solarisaio: support signal driven async IO

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

diff --git a/engines/solarisaio.c b/engines/solarisaio.c
index f7f832b8b9ae66842011274f6053ac82ab0f9dde..b519fc54339b0ddde7fb3192db3b6afda9d9d64c 100644 (file)
--- a/engines/solarisaio.c
+++ b/engines/solarisaio.c
@@ -5,6 +5,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <signal.h>
 #include <errno.h>
 
 #include "../fio.h"
@@ -15,6 +16,7 @@
 
 struct solarisaio_data {
        struct io_u **aio_events;
+       unsigned int aio_pending;
        unsigned int nr;
        unsigned int max_depth;
 };
@@ -28,54 +30,78 @@ static int fio_solarisaio_cancel(struct thread_data fio_unused *td,
 static int fio_solarisaio_prep(struct thread_data fio_unused *td,
                            struct io_u *io_u)
 {
+       struct solarisaio_data *sd = td->io_ops->data;
+
        io_u->resultp.aio_return = AIO_INPROGRESS;
+       io_u->engine_data = sd;
        return 0;
 }
 
+static void wait_for_event(struct timeval *tv)
+{
+       struct solarisaio_data *sd;
+       struct io_u *io_u;
+       aio_result_t *res;
+
+       res = aiowait(tv);
+       if (res == (aio_result_t *) -1) {
+               int err = errno;
+
+               if (err != EINVAL) {
+                       log_err("fio: solarisaio got %d in aiowait\n", err);
+                       exit(err);
+               }
+               return;
+       } else if (!res)
+               return;
+
+       io_u = container_of(res, struct io_u, resultp);
+       sd = io_u->engine_data;
+
+       if (io_u->resultp.aio_return >= 0) {
+               io_u->resid = io_u->xfer_buflen - io_u->resultp.aio_return;
+               io_u->error = 0;
+       } else
+               io_u->error = io_u->resultp.aio_return;
+
+       /*
+        * For SIGIO, we need a write barrier between the two, so that
+        * the ->aio_pending store is seen after the ->aio_events store
+        */
+       sd->aio_events[sd->aio_pending] = io_u;
+       sd->aio_pending++;
+       sd->nr--;
+}
+
+static void fio_solarisaio_sigio(int sig)
+{
+       wait_for_event(NULL);
+}
+
 static int fio_solarisaio_getevents(struct thread_data *td, unsigned int min,
                                    unsigned int max, struct timespec *t)
 {
        struct solarisaio_data *sd = td->io_ops->data;
        struct timeval tv;
-       unsigned int r;
-
-       r = 0;
-       do {
-               struct io_u *io_u;
-               aio_result_t *p;
-
-               if (!min || !t) {
-                       tv.tv_sec = 0;
-                       tv.tv_usec = 0;
-               } else {
-                       tv.tv_sec = t->tv_sec;
-                       tv.tv_usec = t->tv_nsec / 1000;
-               }
+       int ret;
 
-               p = aiowait(&tv);
-               if (p == (aio_result_t *) -1) {
-                       int err = errno;
-
-                       if (err == EINVAL)
-                               break;
-                       td_verror(td, err, "aiowait");
-                       break;
-               } else if (p != NULL) {
-                       io_u = container_of(p, struct io_u, resultp);
-
-                       sd->aio_events[r++] = io_u;
-                       sd->nr--;
-
-                       if (io_u->resultp.aio_return >= 0) {
-                               io_u->resid = io_u->xfer_buflen
-                                               - io_u->resultp.aio_return;
-                               io_u->error = 0;
-                       } else
-                               io_u->error = io_u->resultp.aio_return;
-               }
-       } while (r < min);
+       if (!min || !t) {
+               tv.tv_sec = 0;
+               tv.tv_usec = 0;
+       } else {
+               tv.tv_sec = t->tv_sec;
+               tv.tv_usec = t->tv_nsec / 1000;
+       }
 
-       return r;
+       while (sd->aio_pending < min)
+               wait_for_event(&tv);
+
+       /*
+        * Needs locking here for SIGIO
+        */
+       ret = sd->aio_pending;
+       sd->aio_pending = 0;
+       return ret;
 }
 
 static struct io_u *fio_solarisaio_event(struct thread_data *td, int event)
@@ -134,6 +160,22 @@ static void fio_solarisaio_cleanup(struct thread_data *td)
        }
 }
 
+/*
+ * Set USE_SIGNAL_COMPLETIONS to use SIGIO as completion events. Needs
+ * locking around ->aio_pending and ->aio_events, see comment
+ */
+static void fio_solarisaio_init_sigio(void)
+{
+#ifdef USE_SIGNAL_COMPLETIONS
+       struct sigaction act;
+
+       memset(&act, 0, sizeof(act));
+       act.sa_handler = fio_solarisaio_sigio;
+       act.sa_flags = SA_RESTART;
+       sigaction(SIGIO, &act, NULL);
+#endif
+}
+
 static int fio_solarisaio_init(struct thread_data *td)
 {
        struct solarisaio_data *sd = malloc(sizeof(*sd));
@@ -151,6 +193,8 @@ static int fio_solarisaio_init(struct thread_data *td)
        memset(sd->aio_events, 0, max_depth * sizeof(struct io_u *));
        sd->max_depth = max_depth;
 
+       fio_solarisaio_init_sigio();
+
        td->io_ops->data = sd;
        return 0;
 }

diff --git a/fio.h b/fio.h
index 25318ae52511b90d513c8c387e52b488f2e92174..9d8023706694aadb314766626ec4d40bb9c0b820 100644 (file)
--- a/fio.h
+++ b/fio.h
@@ -164,6 +164,7 @@ struct io_u {
        union {
                unsigned int index;
                unsigned int seen;
+               void *engine_data;
        };
 
        unsigned int flags;