From: Christoph Hellwig <hch@lst.de>
Date: Tue, 20 Aug 2024 11:52:36 +0000 (+0200)
Subject: xfs: convert rtgroup lookup to an xarray
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=refs%2Fheads%2Fxfs-rtg-xarray;p=users%2Fhch%2Fxfs.git

xfs: convert rtgroup lookup to an xarray

The xarray is the modern replacement for the radix-tree.  It is simpler
to use, especially when using marks to find specific entries, something
we will heavily use for the zone allocator implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---

diff --git a/fs/xfs/libxfs/xfs_rtgroup.c b/fs/xfs/libxfs/xfs_rtgroup.c
index ec4fc961dac8..54f0e61cb789 100644
--- a/fs/xfs/libxfs/xfs_rtgroup.c
+++ b/fs/xfs/libxfs/xfs_rtgroup.c
@@ -49,7 +49,7 @@ xfs_rtgroup_get(
 	struct xfs_rtgroup	*rtg;
 
 	rcu_read_lock();
-	rtg = radix_tree_lookup(&mp->m_rtgroup_tree, rgno);
+	rtg = xa_load(&mp->m_rtgroups, rgno);
 	if (rtg) {
 		trace_xfs_rtgroup_get(rtg, _RET_IP_);
 		ASSERT(atomic_read(&rtg->rtg_ref) >= 0);
@@ -95,7 +95,7 @@ xfs_rtgroup_grab(
 	struct xfs_rtgroup	*rtg;
 
 	rcu_read_lock();
-	rtg = radix_tree_lookup(&mp->m_rtgroup_tree, agno);
+	rtg = xa_load(&mp->m_rtgroups, agno);
 	if (rtg) {
 		trace_xfs_rtgroup_grab(rtg, _RET_IP_);
 		if (!atomic_inc_not_zero(&rtg->rtg_active_ref))
@@ -128,19 +128,11 @@ xfs_rtgroup_alloc(
 	rtg->rtg_rgno = rgno;
 	rtg->rtg_mount = mp;
 
-	error = radix_tree_preload(GFP_NOFS);
-	if (error)
-		goto out_free_rtg;
-
-	spin_lock(&mp->m_rtgroup_lock);
-	if (radix_tree_insert(&mp->m_rtgroup_tree, rgno, rtg)) {
-		spin_unlock(&mp->m_rtgroup_lock);
-		radix_tree_preload_end();
-		error = -EEXIST;
+	error = xa_insert(&mp->m_rtgroups, rgno, rtg, GFP_KERNEL);
+	if (error) {
+		WARN_ON_ONCE(error == -EBUSY);
 		goto out_free_rtg;
 	}
-	spin_unlock(&mp->m_rtgroup_lock);
-	radix_tree_preload_end();
 
 #ifdef __KERNEL__
 	/* Place kernel structure only init below this point. */
@@ -166,10 +158,7 @@ xfs_rtgroup_free(
 {
 	struct xfs_rtgroup	*rtg;
 
-	spin_lock(&mp->m_rtgroup_lock);
-	rtg = radix_tree_delete(&mp->m_rtgroup_tree, rgno);
-	spin_unlock(&mp->m_rtgroup_lock);
-
+	rtg = xa_erase(&mp->m_rtgroups, rgno);
 	if (!rtg) /* can happen when growfs fails */
 		return;
 
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 360d0064da66..7f1c8775fa31 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -213,8 +213,7 @@ typedef struct xfs_mount {
 	 */
 	atomic64_t		m_allocbt_blks;
 
-	struct radix_tree_root	m_rtgroup_tree;	/* per-rt group info */
-	spinlock_t		m_rtgroup_lock;	/* lock for m_rtgroup_tree */
+	struct xarray		m_rtgroups;	/* per-rt group info */
 	struct radix_tree_root	m_perag_tree;	/* per-ag accounting info */
 	spinlock_t		m_perag_lock;	/* lock for m_perag_tree */
 	uint64_t		m_resblks;	/* total reserved blocks */
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 48d39a0c0079..4067456ab6c5 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -2031,8 +2031,7 @@ static int xfs_init_fs_context(
 	spin_lock_init(&mp->m_sb_lock);
 	INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
 	spin_lock_init(&mp->m_perag_lock);
-	INIT_RADIX_TREE(&mp->m_rtgroup_tree, GFP_ATOMIC);
-	spin_lock_init(&mp->m_rtgroup_lock);
+	xa_init(&mp->m_rtgroups);
 	mutex_init(&mp->m_growlock);
 	INIT_WORK(&mp->m_flush_inodes_work, xfs_flush_inodes_worker);
 	INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);