @@ void test_ringbuf(void)
 	      3L * rec_sz, skel->bss->prod_pos);
 
 	/* poll for samples */
-	err = ring_buffer__poll(ringbuf, -1);
+	err = ring_buffer__poll_wait(ringbuf);
 
 	/* -EDONE is used as an indicator that we are done */
 	if (CHECK(err != -EDONE, "err_done", "done err: %d\n", err))
@@ -130,7 +130,7 @@ void test_ringbuf(void)
 	CHECK(cnt != 2, "cnt", "exp %d samples, got %d\n", 2, cnt);
 
 	/* we expect extra polling to return nothing */
-	err = ring_buffer__poll(ringbuf, 0);
+	err = ring_buffer__poll_nowait(ringbuf);
 	if (CHECK(err != 0, "extra_samples", "poll result: %d\n", err))
 		goto cleanup;
 	cnt = atomic_xchg(&sample_cnt, 0);
@@ -148,7 +148,7 @@ void test_ringbuf(void)
 	CHECK(skel->bss->cons_pos != 3 * rec_sz,
 	      "err_cons_pos", "exp %ld, got %ld\n",
 	      3L * rec_sz, skel->bss->cons_pos);
-	err = ring_buffer__poll(ringbuf, -1);
+	err = ring_buffer__poll_wait(ringbuf);
 	CHECK(err <= 0, "poll_err", "err %d\n", err);
 	cnt = atomic_xchg(&sample_cnt, 0);
 	CHECK(cnt != 2, "cnt", "exp %d samples, got %d\n", 2, cnt);
diff --git a/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c b/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
index d37161e59bb2..65ba0a3472f1 100644
--- a/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/ringbuf_multi.c
@@ -80,12 +80,12 @@ void test_ringbuf_multi(void)
 	syscall(__NR_getpgid);
 
 	/* poll for samples, should get 2 ringbufs back */
-	err = ring_buffer__poll(ringbuf, -1);
+	err = ring_buffer__poll_wait(ringbuf);
 	if (CHECK(err != 2, "poll_res", "expected 2 records, got %d\n", err))
 		goto cleanup;
 
 	/* expect extra polling to return nothing */
-	err = ring_buffer__poll(ringbuf, 0);
+	err = ring_buffer__poll_nowait(ringbuf);
 	if (CHECK(err < 0, "extra_samples", "poll result: %d\n", err))
 		goto cleanup;
 
-- 
2.25.1