From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
Rename reada_tree to reada_array. Use the xa_lock in reada_array to
replace reada_lock. This has to use a nested spinlock as we take the
xa_lock of the reada_extents and reada_zones xarrays while holding
the reada_lock.
Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
fs/btrfs/ctree.h | 15 +++++--
fs/btrfs/disk-io.c | 3 +-
fs/btrfs/reada.c | 119 +++++++++++++++++++++++++----------------------------
3 files changed, 70 insertions(+), 67 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 173d72dfaab6..272d099bed7e 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1052,9 +1052,8 @@ struct btrfs_fs_info {
struct btrfs_delayed_root *delayed_root;
- /* readahead tree */
- spinlock_t reada_lock;
- struct radix_tree_root reada_tree;
+ /* readahead extents */
+ struct xarray reada_array;
/* readahead works cnt */
atomic_t reada_works_cnt;
@@ -1102,6 +1101,16 @@ struct btrfs_fs_info {
#endif
};
+static inline void reada_lock(struct btrfs_fs_info *fs_info)
+{
+ spin_lock_nested(&fs_info->reada_array.xa_lock, SINGLE_DEPTH_NESTING);
+}
+
+static inline void reada_unlock(struct btrfs_fs_info *fs_info)
+{
+ spin_unlock(&fs_info->reada_array.xa_lock);
+}
+
static inline struct btrfs_fs_info *btrfs_sb(struct super_block *sb)
{
return sb->s_fs_info;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 62995a55d112..1eae29045d43 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2478,8 +2478,7 @@ int open_ctree(struct super_block *sb,
fs_info->commit_interval = BTRFS_DEFAULT_COMMIT_INTERVAL;
fs_info->avg_delayed_ref_runtime = NSEC_PER_SEC >> 6; /* div by 64 */
/* readahead state */
- INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
- spin_lock_init(&fs_info->reada_lock);
+ xa_init(&fs_info->reada_array);
btrfs_init_ref_verify(fs_info);
fs_info->thread_pool_size = min_t(unsigned long,
diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c
index 8100f1565250..89ba0063903f 100644
--- a/fs/btrfs/reada.c
+++ b/fs/btrfs/reada.c
@@ -215,12 +215,11 @@ int btree_readahead_hook(struct extent_buffer *eb, int err)
struct reada_extent *re;
/* find extent */
- spin_lock(&fs_info->reada_lock);
- re = radix_tree_lookup(&fs_info->reada_tree,
- eb->start >> PAGE_SHIFT);
+ reada_lock(fs_info);
+ re = xa_load(&fs_info->reada_array, eb->start >> PAGE_SHIFT);
if (re)
re->refcnt++;
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
if (!re) {
ret = -1;
goto start_machine;
@@ -246,15 +245,15 @@ static struct reada_zone *reada_find_zone(struct btrfs_device *dev, u64 logical,
unsigned long index = logical >> PAGE_SHIFT;
int i;
- spin_lock(&fs_info->reada_lock);
+ reada_lock(fs_info);
zone = xa_find(&dev->reada_zones, &index, ULONG_MAX, XA_PRESENT);
if (zone && logical >= zone->start && logical <= zone->end) {
kref_get(&zone->refcnt);
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
return zone;
}
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
cache = btrfs_lookup_block_group(fs_info, logical);
if (!cache)
@@ -289,7 +288,7 @@ static struct reada_zone *reada_find_zone(struct btrfs_device *dev, u64 logical,
}
zone->ndevs = bbio->num_stripes;
- spin_lock(&fs_info->reada_lock);
+ reada_lock(fs_info);
curr = xa_cmpxchg(&dev->reada_zones,
(unsigned long)(zone->end >> PAGE_SHIFT),
NULL, zone, GFP_NOWAIT | __GFP_NOWARN);
@@ -301,7 +300,7 @@ static struct reada_zone *reada_find_zone(struct btrfs_device *dev, u64 logical,
else
zone = NULL;
}
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
return zone;
}
@@ -323,11 +322,11 @@ static struct reada_extent *reada_find_extent(struct btrfs_fs_info *fs_info,
int dev_replace_is_ongoing;
int have_zone = 0;
- spin_lock(&fs_info->reada_lock);
- re = radix_tree_lookup(&fs_info->reada_tree, index);
+ reada_lock(fs_info);
+ re = xa_load(&fs_info->reada_array, index);
if (re)
re->refcnt++;
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
if (re)
return re;
@@ -378,38 +377,32 @@ static struct reada_extent *reada_find_extent(struct btrfs_fs_info *fs_info,
kref_get(&zone->refcnt);
++zone->elems;
spin_unlock(&zone->lock);
- spin_lock(&fs_info->reada_lock);
+ reada_lock(fs_info);
kref_put(&zone->refcnt, reada_zone_release);
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
}
if (re->nzones == 0) {
/* not a single zone found, error and out */
goto error;
}
- ret = radix_tree_preload(GFP_KERNEL);
- if (ret)
- goto error;
-
- /* insert extent in reada_tree + all per-device trees, all or nothing */
+ /*
+ * Insert extent in reada_array and all per-device arrays,
+ * all or nothing
+ */
btrfs_dev_replace_lock(&fs_info->dev_replace, 0);
- spin_lock(&fs_info->reada_lock);
- ret = radix_tree_insert(&fs_info->reada_tree, index, re);
- if (ret == -EEXIST) {
- re_exist = radix_tree_lookup(&fs_info->reada_tree, index);
- re_exist->refcnt++;
- spin_unlock(&fs_info->reada_lock);
- btrfs_dev_replace_unlock(&fs_info->dev_replace, 0);
- radix_tree_preload_end();
- goto error;
- }
- if (ret) {
- spin_unlock(&fs_info->reada_lock);
+ reada_lock(fs_info);
+ re_exist = __xa_cmpxchg(&fs_info->reada_array, index, NULL, re,
+ GFP_KERNEL);
+ if (re_exist) {
+ if (xa_is_err(re_exist))
+ re_exist = NULL;
+ else
+ re_exist->refcnt++;
+ reada_unlock(fs_info);
btrfs_dev_replace_unlock(&fs_info->dev_replace, 0);
- radix_tree_preload_end();
goto error;
}
- radix_tree_preload_end();
prev_dev = NULL;
dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(
&fs_info->dev_replace);
@@ -447,14 +440,14 @@ static struct reada_extent *reada_find_extent(struct btrfs_fs_info *fs_info,
/* ignore whether the entry was inserted */
xa_erase(&dev->reada_extents, index);
}
- radix_tree_delete(&fs_info->reada_tree, index);
- spin_unlock(&fs_info->reada_lock);
+ __xa_erase(&fs_info->reada_array, index);
+ reada_unlock(fs_info);
btrfs_dev_replace_unlock(&fs_info->dev_replace, 0);
goto error;
}
have_zone = 1;
}
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
btrfs_dev_replace_unlock(&fs_info->dev_replace, 0);
if (!have_zone)
@@ -473,16 +466,16 @@ static struct reada_extent *reada_find_extent(struct btrfs_fs_info *fs_info,
--zone->elems;
if (zone->elems == 0) {
/*
- * no fs_info->reada_lock needed, as this can't be
- * the last ref
+ * no fs_info->reada_array lock needed, as this
+ * can't be the last ref
*/
kref_put(&zone->refcnt, reada_zone_release);
}
spin_unlock(&zone->lock);
- spin_lock(&fs_info->reada_lock);
+ reada_lock(fs_info);
kref_put(&zone->refcnt, reada_zone_release);
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
}
btrfs_put_bbio(bbio);
kfree(re);
@@ -495,20 +488,20 @@ static void reada_extent_put(struct btrfs_fs_info *fs_info,
int i;
unsigned long index = re->logical >> PAGE_SHIFT;
- spin_lock(&fs_info->reada_lock);
+ reada_lock(fs_info);
if (--re->refcnt) {
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
return;
}
- radix_tree_delete(&fs_info->reada_tree, index);
+ __xa_erase(&fs_info->reada_array, index);
for (i = 0; i < re->nzones; ++i) {
struct reada_zone *zone = re->zones[i];
xa_erase(&zone->device->reada_extents, index);
}
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
for (i = 0; i < re->nzones; ++i) {
struct reada_zone *zone = re->zones[i];
@@ -517,15 +510,17 @@ static void reada_extent_put(struct btrfs_fs_info *fs_info,
spin_lock(&zone->lock);
--zone->elems;
if (zone->elems == 0) {
- /* no fs_info->reada_lock needed, as this can't be
- * the last ref */
+ /*
+ * no fs_info->reada_array lock needed, as this
+ * can't be the last ref
+ */
kref_put(&zone->refcnt, reada_zone_release);
}
spin_unlock(&zone->lock);
- spin_lock(&fs_info->reada_lock);
+ reada_lock(fs_info);
kref_put(&zone->refcnt, reada_zone_release);
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
}
kfree(re);
@@ -579,7 +574,7 @@ static int reada_add_block(struct reada_control *rc, u64 logical,
}
/*
- * called with fs_info->reada_lock held
+ * called with fs_info->reada_array lock held
*/
static void reada_peer_zones_set_lock(struct reada_zone *zone, int lock)
{
@@ -595,7 +590,7 @@ static void reada_peer_zones_set_lock(struct reada_zone *zone, int lock)
}
/*
- * called with fs_info->reada_lock held
+ * called with fs_info->reada_array lock held
*/
static int reada_pick_zone(struct btrfs_device *dev)
{
@@ -649,11 +644,11 @@ static int reada_start_machine_dev(struct btrfs_device *dev)
int ret;
int i;
- spin_lock(&fs_info->reada_lock);
+ reada_lock(fs_info);
if (dev->reada_curr_zone == NULL) {
ret = reada_pick_zone(dev);
if (!ret) {
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
return 0;
}
}
@@ -667,7 +662,7 @@ static int reada_start_machine_dev(struct btrfs_device *dev)
if (!re || re->logical > dev->reada_curr_zone->end) {
ret = reada_pick_zone(dev);
if (!ret) {
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
return 0;
}
index = dev->reada_next >> PAGE_SHIFT;
@@ -675,13 +670,13 @@ static int reada_start_machine_dev(struct btrfs_device *dev)
XA_PRESENT);
}
if (!re) {
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
return 0;
}
dev->reada_next = re->logical + fs_info->nodesize;
re->refcnt++;
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
spin_lock(&re->lock);
if (re->scheduled || list_empty(&re->extctl)) {
@@ -806,7 +801,7 @@ static void dump_devs(struct btrfs_fs_info *fs_info, int all)
int j;
int cnt;
- spin_lock(&fs_info->reada_lock);
+ reada_lock(fs_info);
list_for_each_entry(device, &fs_devices->devices, dev_list) {
struct reada_zone *zone;
@@ -859,11 +854,11 @@ static void dump_devs(struct btrfs_fs_info *fs_info, int all)
index = 0;
cnt = 0;
while (all) {
- struct reada_extent *re = NULL;
+ struct reada_extent *re;
- ret = radix_tree_gang_lookup(&fs_info->reada_tree, (void **)&re,
- index, 1);
- if (ret == 0)
+ re = xa_find(&fs_info->reada_tree, &index, ULONG_MAX,
+ XA_PRESENT);
+ if (!re)
break;
if (!re->scheduled) {
index = (re->logical >> PAGE_SHIFT) + 1;
@@ -882,9 +877,9 @@ static void dump_devs(struct btrfs_fs_info *fs_info, int all)
}
}
pr_cont("\n");
- index = (re->logical >> PAGE_SHIFT) + 1;
+ index++;
}
- spin_unlock(&fs_info->reada_lock);
+ reada_unlock(fs_info);
}
#endif
--
2.15.1
--
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