[PATCH 05/11] sched/wait,btrfs: Replace wait_on_atomic_t usage

From: Peter Zijlstra
Date: Thu Mar 15 2018 - 08:36:24 EST


Convert the wait_on_atomic_t() usage to the new wait_var_event() API.

Cc: Chris Mason <clm@xxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
fs/btrfs/extent-tree.c | 14 ++++++--------
fs/btrfs/ioctl.c | 2 +-
2 files changed, 7 insertions(+), 9 deletions(-)

--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3990,7 +3990,7 @@ void btrfs_dec_nocow_writers(struct btrf
bg = btrfs_lookup_block_group(fs_info, bytenr);
ASSERT(bg);
if (atomic_dec_and_test(&bg->nocow_writers))
- wake_up_atomic_t(&bg->nocow_writers);
+ wake_up_var(&bg->nocow_writers);
/*
* Once for our lookup and once for the lookup done by a previous call
* to btrfs_inc_nocow_writers()
@@ -4001,8 +4001,7 @@ void btrfs_dec_nocow_writers(struct btrf

void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)
{
- wait_on_atomic_t(&bg->nocow_writers, atomic_t_wait,
- TASK_UNINTERRUPTIBLE);
+ wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));
}

static const char *alloc_name(u64 flags)
@@ -6526,7 +6525,7 @@ void btrfs_dec_block_group_reservations(
bg = btrfs_lookup_block_group(fs_info, start);
ASSERT(bg);
if (atomic_dec_and_test(&bg->reservations))
- wake_up_atomic_t(&bg->reservations);
+ wake_up_var(&bg->reservations);
btrfs_put_block_group(bg);
}

@@ -6552,8 +6551,7 @@ void btrfs_wait_block_group_reservations
down_write(&space_info->groups_sem);
up_write(&space_info->groups_sem);

- wait_on_atomic_t(&bg->reservations, atomic_t_wait,
- TASK_UNINTERRUPTIBLE);
+ wait_var_event(&bg->reservations, !atomic_read(&bg->reservations));
}

/**
@@ -11061,7 +11059,7 @@ void btrfs_wait_for_snapshot_creation(st
ret = btrfs_start_write_no_snapshotting(root);
if (ret)
break;
- wait_on_atomic_t(&root->will_be_snapshotted, atomic_t_wait,
- TASK_UNINTERRUPTIBLE);
+ wait_var_event(&root->will_be_snapshotted,
+ !atomic_read(&root->will_be_snapshotted));
}
}
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -723,7 +723,7 @@ static int create_snapshot(struct btrfs_
btrfs_subvolume_release_metadata(fs_info, &pending_snapshot->block_rsv);
dec_and_free:
if (atomic_dec_and_test(&root->will_be_snapshotted))
- wake_up_atomic_t(&root->will_be_snapshotted);
+ wake_up_var(&root->will_be_snapshotted);
free_pending:
kfree(pending_snapshot->root_item);
btrfs_free_path(pending_snapshot->path);