xfs: parallelize block preallocation garbage collection

Split the block preallocation garbage collection work into per-AG work
items so that we can take advantage of parallelization.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

1 files changed, 30 insertions, 12 deletions

diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 35c735514565..460fa7b3a31c 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -1333,12 +1333,12 @@ xfs_inode_free_eofblocks(
  */
 static inline void
 xfs_blockgc_queue(
-	struct xfs_mount	*mp)
+	struct xfs_perag	*pag)
 {
 	rcu_read_lock();
-	if (radix_tree_tagged(&mp->m_perag_tree, XFS_ICI_BLOCKGC_TAG))
-		queue_delayed_work(mp->m_blockgc_workqueue,
-				   &mp->m_blockgc_work,
+	if (radix_tree_tagged(&pag->pag_ici_root, XFS_ICI_BLOCKGC_TAG))
+		queue_delayed_work(pag->pag_mount->m_blockgc_workqueue,
+				   &pag->pag_blockgc_work,
 				   msecs_to_jiffies(xfs_blockgc_secs * 1000));
 	rcu_read_unlock();
 }
@@ -1380,7 +1380,7 @@ xfs_blockgc_set_iflag(
 		spin_unlock(&ip->i_mount->m_perag_lock);
 
 		/* kick off background trimming */
-		xfs_blockgc_queue(ip->i_mount);
+		xfs_blockgc_queue(pag);
 
 		trace_xfs_perag_set_blockgc(ip->i_mount, pag->pag_agno, -1,
 				_RET_IP_);
@@ -1555,12 +1555,24 @@ xfs_inode_clear_cowblocks_tag(
 	return xfs_blockgc_clear_iflag(ip, XFS_ICOWBLOCKS);
 }
 
+#define for_each_perag_tag(mp, next_agno, pag, tag) \
+	for ((next_agno) = 0, (pag) = xfs_perag_get_tag((mp), 0, (tag)); \
+		(pag) != NULL; \
+		(next_agno) = (pag)->pag_agno + 1, \
+		xfs_perag_put(pag), \
+		(pag) = xfs_perag_get_tag((mp), (next_agno), (tag)))
+
+
 /* Disable post-EOF and CoW block auto-reclamation. */
 void
 xfs_blockgc_stop(
 	struct xfs_mount	*mp)
 {
-	cancel_delayed_work_sync(&mp->m_blockgc_work);
+	struct xfs_perag	*pag;
+	xfs_agnumber_t		agno;
+
+	for_each_perag_tag(mp, agno, pag, XFS_ICI_BLOCKGC_TAG)
+		cancel_delayed_work_sync(&pag->pag_blockgc_work);
 }
 
 /* Enable post-EOF and CoW block auto-reclamation. */
@@ -1568,7 +1580,11 @@ void
 xfs_blockgc_start(
 	struct xfs_mount	*mp)
 {
-	xfs_blockgc_queue(mp);
+	struct xfs_perag	*pag;
+	xfs_agnumber_t		agno;
+
+	for_each_perag_tag(mp, agno, pag, XFS_ICI_BLOCKGC_TAG)
+		xfs_blockgc_queue(pag);
 }
 
 /* Scan one incore inode for block preallocations that we can remove. */
@@ -1595,18 +1611,20 @@ void
 xfs_blockgc_worker(
 	struct work_struct	*work)
 {
-	struct xfs_mount	*mp = container_of(to_delayed_work(work),
-					struct xfs_mount, m_blockgc_work);
+	struct xfs_perag	*pag = container_of(to_delayed_work(work),
+					struct xfs_perag, pag_blockgc_work);
+	struct xfs_mount	*mp = pag->pag_mount;
 	int			error;
 
 	if (!sb_start_write_trylock(mp->m_super))
 		return;
-	error = xfs_inode_walk(mp, 0, xfs_blockgc_scan_inode, NULL,
+	error = xfs_inode_walk_ag(pag, 0, xfs_blockgc_scan_inode, NULL,
 			XFS_ICI_BLOCKGC_TAG);
 	if (error)
-		xfs_info(mp, "preallocation gc worker failed, err=%d", error);
+		xfs_info(mp, "AG %u preallocation gc worker failed, err=%d",
+				pag->pag_agno, error);
 	sb_end_write(mp->m_super);
-	xfs_blockgc_queue(mp);
+	xfs_blockgc_queue(pag);
 }
 
 /*