Обсуждение: pgsql: Use LW_SHARED in walsummarizer.c for WALSummarizerLock lock wher

Use LW_SHARED in walsummarizer.c for WALSummarizerLock lock where possible.

Previously, we used LW_EXCLUSIVE in several places despite only reading
WalSummarizerCtl fields. This patch reduces the lock level to LW_SHARED
where we are only reading the shared fields.

Backpatch to 17, where wal summarization was introduced.

Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/CAD21AoDdKhf_9oriEYxY-JCdF+Oe_muhca3pcdkMEdBMzyHyKw@mail.gmail.com
Backpatch-through: 17

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/fabd8b8e2a72bac9e5a361856a355bd5bb2e61b8

Modified Files
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src/backend/postmaster/walsummarizer.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)