From: NeilBrown <neilb@suse.de>
To: Trond Myklebust <trondmy@kernel.org>, Anna Schumaker <anna@kernel.org>
Cc: linux-nfs@vger.kernel.org
Subject: [PATCH 06/11] nfs: use store_release_wake_up() for clearing d_fsdata
Date: Fri, 6 Dec 2024 13:15:32 +1100 [thread overview]
Message-ID: <20241206021830.3526922-7-neilb@suse.de> (raw)
In-Reply-To: <20241206021830.3526922-1-neilb@suse.de>
The barrier provided by smp_store_release() is before the store, while
wake_up_var() needs a full barrier *after* the store.
The new store_release_wake_up() interface encodes all the barriers
making this sort of bug harder to write.
Signed-off-by: NeilBrown <neilb@suse.de>
---
fs/nfs/dir.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 492cffd9d3d8..ded86facef8f 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1837,9 +1837,7 @@ static void block_revalidate(struct dentry *dentry)
static void unblock_revalidate(struct dentry *dentry)
{
- /* store_release ensures wait_var_event() sees the update */
- smp_store_release(&dentry->d_fsdata, NULL);
- wake_up_var(&dentry->d_fsdata);
+ store_release_wake_up(&dentry->d_fsdata, NULL);
}
/*
--
2.47.0
next prev parent reply other threads:[~2024-12-06 2:19 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-06 2:15 [PATCH 00/11] nfs: improve use of wake_up_bit and wake_up_var NeilBrown
2024-12-06 2:15 ` [PATCH 01/11] sunrpc: remove explicit barrier from rpc_make_runnable() NeilBrown
2024-12-06 2:15 ` [PATCH 02/11] sunrpc: use clear_and_wake_up_bit() for XPRT_LOCKED NeilBrown
2024-12-06 2:15 ` [PATCH 03/11] nfs: use clear_and_wake_up_bit() NeilBrown
2024-12-06 2:15 ` [PATCH 04/11] nfs: combine NFS_LAYOUT_RETURN and NFS_LAYOUT_RETURN_LOCK NeilBrown
2025-01-22 20:45 ` Mike Snitzer
2025-01-22 21:25 ` NeilBrown
2024-12-06 2:15 ` [PATCH 05/11] nfs: use clear_and_wake_up_bit() in pnfs code NeilBrown
2024-12-06 2:15 ` NeilBrown [this message]
2024-12-06 2:15 ` [PATCH 07/11] sunrpc: discard rpc_wait_bit_killable() NeilBrown
2024-12-06 2:15 ` [PATCH 08/11] nfs: discard nfs_wait_bit_killable() NeilBrown
2024-12-06 2:15 ` [PATCH 09/11] nfs: add memory barrier before calling wake_up_var on cl_state NeilBrown
2024-12-06 2:15 ` [PATCH 10/11] nfs: use atomic_dec_and_wake_up() NeilBrown
2024-12-06 2:15 ` [PATCH 11/11] nfs: use wait_var_event_spinlock() to wait for nfsi->layout to change NeilBrown
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=20241206021830.3526922-7-neilb@suse.de \
--to=neilb@suse.de \
--cc=anna@kernel.org \
--cc=linux-nfs@vger.kernel.org \
--cc=trondmy@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