Prevents the cloning of rows with outgoing or incoming weak references when those rows aren't being modified.
It improves the OVSDB Server performance when many rows with weak references are involved in a transaction. Signed-off-by: Esteban Rodriguez Betancourt <[email protected]> --- include/openvswitch/list.h | 19 +++++++++++++++++ ovsdb/row.h | 8 ++++--- ovsdb/transaction.c | 52 +++++++++++++++++++++++++++++++++++++++++----- tests/library.at | 2 +- tests/test-list.c | 41 ++++++++++++++++++++++++++++++++++++ 5 files changed, 113 insertions(+), 9 deletions(-) diff --git a/include/openvswitch/list.h b/include/openvswitch/list.h index 5c2cca4..a762ef7 100644 --- a/include/openvswitch/list.h +++ b/include/openvswitch/list.h @@ -288,4 +288,23 @@ ovs_list_is_short(const struct ovs_list *list) return list->next == list->prev; } +/* Transplant a list into another, and resets the origin list */ +static inline void +ovs_list_transplant(const struct ovs_list *dst_, const struct ovs_list *src_) +{ + struct ovs_list *src, *dst; + src = CONST_CAST(struct ovs_list *, src_); + dst = CONST_CAST(struct ovs_list *, dst_); + + /* Chain last element of dst with first of src */ + src->next->prev = dst->prev; + dst->prev->next = src->next; + + /* Chain last element of src with head of dst */ + src->prev->next = dst; + dst->prev = src->prev; + + ovs_list_init(src); +} + #endif /* list.h */ diff --git a/ovsdb/row.h b/ovsdb/row.h index b1d1edd..b38c7dd 100644 --- a/ovsdb/row.h +++ b/ovsdb/row.h @@ -36,9 +36,11 @@ struct ovsdb_column_set; * ovsdb_weak_ref" structures are created for them. */ struct ovsdb_weak_ref { - struct ovs_list src_node; /* In src->src_refs list. */ - struct ovs_list dst_node; /* In destination row's dst_refs list. */ - struct ovsdb_row *src; /* Source row. */ + struct ovs_list src_node; /* In src->src_refs list. */ + struct ovs_list dst_node; /* In destination row's dst_refs list. */ + struct ovsdb_row *src; /* Source row. */ + struct ovsdb_table *dst_table; /* Destination table. */ + struct uuid dst; /* Destination row uuid. */ }; /* A row in a database table. */ diff --git a/ovsdb/transaction.c b/ovsdb/transaction.c index 9e12a62..5ad3de0 100644 --- a/ovsdb/transaction.c +++ b/ovsdb/transaction.c @@ -436,8 +436,48 @@ ovsdb_txn_row_commit(struct ovsdb_txn *txn OVS_UNUSED, return NULL; } +static struct ovsdb_error * +ovsdb_txn_update_weak_refs(struct ovsdb_txn *txn OVS_UNUSED, + struct ovsdb_txn_row *txn_row) +{ + struct ovsdb_weak_ref *weak, *next; + + /* Remove the weak references originating in the old version of the row */ + if (txn_row->old) { + LIST_FOR_EACH_SAFE (weak, next, src_node, &txn_row->old->src_refs) { + ovs_list_remove(&weak->src_node); + ovs_list_remove(&weak->dst_node); + free(weak); + } + } + + /* Although the originating rows have the responsability of updating the + * weak references in the dst, is possible that some source rows aren't + * part of the transaction. + * In that situation this row needs to move the list of incoming weak + * references from the old row into the new one. + */ + if (txn_row->old && txn_row->new) { + /* Move the incoming weak references from old to new */ + ovs_list_transplant(&txn_row->new->dst_refs, &txn_row->old->dst_refs); + } + + /* Insert the weak references originating in the new version of the row */ + struct ovsdb_row *dst_row; + if (txn_row->new) { + LIST_FOR_EACH_SAFE (weak, next, src_node, &txn_row->new->src_refs) { + /* dst_row MUST exist */ + dst_row = CONST_CAST(struct ovsdb_row *, + ovsdb_table_get_row(weak->dst_table, &weak->dst)); + ovs_list_insert(&dst_row->dst_refs, &weak->dst_node); + } + } + + return NULL; +} + static void -add_weak_ref(struct ovsdb_txn *txn, +add_weak_ref(struct ovsdb_txn *txn OVS_UNUSED, const struct ovsdb_row *src_, const struct ovsdb_row *dst_) { struct ovsdb_row *src = CONST_CAST(struct ovsdb_row *, src_); @@ -448,8 +488,6 @@ add_weak_ref(struct ovsdb_txn *txn, return; } - dst = ovsdb_txn_row_modify(txn, dst); - if (!ovs_list_is_empty(&dst->dst_refs)) { /* Omit duplicates. */ weak = CONTAINER_OF(ovs_list_back(&dst->dst_refs), @@ -461,7 +499,10 @@ add_weak_ref(struct ovsdb_txn *txn, weak = xmalloc(sizeof *weak); weak->src = src; - ovs_list_push_back(&dst->dst_refs, &weak->dst_node); + weak->dst_table = dst->table; + memcpy(&weak->dst, ovsdb_row_get_uuid(dst), sizeof(struct uuid)); + /* The dst_refs list is updated at commit time */ + ovs_list_init(&weak->dst_node); ovs_list_push_back(&src->src_refs, &weak->src_node); } @@ -471,7 +512,7 @@ assess_weak_refs(struct ovsdb_txn *txn, struct ovsdb_txn_row *txn_row) struct ovsdb_table *table; struct shash_node *node; - if (txn_row->old) { + if (txn_row->old && !txn_row->new) { /* Mark rows that have weak references to 'txn_row' as modified, so * that their weak references will get reassessed. */ struct ovsdb_weak_ref *weak, *next; @@ -838,6 +879,7 @@ ovsdb_txn_commit_(struct ovsdb_txn *txn, bool durable) /* Finalize commit. */ txn->db->run_triggers = true; + ovsdb_error_assert(for_each_txn_row(txn, ovsdb_txn_update_weak_refs)); ovsdb_error_assert(for_each_txn_row(txn, ovsdb_txn_row_commit)); ovsdb_txn_free(txn); diff --git a/tests/library.at b/tests/library.at index e5095a0..69a14e9 100644 --- a/tests/library.at +++ b/tests/library.at @@ -44,7 +44,7 @@ AT_CHECK([ovstest test-atomic]) AT_CLEANUP AT_SETUP([linked lists]) -AT_CHECK([ovstest test-list], [0], [... +AT_CHECK([ovstest test-list], [0], [.... ]) AT_CLEANUP diff --git a/tests/test-list.c b/tests/test-list.c index d413f30..d85b9ad 100644 --- a/tests/test-list.c +++ b/tests/test-list.c @@ -185,6 +185,46 @@ test_list_for_each_pop(void) } } +/* Tests the transplant of one list into another */ +static void +test_list_transplant(void) +{ + struct ovs_list list_a, list_b; + struct element a, b, c, d; + + a.value = 0; + b.value = 1; + c.value = 2; + d.value = 3; + + ovs_list_init(&list_a); + ovs_list_init(&list_b); + + ovs_list_insert(&list_a, &a.node); + ovs_list_insert(&list_a, &b.node); + ovs_list_insert(&list_b, &c.node); + ovs_list_insert(&list_b, &d.node); + + /* Check test preconditions */ + assert(2 == ovs_list_size(&list_a)); + assert(2 == ovs_list_size(&list_b)); + + /* Perform transplant */ + ovs_list_transplant(&list_a, &list_b); + + /* Check expected result */ + assert(4 == ovs_list_size(&list_a)); + assert(0 == ovs_list_size(&list_b)); + + struct element *node; + int n = 0; + LIST_FOR_EACH(node, node, &list_a) { + assert(n == node->value); + n++; + } + assert(n == 4); +} + static void run_test(void (*function)(void)) { @@ -198,6 +238,7 @@ test_list_main(int argc OVS_UNUSED, char *argv[] OVS_UNUSED) run_test(test_list_construction); run_test(test_list_for_each_safe); run_test(test_list_for_each_pop); + run_test(test_list_transplant); printf("\n"); } -- 1.9.1 _______________________________________________ dev mailing list [email protected] http://openvswitch.org/mailman/listinfo/dev
