Thread: pgsql: Skip extraneous locking in XLogCheckBuffer().

Skip extraneous locking in XLogCheckBuffer().
Heikki reported comment was wrong, so fixed
code to match the comment: we only need to
take additional locking precautions when we
have a shared lock on the buffer.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/5787c6730e7a848ef95d5c4194e27614ea8e6e41

Modified Files
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src/backend/access/transam/xlog.c |   27 ++++++++++++++++-----------
1 files changed, 16 insertions(+), 11 deletions(-)