[tracing] Introduce config to setup memory-infra peak detection

base/trace_event/memory_dump_request_args.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_TRACE_EVENT_MEMORY_DUMP_REQUEST_ARGS_H_
 #define BASE_TRACE_EVENT_MEMORY_DUMP_REQUEST_ARGS_H_
 
 // This file defines the types and structs used to issue memory dump requests.
 // These are also used in the IPCs for coordinating inter-process memory dumps.
 
 #include <stdint.h>
 #include <string>
 
 #include "base/base_export.h"
 #include "base/callback.h"
 
 namespace base {
 namespace trace_event {
 
 // Captures the reason why a memory dump is being requested. This is to allow
 // selective enabling of dumps, filtering and post-processing.
 enum class MemoryDumpType {
   TASK_BEGIN,         // Dumping memory at the beginning of a message-loop task.

[Primiano Tucci (use gerrit), 2016/12/15 15:40:43]

since you are touching this, can you plz remove TASK_BEGIN/END. We ended up
never using them (imagine triggering a dump on each task, LOL) and I always
forgot to remove them.
Don't worry about numeric values of the enum changing (i.e. PERIODIC now being
0). We use the strings in trace-viewer and nothing should rely on the real int
value of this.

[ssid, 2016/12/15 19:48:06]

Done.

   TASK_END,           // Dumping memory at the ending of a message-loop task.
   PERIODIC_INTERVAL,  // Dumping memory at periodic intervals.
   EXPLICITLY_TRIGGERED,  // Non maskable dump request.
-  LAST = EXPLICITLY_TRIGGERED // For IPC macros.
+  PEAK_MEMORY_USAGE,     // Dumping memory at detected peak total memory usage.
+  LAST = PEAK_MEMORY_USAGE  // For IPC macros.
 };
 
 // Tells the MemoryDumpProvider(s) how much detailed their dumps should be.
 enum class MemoryDumpLevelOfDetail : uint32_t {
   FIRST,
 
   // For background tracing mode. The dump time is quick, and typically just the
   // totals are expected. Suballocations need not be specified. Dump name must
   // contain only pre-defined strings and string arguments cannot be added.
   BACKGROUND = FIRST,
@@ skipping 27 matching lines @@
 // providers. Dump providers are expected to read the args for creating dumps.
 struct MemoryDumpArgs {
   // Specifies how detailed the dumps should be.
   MemoryDumpLevelOfDetail level_of_detail;
 };
 
 using MemoryDumpCallback = Callback<void(uint64_t dump_guid, bool success)>;
 
 BASE_EXPORT const char* MemoryDumpTypeToString(const MemoryDumpType& dump_type);
 
+BASE_EXPORT MemoryDumpType StringToMemoryDumpType(const std::string& str);
+
 BASE_EXPORT const char* MemoryDumpLevelOfDetailToString(
     const MemoryDumpLevelOfDetail& level_of_detail);
 
 BASE_EXPORT MemoryDumpLevelOfDetail
 StringToMemoryDumpLevelOfDetail(const std::string& str);
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_MEMORY_DUMP_REQUEST_ARGS_H_