From: Al Viro <viro@zeniv.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org
Subject: Re: [PATCH][RFC] make take_dentry_name_snapshot() lockless
Date: Tue, 10 Dec 2024 02:45:23 +0000 [thread overview]
Message-ID: <20241210024523.GD3387508@ZenIV> (raw)
In-Reply-To: <20241209231237.GC3387508@ZenIV>
On Mon, Dec 09, 2024 at 11:12:37PM +0000, Al Viro wrote:
>
> Actually, grepping for DNAME_INLINE_LEN brings some interesting hits:
> drivers/net/ieee802154/adf7242.c:1165: char debugfs_dir_name[DNAME_INLINE_LEN + 1];
> cargo-culted, AFAICS; would be better off with a constant of their own.
>
> fs/ext4/fast_commit.c:326: fc_dentry->fcd_name.len > DNAME_INLINE_LEN)
> fs/ext4/fast_commit.c:452: if (dentry->d_name.len > DNAME_INLINE_LEN) {
> fs/ext4/fast_commit.c:1332: fc_dentry->fcd_name.len > DNAME_INLINE_LEN)
> fs/ext4/fast_commit.h:113: unsigned char fcd_iname[DNAME_INLINE_LEN]; /* Dirent name string */
> Looks like that might want struct name_snapshot, along with
> {take,release}_dentry_name_snapshot().
See viro/vfs.git#work.dcache. I've thrown ext4/fast_commit conversion
into the end of that pile. NOTE: that stuff obviously needs profiling.
It does survive light testing (boot/ltp/xfstests), but review and more
testing (including serious profiling) is obviously needed.
Patches in followups...
next prev parent reply other threads:[~2024-12-10 2:45 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-09 3:52 [PATCH][RFC] make take_dentry_name_snapshot() lockless Al Viro
2024-12-09 6:33 ` Mateusz Guzik
2024-12-09 6:58 ` Al Viro
2024-12-09 7:18 ` Mateusz Guzik
2024-12-09 7:41 ` Al Viro
2024-12-09 18:27 ` Linus Torvalds
2024-12-09 21:17 ` Al Viro
2024-12-09 22:28 ` Al Viro
2024-12-09 22:49 ` Linus Torvalds
2024-12-09 22:55 ` Linus Torvalds
2024-12-09 23:12 ` Al Viro
2024-12-10 2:45 ` Al Viro [this message]
2024-12-10 2:48 ` [PATCH 1/5] make sure that DCACHE_INLINE_LEN is a multiple of word size Al Viro
2024-12-10 2:48 ` [PATCH 2/5] dcache: back inline names with a struct-wrapped array of unsigned long Al Viro
2024-12-10 2:48 ` [PATCH 3/5] make take_dentry_name_snapshot() lockless Al Viro
2024-12-10 2:48 ` [PATCH 4/5] dissolve external_name.u into separate members Al Viro
2024-12-10 2:48 ` [PATCH 5/5] ext4 fast_commit: make use of name_snapshot primitives Al Viro
2024-12-23 4:25 ` [PATCH][RFC] make take_dentry_name_snapshot() lockless Al Viro
2024-12-23 4:37 ` Al Viro
2024-12-23 21:31 ` Jens Axboe
2024-12-24 19:18 ` Al Viro
2024-12-24 19:44 ` Linus Torvalds
2024-12-24 20:24 ` Al Viro
2024-12-09 19:06 ` Linus Torvalds
2024-12-09 20:27 ` Al Viro
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=20241210024523.GD3387508@ZenIV \
--to=viro@zeniv.linux.org.uk \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=torvalds@linux-foundation.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