[PATCH liburing 0/2] add zcrx example

[PATCH liburing 0/2] add zcrx example

[Pavel Begunkov]

We need a simple example for zcrx to show case how the api works
and how to use features. Take the selftest and strip it off tx.

Anything supporting tcp can play a role of the sender, but for
data verification (-v) it needs to follow the data pattern.
Implement it in send-zerocopy -z0.

Pavel Begunkov (2):
  examples/send-zerocopy: add data verification
  examples: add a zcrx example

 examples/Makefile        |   1 +
 examples/send-zerocopy.c |  50 +++++-
 examples/zcrx.c          | 362 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 410 insertions(+), 3 deletions(-)
 create mode 100644 examples/zcrx.c

-- 
2.48.1

[PATCH liburing 1/2] examples/send-zerocopy: add data verification

[Pavel Begunkov]

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 examples/send-zerocopy.c | 50 +++++++++++++++++++++++++++++++++++++---
 1 file changed, 47 insertions(+), 3 deletions(-)

diff --git a/examples/send-zerocopy.c b/examples/send-zerocopy.c
index a50896c6..b0f2a76a 100644
--- a/examples/send-zerocopy.c
+++ b/examples/send-zerocopy.c
@@ -58,6 +58,13 @@ struct thread_data {
 	int fd;
 };
 
+enum {
+	VERIFY_DISABLED = 0,
+	VERIFY_SEQ,
+
+	__MAX_VERIFY,
+};
+
 static bool cfg_reg_ringfd = true;
 static bool cfg_fixed_files = 1;
 static bool cfg_zc = 1;
@@ -74,8 +81,8 @@ static int  cfg_type		= 0;
 static int  cfg_payload_len;
 static int  cfg_port		= 8000;
 static int  cfg_runtime_ms	= 4200;
+static int  cfg_verify		= 0;
 static bool cfg_rx_poll		= false;
-
 static socklen_t cfg_alen;
 static char *str_addr = NULL;
 
@@ -198,13 +205,30 @@ static int do_poll(int fd, int events)
 	return ret && (pfd.revents & events);
 }
 
+static void verify_buffer(struct thread_data *td, char *buffer, size_t size)
+{
+	size_t i;
+
+	for (i = 0; i < size; i++) {
+		char d = payload[i];
+		char e = (td->bytes + i) % 26 + 'a';
+
+		if (e != d)
+			t_error(1, -EINVAL, "data mismatch");
+	}
+}
+
 /* Flush all outstanding bytes for the tcp receive queue */
 static int do_flush_tcp(struct thread_data *td, int fd)
 {
 	int ret;
 
+	if (cfg_verify == VERIFY_SEQ)
+		ret = recv(fd, payload_buf, sizeof(payload_buf), 0);
+	else
+		ret = recv(fd, NULL, 1 << 21, MSG_TRUNC | MSG_DONTWAIT);
+
 	/* MSG_TRUNC flushes up to len bytes */
-	ret = recv(fd, NULL, 1 << 21, MSG_TRUNC | MSG_DONTWAIT);
 	if (ret == -1 && errno == EAGAIN)
 		return 0;
 	if (ret == -1)
@@ -212,6 +236,9 @@ static int do_flush_tcp(struct thread_data *td, int fd)
 	if (!ret)
 		return 1;
 
+	if (cfg_verify == VERIFY_SEQ)
+		verify_buffer(td, payload_buf, ret);
+
 	td->packets++;
 	td->bytes += ret;
 	return 0;
@@ -391,6 +418,11 @@ static void do_tx(struct thread_data *td, int domain, int type, int protocol)
 		unsigned buf_idx = 0;
 		unsigned msg_flags = MSG_WAITALL;
 
+		if (cfg_verify) {
+			for (i = 0; i < cfg_payload_len; i++)
+				payload[i] = 'a' + ((i + td->bytes) % 26);
+		}
+
 		for (i = 0; i < cfg_nr_reqs; i++) {
 			sqe = io_uring_get_sqe(&ring);
 
@@ -515,7 +547,7 @@ static void parse_opts(int argc, char **argv)
 
 	cfg_payload_len = max_payload_len;
 
-	while ((c = getopt(argc, argv, "46D:p:s:t:n:z:b:l:dC:T:Ry")) != -1) {
+	while ((c = getopt(argc, argv, "46v:D:p:s:t:n:z:b:l:dC:T:Ry")) != -1) {
 		switch (c) {
 		case '4':
 			if (cfg_family != PF_UNSPEC)
@@ -570,9 +602,21 @@ static void parse_opts(int argc, char **argv)
 		case 'y':
 			cfg_rx_poll = 1;
 			break;
+		case 'v':
+			cfg_verify = strtoul(optarg, NULL, 0);
+			break;
 		}
 	}
 
+	if (cfg_verify >= __MAX_VERIFY)
+		t_error(1, 0, "unsupported data verification type");
+	if (cfg_verify) {
+		if (!cfg_rx && cfg_zc)
+			t_error(1, 0, "verification doesn't work with sendzc");
+		if (cfg_verify == VERIFY_SEQ && cfg_nr_reqs > 1 && !cfg_zc)
+			t_error(1, 0, "sequence verification invalid inflight number");
+	}
+
 	if (cfg_nr_reqs > MAX_SUBMIT_NR)
 		t_error(1, 0, "-n: submit batch nr exceeds max (%d)", MAX_SUBMIT_NR);
 	if (cfg_payload_len > max_payload_len)
-- 
2.48.1

[PATCH liburing 2/2] examples: add a zcrx example

[Pavel Begunkov]

Copy-pasted from selftests/.../iou_zcrx.c by David.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 examples/Makefile |   1 +
 examples/zcrx.c   | 362 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 363 insertions(+)
 create mode 100644 examples/zcrx.c

diff --git a/examples/Makefile b/examples/Makefile
index 7b740ca9..47bdfbf3 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -32,6 +32,7 @@ example_srcs := \
 	send-zerocopy.c \
 	rsrc-update-bench.c \
 	proxy.c \
+	zcrx.c \
 	kdigest.c
 
 all_targets :=
diff --git a/examples/zcrx.c b/examples/zcrx.c
new file mode 100644
index 00000000..2ac8af52
--- /dev/null
+++ b/examples/zcrx.c
@@ -0,0 +1,362 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <assert.h>
+#include <errno.h>
+#include <error.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdarg.h>
+
+#include <arpa/inet.h>
+#include <linux/errqueue.h>
+#include <linux/if_packet.h>
+#include <linux/ipv6.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <net/ethernet.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/tcp.h>
+#include <netinet/udp.h>
+#include <sys/epoll.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <sys/wait.h>
+
+#include "liburing.h"
+
+static void t_error(int status, int errnum, const char *format, ...)
+{
+	va_list args;
+	va_start(args, format);
+
+	vfprintf(stderr, format, args);
+	if (errnum)
+		fprintf(stderr, ": %s", strerror(errnum));
+
+	fprintf(stderr, "\n");
+	va_end(args);
+	exit(status);
+}
+
+#define PAGE_SIZE (4096)
+#define AREA_SIZE (8192 * PAGE_SIZE)
+#define SEND_SIZE (512 * 4096)
+#define min(a, b) \
+	({ \
+		typeof(a) _a = (a); \
+		typeof(b) _b = (b); \
+		_a < _b ? _a : _b; \
+	})
+#define min_t(t, a, b) \
+	({ \
+		t _ta = (a); \
+		t _tb = (b); \
+		min(_ta, _tb); \
+	})
+
+#define ALIGN_UP(v, align) (((v) + (align) - 1) & ~((align) - 1))
+
+static int cfg_port = 8000;
+static const char *cfg_ifname;
+static int cfg_queue_id = -1;
+static bool cfg_oneshot;
+static int cfg_oneshot_recvs;
+static bool cfg_verify_data = false;
+static struct sockaddr_in6 cfg_addr;
+
+static void *area_ptr;
+static void *ring_ptr;
+static size_t ring_size;
+static struct io_uring_zcrx_rq rq_ring;
+static unsigned long area_token;
+static int connfd;
+static bool stop;
+static size_t received;
+
+static inline size_t get_refill_ring_size(unsigned int rq_entries)
+{
+	ring_size = rq_entries * sizeof(struct io_uring_zcrx_rqe);
+	/* add space for the header (head/tail/etc.) */
+	ring_size += PAGE_SIZE;
+	return ALIGN_UP(ring_size, 4096);
+}
+
+static void setup_zcrx(struct io_uring *ring)
+{
+	unsigned int ifindex;
+	unsigned int rq_entries = 4096;
+	int ret;
+
+	ifindex = if_nametoindex(cfg_ifname);
+	if (!ifindex)
+		t_error(1, 0, "bad interface name: %s", cfg_ifname);
+
+	area_ptr = mmap(NULL,
+			AREA_SIZE,
+			PROT_READ | PROT_WRITE,
+			MAP_ANONYMOUS | MAP_PRIVATE,
+			0,
+			0);
+	if (area_ptr == MAP_FAILED)
+		t_error(1, 0, "mmap(): zero copy area");
+
+	ring_size = get_refill_ring_size(rq_entries);
+	ring_ptr = mmap(NULL,
+			ring_size,
+			PROT_READ | PROT_WRITE,
+			MAP_ANONYMOUS | MAP_PRIVATE,
+			0,
+			0);
+
+	struct io_uring_region_desc region_reg = {
+		.size = ring_size,
+		.user_addr = (__u64)(unsigned long)ring_ptr,
+		.flags = IORING_MEM_REGION_TYPE_USER,
+	};
+
+	struct io_uring_zcrx_area_reg area_reg = {
+		.addr = (__u64)(unsigned long)area_ptr,
+		.len = AREA_SIZE,
+		.flags = 0,
+	};
+
+	struct io_uring_zcrx_ifq_reg reg = {
+		.if_idx = ifindex,
+		.if_rxq = cfg_queue_id,
+		.rq_entries = rq_entries,
+		.area_ptr = (__u64)(unsigned long)&area_reg,
+		.region_ptr = (__u64)(unsigned long)&region_reg,
+	};
+
+	ret = io_uring_register_ifq(ring, &reg);
+	if (ret)
+		t_error(1, 0, "io_uring_register_ifq(): %d", ret);
+
+	rq_ring.khead = (unsigned int *)((char *)ring_ptr + reg.offsets.head);
+	rq_ring.ktail = (unsigned int *)((char *)ring_ptr + reg.offsets.tail);
+	rq_ring.rqes = (struct io_uring_zcrx_rqe *)((char *)ring_ptr + reg.offsets.rqes);
+	rq_ring.rq_tail = 0;
+	rq_ring.ring_entries = reg.rq_entries;
+
+	area_token = area_reg.rq_area_token;
+}
+
+static void add_accept(struct io_uring *ring, int sockfd)
+{
+	struct io_uring_sqe *sqe;
+
+	sqe = io_uring_get_sqe(ring);
+
+	io_uring_prep_accept(sqe, sockfd, NULL, NULL, 0);
+	sqe->user_data = 1;
+}
+
+static void add_recvzc(struct io_uring *ring, int sockfd)
+{
+	struct io_uring_sqe *sqe;
+
+	sqe = io_uring_get_sqe(ring);
+
+	io_uring_prep_rw(IORING_OP_RECV_ZC, sqe, sockfd, NULL, 0, 0);
+	sqe->ioprio |= IORING_RECV_MULTISHOT;
+	sqe->user_data = 2;
+}
+
+static void add_recvzc_oneshot(struct io_uring *ring, int sockfd, size_t len)
+{
+	struct io_uring_sqe *sqe;
+
+	sqe = io_uring_get_sqe(ring);
+
+	io_uring_prep_rw(IORING_OP_RECV_ZC, sqe, sockfd, NULL, len, 0);
+	sqe->ioprio |= IORING_RECV_MULTISHOT;
+	sqe->user_data = 2;
+}
+
+static void process_accept(struct io_uring *ring, struct io_uring_cqe *cqe)
+{
+	if (cqe->res < 0)
+		t_error(1, 0, "accept()");
+	if (connfd)
+		t_error(1, 0, "Unexpected second connection");
+
+	connfd = cqe->res;
+	if (cfg_oneshot)
+		add_recvzc_oneshot(ring, connfd, PAGE_SIZE);
+	else
+		add_recvzc(ring, connfd);
+}
+
+static void verify_data(char *data, size_t size, unsigned long seq)
+{
+	int i;
+
+	if (!cfg_verify_data)
+		return;
+
+	for (i = 0; i < size; i++) {
+		char expected = 'a' + (received + i) % 26;
+
+		if (data[i] != expected)
+			t_error(1, 0, "payload mismatch at %i", i);
+	}
+}
+
+static void process_recvzc(struct io_uring *ring, struct io_uring_cqe *cqe)
+{
+	unsigned rq_mask = rq_ring.ring_entries - 1;
+	struct io_uring_zcrx_cqe *rcqe;
+	struct io_uring_zcrx_rqe *rqe;
+	uint64_t mask;
+	char *data;
+
+	if (cqe->res == 0 && cqe->flags == 0 && cfg_oneshot_recvs == 0) {
+		stop = true;
+		return;
+	}
+
+	if (cqe->res < 0)
+		t_error(1, 0, "recvzc(): %d", cqe->res);
+
+	if (cfg_oneshot) {
+		if (cqe->res == 0 && cqe->flags == 0 && cfg_oneshot_recvs) {
+			add_recvzc_oneshot(ring, connfd, PAGE_SIZE);
+			cfg_oneshot_recvs--;
+		}
+	} else if (!(cqe->flags & IORING_CQE_F_MORE)) {
+		add_recvzc(ring, connfd);
+	}
+
+	rcqe = (struct io_uring_zcrx_cqe *)(cqe + 1);
+	mask = (1ULL << IORING_ZCRX_AREA_SHIFT) - 1;
+	data = (char *)area_ptr + (rcqe->off & mask);
+
+	verify_data(data, cqe->res, received);
+	received += cqe->res;
+
+	/* processed, return back to the kernel */
+	rqe = &rq_ring.rqes[rq_ring.rq_tail & rq_mask];
+	rqe->off = (rcqe->off & ~IORING_ZCRX_AREA_MASK) | area_token;
+	rqe->len = cqe->res;
+	io_uring_smp_store_release(rq_ring.ktail, ++rq_ring.rq_tail);
+}
+
+static void server_loop(struct io_uring *ring)
+{
+	struct io_uring_cqe *cqe;
+	unsigned int head, count = 0;
+
+	io_uring_submit_and_wait(ring, 1);
+
+	io_uring_for_each_cqe(ring, head, cqe) {
+		if (cqe->user_data == 1)
+			process_accept(ring, cqe);
+		else if (cqe->user_data == 2)
+			process_recvzc(ring, cqe);
+		else
+			t_error(1, 0, "unknown cqe");
+		count++;
+	}
+	io_uring_cq_advance(ring, count);
+}
+
+static void run_server(void)
+{
+	unsigned int flags = 0;
+	struct io_uring ring;
+	int fd, enable, ret;
+
+	fd = socket(AF_INET6, SOCK_STREAM, 0);
+	if (fd == -1)
+		t_error(1, 0, "socket()");
+
+	enable = 1;
+	ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(int));
+	if (ret < 0)
+		t_error(1, 0, "setsockopt(SO_REUSEADDR)");
+
+	ret = bind(fd, (struct sockaddr *)&cfg_addr, sizeof(cfg_addr));
+	if (ret < 0)
+		t_error(1, 0, "bind()");
+
+	if (listen(fd, 1024) < 0)
+		t_error(1, 0, "listen()");
+
+	flags |= IORING_SETUP_COOP_TASKRUN;
+	flags |= IORING_SETUP_SINGLE_ISSUER;
+	flags |= IORING_SETUP_DEFER_TASKRUN;
+	flags |= IORING_SETUP_SUBMIT_ALL;
+	flags |= IORING_SETUP_CQE32;
+
+	ret = io_uring_queue_init(512, &ring, flags);
+	if (ret)
+		t_error(1, ret, "ring init failed");
+
+	setup_zcrx(&ring);
+	add_accept(&ring, fd);
+
+	while (!stop)
+		server_loop(&ring);
+}
+
+static void usage(const char *filepath)
+{
+	t_error(1, 0, "Usage: %s (-4|-6) -p<port> -i<ifname> -q<rxq_id>", filepath);
+}
+
+static void parse_opts(int argc, char **argv)
+{
+	struct sockaddr_in6 *addr6 = (void *) &cfg_addr;
+	int c;
+
+	if (argc <= 1)
+		usage(argv[0]);
+
+	while ((c = getopt(argc, argv, "vp:i:q:o:")) != -1) {
+		switch (c) {
+		case 'p':
+			cfg_port = strtoul(optarg, NULL, 0);
+			break;
+		case 'i':
+			cfg_ifname = optarg;
+			break;
+		case 'o': {
+			cfg_oneshot = true;
+			cfg_oneshot_recvs = strtoul(optarg, NULL, 0);
+			break;
+		}
+		case 'q':
+			cfg_queue_id = strtoul(optarg, NULL, 0);
+			break;
+		}
+		case 'v':
+			cfg_verify_data = true;
+			break;
+	}
+
+	memset(addr6, 0, sizeof(*addr6));
+	addr6->sin6_family = AF_INET6;
+	addr6->sin6_port = htons(cfg_port);
+	addr6->sin6_addr = in6addr_any;
+}
+
+int main(int argc, char **argv)
+{
+	parse_opts(argc, argv);
+	run_server();
+	return 0;
+}
-- 
2.48.1

Re: [PATCH liburing 2/2] examples: add a zcrx example

[Pavel Begunkov]

On 4/9/25 18:58, Pavel Begunkov wrote:
...
> +static void parse_opts(int argc, char **argv)
> +{
> +	struct sockaddr_in6 *addr6 = (void *) &cfg_addr;
> +	int c;
> +
> +	if (argc <= 1)
> +		usage(argv[0]);
> +
> +	while ((c = getopt(argc, argv, "vp:i:q:o:")) != -1) {
> +		switch (c) {
> +		case 'p':
> +			cfg_port = strtoul(optarg, NULL, 0);
> +			break;
> +		case 'i':
> +			cfg_ifname = optarg;
> +			break;
> +		case 'o': {
> +			cfg_oneshot = true;
> +			cfg_oneshot_recvs = strtoul(optarg, NULL, 0);
> +			break;
> +		}
> +		case 'q':
> +			cfg_queue_id = strtoul(optarg, NULL, 0);
> +			break;
> +		}
> +		case 'v':
> +			cfg_verify_data = true;
> +			break;

Sth went wrong here, I'll need to resend.

-- 
Pavel Begunkov