1 /*
2  * Copyright (C) 2019 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "src/trace_processor/counter_definitions_table.h"
18 
19 #include <string>
20 
21 #include "src/trace_processor/storage_columns.h"
22 
23 namespace perfetto {
24 namespace trace_processor {
25 
CounterDefinitionsTable(sqlite3 *,const TraceStorage * storage)26 CounterDefinitionsTable::CounterDefinitionsTable(sqlite3*,
27                                                  const TraceStorage* storage)
28     : storage_(storage) {}
29 
RegisterTable(sqlite3 * db,const TraceStorage * storage)30 void CounterDefinitionsTable::RegisterTable(sqlite3* db,
31                                             const TraceStorage* storage) {
32   Table::Register<CounterDefinitionsTable>(db, storage, "counter_definitions");
33 }
34 
CreateStorageSchema()35 StorageSchema CounterDefinitionsTable::CreateStorageSchema() {
36   const auto& cs = storage_->counter_definitions();
37   return StorageSchema::Builder()
38       .AddGenericNumericColumn("counter_id", RowAccessor())
39       .AddStringColumn("name", &cs.name_ids(), &storage_->string_pool())
40       .AddNumericColumn("ref", &cs.refs())
41       .AddStringColumn("ref_type", &cs.types(), &GetRefTypeStringMap())
42       .Build({"counter_id"});
43 }
44 
RowCount()45 uint32_t CounterDefinitionsTable::RowCount() {
46   return storage_->counter_definitions().size();
47 }
48 
BestIndex(const QueryConstraints & qc,BestIndexInfo * info)49 int CounterDefinitionsTable::BestIndex(const QueryConstraints& qc,
50                                        BestIndexInfo* info) {
51   info->estimated_cost = EstimateCost(qc);
52 
53   // Only the string columns are handled by SQLite
54   size_t name_index = schema().ColumnIndexFromName("name");
55   size_t ref_type_index = schema().ColumnIndexFromName("ref_type");
56   info->order_by_consumed = true;
57   for (size_t i = 0; i < qc.constraints().size(); i++) {
58     auto col = static_cast<size_t>(qc.constraints()[i].iColumn);
59     info->omit[i] = col != name_index && col != ref_type_index;
60   }
61 
62   return SQLITE_OK;
63 }
64 
EstimateCost(const QueryConstraints & qc)65 uint32_t CounterDefinitionsTable::EstimateCost(const QueryConstraints& qc) {
66   // If there is a constraint on the counter id, we can efficiently filter
67   // to a single row.
68   if (HasEqConstraint(qc, "counter_id"))
69     return 1;
70 
71   auto eq_name = HasEqConstraint(qc, "name");
72   auto eq_ref = HasEqConstraint(qc, "ref");
73   auto eq_ref_type = HasEqConstraint(qc, "ref_type");
74 
75   // If there is a constraint on all three columns, we are going to only return
76   // exaclty one row for sure so make the cost 1.
77   if (eq_name && eq_ref && eq_ref_type)
78     return 1;
79   else if (eq_name && eq_ref)
80     return 10;
81   else if (eq_name)
82     return 100;
83   return RowCount();
84 }
85 
86 }  // namespace trace_processor
87 }  // namespace perfetto
88