From: Jan Kara <jack@suse.cz>
To: "zhangyi (F)" <yi.zhang@huawei.com>
Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org,
linux-block@vger.kernel.org, jack@suse.cz, tytso@mit.edu,
viro@zeniv.linux.org.uk, hch@infradead.org, axboe@kernel.dk,
mcgrof@kernel.org, keescook@chromium.org, yzaikin@google.com
Subject: Re: [RFC PATCH 1/3] block_dump: remove block_dump feature in mark_inode_dirty()
Date: Mon, 15 Mar 2021 10:47:44 +0100 [thread overview]
Message-ID: <20210315094744.GA3227@quack2.suse.cz> (raw)
In-Reply-To: <20210313030146.2882027-2-yi.zhang@huawei.com>
On Sat 13-03-21 11:01:44, zhangyi (F) wrote:
> block_dump is an old debugging interface, one of it's functions is used
> to print the information about who write which file on disk. If we
> enable block_dump through /proc/sys/vm/block_dump and turn on debug log
> level, we can gather information about write process name, target file
> name and disk from kernel message. This feature is realized in
> block_dump___mark_inode_dirty(), it print above information into kernel
> message directly when marking inode dirty, so it is noisy and can easily
> trigger log storm. At the same time, get the dentry refcount is also not
> safe, we found it will lead to deadlock on ext4 file system with
> data=journal mode.
>
> After tracepoints has been introduced into the kernel, we got a
> tracepoint in __mark_inode_dirty(), which is a better replacement of
> block_dump___mark_inode_dirty(). The only downside is that it only trace
> the inode number and not a file name, but it probably doesn't matter
> because the original printed file name in block_dump is not accurate in
> some cases, and we can still find it through the inode number and device
> id. So this patch delete the dirting inode part of block_dump feature.
>
> Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Looks good to me. Feel free to add:
Reviewed-by: Jan Kara <jack@suse.cz>
Honza
> ---
> fs/fs-writeback.c | 25 -------------------------
> 1 file changed, 25 deletions(-)
>
> diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
> index e91980f49388..7c46d1588a19 100644
> --- a/fs/fs-writeback.c
> +++ b/fs/fs-writeback.c
> @@ -2205,28 +2205,6 @@ int dirtytime_interval_handler(struct ctl_table *table, int write,
> return ret;
> }
>
> -static noinline void block_dump___mark_inode_dirty(struct inode *inode)
> -{
> - if (inode->i_ino || strcmp(inode->i_sb->s_id, "bdev")) {
> - struct dentry *dentry;
> - const char *name = "?";
> -
> - dentry = d_find_alias(inode);
> - if (dentry) {
> - spin_lock(&dentry->d_lock);
> - name = (const char *) dentry->d_name.name;
> - }
> - printk(KERN_DEBUG
> - "%s(%d): dirtied inode %lu (%s) on %s\n",
> - current->comm, task_pid_nr(current), inode->i_ino,
> - name, inode->i_sb->s_id);
> - if (dentry) {
> - spin_unlock(&dentry->d_lock);
> - dput(dentry);
> - }
> - }
> -}
> -
> /**
> * __mark_inode_dirty - internal function to mark an inode dirty
> *
> @@ -2296,9 +2274,6 @@ void __mark_inode_dirty(struct inode *inode, int flags)
> (dirtytime && (inode->i_state & I_DIRTY_INODE)))
> return;
>
> - if (unlikely(block_dump))
> - block_dump___mark_inode_dirty(inode);
> -
> spin_lock(&inode->i_lock);
> if (dirtytime && (inode->i_state & I_DIRTY_INODE))
> goto out_unlock_inode;
> --
> 2.25.4
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
next prev parent reply other threads:[~2021-03-15 9:48 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-13 3:01 [RFC PATCH 0/3] block_dump: remove block dump zhangyi (F)
2021-03-13 3:01 ` [RFC PATCH 1/3] block_dump: remove block_dump feature in mark_inode_dirty() zhangyi (F)
2021-03-15 9:47 ` Jan Kara [this message]
2021-03-13 3:01 ` [RFC PATCH 2/3] block_dump: remove block_dump feature zhangyi (F)
2021-03-15 9:48 ` Jan Kara
2021-03-13 3:01 ` [RFC PATCH 3/3] block_dump: remove comments in docs zhangyi (F)
2021-03-15 9:48 ` Jan Kara
2021-03-13 3:37 ` [RFC PATCH 0/3] block_dump: remove block dump Jens Axboe
2021-05-10 1:29 ` Zhang Yi
2021-03-15 9:56 ` Christoph Hellwig
2021-05-10 15:21 ` Jens Axboe
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=20210315094744.GA3227@quack2.suse.cz \
--to=jack@suse.cz \
--cc=axboe@kernel.dk \
--cc=hch@infradead.org \
--cc=keescook@chromium.org \
--cc=linux-block@vger.kernel.org \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=mcgrof@kernel.org \
--cc=tytso@mit.edu \
--cc=viro@zeniv.linux.org.uk \
--cc=yi.zhang@huawei.com \
--cc=yzaikin@google.com \
/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 NNTP newsgroup(s).