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From: "J. Bruce Fields" <bfields@redhat.com>
To: linux-nfs@vger.kernel.org
Cc: "J. Bruce Fields" <bfields@redhat.com>
Subject: [PATCH 2/2] nfsd: note inadequate stats locking
Date: Fri, 17 May 2019 16:33:57 -0400	[thread overview]
Message-ID: <1558125237-21030-2-git-send-email-bfields@redhat.com> (raw)
In-Reply-To: <1558125237-21030-1-git-send-email-bfields@redhat.com>

From: "J. Bruce Fields" <bfields@redhat.com>

After 89a26b3d295d "nfsd: split DRC global spinlock into per-bucket
locks", there is no longer a single global spinlock to protect these
stats.

So, really we need to fix that.  For now, at least fix the comment.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/netns.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
index 4146dca94c5f..e01c22fd1485 100644
--- a/fs/nfsd/netns.h
+++ b/fs/nfsd/netns.h
@@ -144,8 +144,11 @@ struct nfsd_net {
 	unsigned int             drc_hashsize;
 
 	/*
-	 * Stats and other tracking of on the duplicate reply cache. All of these and
-	 * the "rc" fields in nfsdstats are protected by the cache_lock
+	 * Stats and other tracking of on the duplicate reply cache.
+	 * These fields and the "rc" fields in nfsdstats are modified
+	 * with only the per-bucket cache lock, which isn't really safe
+	 * and should be fixed if we want the statistics to be
+	 * completely accurate.
 	 */
 
 	/* total number of entries */
-- 
2.21.0


      reply	other threads:[~2019-05-17 20:33 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-17 20:33 [PATCH 1/2] nfsd4: drc containerization J. Bruce Fields
2019-05-17 20:33 ` J. Bruce Fields [this message]

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