Thread: pgsql: Base LWLock limits directly on MAX_BACKENDS
Base LWLock limits directly on MAX_BACKENDS Jacob reported that comments for LW_SHARED_MASK referenced a MAX_BACKENDS limit of 2^23-1, but that MAX_BACKENDS is actually limited to 2^18-1. The limit was lowered in 48354581a49c, but the comment in lwlock.c wasn't updated. Instead of just fixing the comment, it seems better to directly base the lwlock defines on MAX_BACKENDS and add static assertions to ensure that there is enough space. That way there's no comment that can go out of sync in the future. As part of that change I noticed that for some reason the high bit wasn't used for flags, which seems somewhat odd. Redefine the flag values to start at the highest bit. Reported-by: Jacob Brazeal <jacob.brazeal@gmail.com> Reviewed-by: Jacob Brazeal <jacob.brazeal@gmail.com> Discussion: https://postgr.es/m/CA+COZaBO_s3LfALq=b+HcBHFSOEGiApVjrRacCe4VP9m7CJsNQ@mail.gmail.com Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/cd3ccf88aacb43b7232d6834dc886ff8538c6ce8 Modified Files -------------- src/backend/storage/lmgr/lwlock.c | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-)