Обсуждение: pgsql: Fix broken cleanup interlock for GIN pending list.

Fix broken cleanup interlock for GIN pending list.

The pending list must (for correctness) always be cleaned up by vacuum, and
should (for the avoidance of surprising behavior) always be cleaned up
by an explicit call to gin_clean_pending_list, but cleanup is optional
when inserting.  The old logic got this backward: cleanup was forced
if (stats == NULL), but that's going to be *false* when vacuuming and
*true* for inserts.

Masahiko Sawada, reviewed by me.

Discussion: http://postgr.es/m/CAD21AoBLUSyiYKnTYtSAbC+F=XDjiaBrOUEGK+zUXdQ8owfPKw@mail.gmail.com

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/19648ce553360852ef6a3bd32019d969144e32b6

Modified Files
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src/backend/access/gin/ginfast.c   | 14 +++++++++-----
src/backend/access/gin/ginvacuum.c |  6 +++---
src/include/access/gin_private.h   |  2 +-
3 files changed, 13 insertions(+), 9 deletions(-)