pgsql: Improve commentary in timeout.c. - Mailing list pgsql-committers

Improve commentary in timeout.c.

On re-reading I realized that I'd missed one race condition in the new
timeout code.  It's safe, but add a comment explaining it.

Discussion: https://postgr.es/m/CA+hUKG+o6pbuHBJSGnud=TadsuXySWA7CCcPgCt2QE9F6_4iHQ@mail.gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/9486e7b666fd113f043d5f091fd42bc1ef72acd8

Modified Files
--------------
src/backend/utils/misc/timeout.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)