* [PATCH 1/2] fixup: btrfs: add tracking of read blocks for read policy
2025-01-08 21:01 [PATCH 0/2] btrfs: migrate tracking read blocks from fs_devices to Anand Jain
@ 2025-01-08 21:01 ` Anand Jain
2025-01-08 21:01 ` [PATCH 2/2] fixup: btrfs: introduce RAID1 round-robin read balancing Anand Jain
2025-01-09 10:17 ` [PATCH 0/2] btrfs: migrate tracking read blocks from fs_devices to David Sterba
2 siblings, 0 replies; 4+ messages in thread
From: Anand Jain @ 2025-01-08 21:01 UTC (permalink / raw)
To: linux-btrfs, dsterba
Move stats_read_blocks from btrfs_fs_devices to btrfs_fs_info and its
init and destroy.
This is based on the `for-next` branch in the repo github.com/btrfs/linux.git.
Fixes: 49136a74162e btrfs: add tracking of read blocks for read policy
Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
fs/btrfs/bio.c | 2 +-
fs/btrfs/disk-io.c | 5 +++++
fs/btrfs/fs.h | 3 +++
fs/btrfs/volumes.c | 6 ------
fs/btrfs/volumes.h | 3 ---
5 files changed, 9 insertions(+), 10 deletions(-)
diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c
index afff205ef671..bc2555c44a12 100644
--- a/fs/btrfs/bio.c
+++ b/fs/btrfs/bio.c
@@ -458,7 +458,7 @@ static void btrfs_submit_dev_bio(struct btrfs_device *dev, struct bio *bio)
* filesystem is fully initialized.
*/
if (dev->fs_devices->collect_fs_stats && bio_op(bio) == REQ_OP_READ && dev->fs_info)
- percpu_counter_add(&dev->fs_devices->stats_read_blocks,
+ percpu_counter_add(&dev->fs_info->stats_read_blocks,
bio->bi_iter.bi_size >> dev->fs_info->sectorsize_bits);
if (bio->bi_opf & REQ_BTRFS_CGROUP_PUNT)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 4928bf2cd07f..ef3121b55c50 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1258,6 +1258,7 @@ void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
{
struct percpu_counter *em_counter = &fs_info->evictable_extent_maps;
+ percpu_counter_destroy(&fs_info->stats_read_blocks);
percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
percpu_counter_destroy(&fs_info->delalloc_bytes);
percpu_counter_destroy(&fs_info->ordered_bytes);
@@ -2923,6 +2924,10 @@ static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block
if (ret)
return ret;
+ ret = percpu_counter_init(&fs_info->stats_read_blocks, 0, GFP_KERNEL);
+ if (ret)
+ return ret;
+
fs_info->dirty_metadata_batch = PAGE_SIZE *
(1 + ilog2(nr_cpu_ids));
diff --git a/fs/btrfs/fs.h b/fs/btrfs/fs.h
index be8c32d1a7bb..b572d6b9730b 100644
--- a/fs/btrfs/fs.h
+++ b/fs/btrfs/fs.h
@@ -627,6 +627,9 @@ struct btrfs_fs_info {
struct kobject *qgroups_kobj;
struct kobject *discard_kobj;
+ /* Track the number of blocks (sectors) read by the filesystem. */
+ struct percpu_counter stats_read_blocks;
+
/* Used to keep from writing metadata until there is a nice batch */
struct percpu_counter dirty_metadata_bytes;
struct percpu_counter delalloc_bytes;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index c02d551b73a7..e0c64246f8f6 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1255,7 +1255,6 @@ static void close_fs_devices(struct btrfs_fs_devices *fs_devices)
list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list)
btrfs_close_one_device(device);
- percpu_counter_destroy(&fs_devices->stats_read_blocks);
WARN_ON(fs_devices->open_devices);
WARN_ON(fs_devices->rw_devices);
fs_devices->opened = 0;
@@ -1303,11 +1302,6 @@ static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
s64 __maybe_unused value = 0;
int ret = 0;
- /* Initialize the in-memory record of filesystem read count. */
- ret = percpu_counter_init(&fs_devices->stats_read_blocks, 0, GFP_KERNEL);
- if (ret)
- return ret;
-
list_for_each_entry_safe(device, tmp_device, &fs_devices->devices,
dev_list) {
int ret2;
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index f197e152f318..120f65e21eeb 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -438,9 +438,6 @@ struct btrfs_fs_devices {
enum btrfs_chunk_allocation_policy chunk_alloc_policy;
- /* Track the number of blocks (sectors) read by the filesystem. */
- struct percpu_counter stats_read_blocks;
-
/* Policy used to read the mirrored stripes. */
enum btrfs_read_policy read_policy;
--
2.47.0
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH 2/2] fixup: btrfs: introduce RAID1 round-robin read balancing
2025-01-08 21:01 [PATCH 0/2] btrfs: migrate tracking read blocks from fs_devices to Anand Jain
2025-01-08 21:01 ` [PATCH 1/2] fixup: btrfs: add tracking of read blocks for read policy Anand Jain
@ 2025-01-08 21:01 ` Anand Jain
2025-01-09 10:17 ` [PATCH 0/2] btrfs: migrate tracking read blocks from fs_devices to David Sterba
2 siblings, 0 replies; 4+ messages in thread
From: Anand Jain @ 2025-01-08 21:01 UTC (permalink / raw)
To: linux-btrfs, dsterba
The member stats_read_blocks has been moved to fs_info, so update its
usage accordingly in btrfs_read_rr().
This is based on the `for-next` branch in the repo github.com/btrfs/linux.git.
Fixes: ee37a901a9d2 btrfs: introduce RAID1 round-robin read balancing
Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
fs/btrfs/volumes.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index e0c64246f8f6..a594f66daedf 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6018,21 +6018,22 @@ static int btrfs_read_rr(const struct btrfs_chunk_map *map, int first, int num_s
{
struct stripe_mirror stripes[BTRFS_RAID1_MAX_MIRRORS] = { 0 };
struct btrfs_device *device = map->stripes[first].dev;
- struct btrfs_fs_devices *fs_devices = device->fs_devices;
+ struct btrfs_fs_info *fs_info = device->fs_devices->fs_info;
unsigned int read_cycle;
unsigned int total_reads;
unsigned int min_reads_per_dev;
- total_reads = percpu_counter_sum(&fs_devices->stats_read_blocks);
- min_reads_per_dev = READ_ONCE(fs_devices->rr_min_contig_read) >>
- fs_devices->fs_info->sectorsize_bits;
+ total_reads = percpu_counter_sum(&fs_info->stats_read_blocks);
+ min_reads_per_dev = READ_ONCE(fs_info->fs_devices->rr_min_contig_read) >>
+ fs_info->sectorsize_bits;
for (int index = 0, i = first; i < first + num_stripes; i++) {
stripes[index].devid = map->stripes[i].dev->devid;
stripes[index].num = i;
index++;
}
- sort(stripes, num_stripes, sizeof(struct stripe_mirror), btrfs_cmp_devid, NULL);
+ sort(stripes, num_stripes, sizeof(struct stripe_mirror),
+ btrfs_cmp_devid, NULL);
read_cycle = total_reads / min_reads_per_dev;
return stripes[read_cycle % num_stripes].num;
--
2.47.0
^ permalink raw reply related [flat|nested] 4+ messages in thread