[PATCH 18/43] staging/lustre/clio: generalize cl_sync_io

From: green
Date: Wed Mar 30 2016 - 12:58:52 EST


From: Jinshan Xiong <jinshan.xiong@xxxxxxxxx>

To make cl_sync_io interfaces not just wait for pages, but to be
a generic synchronization mechanism.

Also remove cl_io_cancel that became not used.

Signed-off-by: Jinshan Xiong <jinshan.xiong@xxxxxxxxx>
Reviewed-on: http://review.whamcloud.com/8656
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4198
Reviewed-by: Bobi Jam <bobijam@xxxxxxxxx>
Reviewed-by: Lai Siyao <lai.siyao@xxxxxxxxx>
Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx>
---
drivers/staging/lustre/lustre/include/cl_object.h | 13 ++--
drivers/staging/lustre/lustre/obdclass/cl_io.c | 74 +++++++++++------------
drivers/staging/lustre/lustre/obdclass/cl_page.c | 2 +-
3 files changed, 44 insertions(+), 45 deletions(-)

diff --git a/drivers/staging/lustre/lustre/include/cl_object.h b/drivers/staging/lustre/lustre/include/cl_object.h
index 69b40f5..91261b1 100644
--- a/drivers/staging/lustre/lustre/include/cl_object.h
+++ b/drivers/staging/lustre/lustre/include/cl_object.h
@@ -3125,13 +3125,18 @@ struct cl_sync_io {
atomic_t csi_barrier;
/** completion to be signaled when transfer is complete. */
wait_queue_head_t csi_waitq;
+ /** callback to invoke when this IO is finished */
+ void (*csi_end_io)(const struct lu_env *,
+ struct cl_sync_io *);
};

-void cl_sync_io_init(struct cl_sync_io *anchor, int nrpages);
-int cl_sync_io_wait(const struct lu_env *env, struct cl_io *io,
- struct cl_page_list *queue, struct cl_sync_io *anchor,
+void cl_sync_io_init(struct cl_sync_io *anchor, int nr,
+ void (*end)(const struct lu_env *, struct cl_sync_io *));
+int cl_sync_io_wait(const struct lu_env *env, struct cl_sync_io *anchor,
long timeout);
-void cl_sync_io_note(struct cl_sync_io *anchor, int ioret);
+void cl_sync_io_note(const struct lu_env *env, struct cl_sync_io *anchor,
+ int ioret);
+void cl_sync_io_end(const struct lu_env *env, struct cl_sync_io *anchor);

/** @} cl_sync_io */

diff --git a/drivers/staging/lustre/lustre/obdclass/cl_io.c b/drivers/staging/lustre/lustre/obdclass/cl_io.c
index 65d6cee..6a8dd9f 100644
--- a/drivers/staging/lustre/lustre/obdclass/cl_io.c
+++ b/drivers/staging/lustre/lustre/obdclass/cl_io.c
@@ -800,6 +800,9 @@ int cl_io_submit_rw(const struct lu_env *env, struct cl_io *io,
}
EXPORT_SYMBOL(cl_io_submit_rw);

+static void cl_page_list_assume(const struct lu_env *env,
+ struct cl_io *io, struct cl_page_list *plist);
+
/**
* Submit a sync_io and wait for the IO to be finished, or error happens.
* If \a timeout is zero, it means to wait for the IO unconditionally.
@@ -817,7 +820,7 @@ int cl_io_submit_sync(const struct lu_env *env, struct cl_io *io,
pg->cp_sync_io = anchor;
}

- cl_sync_io_init(anchor, queue->c2_qin.pl_nr);
+ cl_sync_io_init(anchor, queue->c2_qin.pl_nr, &cl_sync_io_end);
rc = cl_io_submit_rw(env, io, iot, queue);
if (rc == 0) {
/*
@@ -828,12 +831,12 @@ int cl_io_submit_sync(const struct lu_env *env, struct cl_io *io,
*/
cl_page_list_for_each(pg, &queue->c2_qin) {
pg->cp_sync_io = NULL;
- cl_sync_io_note(anchor, 1);
+ cl_sync_io_note(env, anchor, 1);
}

/* wait for the IO to be finished. */
- rc = cl_sync_io_wait(env, io, &queue->c2_qout,
- anchor, timeout);
+ rc = cl_sync_io_wait(env, anchor, timeout);
+ cl_page_list_assume(env, io, &queue->c2_qout);
} else {
LASSERT(list_empty(&queue->c2_qout.pl_pages));
cl_page_list_for_each(pg, &queue->c2_qin)
@@ -844,25 +847,6 @@ int cl_io_submit_sync(const struct lu_env *env, struct cl_io *io,
EXPORT_SYMBOL(cl_io_submit_sync);

/**
- * Cancel an IO which has been submitted by cl_io_submit_rw.
- */
-static int cl_io_cancel(const struct lu_env *env, struct cl_io *io,
- struct cl_page_list *queue)
-{
- struct cl_page *page;
- int result = 0;
-
- CERROR("Canceling ongoing page transmission\n");
- cl_page_list_for_each(page, queue) {
- int rc;
-
- rc = cl_page_cancel(env, page);
- result = result ?: rc;
- }
- return result;
-}
-
-/**
* Main io loop.
*
* Pumps io through iterations calling
@@ -1433,25 +1417,38 @@ void cl_req_attr_set(const struct lu_env *env, struct cl_req *req,
}
EXPORT_SYMBOL(cl_req_attr_set);

+/* cl_sync_io_callback assumes the caller must call cl_sync_io_wait() to
+ * wait for the IO to finish.
+ */
+void cl_sync_io_end(const struct lu_env *env, struct cl_sync_io *anchor)
+{
+ wake_up_all(&anchor->csi_waitq);
+
+ /* it's safe to nuke or reuse anchor now */
+ atomic_set(&anchor->csi_barrier, 0);
+}
+EXPORT_SYMBOL(cl_sync_io_end);

/**
- * Initialize synchronous io wait anchor, for transfer of \a nrpages pages.
+ * Initialize synchronous io wait anchor
*/
-void cl_sync_io_init(struct cl_sync_io *anchor, int nrpages)
+void cl_sync_io_init(struct cl_sync_io *anchor, int nr,
+ void (*end)(const struct lu_env *, struct cl_sync_io *))
{
init_waitqueue_head(&anchor->csi_waitq);
- atomic_set(&anchor->csi_sync_nr, nrpages);
- atomic_set(&anchor->csi_barrier, nrpages > 0);
+ atomic_set(&anchor->csi_sync_nr, nr);
+ atomic_set(&anchor->csi_barrier, nr > 0);
anchor->csi_sync_rc = 0;
+ anchor->csi_end_io = end;
+ LASSERT(end);
}
EXPORT_SYMBOL(cl_sync_io_init);

/**
- * Wait until all transfer completes. Transfer completion routine has to call
- * cl_sync_io_note() for every page.
+ * Wait until all IO completes. Transfer completion routine has to call
+ * cl_sync_io_note() for every entity.
*/
-int cl_sync_io_wait(const struct lu_env *env, struct cl_io *io,
- struct cl_page_list *queue, struct cl_sync_io *anchor,
+int cl_sync_io_wait(const struct lu_env *env, struct cl_sync_io *anchor,
long timeout)
{
struct l_wait_info lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(timeout),
@@ -1464,11 +1461,9 @@ int cl_sync_io_wait(const struct lu_env *env, struct cl_io *io,
atomic_read(&anchor->csi_sync_nr) == 0,
&lwi);
if (rc < 0) {
- CERROR("SYNC IO failed with error: %d, try to cancel %d remaining pages\n",
+ CERROR("IO failed: %d, still wait for %d remaining entries\n",
rc, atomic_read(&anchor->csi_sync_nr));

- (void)cl_io_cancel(env, io, queue);
-
lwi = (struct l_wait_info) { 0 };
(void)l_wait_event(anchor->csi_waitq,
atomic_read(&anchor->csi_sync_nr) == 0,
@@ -1477,14 +1472,12 @@ int cl_sync_io_wait(const struct lu_env *env, struct cl_io *io,
rc = anchor->csi_sync_rc;
}
LASSERT(atomic_read(&anchor->csi_sync_nr) == 0);
- cl_page_list_assume(env, io, queue);

/* wait until cl_sync_io_note() has done wakeup */
while (unlikely(atomic_read(&anchor->csi_barrier) != 0)) {
cpu_relax();
}

- POISON(anchor, 0x5a, sizeof(*anchor));
return rc;
}
EXPORT_SYMBOL(cl_sync_io_wait);
@@ -1492,7 +1485,8 @@ EXPORT_SYMBOL(cl_sync_io_wait);
/**
* Indicate that transfer of a single page completed.
*/
-void cl_sync_io_note(struct cl_sync_io *anchor, int ioret)
+void cl_sync_io_note(const struct lu_env *env, struct cl_sync_io *anchor,
+ int ioret)
{
if (anchor->csi_sync_rc == 0 && ioret < 0)
anchor->csi_sync_rc = ioret;
@@ -1503,9 +1497,9 @@ void cl_sync_io_note(struct cl_sync_io *anchor, int ioret)
*/
LASSERT(atomic_read(&anchor->csi_sync_nr) > 0);
if (atomic_dec_and_test(&anchor->csi_sync_nr)) {
- wake_up_all(&anchor->csi_waitq);
- /* it's safe to nuke or reuse anchor now */
- atomic_set(&anchor->csi_barrier, 0);
+ LASSERT(anchor->csi_end_io);
+ anchor->csi_end_io(env, anchor);
+ /* Can't access anchor any more */
}
}
EXPORT_SYMBOL(cl_sync_io_note);
diff --git a/drivers/staging/lustre/lustre/obdclass/cl_page.c b/drivers/staging/lustre/lustre/obdclass/cl_page.c
index 506a9f9..ad7f0ae 100644
--- a/drivers/staging/lustre/lustre/obdclass/cl_page.c
+++ b/drivers/staging/lustre/lustre/obdclass/cl_page.c
@@ -887,7 +887,7 @@ void cl_page_completion(const struct lu_env *env,
cl_page_put(env, pg);

if (anchor)
- cl_sync_io_note(anchor, ioret);
+ cl_sync_io_note(env, anchor, ioret);
}
EXPORT_SYMBOL(cl_page_completion);

--
2.1.0