diff options
| author | Anand Jain <anand.jain@oracle.com> | 2020-09-05 01:34:30 +0800 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2020-10-07 12:12:22 +0200 |
| commit | 2fca0db07608a303dbe9db802ecca678e358dca9 (patch) | |
| tree | 86eee6ef3563eb031520513468d6b2b8d91e4420 /fs/btrfs/reada.c | |
| parent | 7ad3912a70a696197d03856749f89dad7a377bc9 (diff) | |
| download | linux-2fca0db07608a303dbe9db802ecca678e358dca9.tar.bz2 | |
btrfs: reada: lock all seed/sprout devices in __reada_start_machine
On an fs mounted using a sprout device, the seed fs_devices are
maintained in a linked list under fs_info->fs_devices. Each seeds
fs_devices also has device_list_mutex initialized to protect against the
potential race with delete threads. But the delete thread (at
btrfs_rm_device()) is holding the fs_info::fs_devices::device_list_mutex
mutex which belongs to sprout device_list_mutex instead of seed
device_list_mutex. Moreover, there aren't any significient benefits in
using the seed::device_list_mutex instead of sprout::device_list_mutex.
So this patch converts them of using the seed::device_list_mutex to
sprout::device_list_mutex.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/reada.c')
| -rw-r--r-- | fs/btrfs/reada.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c index e20972230823..9d4f5316a7e8 100644 --- a/fs/btrfs/reada.c +++ b/fs/btrfs/reada.c @@ -776,13 +776,11 @@ static int reada_start_for_fsdevs(struct btrfs_fs_devices *fs_devices) do { enqueued = 0; - mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry(device, &fs_devices->devices, dev_list) { if (atomic_read(&device->reada_in_flight) < MAX_IN_FLIGHT) enqueued += reada_start_machine_dev(device); } - mutex_unlock(&fs_devices->device_list_mutex); total += enqueued; } while (enqueued && total < 10000); @@ -795,10 +793,13 @@ static void __reada_start_machine(struct btrfs_fs_info *fs_info) int i; u64 enqueued = 0; + mutex_lock(&fs_devices->device_list_mutex); + enqueued += reada_start_for_fsdevs(fs_devices); list_for_each_entry(seed_devs, &fs_devices->seed_list, seed_list) enqueued += reada_start_for_fsdevs(seed_devs); + mutex_unlock(&fs_devices->device_list_mutex); if (enqueued == 0) return; |