From 0c6e75175bcaf8d05bfa88aa8caa584fbb848b74 Mon Sep 17 00:00:00 2001
From: Jens Axboe <jens.axboe@oracle.com>
Date: Thu, 22 Feb 2007 11:19:39 +0100
Subject: [PATCH] Track io_u state (free or in-flight)

That way we can catch proper use by fio, so we don't get stuck
in cleanup_pending_aio() if someone forgot to put_io_u() in an
error path.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 fio.c       | 15 +++++++++++++--
 fio.h       |  7 +++++++
 io_u.c      | 10 ++++++++++
 ioengines.c |  4 ++++
 4 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/fio.c b/fio.c
index 9594f805..0ccd5d85 100644
--- a/fio.c
+++ b/fio.c
@@ -160,9 +160,19 @@ static void cleanup_pending_aio(struct thread_data *td)
 		list_for_each_safe(entry, n, &td->io_u_busylist) {
 			io_u = list_entry(entry, struct io_u, list);
 
-			r = td->io_ops->cancel(td, io_u);
-			if (!r)
+			/*
+			 * if the io_u isn't in flight, then that generally
+			 * means someone leaked an io_u. complain but fix
+			 * it up, so we don't stall here.
+			 */
+			if ((io_u->flags & IO_U_F_FLIGHT) == 0) {
+				log_err("fio: non-busy IO on busy list\n");
 				put_io_u(td, io_u);
+			} else {
+				r = td->io_ops->cancel(td, io_u);
+				if (!r)
+					put_io_u(td, io_u);
+			}
 		}
 	}
 
@@ -553,6 +563,7 @@ static int init_io_u(struct thread_data *td)
 			fill_rand_buf(io_u, max_bs);
 
 		io_u->index = i;
+		io_u->flags = IO_U_F_FREE;
 		list_add(&io_u->list, &td->io_u_freelist);
 	}
 
diff --git a/fio.h b/fio.h
index aeb45bf7..c168fe70 100644
--- a/fio.h
+++ b/fio.h
@@ -76,6 +76,11 @@ struct syslet_req {
 };
 #endif
 
+enum {
+	IO_U_F_FREE	= 1 << 0,
+	IO_U_F_FLIGHT	= 1 << 1,
+};
+
 /*
  * The io unit
  */
@@ -124,6 +129,8 @@ struct io_u {
 		unsigned int seen;
 	};
 
+	unsigned int flags;
+
 	struct fio_file *file;
 
 	struct list_head list;
diff --git a/io_u.c b/io_u.c
index 23a64b04..d30ff4b3 100644
--- a/io_u.c
+++ b/io_u.c
@@ -3,6 +3,7 @@
 #include <string.h>
 #include <signal.h>
 #include <time.h>
+#include <assert.h>
 
 #include "fio.h"
 #include "os.h"
@@ -193,6 +194,9 @@ static enum fio_ddir get_rw_ddir(struct thread_data *td)
 
 void put_io_u(struct thread_data *td, struct io_u *io_u)
 {
+	assert((io_u->flags & IO_U_F_FREE) == 0);
+	io_u->flags |= IO_U_F_FREE;
+
 	io_u->file = NULL;
 	list_del(&io_u->list);
 	list_add(&io_u->list, &td->io_u_freelist);
@@ -352,6 +356,9 @@ struct io_u *__get_io_u(struct thread_data *td)
 	}
 
 	if (io_u) {
+		assert(io_u->flags & IO_U_F_FREE);
+		io_u->flags &= ~IO_U_F_FREE;
+
 		io_u->error = 0;
 		list_del(&io_u->list);
 		list_add(&io_u->list, &td->io_u_busylist);
@@ -441,6 +448,9 @@ static void io_completed(struct thread_data *td, struct io_u *io_u,
 {
 	unsigned long msec;
 
+	assert(io_u->flags & IO_U_F_FLIGHT);
+	io_u->flags &= ~IO_U_F_FLIGHT;
+
 	if (io_u->ddir == DDIR_SYNC) {
 		td->last_was_sync = 1;
 		return;
diff --git a/ioengines.c b/ioengines.c
index ab5b2245..17044187 100644
--- a/ioengines.c
+++ b/ioengines.c
@@ -14,6 +14,7 @@
 #include <unistd.h>
 #include <string.h>
 #include <dlfcn.h>
+#include <assert.h>
 
 #include "fio.h"
 #include "os.h"
@@ -188,6 +189,9 @@ int td_io_queue(struct thread_data *td, struct io_u *io_u)
 {
 	int ret;
 
+	assert((io_u->flags & IO_U_F_FLIGHT) == 0);
+	io_u->flags |= IO_U_F_FLIGHT;
+
 	if (td->io_ops->flags & FIO_SYNCIO)
 		fio_gettime(&io_u->issue_time, NULL);
 
-- 
2.25.1