[PATCH 1/6] staging: lustre: libcfs: move add_wait_queue_exclusive_head to lustre layer

From: James Simmons
Date: Thu Mar 31 2016 - 10:21:00 EST


Only lustre client uses add_wait_queue_exclusive_head() so move
it from libcfs layer to lustre_lib.h where it is needed.

Signed-off-by: James Simmons <uja.ornl@xxxxxxxxx>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6245
Reviewed-on: http://review.whamcloud.com/13874
Reviewed-by: Dmitry Eremin <dmitry.eremin@xxxxxxxxx>
Reviewed-by: John L. Hammond <john.hammond@xxxxxxxxx>
Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx>
---
.../lustre/include/linux/libcfs/libcfs_prim.h | 2 -
.../staging/lustre/lnet/libcfs/linux/linux-prim.c | 24 --------------------
drivers/staging/lustre/lustre/include/lustre_lib.h | 22 ++++++++++++++++++
3 files changed, 22 insertions(+), 26 deletions(-)

diff --git a/drivers/staging/lustre/include/linux/libcfs/libcfs_prim.h b/drivers/staging/lustre/include/linux/libcfs/libcfs_prim.h
index 082fe6d..d7846e8 100644
--- a/drivers/staging/lustre/include/linux/libcfs/libcfs_prim.h
+++ b/drivers/staging/lustre/include/linux/libcfs/libcfs_prim.h
@@ -40,8 +40,6 @@
#ifndef __LIBCFS_PRIM_H__
#define __LIBCFS_PRIM_H__

-void add_wait_queue_exclusive_head(wait_queue_head_t *, wait_queue_t *);
-
/*
* Memory
*/
diff --git a/drivers/staging/lustre/lnet/libcfs/linux/linux-prim.c b/drivers/staging/lustre/lnet/libcfs/linux/linux-prim.c
index 7e5ef0a..bbe19a6 100644
--- a/drivers/staging/lustre/lnet/libcfs/linux/linux-prim.c
+++ b/drivers/staging/lustre/lnet/libcfs/linux/linux-prim.c
@@ -46,30 +46,6 @@
#include <linux/kgdb.h>
#endif

-/**
- * wait_queue_t of Linux (version < 2.6.34) is a FIFO list for exclusively
- * waiting threads, which is not always desirable because all threads will
- * be waken up again and again, even user only needs a few of them to be
- * active most time. This is not good for performance because cache can
- * be polluted by different threads.
- *
- * LIFO list can resolve this problem because we always wakeup the most
- * recent active thread by default.
- *
- * NB: please don't call non-exclusive & exclusive wait on the same
- * waitq if add_wait_queue_exclusive_head is used.
- */
-void
-add_wait_queue_exclusive_head(wait_queue_head_t *waitq, wait_queue_t *link)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&waitq->lock, flags);
- __add_wait_queue_exclusive(waitq, link);
- spin_unlock_irqrestore(&waitq->lock, flags);
-}
-EXPORT_SYMBOL(add_wait_queue_exclusive_head);
-
sigset_t
cfs_block_allsigs(void)
{
diff --git a/drivers/staging/lustre/lustre/include/lustre_lib.h b/drivers/staging/lustre/lustre/include/lustre_lib.h
index 2e66b27..00b9767 100644
--- a/drivers/staging/lustre/lustre/include/lustre_lib.h
+++ b/drivers/staging/lustre/lustre/include/lustre_lib.h
@@ -522,6 +522,28 @@ struct l_wait_info {
sigmask(SIGTERM) | sigmask(SIGQUIT) | \
sigmask(SIGALRM))

+/**
+ * wait_queue_t of Linux (version < 2.6.34) is a FIFO list for exclusively
+ * waiting threads, which is not always desirable because all threads will
+ * be waken up again and again, even user only needs a few of them to be
+ * active most time. This is not good for performance because cache can
+ * be polluted by different threads.
+ *
+ * LIFO list can resolve this problem because we always wakeup the most
+ * recent active thread by default.
+ *
+ * NB: please don't call non-exclusive & exclusive wait on the same
+ * waitq if add_wait_queue_exclusive_head is used.
+ */
+#define add_wait_queue_exclusive_head(waitq, link) \
+{ \
+ unsigned long flags; \
+ \
+ spin_lock_irqsave(&((waitq)->lock), flags); \
+ __add_wait_queue_exclusive(waitq, link); \
+ spin_unlock_irqrestore(&((waitq)->lock), flags); \
+}
+
/*
* wait for @condition to become true, but no longer than timeout, specified
* by @info.
--
1.7.1