From: Matthew Wilcox <willy@infradead.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-fsdevel@vger.kernel.org, torvalds@linux-foundation.org,
viro@zeniv.linux.org.uk
Subject: Re: [PATCH 2/4] fs: add support for LOOKUP_NONBLOCK
Date: Tue, 15 Dec 2020 12:24:47 +0000 [thread overview]
Message-ID: <20201215122447.GQ2443@casper.infradead.org> (raw)
In-Reply-To: <20201214191323.173773-3-axboe@kernel.dk>
On Mon, Dec 14, 2020 at 12:13:22PM -0700, Jens Axboe wrote:
> +++ b/fs/namei.c
> @@ -686,6 +686,8 @@ static bool try_to_unlazy(struct nameidata *nd)
> BUG_ON(!(nd->flags & LOOKUP_RCU));
>
> nd->flags &= ~LOOKUP_RCU;
> + if (nd->flags & LOOKUP_NONBLOCK)
> + goto out1;
If we try a walk in a non-blocking context, it fails, then we punt to
a thread, do we want to prohibit that thread trying an RCU walk first?
I can see arguments both ways -- this may only be a temporary RCU walk
failure, or we may never be able to RCU walk this path.
next prev parent reply other threads:[~2020-12-15 12:25 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-14 19:13 [PATCHSET v3 0/4] fs: Support for LOOKUP_NONBLOCK / RESOLVE_NONBLOCK Jens Axboe
2020-12-14 19:13 ` [PATCH 1/4] fs: make unlazy_walk() error handling consistent Jens Axboe
2020-12-14 19:13 ` [PATCH 2/4] fs: add support for LOOKUP_NONBLOCK Jens Axboe
2020-12-15 12:24 ` Matthew Wilcox [this message]
2020-12-15 15:29 ` Jens Axboe
2020-12-15 15:33 ` Matthew Wilcox
2020-12-15 15:37 ` Jens Axboe
2020-12-15 16:08 ` Jens Axboe
2020-12-15 16:14 ` Jens Axboe
2020-12-15 18:29 ` Linus Torvalds
2020-12-15 18:44 ` Jens Axboe
2020-12-15 18:47 ` Linus Torvalds
2020-12-15 19:03 ` Jens Axboe
2020-12-15 19:32 ` Linus Torvalds
2020-12-15 19:38 ` Jens Axboe
2020-12-16 2:36 ` Al Viro
2020-12-16 3:30 ` Jens Axboe
2020-12-16 2:43 ` Al Viro
2020-12-16 3:32 ` Jens Axboe
2020-12-14 19:13 ` [PATCH 3/4] fs: expose LOOKUP_NONBLOCK through openat2() RESOLVE_NONBLOCK Jens Axboe
2020-12-15 22:25 ` Dave Chinner
2020-12-15 22:31 ` Linus Torvalds
2020-12-15 23:25 ` Jens Axboe
2020-12-16 2:37 ` Al Viro
2020-12-16 3:39 ` Linus Torvalds
2020-12-14 19:13 ` [PATCH 4/4] io_uring: enable LOOKUP_NONBLOCK path resolution for filename lookups Jens Axboe
2020-12-15 3:06 ` [PATCHSET v3 0/4] fs: Support for LOOKUP_NONBLOCK / RESOLVE_NONBLOCK Linus Torvalds
2020-12-15 3:18 ` Jens Axboe
2020-12-15 6:11 ` Al Viro
2020-12-15 15:29 ` Jens Axboe
2021-01-04 5:31 ` Al Viro
2021-01-04 14:43 ` Jens Axboe
2021-01-04 16:54 ` Al Viro
2021-01-04 17:03 ` Jens Axboe
[not found] ` <m1lfbrwrgq.fsf@fess.ebiederm.org>
2021-02-14 16:38 ` [PATCHSET v3 0/4] fs: Support for LOOKUP_NONBLOCK / RESOLVE_NONBLOCK (Insufficiently faking current?) Jens Axboe
2021-02-14 20:30 ` Linus Torvalds
2021-02-14 21:24 ` Al Viro
2021-02-15 18:07 ` Eric W. Biederman
2021-02-15 18:24 ` Jens Axboe
2021-02-15 21:09 ` Jens Axboe
2021-02-15 22:41 ` Eric W. Biederman
2021-02-16 2:41 ` Jens Axboe
2021-02-17 1:18 ` Jens Axboe
2021-02-17 1:26 ` Jens Axboe
2021-02-17 3:11 ` Jens Axboe
2021-02-15 17:56 ` Eric W. Biederman
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