pgsql: spinlock emulation: Fix bug when more than INT_MAX spinlocks are

spinlock emulation: Fix bug when more than INT_MAX spinlocks are initialized.

Once the counter goes negative we ended up with spinlocks that errored
out on first use (due to check in tas_sema).

Author: Andres Freund
Reviewed-By: Robert Haas
Discussion: https://postgr.es/m/20200606023103.avzrctgv7476xj7i@alap3.anarazel.de
Backpatch: 9.5-

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/660622053419fbb776c7218f2110500b3b034b35

Modified Files
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src/backend/storage/lmgr/spin.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)