[XFS] Convert l_flushsema to a sv_t
The l_flushsema doesn't exactly have completion semantics, nor mutex
semantics. It's used as a list of tasks which are waiting to be notified
that a flush has completed. It was also being used in a way that was
potentially racy, depending on the semaphore implementation.
By using a sv_t instead of a semaphore we avoid the need for a separate
counter, since we know we just need to wake everything on the queue.
Original waitqueue implementation from Matthew Wilcox. Cleanup and
conversion to sv_t by Christoph Hellwig.
SGI-PV: 981507
SGI-Modid: xfs-linux-melb:xfs-kern:31059a
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h
index 8952a39..6245913 100644
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -423,10 +423,8 @@
int l_logBBsize; /* size of log in BB chunks */
/* The following block of fields are changed while holding icloglock */
- sema_t l_flushsema ____cacheline_aligned_in_smp;
- /* iclog flushing semaphore */
- int l_flushcnt; /* # of procs waiting on this
- * sema */
+ sv_t l_flush_wait ____cacheline_aligned_in_smp;
+ /* waiting for iclog flush */
int l_covered_state;/* state of "covering disk
* log entries" */
xlog_in_core_t *l_iclog; /* head log queue */
