From: Al Viro <viro@zeniv.linux.org.uk>
To: Max Kellermann <max.kellermann@ionos.com>
Cc: linux-fsdevel@vger.kernel.org,
Christian Brauner <brauner@kernel.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 20/21] __dentry_kill(): new locking scheme
Date: Mon, 7 Jul 2025 21:49:18 +0100 [thread overview]
Message-ID: <20250707204918.GK1880847@ZenIV> (raw)
In-Reply-To: <CAKPOu+8kLwwG4aKiArX2pKq-jroTgq0MSWW2AC1SjO-G9O_Aog@mail.gmail.com>
On Mon, Jul 07, 2025 at 10:39:27PM +0200, Max Kellermann wrote:
> > Busy loop here means that everything in the tree is either busy or already
> > in process of being torn down *by* *another* *thread*. And that's already
> > in process - not just selected for it (see collect2 in the same loop).
>
> The busy process isn't doing anything. All it does is busy-wait for
> another task to complete the evict() call. A pointless waste of CPU
> cycles.
>
> > The interesting question is what the other thread is doing...
>
> ceph_evict_inode() is waiting for the Ceph server to acknowledge a
> pending I/O operation.
Yes, but where does that ceph_evict_inode() come from? What's in its call chain?
Is it several shrink_dcache_parent() fighting each other on the same tree, or...?
next prev parent reply other threads:[~2025-07-07 20:49 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-24 6:02 [RFC][PATCHSET v3] simplifying fast_dput(), dentry_kill() et.al Al Viro
2023-11-24 6:04 ` [PATCH v3 01/21] switch nfsd_client_rmdir() to use of simple_recursive_removal() Al Viro
2023-11-24 6:04 ` [PATCH v3 02/21] coda_flag_children(): cope with dentries turning negative Al Viro
2023-11-24 21:22 ` Linus Torvalds
2023-11-24 22:58 ` Paul E. McKenney
2023-11-24 6:04 ` [PATCH v3 03/21] dentry: switch the lists of children to hlist Al Viro
2023-11-24 7:44 ` Amir Goldstein
2023-11-24 7:55 ` Al Viro
2023-11-24 8:02 ` Amir Goldstein
2023-11-24 6:04 ` [PATCH v3 04/21] centralize killing dentry from shrink list Al Viro
2023-11-24 6:04 ` [PATCH v3 05/21] shrink_dentry_list(): no need to check that dentry refcount is marked dead Al Viro
2023-11-24 6:04 ` [PATCH v3 06/21] fast_dput(): having ->d_delete() is not reason to delay refcount decrement Al Viro
2023-11-24 6:04 ` [PATCH v3 07/21] fast_dput(): handle underflows gracefully Al Viro
2023-11-24 6:04 ` [PATCH v3 08/21] fast_dput(): new rules for refcount Al Viro
2023-11-24 6:04 ` [PATCH v3 09/21] __dput_to_list(): do decrement of refcount in the callers Al Viro
2023-11-24 6:04 ` [PATCH v3 10/21] make retain_dentry() neutral with respect to refcounting Al Viro
2023-11-24 6:04 ` [PATCH v3 11/21] __dentry_kill(): get consistent rules for victim's refcount Al Viro
2023-11-24 6:04 ` [PATCH v3 12/21] dentry_kill(): don't bother with retain_dentry() on slow path Al Viro
2023-11-24 6:04 ` [PATCH v3 13/21] Call retain_dentry() with refcount 0 Al Viro
2023-11-24 6:04 ` [PATCH v3 14/21] fold the call of retain_dentry() into fast_dput() Al Viro
2023-11-24 6:04 ` [PATCH v3 15/21] don't try to cut corners in shrink_lock_dentry() Al Viro
2023-11-24 6:04 ` [PATCH v3 16/21] fold dentry_kill() into dput() Al Viro
2023-11-24 6:04 ` [PATCH v3 17/21] to_shrink_list(): call only if refcount is 0 Al Viro
2023-11-24 6:04 ` [PATCH v3 18/21] switch select_collect{,2}() to use of to_shrink_list() Al Viro
2023-11-24 6:04 ` [PATCH v3 19/21] d_prune_aliases(): use a shrink list Al Viro
2023-11-24 6:04 ` [PATCH v3 20/21] __dentry_kill(): new locking scheme Al Viro
2025-07-07 17:20 ` Max Kellermann
2025-07-07 17:29 ` Al Viro
2025-07-07 17:43 ` Max Kellermann
2025-07-07 18:00 ` Al Viro
2025-07-07 18:11 ` Max Kellermann
2025-07-07 19:31 ` Al Viro
2025-07-07 20:00 ` Max Kellermann
2025-07-07 20:31 ` Al Viro
2025-07-07 20:39 ` Max Kellermann
2025-07-07 20:49 ` Al Viro [this message]
2025-07-07 20:52 ` Max Kellermann
2025-07-07 20:59 ` Al Viro
2025-07-07 21:06 ` Max Kellermann
2025-07-07 21:32 ` Al Viro
2025-07-07 21:47 ` Max Kellermann
2025-07-07 22:19 ` Al Viro
2025-07-07 22:37 ` Al Viro
2025-07-08 4:45 ` Max Kellermann
2025-07-07 22:26 ` Al Viro
2023-11-24 6:04 ` [PATCH v3 21/21] retain_dentry(): introduce a trimmed-down lockless variant Al Viro
2023-11-24 21:28 ` [RFC][PATCHSET v3] simplifying fast_dput(), dentry_kill() et.al Linus Torvalds
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