A hole in buffered vs direct I/O coherency - a buffered writer
can get data into cache between the direct write flushing the
cache and doing its own write. Actually not a real issue on Linux
due to the i_sem lock held for all writes.
Date: Wed Jun 5 08:04:30 PDT 2002
Workarea: jen.americas.sgi.com:/src/lord/xfs-linux.2.4
The following file(s) were checked into:
bonnie.engr.sgi.com:/isms/slinx/2.4.x-xfs
Modid: 2.4.x-xfs:slinx:120873a
linux/fs/xfs/xfs_rw.c - 1.357
- Use lock demote rather than unlock/relock to move from a write
to a read level of the IO lock. This closes a window where a buffered
write could get in.
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