[XFS] Clean up dquot pincount code.
This is a code cleanup and optimization that removes a per mount point
spinlock from the quota code and cleans up the code.
The patch changes the pincount from being an int protected by a spinlock
to an atomic_t allowing the pincount to be manipulated without holding the
spinlock.
This cleanup also protects against random wakup's of both the aild and
xfssyncd by reevaluating the pincount after been woken. Two latter patches
will address the Spurious wakeups.
SGI-PV: 986789
SGI-Modid: xfs-linux-melb:xfs-kern:32215a
Signed-off-by: Peter Leckie <pleckie@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
diff --git a/fs/xfs/quota/xfs_dquot.h b/fs/xfs/quota/xfs_dquot.h
index 8958d0f..7e455337 100644
--- a/fs/xfs/quota/xfs_dquot.h
+++ b/fs/xfs/quota/xfs_dquot.h
@@ -83,8 +83,8 @@
xfs_qcnt_t q_res_rtbcount;/* total realtime blks used+reserved */
mutex_t q_qlock; /* quota lock */
struct completion q_flush; /* flush completion queue */
- uint q_pincount; /* pin count for this dquot */
- sv_t q_pinwait; /* sync var for pinning */
+ atomic_t q_pincount; /* dquot pin count */
+ wait_queue_head_t q_pinwait; /* dquot pinning wait queue */
#ifdef XFS_DQUOT_TRACE
struct ktrace *q_trace; /* trace header structure */
#endif