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Update to newer API

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Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe
2019-01-09 15:26:20 -07:00
parent 66a7d05bd8
commit 7bf7e8e8e5
5 changed files with 129 additions and 115 deletions
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66
src/io_uring.c
View File

@@ -10,18 +10,18 @@
#include "barrier.h"
static int __io_uring_get_completion(int fd, struct io_uring_cq *cq,
struct io_uring_event **ev_ptr, int wait)
struct io_uring_cqe **cqe_ptr, int wait)
{
const unsigned mask = *cq->kring_mask;
unsigned head;
int ret;
*ev_ptr = NULL;
*cqe_ptr = NULL;
head = *cq->khead;
do {
read_barrier();
if (head != *cq->ktail) {
*ev_ptr = &cq->events[head & mask];
*cqe_ptr = &cq->cqes[head & mask];
break;
}
if (!wait)
@@ -31,7 +31,7 @@ static int __io_uring_get_completion(int fd, struct io_uring_cq *cq,
return -errno;
} while (1);
if (*ev_ptr) {
if (*cqe_ptr) {
*cq->khead = head + 1;
write_barrier();
}
@@ -43,24 +43,24 @@ static int __io_uring_get_completion(int fd, struct io_uring_cq *cq,
* Return an IO completion, if one is readily available
*/
int io_uring_get_completion(struct io_uring *ring,
struct io_uring_event **ev_ptr)
struct io_uring_cqe **cqe_ptr)
{
return __io_uring_get_completion(ring->ring_fd, &ring->cq, ev_ptr, 0);
return __io_uring_get_completion(ring->ring_fd, &ring->cq, cqe_ptr, 0);
}
/*
* Return an IO completion, waiting for it if necessary
*/
int io_uring_wait_completion(struct io_uring *ring,
struct io_uring_event **ev_ptr)
struct io_uring_cqe **cqe_ptr)
{
return __io_uring_get_completion(ring->ring_fd, &ring->cq, ev_ptr, 1);
return __io_uring_get_completion(ring->ring_fd, &ring->cq, cqe_ptr, 1);
}
/*
* Submit iocbs acquired from io_uring_get_iocb() to the kernel.
* Submit sqes acquired from io_uring_get_sqe() to the kernel.
*
* Returns number of iocbs submitted
* Returns number of sqes submitted
*/
int io_uring_submit(struct io_uring *ring)
{
@@ -77,24 +77,24 @@ int io_uring_submit(struct io_uring *ring)
goto submit;
}
if (sq->iocb_head == sq->iocb_tail)
if (sq->sqe_head == sq->sqe_tail)
return 0;
/*
* Fill in iocbs that we have queued up, adding them to the kernel ring
* Fill in sqes that we have queued up, adding them to the kernel ring
*/
submitted = 0;
ktail = ktail_next = *sq->ktail;
while (sq->iocb_head < sq->iocb_tail) {
while (sq->sqe_head < sq->sqe_tail) {
ktail_next++;
read_barrier();
if (ktail_next == *sq->khead)
break;
sq->array[ktail & mask] = sq->iocb_head & mask;
sq->array[ktail & mask] = sq->sqe_head & mask;
ktail = ktail_next;
sq->iocb_head++;
sq->sqe_head++;
submitted++;
}
@@ -113,27 +113,27 @@ submit:
}
/*
* Return an iocb to fill. Application must later call io_uring_submit()
* Return an sqe to fill. Application must later call io_uring_submit()
* when it's ready to tell the kernel about it. The caller may call this
* function multiple times before calling io_uring_submit().
*
* Returns a vacant iocb, or NULL if we're full.
* Returns a vacant sqe, or NULL if we're full.
*/
struct io_uring_iocb *io_uring_get_iocb(struct io_uring *ring)
struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring)
{
struct io_uring_sq *sq = &ring->sq;
unsigned next = sq->iocb_tail + 1;
struct io_uring_iocb *iocb;
unsigned next = sq->sqe_tail + 1;
struct io_uring_sqe *sqe;
/*
* All iocbs are used
* All sqes are used
*/
if (next - sq->iocb_head > *sq->kring_entries)
if (next - sq->sqe_head > *sq->kring_entries)
return NULL;
iocb = &sq->iocbs[sq->iocb_tail & *sq->kring_mask];
sq->iocb_tail = next;
return iocb;
sqe = &sq->sqes[sq->sqe_tail & *sq->kring_mask];
sq->sqe_tail = next;
return sqe;
}
static int io_uring_mmap(int fd, struct io_uring_params *p,
@@ -156,23 +156,23 @@ static int io_uring_mmap(int fd, struct io_uring_params *p,
sq->kdropped = ptr + p->sq_off.dropped;
sq->array = ptr + p->sq_off.array;
size = p->sq_entries * sizeof(struct io_uring_iocb);
sq->iocbs = mmap(0, size, PROT_READ | PROT_WRITE,
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_IOCB);
if (sq->iocbs == MAP_FAILED) {
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.events + p->cq_entries * sizeof(struct io_uring_event);
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->iocbs, p->sq_entries * sizeof(struct io_uring_iocb));
munmap(sq->sqes, p->sq_entries * sizeof(struct io_uring_sqe));
goto err;
}
cq->khead = ptr + p->cq_off.head;
@@ -180,7 +180,7 @@ err:
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->events = ptr + p->cq_off.events;
cq->cqes = ptr + p->cq_off.cqes;
return 0;
}
@@ -209,7 +209,7 @@ void io_uring_queue_exit(struct io_uring *ring)
struct io_uring_sq *sq = &ring->sq;
struct io_uring_cq *cq = &ring->cq;
munmap(sq->iocbs, *sq->kring_entries * sizeof(struct io_uring_iocb));
munmap(sq->sqes, *sq->kring_entries * sizeof(struct io_uring_sqe));
munmap(sq->khead, sq->ring_sz);
munmap(cq->khead, cq->ring_sz);
close(ring->ring_fd);

27
src/io_uring.h
View File

@@ -12,9 +12,9 @@
#include <linux/types.h>
/*
* IO submission data structure
* IO submission data structure (Submission Queue Entry)
*/
struct io_uring_iocb {
struct io_uring_sqe {
__u8 opcode;
__u8 flags;
__u16 ioprio;
@@ -35,23 +35,22 @@ struct io_uring_iocb {
* io_uring_setup() flags
*/
#define IORING_SETUP_IOPOLL (1 << 0) /* io_context is polled */
#define IORING_SETUP_FIXEDBUFS (1 << 1) /* IO buffers are fixed */
#define IORING_SETUP_SQTHREAD (1 << 2) /* Use SQ thread */
#define IORING_SETUP_SQWQ (1 << 3) /* Use SQ workqueue */
#define IORING_SETUP_SQPOLL (1 << 4) /* SQ thread polls */
#define IORING_SETUP_SQTHREAD (1 << 1) /* Use SQ thread */
#define IORING_SETUP_SQWQ (1 << 2) /* Use SQ workqueue */
#define IORING_SETUP_SQPOLL (1 << 3) /* SQ thread polls */
#define IORING_OP_READ 1
#define IORING_OP_WRITE 2
#define IORING_OP_READV 1
#define IORING_OP_WRITEV 2
#define IORING_OP_FSYNC 3
#define IORING_OP_FDSYNC 4
#define IORING_OP_READ_FIXED 5
#define IORING_OP_WRITE_FIXED 6
/*
* IO completion data structure
* IO completion data structure (Completion Queue Entry)
*/
struct io_uring_event {
__u64 index; /* what iocb this event came from */
struct io_uring_cqe {
__u64 index; /* what sqe this event came from */
__s32 res; /* result code for this event */
__u32 flags;
};
@@ -59,14 +58,14 @@ struct io_uring_event {
/*
* io_uring_event->flags
*/
#define IOEV_FLAG_CACHEHIT (1 << 0) /* IO did not hit media */
#define IOCQE_FLAG_CACHEHIT (1 << 0) /* IO did not hit media */
/*
* Magic offsets for the application to mmap the data it needs
*/
#define IORING_OFF_SQ_RING 0ULL
#define IORING_OFF_CQ_RING 0x8000000ULL
#define IORING_OFF_IOCB 0x10000000ULL
#define IORING_OFF_SQES 0x10000000ULL
/*
* Filled with the offset for mmap(2)
@@ -90,7 +89,7 @@ struct io_cqring_offsets {
__u32 ring_mask;
__u32 ring_entries;
__u32 overflow;
__u32 events;
__u32 cqes;
__u32 resv[4];
};

20
src/liburing.h
View File

@@ -15,10 +15,10 @@ struct io_uring_sq {
unsigned *kflags;
unsigned *kdropped;
unsigned *array;
struct io_uring_iocb *iocbs;
struct io_uring_sqe *sqes;
unsigned iocb_head;
unsigned iocb_tail;
unsigned sqe_head;
unsigned sqe_tail;
size_t ring_sz;
};
@@ -29,7 +29,7 @@ struct io_uring_cq {
unsigned *kring_mask;
unsigned *kring_entries;
unsigned *koverflow;
struct io_uring_event *events;
struct io_uring_cqe *cqes;
size_t ring_sz;
};
@@ -55,16 +55,16 @@ extern int io_uring_queue_init(unsigned entries, struct io_uring_params *p,
struct iovec *iovecs, struct io_uring *ring);
extern void io_uring_queue_exit(struct io_uring *ring);
extern int io_uring_get_completion(struct io_uring *ring,
struct io_uring_event **ev_ptr);
struct io_uring_cqe **cqe_ptr);
extern int io_uring_wait_completion(struct io_uring *ring,
struct io_uring_event **ev_ptr);
struct io_uring_cqe **cqe_ptr);
extern int io_uring_submit(struct io_uring *ring);
extern struct io_uring_iocb *io_uring_get_iocb(struct io_uring *ring);
extern struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring);
static inline struct io_uring_iocb *
io_uring_iocb_from_ev(struct io_uring *ring, struct io_uring_event *ev)
static inline struct io_uring_sqe *
io_uring_sqe_from_cqe(struct io_uring *ring, struct io_uring_cqe *cqe)
{
return &ring->sq.iocbs[ev->index];
return &ring->sq.sqes[cqe->index];
}
#endif

85
test/io_uring-cp.c
View File

@@ -16,7 +16,7 @@
static struct io_uring in_ring;
static struct io_uring out_ring;
static void *bufs[QD];
static struct iovec iovecs[QD];
static int setup_context(unsigned entries, struct io_uring *ring, int offload)
{
@@ -50,26 +50,27 @@ static int get_file_size(int fd, off_t *size)
return -1;
}
static unsigned iocb_index(struct io_uring_iocb *iocb)
static unsigned sqe_index(struct io_uring_sqe *sqe)
{
return iocb - in_ring.sq.iocbs;
return sqe - in_ring.sq.sqes;
}
static int queue_read(int fd, off_t size, off_t offset)
{
struct io_uring_iocb *iocb;
struct io_uring_sqe *sqe;
iocb = io_uring_get_iocb(&in_ring);
if (!iocb)
sqe = io_uring_get_sqe(&in_ring);
if (!sqe)
return 1;
iocb->opcode = IORING_OP_READ;
iocb->flags = 0;
iocb->ioprio = 0;
iocb->fd = fd;
iocb->off = offset;
iocb->addr = bufs[iocb_index(iocb)];
iocb->len = size;
sqe->opcode = IORING_OP_READV;
sqe->flags = 0;
sqe->ioprio = 0;
sqe->fd = fd;
sqe->off = offset;
sqe->addr = &iovecs[sqe_index(sqe)];
iovecs[sqe_index(sqe)].iov_len = size;
sqe->len = 1;
return 0;
}
@@ -85,16 +86,16 @@ static int complete_writes(unsigned *writes)
nr = ret;
while (nr) {
struct io_uring_event *ev = NULL;
struct io_uring_cqe *cqe;
ret = io_uring_wait_completion(&out_ring, &ev);
ret = io_uring_wait_completion(&out_ring, &cqe);
if (ret < 0) {
fprintf(stderr, "io_uring_wait_completion: %s\n",
strerror(-ret));
return 1;
}
if (ev->res < 0) {
fprintf(stderr, "ev failed: %s\n", strerror(-ev->res));
if (cqe->res < 0) {
fprintf(stderr, "cqe failed: %s\n", strerror(-cqe->res));
return 1;
}
(*writes)--;
@@ -106,22 +107,23 @@ static int complete_writes(unsigned *writes)
static void queue_write(int fd, off_t size, off_t offset, unsigned index)
{
struct io_uring_iocb *iocb;
struct io_uring_sqe *sqe;
iocb = io_uring_get_iocb(&out_ring);
iocb->opcode = IORING_OP_WRITE;
iocb->flags = 0;
iocb->ioprio = 0;
iocb->fd = fd;
iocb->off = offset;
iocb->addr = bufs[index];
iocb->len = size;
sqe = io_uring_get_sqe(&out_ring);
sqe->opcode = IORING_OP_WRITEV;
sqe->flags = 0;
sqe->ioprio = 0;
sqe->fd = fd;
sqe->off = offset;
sqe->addr = &iovecs[index];
iovecs[index].iov_len = size;
sqe->len = 1;
}
int main(int argc, char *argv[])
{
struct io_uring_event *ev;
off_t read_left, write_left, offset;
struct io_uring_cqe *cqe;
int i, infd, outfd, ret;
unsigned reads, writes;
@@ -141,9 +143,14 @@ int main(int argc, char *argv[])
return 1;
}
for (i = 0; i < QD; i++)
if (posix_memalign(&bufs[i], BS, BS))
for (i = 0; i < QD; i++) {
void *buf;
if (posix_memalign(&buf, BS, BS))
return 1;
iovecs[i].iov_base = buf;
iovecs[i].iov_len = BS;
}
if (setup_context(QD, &in_ring, 1))
return 1;
@@ -157,7 +164,7 @@ int main(int argc, char *argv[])
write_left = read_left;
while (read_left || write_left) {
off_t this_size = read_left;
struct io_uring_iocb *iocb;
struct io_uring_sqe *sqe;
if (this_size > BS)
this_size = BS;
@@ -186,25 +193,25 @@ skip_read:
*/
while (reads || write_left) {
if (reads)
ret = io_uring_wait_completion(&in_ring, &ev);
ret = io_uring_wait_completion(&in_ring, &cqe);
else
ret = io_uring_get_completion(&in_ring, &ev);
ret = io_uring_get_completion(&in_ring, &cqe);
if (ret < 0) {
fprintf(stderr, "io_uring_get_completion: %s\n",
strerror(-ret));
return 1;
}
if (!ev)
if (!cqe)
break;
reads--;
if (ev->res < 0) {
fprintf(stderr, "ev failed: %s\n",
strerror(-ev->res));
if (cqe->res < 0) {
fprintf(stderr, "cqe failed: %s\n",
strerror(-cqe->res));
return 1;
}
iocb = io_uring_iocb_from_ev(&in_ring, ev);
queue_write(outfd, ev->res, iocb->off, ev->index);
write_left -= ev->res;
sqe = io_uring_sqe_from_cqe(&in_ring, cqe);
queue_write(outfd, cqe->res, sqe->off, cqe->index);
write_left -= cqe->res;
writes++;
};
if (complete_writes(&writes))

46
test/io_uring-test.c
View File

@@ -11,13 +11,16 @@
#include <unistd.h>
#include "../src/liburing.h"
#define QD 4
int main(int argc, char *argv[])
{
struct io_uring_params p;
struct io_uring ring;
int i, fd, ret, pending, done;
struct io_uring_iocb *iocb;
struct io_uring_event *ev;
struct io_uring_sqe *sqe;
struct io_uring_cqe *cqe;
struct iovec *iovecs;
off_t offset;
void *buf;
@@ -29,7 +32,7 @@ int main(int argc, char *argv[])
memset(&p, 0, sizeof(p));
p.flags = IORING_SETUP_IOPOLL;
ret = io_uring_queue_init(4, &p, NULL, &ring);
ret = io_uring_queue_init(QD, &p, NULL, &ring);
if (ret < 0) {
fprintf(stderr, "queue_init: %s\n", strerror(-ret));
return 1;
@@ -41,22 +44,28 @@ int main(int argc, char *argv[])
return 1;
}
if (posix_memalign(&buf, 4096, 4096))
return 1;
iovecs = calloc(QD, sizeof(struct iovec));
for (i = 0; i < QD; i++) {
if (posix_memalign(&buf, 4096, 4096))
return 1;
iovecs[i].iov_base = buf;
iovecs[i].iov_len = 4096;
}
offset = 0;
i = 0;
do {
iocb = io_uring_get_iocb(&ring);
if (!iocb)
sqe = io_uring_get_sqe(&ring);
if (!sqe)
break;
iocb->opcode = IORING_OP_READ;
iocb->flags = 0;
iocb->ioprio = 0;
iocb->fd = fd;
iocb->off = offset;
iocb->addr = buf;
iocb->len = 4096;
offset += 4096;
sqe->opcode = IORING_OP_READV;
sqe->flags = 0;
sqe->ioprio = 0;
sqe->fd = fd;
sqe->off = offset;
sqe->addr = &iovecs[i];
sqe->len = 1;
offset += iovecs[i].iov_len;
} while (1);
ret = io_uring_submit(&ring);
@@ -68,16 +77,15 @@ int main(int argc, char *argv[])
done = 0;
pending = ret;
for (i = 0; i < pending; i++) {
ev = NULL;
ret = io_uring_get_completion(&ring, &ev);
ret = io_uring_get_completion(&ring, &cqe);
if (ret < 0) {
fprintf(stderr, "io_uring_get_completion: %s\n", strerror(-ret));
return 1;
}
done++;
if (ev->res != 4096) {
fprintf(stderr, "ret=%d, wanted 4096\n", ev->res);
if (cqe->res != 4096) {
fprintf(stderr, "ret=%d, wanted 4096\n", cqe->res);
return 1;
}
}