[PATCH] syslet engine: use pread instead lseek+read

And similar for write. Saves executing an atom.

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

diff --git a/engines/syslet-rw.c b/engines/syslet-rw.c
index 380d19d44c4e3be8ba1af37853322d9c8b87a25a..32697a88c25b64a281a794b77b1674d54ac20410 100644 (file)
--- a/engines/syslet-rw.c
+++ b/engines/syslet-rw.c
@@ -91,17 +91,18 @@ static struct io_u *fio_syslet_event(struct thread_data *td, int event)
 }
 
 static void init_atom(struct syslet_uatom *atom, int nr, void *arg0,
-                     void *arg1, void *arg2, void *ret_ptr,
-                     unsigned long flags, void *priv,struct syslet_uatom *next)
+                     void *arg1, void *arg2, void *arg3, void *ret_ptr,
+                     unsigned long flags, void *priv)
 {
        atom->flags = flags;
        atom->nr = nr;
        atom->ret_ptr = ret_ptr;
-       atom->next = next;
+       atom->next = NULL;
        atom->arg_ptr[0] = arg0;
        atom->arg_ptr[1] = arg1;
        atom->arg_ptr[2] = arg2;
-       atom->arg_ptr[3] = atom->arg_ptr[4] = atom->arg_ptr[5] = NULL;
+       atom->arg_ptr[3] = arg3;
+       atom->arg_ptr[4] = atom->arg_ptr[5] = NULL;
        atom->private = priv;
 }
 
@@ -110,36 +111,25 @@ static void init_atom(struct syslet_uatom *atom, int nr, void *arg0,
  */
 static void fio_syslet_prep_sync(struct io_u *io_u, struct fio_file *f)
 {
-       init_atom(&io_u->seek_atom.atom, __NR_fsync, &f->fd, NULL, NULL,
-                 &io_u->seek_atom.ret, SYSLET_STOP_ON_NEGATIVE, io_u, NULL);
+       init_atom(&io_u->req.atom, __NR_fsync, &f->fd, NULL, NULL, NULL,
+                 &io_u->req.ret, SYSLET_STOP_ON_NEGATIVE, io_u);
 }
 
 static void fio_syslet_prep_rw(struct io_u *io_u, struct fio_file *f)
 {
        int nr;
 
-       /*
-        * prepare seek
-        */
-       io_u->seek_atom.cmd = SEEK_SET;
-       init_atom(&io_u->seek_atom.atom, __NR_lseek, &f->fd, &io_u->offset,
-                 &io_u->seek_atom.cmd, &io_u->seek_atom.ret,
-                 SYSLET_STOP_ON_NEGATIVE | SYSLET_NO_COMPLETE |
-                       SYSLET_SKIP_TO_NEXT_ON_STOP,
-                 NULL, &io_u->rw_atom.atom);
-
        /*
         * prepare rw
         */
        if (io_u->ddir == DDIR_READ)
-               nr = __NR_read;
+               nr = __NR_pread64;
        else
-               nr = __NR_write;
+               nr = __NR_pwrite64;
 
-       init_atom(&io_u->rw_atom.atom, nr, &f->fd, &io_u->xfer_buf,
-                 &io_u->xfer_buflen, &io_u->rw_atom.ret,
-                 SYSLET_STOP_ON_NEGATIVE | SYSLET_SKIP_TO_NEXT_ON_STOP,
-                 io_u, NULL);
+       init_atom(&io_u->req.atom, nr, &f->fd, &io_u->xfer_buf,
+                 &io_u->xfer_buflen, &io_u->offset, &io_u->req.ret,
+                 SYSLET_STOP_ON_NEGATIVE, io_u);
 }
 
 static int fio_syslet_prep(struct thread_data fio_unused *td, struct io_u *io_u)
@@ -160,14 +150,14 @@ static int fio_syslet_queue(struct thread_data *td, struct io_u *io_u)
        struct syslet_uatom *done;
        long ret;
 
-       done = async_exec(&io_u->seek_atom.atom);
+       done = async_exec(&io_u->req.atom);
        if (!done)
                return 0;
 
        /*
         * completed sync
         */
-       ret = io_u->rw_atom.ret;
+       ret = io_u->req.ret;
        if (ret != (long) io_u->xfer_buflen) {
                if (ret > 0) {
                        io_u->resid = io_u->xfer_buflen - ret;

diff --git a/fio.h b/fio.h
index ff59b467ba70dcf478959da266f681ec2495c9e7..2d30324cb973df5dc9c21f520f46e9ce5faee08c 100644 (file)
--- a/fio.h
+++ b/fio.h
@@ -70,7 +70,6 @@ struct io_piece {
 #ifdef FIO_HAVE_SYSLET
 struct syslet_req {
        struct syslet_uatom atom;
-       unsigned long cmd;
        long ret;
 };
 #endif
@@ -90,8 +89,7 @@ struct io_u {
                struct sg_io_hdr hdr;
 #endif
 #ifdef FIO_HAVE_SYSLET
-               struct syslet_req rw_atom;
-               struct syslet_req seek_atom;
+               struct syslet_req req;
 #endif
        };
        struct timeval start_time;