pg_upgrade failed for 9.0 to 9.2

Hi,

When I was upgrading database from 9.0 to 9.2 using pg_upgrade, I got the
error:

CREATE VIEW stats_slowest_queries AS
SELECT pg_stat_activity.procpid, (('now'::text)::timestamp(6) with time
zone - pg_stat_activity.query_start) AS execution_time,
pg_stat_activity.current_query FROM pg_stat_activity WHERE
(pg_stat_activity.current_query !~~ '<IDLE%'::text) ORDER BY
(('now'::text)::timestamp(6) with time zone - pg_stat_activity.query_start)
DESC;
psql:pg_upgrade_dump_db.sql:498897: ERROR: column pg_stat_activity.procpid
does not exist
LINE 2: SELECT pg_stat_activity.procpid, (('now'::text)::timesta...
^
It failed.

Could you let me know why?

Thanks.