From: Qu Wenruo <quwenruo.btrfs@gmx.com>
To: fdmanana@kernel.org, linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 3/3] btrfs: add and use helpers to get and set an inode's delayed_node
Date: Sat, 18 May 2024 08:21:52 +0930 [thread overview]
Message-ID: <038f89d6-3576-46c7-9336-5fde0bbc084c@gmx.com> (raw)
In-Reply-To: <48ccb776f018f79730fb9b9139623960401f9505.1715951291.git.fdmanana@suse.com>
在 2024/5/17 22:43, fdmanana@kernel.org 写道:
> From: Filipe Manana <fdmanana@suse.com>
>
> When reading the delayed_node of an inode without taking the lock of the
> root->delayed_nodes we are using READ_ONCE(), and when updating it we are
> using WRITE_ONCE().
>
> Add and use helpers that hide the usage of READ_ONCE() and WRITE_ONCE(),
> like we do for other inode fields such as first_dir_index_to_log or the
> log_transid field of struct btrfs_root for example.
>
> Also make use of the setter helper at btrfs_alloc_inode() for consistency
> only - it shouldn't be needed since when allocating an inode no one else
> can access it concurrently.
>
> Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Thanks,
Qu
> ---
> fs/btrfs/btrfs_inode.h | 12 ++++++++++++
> fs/btrfs/delayed-inode.c | 10 +++++-----
> fs/btrfs/inode.c | 4 ++--
> 3 files changed, 19 insertions(+), 7 deletions(-)
>
> diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
> index 4d9299789a03..3c8bc7a8ebdd 100644
> --- a/fs/btrfs/btrfs_inode.h
> +++ b/fs/btrfs/btrfs_inode.h
> @@ -330,6 +330,18 @@ struct btrfs_inode {
> struct inode vfs_inode;
> };
>
> +static inline struct btrfs_delayed_node *btrfs_get_inode_delayed_node(
> + const struct btrfs_inode *inode)
> +{
> + return READ_ONCE(inode->delayed_node);
> +}
> +
> +static inline void btrfs_set_inode_delayed_node(struct btrfs_inode *inode,
> + struct btrfs_delayed_node *node)
> +{
> + WRITE_ONCE(inode->delayed_node, node);
> +}
> +
> static inline u64 btrfs_get_first_dir_index_to_log(const struct btrfs_inode *inode)
> {
> return READ_ONCE(inode->first_dir_index_to_log);
> diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
> index 6df7e44d9d31..f2fe488665e8 100644
> --- a/fs/btrfs/delayed-inode.c
> +++ b/fs/btrfs/delayed-inode.c
> @@ -71,7 +71,7 @@ static struct btrfs_delayed_node *btrfs_get_delayed_node(
> u64 ino = btrfs_ino(btrfs_inode);
> struct btrfs_delayed_node *node;
>
> - node = READ_ONCE(btrfs_inode->delayed_node);
> + node = btrfs_get_inode_delayed_node(btrfs_inode);
> if (node) {
> refcount_inc(&node->refs);
> return node;
> @@ -106,7 +106,7 @@ static struct btrfs_delayed_node *btrfs_get_delayed_node(
> */
> if (refcount_inc_not_zero(&node->refs)) {
> refcount_inc(&node->refs);
> - WRITE_ONCE(btrfs_inode->delayed_node, node);
> + btrfs_set_inode_delayed_node(btrfs_inode, node);
> } else {
> node = NULL;
> }
> @@ -161,7 +161,7 @@ static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
> ASSERT(xa_err(ptr) != -EINVAL);
> ASSERT(xa_err(ptr) != -ENOMEM);
> ASSERT(ptr == NULL);
> - WRITE_ONCE(btrfs_inode->delayed_node, node);
> + btrfs_set_inode_delayed_node(btrfs_inode, node);
> xa_unlock(&root->delayed_nodes);
>
> return node;
> @@ -1308,11 +1308,11 @@ void btrfs_remove_delayed_node(struct btrfs_inode *inode)
> {
> struct btrfs_delayed_node *delayed_node;
>
> - delayed_node = READ_ONCE(inode->delayed_node);
> + delayed_node = btrfs_get_inode_delayed_node(inode);
> if (!delayed_node)
> return;
>
> - WRITE_ONCE(inode->delayed_node, NULL);
> + btrfs_set_inode_delayed_node(inode, NULL);
> btrfs_release_delayed_node(delayed_node);
> }
>
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index 11cad22d7b4c..2f3129fe0e58 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -6100,7 +6100,7 @@ static int btrfs_dirty_inode(struct btrfs_inode *inode)
> ret = btrfs_update_inode(trans, inode);
> }
> btrfs_end_transaction(trans);
> - if (READ_ONCE(inode->delayed_node))
> + if (btrfs_get_inode_delayed_node(inode))
> btrfs_balance_delayed_items(fs_info);
>
> return ret;
> @@ -8475,7 +8475,7 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
> ei->prop_compress = BTRFS_COMPRESS_NONE;
> ei->defrag_compress = BTRFS_COMPRESS_NONE;
>
> - ei->delayed_node = NULL;
> + btrfs_set_inode_delayed_node(ei, NULL);
>
> ei->i_otime_sec = 0;
> ei->i_otime_nsec = 0;
next prev parent reply other threads:[~2024-05-17 22:52 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-17 13:13 [PATCH 0/3] btrfs: avoid data races when accessing an inode's delayed_node fdmanana
2024-05-17 13:13 ` [PATCH 1/3] btrfs: always set an inode's delayed_inode with WRITE_ONCE() fdmanana
2024-05-17 22:51 ` Qu Wenruo
2024-05-17 13:13 ` [PATCH 2/3] btrfs: use READ_ONCE() when accessing delayed_node at btrfs_dirty_node() fdmanana
2024-05-17 22:51 ` Qu Wenruo
2024-05-17 13:13 ` [PATCH 3/3] btrfs: add and use helpers to get and set an inode's delayed_node fdmanana
2024-05-17 22:51 ` Qu Wenruo [this message]
2024-05-20 15:48 ` [PATCH 0/3] btrfs: avoid data races when accessing " David Sterba
2024-05-20 16:58 ` Filipe Manana
2024-05-20 20:20 ` David Sterba
2024-05-21 14:47 ` David Sterba
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=038f89d6-3576-46c7-9336-5fde0bbc084c@gmx.com \
--to=quwenruo.btrfs@gmx.com \
--cc=fdmanana@kernel.org \
--cc=linux-btrfs@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).