diff options
| -rw-r--r-- | src/backend/storage/ipc/dsm.c | 18 | ||||
| -rw-r--r-- | src/include/storage/dsm.h | 1 |
2 files changed, 19 insertions, 0 deletions
diff --git a/src/backend/storage/ipc/dsm.c b/src/backend/storage/ipc/dsm.c index 7ce45caaf9b..6ff1c7ea2aa 100644 --- a/src/backend/storage/ipc/dsm.c +++ b/src/backend/storage/ipc/dsm.c @@ -796,6 +796,24 @@ dsm_pin_mapping(dsm_segment *seg) } /* + * Arrange to remove a dynamic shared memory mapping at cleanup time. + * + * dsm_pin_mapping() can be used to preserve a mapping for the entire + * lifetime of a process; this function reverses that decision, making + * the segment owned by the current resource owner. This may be useful + * just before performing some operation that will invalidate the segment + * for future use by this backend. + */ +void +dsm_unpin_mapping(dsm_segment *seg) +{ + Assert(seg->resowner == NULL); + ResourceOwnerEnlargeDSMs(CurrentResourceOwner); + seg->resowner = CurrentResourceOwner; + ResourceOwnerRememberDSM(seg->resowner, seg); +} + +/* * Keep a dynamic shared memory segment until postmaster shutdown. * * This function should not be called more than once per segment; diff --git a/src/include/storage/dsm.h b/src/include/storage/dsm.h index a83b35fd664..cfe5d48e871 100644 --- a/src/include/storage/dsm.h +++ b/src/include/storage/dsm.h @@ -37,6 +37,7 @@ extern void dsm_detach(dsm_segment *seg); /* Resource management functions. */ extern void dsm_pin_mapping(dsm_segment *seg); +extern void dsm_unpin_mapping(dsm_segment *seg); extern void dsm_pin_segment(dsm_segment *seg); extern dsm_segment *dsm_find_mapping(dsm_handle h); |