Fix backend state after a failed after-startup shmem request
RegisterShmemCallbacks() left the backend in a bad state, if an error
occurred in the callbacks or if an allocation failed. Firstly,
'shmem_request_state' was left in wrong state, causing a subsequent
call to RegisterShmemCallbacks() to wrongly take the postmaster
startup codepath or assertion failures in some other functions.
Secondly, the 'pending_shmem_requests' list was not properly cleaned
up, causing a subsequent RegisterShmemCallbacks() to try to process
the stale, already-freed requests.
To fix, add a PG_TRY() block to clean those things up on error.
Author: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://www.postgresql.org/message-id/CAJTYsWVRRWH48=PcuAo_2Y4Ap6M0QRmzxgUfFkNRtdWK74LjBQ@mail.gmail.com
Backpatch-through: 19
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/c54b6979e033c6182518d4b33feb35771ae738ae
Modified Files
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src/backend/storage/ipc/shmem.c | 72 +++++++++++++++-------
.../modules/test_shmem/t/001_late_shmem_alloc.pl | 28 +++++++++
src/test/modules/test_shmem/test_shmem.c | 28 ++++++++-
3 files changed, 104 insertions(+), 24 deletions(-)
