On Sat, Nov 22, 2025 at 01:41:21PM -0600, Nathan Bossart wrote: > I'll give what you suggested a try. It seems reasonable enough.
Here is a mostly-untested first try. -- nathan
>From e639d70a10f6288034ebe433a22b9dbc53562b01 Mon Sep 17 00:00:00 2001 From: Nathan Bossart <[email protected]> Date: Mon, 24 Nov 2025 11:03:52 -0600 Subject: [PATCH v1 1/2] Revert "Teach DSM registry to ERROR if attaching to an uninitialized entry." This reverts commit 1165a933aab1355757a43cfd9193b6cce06f573b. --- src/backend/storage/ipc/dsm_registry.c | 34 +++----------------------- 1 file changed, 4 insertions(+), 30 deletions(-) diff --git a/src/backend/storage/ipc/dsm_registry.c b/src/backend/storage/ipc/dsm_registry.c index 7eba8a8cffb..a926b9c3f32 100644 --- a/src/backend/storage/ipc/dsm_registry.c +++ b/src/backend/storage/ipc/dsm_registry.c @@ -93,7 +93,6 @@ typedef struct DSMRegistryEntry { char name[NAMEDATALEN]; DSMREntryType type; - bool initialized; union { NamedDSMState dsm; @@ -217,7 +216,6 @@ GetNamedDSMSegment(const char *name, size_t size, dsm_segment *seg; entry->type = DSMR_ENTRY_TYPE_DSM; - entry->initialized = false; /* Initialize the segment. */ seg = dsm_create(size, 0); @@ -230,21 +228,13 @@ GetNamedDSMSegment(const char *name, size_t size, if (init_callback) (*init_callback) (ret); - - entry->initialized = true; } else if (entry->type != DSMR_ENTRY_TYPE_DSM) ereport(ERROR, - (errmsg("requested DSM segment \"%s\" does not match type of existing entry", - name))); - else if (!entry->initialized) - ereport(ERROR, - (errmsg("requested DSM segment \"%s\" failed initialization", - name))); + (errmsg("requested DSM segment does not match type of existing entry"))); else if (entry->dsm.size != size) ereport(ERROR, - (errmsg("requested DSM segment \"%s\" does not match size of existing entry", - name))); + (errmsg("requested DSM segment size does not match size of existing segment"))); else { NamedDSMState *state = &entry->dsm; @@ -307,7 +297,6 @@ GetNamedDSA(const char *name, bool *found) NamedDSAState *state = &entry->dsa; entry->type = DSMR_ENTRY_TYPE_DSA; - entry->initialized = false; /* Initialize the LWLock tranche for the DSA. */ state->tranche = LWLockNewTrancheId(name); @@ -319,17 +308,10 @@ GetNamedDSA(const char *name, bool *found) /* Store handle for other backends to use. */ state->handle = dsa_get_handle(ret); - - entry->initialized = true; } else if (entry->type != DSMR_ENTRY_TYPE_DSA) ereport(ERROR, - (errmsg("requested DSA \"%s\" does not match type of existing entry", - name))); - else if (!entry->initialized) - ereport(ERROR, - (errmsg("requested DSA \"%s\" failed initialization", - name))); + (errmsg("requested DSA does not match type of existing entry"))); else { NamedDSAState *state = &entry->dsa; @@ -390,7 +372,6 @@ GetNamedDSHash(const char *name, const dshash_parameters *params, bool *found) dsa_area *dsa; entry->type = DSMR_ENTRY_TYPE_DSH; - entry->initialized = false; /* Initialize the LWLock tranche for the hash table. */ dsh_state->tranche = LWLockNewTrancheId(name); @@ -408,17 +389,10 @@ GetNamedDSHash(const char *name, const dshash_parameters *params, bool *found) /* Store handles for other backends to use. */ dsh_state->dsa_handle = dsa_get_handle(dsa); dsh_state->dsh_handle = dshash_get_hash_table_handle(ret); - - entry->initialized = true; } else if (entry->type != DSMR_ENTRY_TYPE_DSH) ereport(ERROR, - (errmsg("requested DSHash \"%s\" does not match type of existing entry", - name))); - else if (!entry->initialized) - ereport(ERROR, - (errmsg("requested DSHash \"%s\" failed initialization", - name))); + (errmsg("requested DSHash does not match type of existing entry"))); else { NamedDSHState *dsh_state = &entry->dsh; -- 2.39.5 (Apple Git-154)
>From 6da47303c5e5acaca4cc9808316a0457f6c6f0af Mon Sep 17 00:00:00 2001 From: Nathan Bossart <[email protected]> Date: Mon, 24 Nov 2025 12:28:23 -0600 Subject: [PATCH v1 2/2] handle ERRORs in DSM registry functions --- src/backend/storage/ipc/dsm_registry.c | 129 ++++++++++++++++++++++--- 1 file changed, 115 insertions(+), 14 deletions(-) diff --git a/src/backend/storage/ipc/dsm_registry.c b/src/backend/storage/ipc/dsm_registry.c index a926b9c3f32..7d1b584d166 100644 --- a/src/backend/storage/ipc/dsm_registry.c +++ b/src/backend/storage/ipc/dsm_registry.c @@ -154,10 +154,24 @@ init_dsm_registry(void) if (DSMRegistryCtx->dshh == DSHASH_HANDLE_INVALID) { /* Initialize dynamic shared hash table for registry. */ - dsm_registry_dsa = dsa_create(LWTRANCHE_DSM_REGISTRY_DSA); + PG_TRY(); + { + dsm_registry_dsa = dsa_create(LWTRANCHE_DSM_REGISTRY_DSA); + dsm_registry_table = dshash_create(dsm_registry_dsa, &dsh_params, NULL); + } + PG_CATCH(); + { + if (dsm_registry_dsa) + { + dsa_detach(dsm_registry_dsa); + dsm_registry_dsa = NULL; + } + PG_RE_THROW(); + } + PG_END_TRY(); + dsa_pin(dsm_registry_dsa); dsa_pin_mapping(dsm_registry_dsa); - dsm_registry_table = dshash_create(dsm_registry_dsa, &dsh_params, NULL); /* Store handles in shared memory for other backends to use. */ DSMRegistryCtx->dsah = dsa_get_handle(dsm_registry_dsa); @@ -216,18 +230,38 @@ GetNamedDSMSegment(const char *name, size_t size, dsm_segment *seg; entry->type = DSMR_ENTRY_TYPE_DSM; + state->handle = DSM_HANDLE_INVALID; /* Initialize the segment. */ - seg = dsm_create(size, 0); + PG_TRY(); + { + seg = dsm_create(size, 0); + } + PG_CATCH(); + { + dshash_delete_entry(dsm_registry_table, entry); + PG_RE_THROW(); + } + PG_END_TRY(); + + PG_TRY(); + { + ret = dsm_segment_address(seg); + if (init_callback) + (*init_callback) (ret); + } + PG_CATCH(); + { + dsm_detach(seg); + dshash_delete_entry(dsm_registry_table, entry); + PG_RE_THROW(); + } + PG_END_TRY(); dsm_pin_segment(seg); dsm_pin_mapping(seg); state->handle = dsm_segment_handle(seg); state->size = size; - ret = dsm_segment_address(seg); - - if (init_callback) - (*init_callback) (ret); } else if (entry->type != DSMR_ENTRY_TYPE_DSM) ereport(ERROR, @@ -297,9 +331,19 @@ GetNamedDSA(const char *name, bool *found) NamedDSAState *state = &entry->dsa; entry->type = DSMR_ENTRY_TYPE_DSA; + state->handle = DSA_HANDLE_INVALID; /* Initialize the LWLock tranche for the DSA. */ - state->tranche = LWLockNewTrancheId(name); + PG_TRY(); + { + state->tranche = LWLockNewTrancheId(name); + } + PG_CATCH(); + { + dshash_delete_entry(dsm_registry_table, entry); + PG_RE_THROW(); + } + PG_END_TRY(); /* Initialize the DSA. */ ret = dsa_create(state->tranche); @@ -312,6 +356,16 @@ GetNamedDSA(const char *name, bool *found) else if (entry->type != DSMR_ENTRY_TYPE_DSA) ereport(ERROR, (errmsg("requested DSA does not match type of existing entry"))); + else if (entry->dsa.handle == DSA_HANDLE_INVALID) + { + NamedDSAState *state = &entry->dsa; + + ret = dsa_create(state->tranche); + + dsa_pin(ret); + dsa_pin_mapping(ret); + state->handle = dsa_get_handle(ret); + } else { NamedDSAState *state = &entry->dsa; @@ -372,19 +426,40 @@ GetNamedDSHash(const char *name, const dshash_parameters *params, bool *found) dsa_area *dsa; entry->type = DSMR_ENTRY_TYPE_DSH; + dsh_state->dsa_handle = DSA_HANDLE_INVALID; + dsh_state->dsh_handle = DSHASH_HANDLE_INVALID; /* Initialize the LWLock tranche for the hash table. */ - dsh_state->tranche = LWLockNewTrancheId(name); + PG_TRY(); + { + dsh_state->tranche = LWLockNewTrancheId(name); + } + PG_CATCH(); + { + dshash_delete_entry(dsm_registry_table, entry); + PG_RE_THROW(); + } + PG_END_TRY(); /* Initialize the DSA for the hash table. */ dsa = dsa_create(dsh_state->tranche); - dsa_pin(dsa); - dsa_pin_mapping(dsa); /* Initialize the dshash table. */ - memcpy(¶ms_copy, params, sizeof(dshash_parameters)); - params_copy.tranche_id = dsh_state->tranche; - ret = dshash_create(dsa, ¶ms_copy, NULL); + PG_TRY(); + { + memcpy(¶ms_copy, params, sizeof(dshash_parameters)); + params_copy.tranche_id = dsh_state->tranche; + ret = dshash_create(dsa, ¶ms_copy, NULL); + } + PG_CATCH(); + { + dsa_detach(dsa); + PG_RE_THROW(); + } + PG_END_TRY(); + + dsa_pin(dsa); + dsa_pin_mapping(dsa); /* Store handles for other backends to use. */ dsh_state->dsa_handle = dsa_get_handle(dsa); @@ -393,6 +468,32 @@ GetNamedDSHash(const char *name, const dshash_parameters *params, bool *found) else if (entry->type != DSMR_ENTRY_TYPE_DSH) ereport(ERROR, (errmsg("requested DSHash does not match type of existing entry"))); + else if (entry->dsh.dsa_handle == DSA_HANDLE_INVALID) + { + NamedDSHState *dsh_state = &entry->dsh; + dshash_parameters params_copy; + dsa_area *dsa; + + dsa = dsa_create(dsh_state->tranche); + + PG_TRY(); + { + memcpy(¶ms_copy, params, sizeof(dshash_parameters)); + params_copy.tranche_id = dsh_state->tranche; + ret = dshash_create(dsa, ¶ms_copy, NULL); + } + PG_CATCH(); + { + dsa_detach(dsa); + PG_RE_THROW(); + } + PG_END_TRY(); + + dsa_pin(dsa); + dsa_pin_mapping(dsa); + dsh_state->dsa_handle = dsa_get_handle(dsa); + dsh_state->dsh_handle = dshash_get_hash_table_handle(ret); + } else { NamedDSHState *dsh_state = &entry->dsh; -- 2.39.5 (Apple Git-154)
