[PATCH v4 06/10] selftests/net: Extract uring helpers to be reusable

Breno Leitao
2023-09-04T16:25:48Z

Instead of defining basic io_uring functions in the test case, move them
to a common directory, so, other tests can use them.

This simplify the test code and reuse the common liburing
infrastructure. This is basically a copy of what we have in
io_uring_zerocopy_tx with some minor improvements to make checkpatch
happy.

A follow-up test will use the same helpers in a BPF sockopt test.

Signed-off-by: Breno Leitao <leitao@debian.org>
---
tools/include/io_uring/mini_liburing.h | 282 ++++++++++++++++++
tools/testing/selftests/net/Makefile | 1 +
.../selftests/net/io_uring_zerocopy_tx.c | 268 +----------------
3 files changed, 285 insertions(+), 266 deletions(-)
create mode 100644 tools/include/io_uring/mini_liburing.h

diff --git a/tools/include/io_uring/mini_liburing.h b/tools/include/io_uring/mini_liburing.h
new file mode 100644
index 000000000000..9ccb16074eb5
--- /dev/null
+++ b/tools/include/io_uring/mini_liburing.h
@@ -0,0 +1,282 @@
+/* SPDX-License-Identifier: MIT */
+
+#include <linux/io_uring.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+struct io_sq_ring {
+ unsigned int *head;
+ unsigned int *tail;
+ unsigned int *ring_mask;
+ unsigned int *ring_entries;
+ unsigned int *flags;
+ unsigned int *array;
+};
+
+struct io_cq_ring {
+ unsigned int *head;
+ unsigned int *tail;
+ unsigned int *ring_mask;
+ unsigned int *ring_entries;
+ struct io_uring_cqe *cqes;
+};
+
+struct io_uring_sq {
+ unsigned int *khead;
+ unsigned int *ktail;
+ unsigned int *kring_mask;
+ unsigned int *kring_entries;
+ unsigned int *kflags;
+ unsigned int *kdropped;
+ unsigned int *array;
+ struct io_uring_sqe *sqes;
+
+ unsigned int sqe_head;
+ unsigned int sqe_tail;
+
+ size_t ring_sz;
+};
+
+struct io_uring_cq {
+ unsigned int *khead;
+ unsigned int *ktail;
+ unsigned int *kring_mask;
+ unsigned int *kring_entries;
+ unsigned int *koverflow;
+ struct io_uring_cqe *cqes;
+
+ size_t ring_sz;
+};
+
+struct io_uring {
+ struct io_uring_sq sq;
+ struct io_uring_cq cq;
+ int ring_fd;
+};
+
+#if defined(__x86_64) || defined(__i386__)
+#define read_barrier() __asm__ __volatile__("":::"memory")
+#define write_barrier() __asm__ __volatile__("":::"memory")
+#else
+#define read_barrier() __sync_synchronize()
+#define write_barrier() __sync_synchronize()
+#endif
+
+static inline int io_uring_mmap(int fd, struct io_uring_params *p,
+ struct io_uring_sq *sq, struct io_uring_cq *cq)
+{
+ size_t size;
+ void *ptr;
+ int ret;
+
+ sq->ring_sz = p->sq_off.array + p->sq_entries * sizeof(unsigned int);
+ ptr = mmap(0, sq->ring_sz, PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQ_RING);
+ if (ptr == MAP_FAILED)
+ return -errno;
+ sq->khead = ptr + p->sq_off.head;
+ sq->ktail = ptr + p->sq_off.tail;
+ sq->kring_mask = ptr + p->sq_off.ring_mask;
+ sq->kring_entries = ptr + p->sq_off.ring_entries;
+ sq->kflags = ptr + p->sq_off.flags;
+ sq->kdropped = ptr + p->sq_off.dropped;
+ sq->array = ptr + p->sq_off.array;
+
+ size = p->sq_entries * sizeof(struct io_uring_sqe);
+ sq->sqes = mmap(0, size, PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQES);
+ if (sq->sqes == MAP_FAILED) {
+ ret = -errno;
+err:
+ munmap(sq->khead, sq->ring_sz);
+ return ret;
+ }
+
+ cq->ring_sz = p->cq_off.cqes + p->cq_entries * sizeof(struct io_uring_cqe);
+ ptr = mmap(0, cq->ring_sz, PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_CQ_RING);
+ if (ptr == MAP_FAILED) {
+ ret = -errno;
+ munmap(sq->sqes, p->sq_entries * sizeof(struct io_uring_sqe));
+ goto err;
+ }
+ cq->khead = ptr + p->cq_off.head;
+ cq->ktail = ptr + p->cq_off.tail;
+ cq->kring_mask = ptr + p->cq_off.ring_mask;
+ cq->kring_entries = ptr + p->cq_off.ring_entries;
+ cq->koverflow = ptr + p->cq_off.overflow;
+ cq->cqes = ptr + p->cq_off.cqes;
+ return 0;
+}
+
+static inline int io_uring_setup(unsigned int entries,
+ struct io_uring_params *p)
+{
+ return syscall(__NR_io_uring_setup, entries, p);
+}
+
+static inline int io_uring_enter(int fd, unsigned int to_submit,
+ unsigned int min_complete,
+ unsigned int flags, sigset_t *sig)
+{
+ return syscall(__NR_io_uring_enter, fd, to_submit, min_complete,
+ flags, sig, _NSIG / 8);
+}
+
+static inline int io_uring_queue_init(unsigned int entries,
+ struct io_uring *ring,
+ unsigned int flags)
+{
+ struct io_uring_params p;
+ int fd, ret;
+
+ memset(ring, 0, sizeof(*ring));
+ memset(&p, 0, sizeof(p));
+ p.flags = flags;
+
+ fd = io_uring_setup(entries, &p);
+ if (fd < 0)
+ return fd;
+ ret = io_uring_mmap(fd, &p, &ring->sq, &ring->cq);
+ if (!ret)
+ ring->ring_fd = fd;
+ else
+ close(fd);
+ return ret;
+}
+
+/* Get a sqe */
+static inline struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring)
+{
+ struct io_uring_sq *sq = &ring->sq;
+
+ if (sq->sqe_tail + 1 - sq->sqe_head > *sq->kring_entries)
+ return NULL;
+ return &sq->sqes[sq->sqe_tail++ & *sq->kring_mask];
+}
+
+static inline int io_uring_wait_cqe(struct io_uring *ring,
+ struct io_uring_cqe **cqe_ptr)
+{
+ struct io_uring_cq *cq = &ring->cq;
+ const unsigned int mask = *cq->kring_mask;
+ unsigned int head = *cq->khead;
+ int ret;
+
+ *cqe_ptr = NULL;
+ do {
+ read_barrier();
+ if (head != *cq->ktail) {
+ *cqe_ptr = &cq->cqes[head & mask];
+ break;
+ }
+ ret = io_uring_enter(ring->ring_fd, 0, 1,
+ IORING_ENTER_GETEVENTS, NULL);
+ if (ret < 0)
+ return -errno;
+ } while (1);
+
+ return 0;
+}
+
+static inline int io_uring_submit(struct io_uring *ring)
+{
+ struct io_uring_sq *sq = &ring->sq;
+ const unsigned int mask = *sq->kring_mask;
+ unsigned int ktail, submitted, to_submit;
+ int ret;
+
+ read_barrier();
+ if (*sq->khead != *sq->ktail) {
+ submitted = *sq->kring_entries;
+ goto submit;
+ }
+ if (sq->sqe_head == sq->sqe_tail)
+ return 0;
+
+ ktail = *sq->ktail;
+ to_submit = sq->sqe_tail - sq->sqe_head;
+ for (submitted = 0; submitted < to_submit; submitted++) {
+ read_barrier();
+ sq->array[ktail++ & mask] = sq->sqe_head++ & mask;
+ }
+ if (!submitted)
+ return 0;
+
+ if (*sq->ktail != ktail) {
+ write_barrier();
+ *sq->ktail = ktail;
+ write_barrier();
+ }
+submit:
+ ret = io_uring_enter(ring->ring_fd, submitted, 0,
+ IORING_ENTER_GETEVENTS, NULL);
+ return ret < 0 ? -errno : ret;
+}
+
+static inline void io_uring_queue_exit(struct io_uring *ring)
+{
+ struct io_uring_sq *sq = &ring->sq;
+
+ munmap(sq->sqes, *sq->kring_entries * sizeof(struct io_uring_sqe));
+ munmap(sq->khead, sq->ring_sz);
+ close(ring->ring_fd);
+}
+
+/* Prepare and send the SQE */
+static inline void io_uring_prep_cmd(struct io_uring_sqe *sqe, int op,
+ int sockfd,
+ int level, int optname,
+ const void *optval,
+ int optlen)
+{
+ memset(sqe, 0, sizeof(*sqe));
+ sqe->opcode = (__u8)IORING_OP_URING_CMD;
+ sqe->fd = sockfd;
+ sqe->cmd_op = op;
+
+ sqe->level = level;
+ sqe->optname = optname;
+ sqe->optval = (unsigned long long)optval;
+ sqe->optlen = optlen;
+}
+
+static inline int io_uring_register_buffers(struct io_uring *ring,
+ const struct iovec *iovecs,
+ unsigned int nr_iovecs)
+{
+ int ret;
+
+ ret = syscall(__NR_io_uring_register, ring->ring_fd,
+ IORING_REGISTER_BUFFERS, iovecs, nr_iovecs);
+ return (ret < 0) ? -errno : ret;
+}
+
+static inline void io_uring_prep_send(struct io_uring_sqe *sqe, int sockfd,
+ const void *buf, size_t len, int flags)
+{
+ memset(sqe, 0, sizeof(*sqe));
+ sqe->opcode = (__u8)IORING_OP_SEND;
+ sqe->fd = sockfd;
+ sqe->addr = (unsigned long)buf;
+ sqe->len = len;
+ sqe->msg_flags = (__u32)flags;
+}
+
+static inline void io_uring_prep_sendzc(struct io_uring_sqe *sqe, int sockfd,
+ const void *buf, size_t len, int flags,
+ unsigned int zc_flags)
+{
+ io_uring_prep_send(sqe, sockfd, buf, len, flags);
+ sqe->opcode = (__u8)IORING_OP_SEND_ZC;
+ sqe->ioprio = zc_flags;
+}
+
+static inline void io_uring_cqe_seen(struct io_uring *ring)
+{
+ *(&ring->cq)->khead += 1;
+ write_barrier();
+}
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 8b017070960d..f8d99837b9dc 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -98,6 +98,7 @@ $(OUTPUT)/reuseport_bpf_numa: LDLIBS += -lnuma
$(OUTPUT)/tcp_mmap: LDLIBS += -lpthread -lcrypto
$(OUTPUT)/tcp_inq: LDLIBS += -lpthread
$(OUTPUT)/bind_bhash: LDLIBS += -lpthread
+$(OUTPUT)/io_uring_zerocopy_tx: CFLAGS += -I../../../include/

# Rules to generate bpf obj nat6to4.o
CLANG ?= clang
diff --git a/tools/testing/selftests/net/io_uring_zerocopy_tx.c b/tools/testing/selftests/net/io_uring_zerocopy_tx.c
index 154287740172..76e604e4810e 100644
--- a/tools/testing/selftests/net/io_uring_zerocopy_tx.c
+++ b/tools/testing/selftests/net/io_uring_zerocopy_tx.c
@@ -36,6 +36,8 @@
#include <sys/un.h>
#include <sys/wait.h>

+#include <io_uring/mini_liburing.h>
+
#define NOTIF_TAG 0xfffffffULL
#define NONZC_TAG 0
#define ZC_TAG 1
@@ -60,272 +62,6 @@ static struct sockaddr_storage cfg_dst_addr;

static char payload[IP_MAXPACKET] __attribute__((aligned(4096)));

-struct io_sq_ring {
- unsigned *head;
- unsigned *tail;
- unsigned *ring_mask;
- unsigned *ring_entries;
- unsigned *flags;
- unsigned *array;
-};
-
-struct io_cq_ring {
- unsigned *head;
- unsigned *tail;
- unsigned *ring_mask;
- unsigned *ring_entries;
- struct io_uring_cqe *cqes;
-};
-
-struct io_uring_sq {
- unsigned *khead;
- unsigned *ktail;
- unsigned *kring_mask;
- unsigned *kring_entries;
- unsigned *kflags;
- unsigned *kdropped;
- unsigned *array;
- struct io_uring_sqe *sqes;
-
- unsigned sqe_head;
- unsigned sqe_tail;
-
- size_t ring_sz;
-};
-
-struct io_uring_cq {
- unsigned *khead;
- unsigned *ktail;
- unsigned *kring_mask;
- unsigned *kring_entries;
- unsigned *koverflow;
- struct io_uring_cqe *cqes;
-
- size_t ring_sz;
-};
-
-struct io_uring {
- struct io_uring_sq sq;
- struct io_uring_cq cq;
- int ring_fd;
-};
-
-#ifdef __alpha__
-# ifndef __NR_io_uring_setup
-# define __NR_io_uring_setup 535
-# endif
-# ifndef __NR_io_uring_enter
-# define __NR_io_uring_enter 536
-# endif
-# ifndef __NR_io_uring_register
-# define __NR_io_uring_register 537
-# endif
-#else /* !__alpha__ */
-# ifndef __NR_io_uring_setup
-# define __NR_io_uring_setup 425
-# endif
-# ifndef __NR_io_uring_enter
-# define __NR_io_uring_enter 426
-# endif
-# ifndef __NR_io_uring_register
-# define __NR_io_uring_register 427
-# endif
-#endif
-
-#if defined(__x86_64) || defined(__i386__)
-#define read_barrier() __asm__ __volatile__("":::"memory")
-#define write_barrier() __asm__ __volatile__("":::"memory")
-#else
-
-#define read_barrier() __sync_synchronize()
-#define write_barrier() __sync_synchronize()
-#endif
-
-static int io_uring_setup(unsigned int entries, struct io_uring_params *p)
-{
- return syscall(__NR_io_uring_setup, entries, p);
-}
-
-static int io_uring_enter(int fd, unsigned int to_submit,
- unsigned int min_complete,
- unsigned int flags, sigset_t *sig)
-{
- return syscall(__NR_io_uring_enter, fd, to_submit, min_complete,
- flags, sig, _NSIG / 8);
-}
-
-static int io_uring_register_buffers(struct io_uring *ring,
- const struct iovec *iovecs,
- unsigned nr_iovecs)
-{
- int ret;
-
- ret = syscall(__NR_io_uring_register, ring->ring_fd,
- IORING_REGISTER_BUFFERS, iovecs, nr_iovecs);
- return (ret < 0) ? -errno : ret;
-}
-
-static int io_uring_mmap(int fd, struct io_uring_params *p,
- struct io_uring_sq *sq, struct io_uring_cq *cq)
-{
- size_t size;
- void *ptr;
- int ret;
-
- sq->ring_sz = p->sq_off.array + p->sq_entries * sizeof(unsigned);
- ptr = mmap(0, sq->ring_sz, PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQ_RING);
- if (ptr == MAP_FAILED)
- return -errno;
- sq->khead = ptr + p->sq_off.head;
- sq->ktail = ptr + p->sq_off.tail;
- sq->kring_mask = ptr + p->sq_off.ring_mask;
- sq->kring_entries = ptr + p->sq_off.ring_entries;
- sq->kflags = ptr + p->sq_off.flags;
- sq->kdropped = ptr + p->sq_off.dropped;
- sq->array = ptr + p->sq_off.array;
-
- size = p->sq_entries * sizeof(struct io_uring_sqe);
- sq->sqes = mmap(0, size, PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQES);
- if (sq->sqes == MAP_FAILED) {
- ret = -errno;
-err:
- munmap(sq->khead, sq->ring_sz);
- return ret;
- }
-
- cq->ring_sz = p->cq_off.cqes + p->cq_entries * sizeof(struct io_uring_cqe);
- ptr = mmap(0, cq->ring_sz, PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_CQ_RING);
- if (ptr == MAP_FAILED) {
- ret = -errno;
- munmap(sq->sqes, p->sq_entries * sizeof(struct io_uring_sqe));
- goto err;
- }
- cq->khead = ptr + p->cq_off.head;
- cq->ktail = ptr + p->cq_off.tail;
- cq->kring_mask = ptr + p->cq_off.ring_mask;
- cq->kring_entries = ptr + p->cq_off.ring_entries;
- cq->koverflow = ptr + p->cq_off.overflow;
- cq->cqes = ptr + p->cq_off.cqes;
- return 0;
-}
-
-static int io_uring_queue_init(unsigned entries, struct io_uring *ring,
- unsigned flags)
-{
- struct io_uring_params p;
- int fd, ret;
-
- memset(ring, 0, sizeof(*ring));
- memset(&p, 0, sizeof(p));
- p.flags = flags;
-
- fd = io_uring_setup(entries, &p);
- if (fd < 0)
- return fd;
- ret = io_uring_mmap(fd, &p, &ring->sq, &ring->cq);
- if (!ret)
- ring->ring_fd = fd;
- else
- close(fd);
- return ret;
-}
-
-static int io_uring_submit(struct io_uring *ring)
-{
- struct io_uring_sq *sq = &ring->sq;
- const unsigned mask = *sq->kring_mask;
- unsigned ktail, submitted, to_submit;
- int ret;
-
- read_barrier();
- if (*sq->khead != *sq->ktail) {
- submitted = *sq->kring_entries;
- goto submit;
- }
- if (sq->sqe_head == sq->sqe_tail)
- return 0;
-
- ktail = *sq->ktail;
- to_submit = sq->sqe_tail - sq->sqe_head;
- for (submitted = 0; submitted < to_submit; submitted++) {
- read_barrier();
- sq->array[ktail++ & mask] = sq->sqe_head++ & mask;
- }
- if (!submitted)
- return 0;
-
- if (*sq->ktail != ktail) {
- write_barrier();
- *sq->ktail = ktail;
- write_barrier();
- }
-submit:
- ret = io_uring_enter(ring->ring_fd, submitted, 0,
- IORING_ENTER_GETEVENTS, NULL);
- return ret < 0 ? -errno : ret;
-}
-
-static inline void io_uring_prep_send(struct io_uring_sqe *sqe, int sockfd,
- const void *buf, size_t len, int flags)
-{
- memset(sqe, 0, sizeof(*sqe));
- sqe->opcode = (__u8) IORING_OP_SEND;
- sqe->fd = sockfd;
- sqe->addr = (unsigned long) buf;
- sqe->len = len;
- sqe->msg_flags = (__u32) flags;
-}
-
-static inline void io_uring_prep_sendzc(struct io_uring_sqe *sqe, int sockfd,
- const void *buf, size_t len, int flags,
- unsigned zc_flags)
-{
- io_uring_prep_send(sqe, sockfd, buf, len, flags);
- sqe->opcode = (__u8) IORING_OP_SEND_ZC;
- sqe->ioprio = zc_flags;
-}
-
-static struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring)
-{
- struct io_uring_sq *sq = &ring->sq;
-
- if (sq->sqe_tail + 1 - sq->sqe_head > *sq->kring_entries)
- return NULL;
- return &sq->sqes[sq->sqe_tail++ & *sq->kring_mask];
-}
-
-static int io_uring_wait_cqe(struct io_uring *ring, struct io_uring_cqe **cqe_ptr)
-{
- struct io_uring_cq *cq = &ring->cq;
- const unsigned mask = *cq->kring_mask;
- unsigned head = *cq->khead;
- int ret;
-
- *cqe_ptr = NULL;
- do {
- read_barrier();
- if (head != *cq->ktail) {
- *cqe_ptr = &cq->cqes[head & mask];
- break;
- }
- ret = io_uring_enter(ring->ring_fd, 0, 1,
- IORING_ENTER_GETEVENTS, NULL);
- if (ret < 0)
- return -errno;
- } while (1);
-
- return 0;
-}
-
-static inline void io_uring_cqe_seen(struct io_uring *ring)
-{
- *(&ring->cq)->khead += 1;
- write_barrier();
-}
-
static unsigned long gettimeofday_ms(void)
{
struct timeval tv;
--
2.34.1