/*
- * read/write() engine that uses syslet to be async
+ * syslet engine
+ *
+ * IO engine that does regular pread(2)/pwrite(2) to transfer data, but
+ * with syslets to make the execution async.
*
*/
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <assert.h>
+#include <asm/unistd.h>
#include "../fio.h"
-#include "../os.h"
#ifdef FIO_HAVE_SYSLET
+#ifdef __NR_pread64
+#define __NR_fio_pread __NR_pread64
+#define __NR_fio_pwrite __NR_pwrite64
+#else
+#define __NR_fio_pread __NR_pread
+#define __NR_fio_pwrite __NR_pwrite
+#endif
+
struct syslet_data {
struct io_u **events;
unsigned int nr_events;
+ struct async_head_user ahu;
struct syslet_uatom **ring;
- unsigned int ring_index;
+
+ struct syslet_uatom *head, *tail;
};
+static void fio_syslet_complete_atom(struct thread_data *td,
+ struct syslet_uatom *atom)
+{
+ struct syslet_data *sd = td->io_ops->data;
+ struct syslet_uatom *last;
+ struct io_u *io_u;
+
+ /*
+ * complete from the beginning of the sequence up to (and
+ * including) this atom
+ */
+ last = atom;
+ io_u = atom->private;
+ atom = io_u->req.head;
+
+ /*
+ * now complete in right order
+ */
+ do {
+ long ret;
+
+ io_u = atom->private;
+ ret = *atom->ret_ptr;
+ if (ret >= 0)
+ io_u->resid = io_u->xfer_buflen - ret;
+ else if (ret < 0)
+ io_u->error = ret;
+
+ assert(sd->nr_events < td->o.iodepth);
+ sd->events[sd->nr_events++] = io_u;
+
+ if (atom == last)
+ break;
+
+ atom = atom->next;
+ } while (1);
+
+ assert(!last->next);
+}
+
/*
* Inspect the ring to see if we have completed events
*/
do {
struct syslet_uatom *atom;
- struct io_u *io_u;
- long ret;
- atom = sd->ring[sd->ring_index];
+ atom = sd->ring[sd->ahu.user_ring_idx];
if (!atom)
break;
- sd->ring[sd->ring_index] = NULL;
- if (++sd->ring_index == td->iodepth)
- sd->ring_index = 0;
+ sd->ring[sd->ahu.user_ring_idx] = NULL;
+ if (++sd->ahu.user_ring_idx == td->o.iodepth)
+ sd->ahu.user_ring_idx = 0;
- io_u = atom->private;
- ret = *atom->ret_ptr;
- if (ret > 0)
- io_u->resid = io_u->xfer_buflen - ret;
- else if (ret < 0)
- io_u->error = ret;
-
- sd->events[sd->nr_events++] = io_u;
+ fio_syslet_complete_atom(td, atom);
} while (1);
}
struct timespec fio_unused *t)
{
struct syslet_data *sd = td->io_ops->data;
- int get_events;
long ret;
do {
/*
* OK, we need to wait for some events...
*/
- get_events = min - sd->nr_events;
- ret = async_wait(get_events);
+ ret = async_wait(1, sd->ahu.user_ring_idx, &sd->ahu);
if (ret < 0)
- return errno;
+ return -errno;
} while (1);
ret = sd->nr_events;
}
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;
}
*/
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, 0, 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_fio_pread;
else
- nr = __NR_write;
+ nr = __NR_fio_pwrite;
- 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, 0, io_u);
}
static int fio_syslet_prep(struct thread_data fio_unused *td, struct io_u *io_u)
return 0;
}
-static int fio_syslet_queue(struct thread_data *td, struct io_u *io_u)
+static void cachemiss_thread_start(void)
+{
+ while (1)
+ async_thread(NULL, NULL);
+}
+
+#define THREAD_STACK_SIZE (16384)
+
+static unsigned long thread_stack_alloc()
+{
+ return (unsigned long) malloc(THREAD_STACK_SIZE) + THREAD_STACK_SIZE;
+}
+
+static void fio_syslet_queued(struct thread_data *td, struct syslet_data *sd)
+{
+ struct syslet_uatom *atom;
+ struct timeval now;
+
+ fio_gettime(&now, NULL);
+
+ atom = sd->head;
+ while (atom) {
+ struct io_u *io_u = atom->private;
+
+ memcpy(&io_u->issue_time, &now, sizeof(now));
+ io_u_queued(td, io_u);
+ atom = atom->next;
+ }
+}
+
+static int fio_syslet_commit(struct thread_data *td)
{
struct syslet_data *sd = td->io_ops->data;
struct syslet_uatom *done;
- long ret;
- done = async_exec(&io_u->seek_atom.atom);
- if (!done)
+ if (!sd->head)
return 0;
+ assert(!sd->tail->next);
+
+ if (!sd->ahu.new_thread_stack)
+ sd->ahu.new_thread_stack = thread_stack_alloc();
+
+ fio_syslet_queued(td, sd);
+
/*
- * completed sync
+ * On sync completion, the atom is returned. So on NULL return
+ * it's queued asynchronously.
*/
- ret = io_u->rw_atom.ret;
- if (ret != (long) io_u->xfer_buflen) {
- if (ret > 0) {
- io_u->resid = io_u->xfer_buflen - ret;
- io_u->error = 0;
- return ret;
- } else
- io_u->error = errno;
+ done = async_exec(sd->head, &sd->ahu);
+
+ if (done == (void *) -1) {
+ log_err("fio: syslets don't appear to work\n");
+ return -1;
}
- if (!io_u->error)
- sd->events[sd->nr_events++] = io_u;
- else
- td_verror(td, io_u->error);
+ sd->head = sd->tail = NULL;
+
+ if (done)
+ fio_syslet_complete_atom(td, done);
- return io_u->error;
+ return 0;
}
-static void async_head_init(struct syslet_data *sd, unsigned int depth)
+static int fio_syslet_queue(struct thread_data *td, struct io_u *io_u)
+{
+ struct syslet_data *sd = td->io_ops->data;
+
+ if (sd->tail) {
+ sd->tail->next = &io_u->req.atom;
+ sd->tail = &io_u->req.atom;
+ } else
+ sd->head = sd->tail = &io_u->req.atom;
+
+ io_u->req.head = sd->head;
+ return FIO_Q_QUEUED;
+}
+
+static int async_head_init(struct syslet_data *sd, unsigned int depth)
{
- struct async_head_user ahu;
unsigned long ring_size;
+ memset(&sd->ahu, 0, sizeof(struct async_head_user));
+
ring_size = sizeof(struct syslet_uatom *) * depth;
sd->ring = malloc(ring_size);
memset(sd->ring, 0, ring_size);
- memset(&ahu, 0, sizeof(ahu));
- ahu.completion_ring = sd->ring;
- ahu.ring_size_bytes = ring_size;
- ahu.max_nr_threads = -1;
+ sd->ahu.user_ring_idx = 0;
+ sd->ahu.completion_ring = sd->ring;
+ sd->ahu.ring_size_bytes = ring_size;
+ sd->ahu.head_stack = thread_stack_alloc();
+ sd->ahu.head_eip = (unsigned long) cachemiss_thread_start;
+ sd->ahu.new_thread_eip = (unsigned long) cachemiss_thread_start;
- if (async_register(&ahu, sizeof(ahu)) < 0)
- perror("async_register");
+ return 0;
}
-static void async_head_exit(struct syslet_data *sd, unsigned int depth)
+static void async_head_exit(struct syslet_data *sd)
{
- struct async_head_user ahu;
+ free(sd->ring);
+}
- memset(&ahu, 0, sizeof(ahu));
- ahu.completion_ring = sd->ring;
- ahu.ring_size_bytes = sizeof(struct syslet_uatom *) * depth;
+static int check_syslet_support(struct syslet_data *sd)
+{
+ struct syslet_uatom atom;
+ void *ret;
- if (async_unregister(&ahu, sizeof(ahu)) < 0)
- perror("async_register");
+ init_atom(&atom, __NR_getpid, NULL, NULL, NULL, NULL, NULL, 0, NULL);
+ ret = async_exec(sd->head, &sd->ahu);
+ if (ret == (void *) -1)
+ return 1;
+
+ return 0;
}
static void fio_syslet_cleanup(struct thread_data *td)
struct syslet_data *sd = td->io_ops->data;
if (sd) {
- async_head_exit(sd, td->iodepth);
+ async_head_exit(sd);
free(sd->events);
free(sd);
td->io_ops->data = NULL;
sd = malloc(sizeof(*sd));
memset(sd, 0, sizeof(*sd));
- sd->events = malloc(sizeof(struct io_u *) * td->iodepth);
- memset(sd->events, 0, sizeof(struct io_u *) * td->iodepth);
+ sd->events = malloc(sizeof(struct io_u *) * td->o.iodepth);
+ memset(sd->events, 0, sizeof(struct io_u *) * td->o.iodepth);
+
+ /*
+ * This will handily fail for kernels where syslet isn't available
+ */
+ if (async_head_init(sd, td->o.iodepth)) {
+ free(sd->events);
+ free(sd);
+ return 1;
+ }
+
+ if (check_syslet_support(sd)) {
+ log_err("fio: syslets do not appear to work\n");
+ free(sd->events);
+ free(sd);
+ return 1;
+ }
+
td->io_ops->data = sd;
- async_head_init(sd, td->iodepth);
return 0;
}
.init = fio_syslet_init,
.prep = fio_syslet_prep,
.queue = fio_syslet_queue,
+ .commit = fio_syslet_commit,
.getevents = fio_syslet_getevents,
.event = fio_syslet_event,
.cleanup = fio_syslet_cleanup,
+ .open_file = generic_open_file,
+ .close_file = generic_close_file,
};
#else /* FIO_HAVE_SYSLET */
projects / fio.git / blobdiff