net engine: cleanup the splice handling

The splice and vmsplice bits were largely duplicated, so abstract
the stuff out so it's clearer to see what is going on.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/engines/net.c b/engines/net.c
index 4538a04d3d829dcf22dfa5f5ba6b5ed429dc96f0..52e3b049690dac057147122de59358de81b0fb0b 100644 (file)
--- a/engines/net.c
+++ b/engines/net.c
@@ -52,18 +52,12 @@ static int fio_netio_prep(struct thread_data *td, struct io_u *io_u)
        return 1;
 }
 
-/*
- * Receive bytes from a socket and fill them into the internal pipe
- */
-static int splice_in(struct thread_data *td, struct io_u *io_u)
+static int splice_io_u(int fdin, int fdout, unsigned int len)
 {
-       struct netio_data *nd = td->io_ops->data;
-       unsigned int len = io_u->xfer_buflen;
-       struct fio_file *f = io_u->file;
        int bytes = 0;
 
        while (len) {
-               int ret = splice(f->fd, NULL, nd->pipes[1], NULL, len, 0);
+               int ret = splice(fdin, NULL, fdout, NULL, len, 0);
 
                if (ret < 0) {
                        if (!bytes)
@@ -81,40 +75,28 @@ static int splice_in(struct thread_data *td, struct io_u *io_u)
 }
 
 /*
- * Transmit 'len' bytes from the internal pipe
+ * Receive bytes from a socket and fill them into the internal pipe
  */
-static int splice_out(struct thread_data *td, struct io_u *io_u,
-                     unsigned int len)
+static int splice_in(struct thread_data *td, struct io_u *io_u)
 {
        struct netio_data *nd = td->io_ops->data;
-       struct fio_file *f = io_u->file;
-       int bytes = 0;
 
-       while (len) {
-               int ret = splice(nd->pipes[0], NULL, f->fd, NULL, len, 0);
-
-               if (ret < 0) {
-                       if (!bytes)
-                               bytes = ret;
-                       
-                       break;
-               } else if (!ret)
-                       break;
-
-               bytes += ret;
-               len -= ret;
-       }
-
-       return bytes;
+       return splice_io_u(io_u->file->fd, nd->pipes[1], io_u->xfer_buflen);
 }
 
 /*
- * vmsplice() pipe to io_u buffer
+ * Transmit 'len' bytes from the internal pipe
  */
-static int vmsplice_io_u_out(struct thread_data *td, struct io_u *io_u,
-                            unsigned int len)
+static int splice_out(struct thread_data *td, struct io_u *io_u,
+                     unsigned int len)
 {
        struct netio_data *nd = td->io_ops->data;
+
+       return splice_io_u(nd->pipes[0], io_u->file->fd, len);
+}
+
+static int vmsplice_io_u(struct io_u *io_u, int fd, unsigned int len)
+{
        struct iovec iov = {
                .iov_base = io_u->xfer_buf,
                .iov_len = len,
@@ -122,7 +104,7 @@ static int vmsplice_io_u_out(struct thread_data *td, struct io_u *io_u,
        int bytes = 0;
 
        while (iov.iov_len) {
-               int ret = vmsplice(nd->pipes[0], &iov, 1, SPLICE_F_MOVE);
+               int ret = vmsplice(fd, &iov, 1, SPLICE_F_MOVE);
 
                if (ret < 0) {
                        if (!bytes)
@@ -132,63 +114,63 @@ static int vmsplice_io_u_out(struct thread_data *td, struct io_u *io_u,
                        break;
 
                iov.iov_len -= ret;
+               iov.iov_base += ret;
                bytes += ret;
-               if (iov.iov_len)
-                       iov.iov_base += ret;
        }
 
        return bytes;
+
 }
 
 /*
- * vmsplice() io_u to pipe
+ * vmsplice() pipe to io_u buffer
  */
-static int vmsplice_io_u_in(struct thread_data *td, struct io_u *io_u)
+static int vmsplice_io_u_out(struct thread_data *td, struct io_u *io_u,
+                            unsigned int len)
 {
        struct netio_data *nd = td->io_ops->data;
-       struct iovec iov = {
-               .iov_base = io_u->xfer_buf,
-               .iov_len = io_u->xfer_buflen,
-       };
-       unsigned int bytes = 0;
 
-       while (iov.iov_len) {
-               int ret = vmsplice(nd->pipes[1], &iov, 1, SPLICE_F_MOVE);
-
-               if (ret < 0)
-                       return -1;
-               else if (!ret)
-                       return bytes;
+       return vmsplice_io_u(io_u, nd->pipes[0], len);
+}
 
-               iov.iov_len -= ret;
-               bytes += ret;
-               if (iov.iov_len)
-                       iov.iov_base += ret;
-       }
+/*
+ * vmsplice() io_u to pipe
+ */
+static int vmsplice_io_u_in(struct thread_data *td, struct io_u *io_u)
+{
+       struct netio_data *nd = td->io_ops->data;
 
-       return bytes;
+       return vmsplice_io_u(io_u, nd->pipes[1], io_u->xfer_buflen);
 }
 
+/*
+ * splice receive - transfer socket data into a pipe using splice, then map
+ * that pipe data into the io_u using vmsplice.
+ */
 static int fio_netio_splice_in(struct thread_data *td, struct io_u *io_u)
 {
        int ret;
 
        ret = splice_in(td, io_u);
-       if (ret <= 0)
-               return ret;
+       if (ret > 0)
+               return vmsplice_io_u_out(td, io_u, ret);
 
-       return vmsplice_io_u_out(td, io_u, ret);
+       return ret;
 }
 
+/*
+ * splice transmit - map data from the io_u into a pipe by using vmsplice,
+ * then transfer that pipe to a socket using splice.
+ */
 static int fio_netio_splice_out(struct thread_data *td, struct io_u *io_u)
 {
        int ret;
 
        ret = vmsplice_io_u_in(td, io_u);
-       if (ret <= 0)
-               return ret;
+       if (ret > 0)
+               return splice_out(td, io_u, ret);
 
-       return splice_out(td, io_u, ret);
+       return ret;
 }
 
 static int fio_netio_send(struct thread_data *td, struct io_u *io_u)
@@ -306,7 +288,6 @@ static int fio_netio_accept(struct thread_data *td, struct fio_file *f)
        return 0;
 }
 
-
 static int fio_netio_open_file(struct thread_data *td, struct fio_file *f)
 {
        if (td_read(td))