commit d07d17adab5b918bd0543ce78f75a4747a057379
Author: Jens Axboe <axboe@kernel.dk>
Date:   Wed Mar 9 19:31:57 2022 -0700

    test/wakeup-ring: add test cases for IORING_OP_WAKEUP_RING
    
    Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/.gitignore b/.gitignore
index c9dc77fbe162..961fd9e96dc7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -128,6 +128,7 @@
 /test/timeout-overflow
 /test/unlink
 /test/wakeup-hang
+/test/wakeup-ring
 /test/multicqes_drain
 /test/poll-mshot-update
 /test/rsrc_tags
diff --git a/src/include/liburing/io_uring.h b/src/include/liburing/io_uring.h
index a7d193d0df38..8f919b42a8ea 100644
--- a/src/include/liburing/io_uring.h
+++ b/src/include/liburing/io_uring.h
@@ -147,6 +147,7 @@ enum {
 	IORING_OP_MKDIRAT,
 	IORING_OP_SYMLINKAT,
 	IORING_OP_LINKAT,
+	IORING_OP_WAKEUP_RING,
 
 	/* this goes last, obviously */
 	IORING_OP_LAST,
diff --git a/test/Makefile b/test/Makefile
index f421f536df87..4aafbae826ca 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -151,6 +151,7 @@ test_srcs := \
 	timeout-overflow.c \
 	unlink.c \
 	wakeup-hang.c \
+	wakeup-ring.c \
 	skip-cqe.c \
 	# EOL
 
@@ -221,6 +222,7 @@ ring-leak2: override LDFLAGS += -lpthread
 poll-mshot-update: override LDFLAGS += -lpthread
 exit-no-cleanup: override LDFLAGS += -lpthread
 pollfree: override LDFLAGS += -lpthread
+wakeup-ring: override LDFLAGS += -lpthread
 
 install: $(test_targets) runtests.sh runtests-loop.sh
 	$(INSTALL) -D -d -m 755 $(datadir)/liburing-test/
diff --git a/test/wakeup-ring.c b/test/wakeup-ring.c
new file mode 100644
index 000000000000..0ccae92d4c93
--- /dev/null
+++ b/test/wakeup-ring.c
@@ -0,0 +1,172 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Description: test ring wakeup command
+ *
+ */
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <pthread.h>
+
+#include "liburing.h"
+
+static int no_wakeup;
+
+static int test_own(struct io_uring *ring)
+{
+	struct io_uring_cqe *cqe;
+	struct io_uring_sqe *sqe;
+	int ret, i;
+
+	sqe = io_uring_get_sqe(ring);
+	if (!sqe) {
+		fprintf(stderr, "get sqe failed\n");
+		goto err;
+	}
+
+	sqe->opcode = IORING_OP_WAKEUP_RING;
+	sqe->fd = ring->ring_fd;
+	sqe->user_data = 1;
+
+	ret = io_uring_submit(ring);
+	if (ret <= 0) {
+		fprintf(stderr, "sqe submit failed: %d\n", ret);
+		goto err;
+	}
+
+	for (i = 0; i < 2; i++) {
+		ret = io_uring_peek_cqe(ring, &cqe);
+		if (ret < 0) {
+			fprintf(stderr, "wait completion %d\n", ret);
+			goto err;
+		}
+		switch (cqe->user_data) {
+		case 1:
+			if (cqe->res == -EINVAL || cqe->res == -EOPNOTSUPP) {
+				no_wakeup = 1;
+				return 0;
+			}
+			if (cqe->res != 0) {
+				fprintf(stderr, "wakeup res %d\n", cqe->res);
+				return -1;
+			}
+			break;
+		case 0:
+			if (!(cqe->flags & (1U << 2))) {
+				fprintf(stderr, "invalid flags %x\n", cqe->flags);
+				return -1;
+			}
+			break;
+		}
+		io_uring_cqe_seen(ring, cqe);
+	}
+
+	return 0;
+err:
+	return 1;
+}
+
+static void *wait_cqe_fn(void *data)
+{
+	struct io_uring *ring = data;
+	struct io_uring_cqe *cqe;
+	int ret;
+
+	ret = io_uring_wait_cqe(ring, &cqe);
+	if (ret) {
+		fprintf(stderr, "wait cqe %d\n", ret);
+		goto err;
+	}
+
+	if (!(cqe->flags & (1U << 2))) {
+		fprintf(stderr, "invalid flags %x\n", cqe->flags);
+		goto err;
+	}
+
+	return NULL;
+err:
+	return (void *) (unsigned long) 1;
+}
+
+static int test_remote(struct io_uring *ring, struct io_uring *target)
+{
+	struct io_uring_cqe *cqe;
+	struct io_uring_sqe *sqe;
+	int ret;
+
+	sqe = io_uring_get_sqe(ring);
+	if (!sqe) {
+		fprintf(stderr, "get sqe failed\n");
+		goto err;
+	}
+
+	sqe->opcode = IORING_OP_WAKEUP_RING;
+	sqe->fd = target->ring_fd;
+	sqe->user_data = 1;
+
+	ret = io_uring_submit(ring);
+	if (ret <= 0) {
+		fprintf(stderr, "sqe submit failed: %d\n", ret);
+		goto err;
+	}
+
+	ret = io_uring_peek_cqe(ring, &cqe);
+	if (ret < 0) {
+		fprintf(stderr, "wait completion %d\n", ret);
+		goto err;
+	}
+	if (cqe->res != 0) {
+		fprintf(stderr, "wakeup res %d\n", cqe->res);
+		return -1;
+	}
+
+	io_uring_cqe_seen(ring, cqe);
+	return 0;
+err:
+	return 1;
+}
+
+int main(int argc, char *argv[])
+{
+	struct io_uring ring, ring2;
+	pthread_t thread;
+	void *tret;
+	int ret;
+
+	if (argc > 1)
+		return 0;
+
+	ret = io_uring_queue_init(8, &ring, 0);
+	if (ret) {
+		fprintf(stderr, "ring setup failed: %d\n", ret);
+		return 1;
+	}
+	ret = io_uring_queue_init(8, &ring2, 0);
+	if (ret) {
+		fprintf(stderr, "ring setup failed: %d\n", ret);
+		return 1;
+	}
+
+	pthread_create(&thread, NULL, wait_cqe_fn, &ring2);
+
+	ret = test_own(&ring);
+	if (ret) {
+		fprintf(stderr, "test_own failed\n");
+		return ret;
+	}
+	if (no_wakeup)
+		return 0;
+
+	ret = test_remote(&ring, &ring2);
+	if (ret) {
+		fprintf(stderr, "test_remote failed\n");
+		return ret;
+	}
+
+	pthread_join(thread, &tret);
+
+	return 0;
+}