[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240122094536.198454-3-libaokun1@huawei.com>
Date: Mon, 22 Jan 2024 17:45:36 +0800
From: Baokun Li <libaokun1@...wei.com>
To: <linux-fsdevel@...r.kernel.org>
CC: <torvalds@...ux-foundation.org>, <viro@...iv.linux.org.uk>,
<brauner@...nel.org>, <jack@...e.cz>, <willy@...radead.org>,
<akpm@...ux-foundation.org>, <linux-kernel@...r.kernel.org>,
<yi.zhang@...wei.com>, <yangerkun@...wei.com>, <yukuai3@...wei.com>,
<libaokun1@...wei.com>
Subject: [PATCH 2/2] Revert "mm/filemap: avoid buffered read/write race to read inconsistent data"
This reverts commit e2c27b803bb6 ("mm/filemap: avoid buffered read/write
race to read inconsistent data"). After making the i_size_read/write
helpers be smp_load_acquire/store_release(), it is already guaranteed that
changes to page contents are visible before we see increased inode size,
so the extra smp_rmb() in filemap_read() can be removed.
Signed-off-by: Baokun Li <libaokun1@...wei.com>
---
mm/filemap.c | 9 ---------
1 file changed, 9 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index 142864338ca4..bed844b07e87 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2608,15 +2608,6 @@ ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *iter,
goto put_folios;
end_offset = min_t(loff_t, isize, iocb->ki_pos + iter->count);
- /*
- * Pairs with a barrier in
- * block_write_end()->mark_buffer_dirty() or other page
- * dirtying routines like iomap_write_end() to ensure
- * changes to page contents are visible before we see
- * increased inode size.
- */
- smp_rmb();
-
/*
* Once we start copying data, we don't want to be touching any
* cachelines that might be contended:
--
2.31.1
Powered by blists - more mailing lists