Commit 0c842ad4 authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

xfs: clean up buffer locking helpers 



Rename xfs_buf_cond_lock and reverse it's return value to fit most other
trylock operations in the Kernel and XFS (with the exception of down_trylock,
after which xfs_buf_cond_lock was modelled), and replace xfs_buf_lock_val
with an xfs_buf_islocked for use in asserts, or and opencoded variant in
tracing.  remove the XFS_BUF_* wrappers for all the locking helpers.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarAlex Elder <aelder@sgi.com>
Reviewed-by: default avatarDave Chinner <dchinner@redhat.com>
parent bbb4197c

fs/xfs/linux-2.6/xfs_buf.c

+11 −20
Original line number Diff line number Diff line
@@ -499,16 +499,14 @@ found: 
	spin_unlock(&pag->pag_buf_lock);

	xfs_perag_put(pag);



	if (xfs_buf_cond_lock(bp)) {

		/* failed, so wait for the lock if requested. */

		if (!(flags & XBF_TRYLOCK)) {

			xfs_buf_lock(bp);

			XFS_STATS_INC(xb_get_locked_waited);

		} else {

	if (!xfs_buf_trylock(bp)) {

		if (flags & XBF_TRYLOCK) {

			xfs_buf_rele(bp);

			XFS_STATS_INC(xb_busy_locked);

			return NULL;

		}

		xfs_buf_lock(bp);

		XFS_STATS_INC(xb_get_locked_waited);

	}



	/*
@@ -896,8 +894,8 @@ xfs_buf_rele( 
 *	to push on stale inode buffers.

 */

int

xfs_buf_cond_lock(

	xfs_buf_t		*bp)

xfs_buf_trylock(

	struct xfs_buf		*bp)

{

	int			locked;
@@ -907,15 +905,8 @@ xfs_buf_cond_lock( 
	else if (atomic_read(&bp->b_pin_count) && (bp->b_flags & XBF_STALE))

		xfs_log_force(bp->b_target->bt_mount, 0);



	trace_xfs_buf_cond_lock(bp, _RET_IP_);

	return locked ? 0 : -EBUSY;

}



int

xfs_buf_lock_value(

	xfs_buf_t		*bp)

{

	return bp->b_sema.count;

	trace_xfs_buf_trylock(bp, _RET_IP_);

	return locked;

}



/*
@@ -929,7 +920,7 @@ xfs_buf_lock_value( 
 */

void

xfs_buf_lock(

	xfs_buf_t		*bp)

	struct xfs_buf		*bp)

{

	trace_xfs_buf_lock(bp, _RET_IP_);
@@ -950,7 +941,7 @@ xfs_buf_lock( 
 */

void

xfs_buf_unlock(

	xfs_buf_t		*bp)

	struct xfs_buf		*bp)

{

	if ((bp->b_flags & (XBF_DELWRI|_XBF_DELWRI_Q)) == XBF_DELWRI) {

		atomic_inc(&bp->b_hold);
@@ -1694,7 +1685,7 @@ xfs_buf_delwri_split( 
	list_for_each_entry_safe(bp, n, dwq, b_list) {

		ASSERT(bp->b_flags & XBF_DELWRI);



		if (!XFS_BUF_ISPINNED(bp) && !xfs_buf_cond_lock(bp)) {

		if (!XFS_BUF_ISPINNED(bp) && xfs_buf_trylock(bp)) {

			if (!force &&

			    time_before(jiffies, bp->b_queuetime + age)) {

				xfs_buf_unlock(bp);

fs/xfs/linux-2.6/xfs_buf.h

+3 −6
Original line number Diff line number Diff line
@@ -187,10 +187,11 @@ extern void xfs_buf_free(xfs_buf_t *); 
extern void xfs_buf_rele(xfs_buf_t *);



/* Locking and Unlocking Buffers */

extern int xfs_buf_cond_lock(xfs_buf_t *);

extern int xfs_buf_lock_value(xfs_buf_t *);

extern int xfs_buf_trylock(xfs_buf_t *);

extern void xfs_buf_lock(xfs_buf_t *);

extern void xfs_buf_unlock(xfs_buf_t *);

#define xfs_buf_islocked(bp) \

	((bp)->b_sema.count <= 0)



/* Buffer Read and Write Routines */

extern int xfs_bwrite(struct xfs_mount *mp, struct xfs_buf *bp);
@@ -308,10 +309,6 @@ xfs_buf_set_ref( 


#define XFS_BUF_ISPINNED(bp)	atomic_read(&((bp)->b_pin_count))



#define XFS_BUF_VALUSEMA(bp)	xfs_buf_lock_value(bp)

#define XFS_BUF_CPSEMA(bp)	(xfs_buf_cond_lock(bp) == 0)

#define XFS_BUF_VSEMA(bp)	xfs_buf_unlock(bp)

#define XFS_BUF_PSEMA(bp,x)	xfs_buf_lock(bp)

#define XFS_BUF_FINISH_IOWAIT(bp)	complete(&bp->b_iowait);



#define XFS_BUF_SET_TARGET(bp, target)	((bp)->b_target = (target))

fs/xfs/linux-2.6/xfs_trace.h

+5 −5
Original line number Diff line number Diff line
@@ -293,7 +293,7 @@ DECLARE_EVENT_CLASS(xfs_buf_class, 
		__entry->buffer_length = bp->b_buffer_length;

		__entry->hold = atomic_read(&bp->b_hold);

		__entry->pincount = atomic_read(&bp->b_pin_count);

		__entry->lockval = xfs_buf_lock_value(bp);

		__entry->lockval = bp->b_sema.count;

		__entry->flags = bp->b_flags;

		__entry->caller_ip = caller_ip;

	),
@@ -323,7 +323,7 @@ DEFINE_BUF_EVENT(xfs_buf_bawrite); 
DEFINE_BUF_EVENT(xfs_buf_bdwrite);

DEFINE_BUF_EVENT(xfs_buf_lock);

DEFINE_BUF_EVENT(xfs_buf_lock_done);

DEFINE_BUF_EVENT(xfs_buf_cond_lock);

DEFINE_BUF_EVENT(xfs_buf_trylock);

DEFINE_BUF_EVENT(xfs_buf_unlock);

DEFINE_BUF_EVENT(xfs_buf_iowait);

DEFINE_BUF_EVENT(xfs_buf_iowait_done);
@@ -366,7 +366,7 @@ DECLARE_EVENT_CLASS(xfs_buf_flags_class, 
		__entry->flags = flags;

		__entry->hold = atomic_read(&bp->b_hold);

		__entry->pincount = atomic_read(&bp->b_pin_count);

		__entry->lockval = xfs_buf_lock_value(bp);

		__entry->lockval = bp->b_sema.count;

		__entry->caller_ip = caller_ip;

	),

	TP_printk("dev %d:%d bno 0x%llx len 0x%zx hold %d pincount %d "
@@ -409,7 +409,7 @@ TRACE_EVENT(xfs_buf_ioerror, 
		__entry->buffer_length = bp->b_buffer_length;

		__entry->hold = atomic_read(&bp->b_hold);

		__entry->pincount = atomic_read(&bp->b_pin_count);

		__entry->lockval = xfs_buf_lock_value(bp);

		__entry->lockval = bp->b_sema.count;

		__entry->error = error;

		__entry->flags = bp->b_flags;

		__entry->caller_ip = caller_ip;
@@ -454,7 +454,7 @@ DECLARE_EVENT_CLASS(xfs_buf_item_class, 
		__entry->buf_flags = bip->bli_buf->b_flags;

		__entry->buf_hold = atomic_read(&bip->bli_buf->b_hold);

		__entry->buf_pincount = atomic_read(&bip->bli_buf->b_pin_count);

		__entry->buf_lockval = xfs_buf_lock_value(bip->bli_buf);

		__entry->buf_lockval = bip->bli_buf->b_sema.count;

		__entry->li_desc = bip->bli_item.li_desc;

		__entry->li_flags = bip->bli_item.li_flags;

	),

fs/xfs/quota/xfs_dquot.c

+3 −3
Original line number Diff line number Diff line
@@ -318,7 +318,7 @@ xfs_qm_init_dquot_blk( 


	ASSERT(tp);

	ASSERT(XFS_BUF_ISBUSY(bp));

	ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);

	ASSERT(xfs_buf_islocked(bp));



	d = (xfs_dqblk_t *)XFS_BUF_PTR(bp);
@@ -534,7 +534,7 @@ xfs_qm_dqtobp( 
	}



	ASSERT(XFS_BUF_ISBUSY(bp));

	ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);

	ASSERT(xfs_buf_islocked(bp));



	/*

	 * calculate the location of the dquot inside the buffer.
@@ -622,7 +622,7 @@ xfs_qm_dqread( 
	 * brelse it because we have the changes incore.

	 */

	ASSERT(XFS_BUF_ISBUSY(bp));

	ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);

	ASSERT(xfs_buf_islocked(bp));

	xfs_trans_brelse(tp, bp);



	return (error);

fs/xfs/xfs_buf_item.c

+3 −3
Original line number Diff line number Diff line
@@ -420,7 +420,7 @@ xfs_buf_item_unpin( 


	if (freed && stale) {

		ASSERT(bip->bli_flags & XFS_BLI_STALE);

		ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);

		ASSERT(xfs_buf_islocked(bp));

		ASSERT(!(XFS_BUF_ISDELAYWRITE(bp)));

		ASSERT(XFS_BUF_ISSTALE(bp));

		ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL);
@@ -483,7 +483,7 @@ xfs_buf_item_trylock( 


	if (XFS_BUF_ISPINNED(bp))

		return XFS_ITEM_PINNED;

	if (!XFS_BUF_CPSEMA(bp))

	if (!xfs_buf_trylock(bp))

		return XFS_ITEM_LOCKED;



	/* take a reference to the buffer.  */
@@ -905,7 +905,7 @@ xfs_buf_attach_iodone( 
	xfs_log_item_t	*head_lip;



	ASSERT(XFS_BUF_ISBUSY(bp));

	ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);

	ASSERT(xfs_buf_islocked(bp));



	lip->li_cb = cb;

	if (XFS_BUF_FSPRIVATE(bp, void *) != NULL) {

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