pgsql: Avoid unnecessary shared invalidations in ROLLBACK PREPARED

Avoid unnecessary shared invalidations in ROLLBACK PREPARED

The performance gain is minimal, but this makes the logic more
consistent with AtEOXact_Inval().  No other invalidation is needed in
this case as PREPARE takes already care of sending any local ones.

Author: Liu Huailing
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/OSZPR01MB6215AA84D71EF2B3D354CF86BE139@OSZPR01MB6215.jpnprd01.prod.outlook.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/710796f0542180cca18ee93889da692df642bdf2

Modified Files
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src/backend/access/transam/twophase.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)