simpleperf/event_attr.cpp - platform/system/extras - Git at Google

 /*
  * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include "event_attr.h"

 #include <inttypes.h>
 #include <stdio.h>
 #include <string>
 #include <unordered_map>

 #include <android-base/logging.h>

 #include "event_type.h"
 #include "utils.h"

 static std::string BitsToString(const std::string& name, uint64_t bits,
                                 const std::vector<std::pair<int, std::string>>& bit_names) {
   std::string result;
   for (auto& p : bit_names) {
     if (bits & p.first) {
       bits &= ~p.first;
       if (!result.empty()) {
         result += ", ";
       }
       result += p.second;
     }
   }
   if (bits != 0) {
     LOG(DEBUG) << "unknown " << name << " bits: " << std::hex << bits;
   }
   return result;
 }

 static std::string SampleTypeToString(uint64_t sample_type) {
   static std::vector<std::pair<int, std::string>> sample_type_names = {
       {PERF_SAMPLE_ADDR, "addr"},
       {PERF_SAMPLE_BRANCH_STACK, "branch_stack"},
       {PERF_SAMPLE_CALLCHAIN, "callchain"},
       {PERF_SAMPLE_CPU, "cpu"},
       {PERF_SAMPLE_ID, "id"},
       {PERF_SAMPLE_IP, "ip"},
       {PERF_SAMPLE_PERIOD, "period"},
       {PERF_SAMPLE_RAW, "raw"},
       {PERF_SAMPLE_READ, "read"},
       {PERF_SAMPLE_REGS_USER, "regs_user"},
       {PERF_SAMPLE_STACK_USER, "stack_user"},
       {PERF_SAMPLE_STREAM_ID, "stream_id"},
       {PERF_SAMPLE_TID, "tid"},
       {PERF_SAMPLE_TIME, "time"},
   };
   return BitsToString("sample_type", sample_type, sample_type_names);
 }

 static std::string ReadFormatToString(uint64_t read_format) {
   static std::vector<std::pair<int, std::string>> read_format_names = {
       {PERF_FORMAT_TOTAL_TIME_ENABLED, "total_time_enabled"},
       {PERF_FORMAT_TOTAL_TIME_RUNNING, "total_time_running"},
       {PERF_FORMAT_ID, "id"},
       {PERF_FORMAT_GROUP, "group"},
   };
   return BitsToString("read_format", read_format, read_format_names);
 }

 perf_event_attr CreateDefaultPerfEventAttr(const EventType& event_type) {
   perf_event_attr attr;
   memset(&attr, 0, sizeof(attr));
   attr.size = sizeof(perf_event_attr);
   attr.type = event_type.type;
   attr.config = event_type.config;
   attr.mmap = 1;
   attr.comm = 1;
   attr.disabled = 0;
   // Changing read_format affects the layout of the data read from perf_event_file, namely
   // PerfCounter in event_fd.h.
   attr.read_format =
       PERF_FORMAT_TOTAL_TIME_ENABLED | PERF_FORMAT_TOTAL_TIME_RUNNING | PERF_FORMAT_ID;
   attr.sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID | PERF_SAMPLE_TIME | PERF_SAMPLE_PERIOD |
       PERF_SAMPLE_CPU | PERF_SAMPLE_ID;

   if (attr.type == PERF_TYPE_TRACEPOINT) {
     attr.sample_freq = 0;
     attr.sample_period = 1;
     // Tracepoint information are stored in raw data in sample records.
     attr.sample_type |= PERF_SAMPLE_RAW;
   }
   return attr;
 }

 void DumpPerfEventAttr(const perf_event_attr& attr, size_t indent) {
   std::string event_name = "unknown";
   const EventType* event_type = FindEventTypeByConfig(attr.type, attr.config);
   if (event_type != nullptr) {
     event_name = event_type->name;
   }

   PrintIndented(indent, "event_attr: for event type %s\n", event_name.c_str());

   PrintIndented(indent + 1, "type %u, size %u, config %llu\n", attr.type, attr.size, attr.config);

   if (attr.freq != 0) {
     PrintIndented(indent + 1, "sample_freq %llu\n", attr.sample_freq);
   } else {
     PrintIndented(indent + 1, "sample_period %llu\n", attr.sample_period);
   }

   PrintIndented(indent + 1, "sample_type (0x%llx) %s\n", attr.sample_type,
                 SampleTypeToString(attr.sample_type).c_str());

   PrintIndented(indent + 1, "read_format (0x%llx) %s\n", attr.read_format,
                 ReadFormatToString(attr.read_format).c_str());

   PrintIndented(indent + 1, "disabled %u, inherit %u, pinned %u, exclusive %u\n", attr.disabled,
                 attr.inherit, attr.pinned, attr.exclusive);

   PrintIndented(indent + 1, "exclude_user %u, exclude_kernel %u, exclude_hv %u\n",
                 attr.exclude_user, attr.exclude_kernel, attr.exclude_hv);

   PrintIndented(indent + 1, "exclude_idle %u, mmap %u, comm %u, freq %u\n", attr.exclude_idle,
                 attr.mmap, attr.comm, attr.freq);

   PrintIndented(indent + 1, "inherit_stat %u, enable_on_exec %u, task %u\n", attr.inherit_stat,
                 attr.enable_on_exec, attr.task);

   PrintIndented(indent + 1, "watermark %u, precise_ip %u, mmap_data %u\n", attr.watermark,
                 attr.precise_ip, attr.mmap_data);

   PrintIndented(indent + 1, "sample_id_all %u, exclude_host %u, exclude_guest %u\n",
                 attr.sample_id_all, attr.exclude_host, attr.exclude_guest);
   PrintIndented(indent + 1, "branch_sample_type 0x%" PRIx64 "\n", attr.branch_sample_type);
   PrintIndented(indent + 1, "exclude_callchain_kernel %u, exclude_callchain_user %u\n",
                 attr.exclude_callchain_kernel, attr.exclude_callchain_user);
   PrintIndented(indent + 1, "sample_regs_user 0x%" PRIx64 "\n", attr.sample_regs_user);
   PrintIndented(indent + 1, "sample_stack_user 0x%" PRIx64 "\n", attr.sample_stack_user);
 }

 bool GetCommonEventIdPositionsForAttrs(std::vector<perf_event_attr>& attrs,
                                            size_t* event_id_pos_in_sample_records,
                                            size_t* event_id_reverse_pos_in_non_sample_records) {
   // When there are more than one perf_event_attrs, we need to read event id
   // in each record to decide current record should use which attr. So
   // we need to determine the event id position in a record here.
   std::vector<uint64_t> sample_types;
   for (const auto& attr : attrs) {
     sample_types.push_back(attr.sample_type);
   }
   // First determine event_id_pos_in_sample_records.
   // If PERF_SAMPLE_IDENTIFIER is enabled, it is just after perf_event_header.
   // If PERF_SAMPLE_ID is enabled, then PERF_SAMPLE_IDENTIFIER | IP | TID | TIME | ADDR
   // should also be the same.
   bool identifier_enabled = true;
   bool id_enabled = true;
   uint64_t flags_before_id_mask = PERF_SAMPLE_IDENTIFIER | PERF_SAMPLE_IP | PERF_SAMPLE_TID |
       PERF_SAMPLE_TIME | PERF_SAMPLE_ADDR;
   uint64_t flags_before_id = sample_types[0] & flags_before_id_mask;
   bool flags_before_id_are_the_same = true;
   for (auto type : sample_types) {
     identifier_enabled &= (type & PERF_SAMPLE_IDENTIFIER) != 0;
     id_enabled &= (type & PERF_SAMPLE_ID) != 0;
     flags_before_id_are_the_same &= (type & flags_before_id_mask) == flags_before_id;
   }
   if (identifier_enabled) {
     *event_id_pos_in_sample_records = sizeof(perf_event_header);
   } else if (id_enabled && flags_before_id_are_the_same) {
     uint64_t pos = sizeof(perf_event_header);
     while (flags_before_id != 0) {
       // Each flags takes 8 bytes in sample records.
       flags_before_id &= flags_before_id - 1;
       pos += 8;
     }
     *event_id_pos_in_sample_records = pos;
   } else {
     LOG(ERROR) << "perf_event_attrs don't have a common event id position in sample records";
     return false;
   }

   // Secondly determine event_id_reverse_pos_in_non_sample_record.
   // If sample_id_all is not enabled, there is no event id in non sample records.
   // If PERF_SAMPLE_IDENTIFIER is enabled, it is at the last 8 bytes of the record.
   // If PERF_SAMPLE_ID is enabled, then PERF_SAMPLE_IDENTIFIER | CPU | STREAM_ID should
   // also be the same.
   bool sample_id_all_enabled = true;
   for (const auto& attr : attrs) {
     if (attr.sample_id_all == 0) {
       sample_id_all_enabled = false;
     }
   }
   if (!sample_id_all_enabled) {
     LOG(ERROR) << "there are perf_event_attrs not enabling sample_id_all, so can't determine "
                << "perf_event_attr for non sample records";
     return false;
   }
   uint64_t flags_after_id_mask = PERF_SAMPLE_IDENTIFIER | PERF_SAMPLE_CPU | PERF_SAMPLE_STREAM_ID;
   uint64_t flags_after_id = sample_types[0] & flags_after_id_mask;
   bool flags_after_id_are_the_same = true;
   for (auto type : sample_types) {
     flags_after_id_are_the_same &= (type & flags_after_id_mask) == flags_after_id;
   }
   if (identifier_enabled) {
     *event_id_reverse_pos_in_non_sample_records = 8;
   } else if (id_enabled && flags_after_id_are_the_same) {
     uint64_t pos = 8;
     while (flags_after_id != 0) {
       // Each flag takes 8 bytes in sample_id of non sample records.
       flags_after_id &= flags_after_id - 1;
       pos += 8;
     }
     *event_id_reverse_pos_in_non_sample_records = pos;
   } else {
     LOG(ERROR) << "perf_event_attrs don't have a common event id reverse position in non sample records";
     return false;
   }
   return true;
 }

 bool IsTimestampSupported(const perf_event_attr& attr) {
   return attr.sample_id_all && (attr.sample_type & PERF_SAMPLE_TIME);
 }
	/*
	* Copyright (C) 2015 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "event_attr.h"

	#include <inttypes.h>
	#include <stdio.h>
	#include <string>
	#include <unordered_map>

	#include <android-base/logging.h>

	#include "event_type.h"
	#include "utils.h"

	static std::string BitsToString(const std::string& name, uint64_t bits,
	const std::vector<std::pair<int, std::string>>& bit_names) {
	std::string result;
	for (auto& p : bit_names) {
	if (bits & p.first) {
	bits &= ~p.first;
	if (!result.empty()) {
	result += ", ";
	}
	result += p.second;
	}
	}
	if (bits != 0) {
	LOG(DEBUG) << "unknown " << name << " bits: " << std::hex << bits;
	}
	return result;
	}

	static std::string SampleTypeToString(uint64_t sample_type) {
	static std::vector<std::pair<int, std::string>> sample_type_names = {
	{PERF_SAMPLE_ADDR, "addr"},
	{PERF_SAMPLE_BRANCH_STACK, "branch_stack"},
	{PERF_SAMPLE_CALLCHAIN, "callchain"},
	{PERF_SAMPLE_CPU, "cpu"},
	{PERF_SAMPLE_ID, "id"},
	{PERF_SAMPLE_IP, "ip"},
	{PERF_SAMPLE_PERIOD, "period"},
	{PERF_SAMPLE_RAW, "raw"},
	{PERF_SAMPLE_READ, "read"},
	{PERF_SAMPLE_REGS_USER, "regs_user"},
	{PERF_SAMPLE_STACK_USER, "stack_user"},
	{PERF_SAMPLE_STREAM_ID, "stream_id"},
	{PERF_SAMPLE_TID, "tid"},
	{PERF_SAMPLE_TIME, "time"},
	};
	return BitsToString("sample_type", sample_type, sample_type_names);
	}

	static std::string ReadFormatToString(uint64_t read_format) {
	static std::vector<std::pair<int, std::string>> read_format_names = {
	{PERF_FORMAT_TOTAL_TIME_ENABLED, "total_time_enabled"},
	{PERF_FORMAT_TOTAL_TIME_RUNNING, "total_time_running"},
	{PERF_FORMAT_ID, "id"},
	{PERF_FORMAT_GROUP, "group"},
	};
	return BitsToString("read_format", read_format, read_format_names);
	}

	perf_event_attr CreateDefaultPerfEventAttr(const EventType& event_type) {
	perf_event_attr attr;
	memset(&attr, 0, sizeof(attr));
	attr.size = sizeof(perf_event_attr);
	attr.type = event_type.type;
	attr.config = event_type.config;
	attr.mmap = 1;
	attr.comm = 1;
	attr.disabled = 0;
	// Changing read_format affects the layout of the data read from perf_event_file, namely
	// PerfCounter in event_fd.h.
	attr.read_format =
	PERF_FORMAT_TOTAL_TIME_ENABLED \| PERF_FORMAT_TOTAL_TIME_RUNNING \| PERF_FORMAT_ID;
	attr.sample_type \|= PERF_SAMPLE_IP \| PERF_SAMPLE_TID \| PERF_SAMPLE_TIME \| PERF_SAMPLE_PERIOD \|
	PERF_SAMPLE_CPU \| PERF_SAMPLE_ID;

	if (attr.type == PERF_TYPE_TRACEPOINT) {
	attr.sample_freq = 0;
	attr.sample_period = 1;
	// Tracepoint information are stored in raw data in sample records.
	attr.sample_type \|= PERF_SAMPLE_RAW;
	}
	return attr;
	}

	void DumpPerfEventAttr(const perf_event_attr& attr, size_t indent) {
	std::string event_name = "unknown";
	const EventType* event_type = FindEventTypeByConfig(attr.type, attr.config);
	if (event_type != nullptr) {
	event_name = event_type->name;
	}

	PrintIndented(indent, "event_attr: for event type %s\n", event_name.c_str());

	PrintIndented(indent + 1, "type %u, size %u, config %llu\n", attr.type, attr.size, attr.config);

	if (attr.freq != 0) {
	PrintIndented(indent + 1, "sample_freq %llu\n", attr.sample_freq);
	} else {
	PrintIndented(indent + 1, "sample_period %llu\n", attr.sample_period);
	}

	PrintIndented(indent + 1, "sample_type (0x%llx) %s\n", attr.sample_type,
	SampleTypeToString(attr.sample_type).c_str());

	PrintIndented(indent + 1, "read_format (0x%llx) %s\n", attr.read_format,
	ReadFormatToString(attr.read_format).c_str());

	PrintIndented(indent + 1, "disabled %u, inherit %u, pinned %u, exclusive %u\n", attr.disabled,
	attr.inherit, attr.pinned, attr.exclusive);

	PrintIndented(indent + 1, "exclude_user %u, exclude_kernel %u, exclude_hv %u\n",
	attr.exclude_user, attr.exclude_kernel, attr.exclude_hv);

	PrintIndented(indent + 1, "exclude_idle %u, mmap %u, comm %u, freq %u\n", attr.exclude_idle,
	attr.mmap, attr.comm, attr.freq);

	PrintIndented(indent + 1, "inherit_stat %u, enable_on_exec %u, task %u\n", attr.inherit_stat,
	attr.enable_on_exec, attr.task);

	PrintIndented(indent + 1, "watermark %u, precise_ip %u, mmap_data %u\n", attr.watermark,
	attr.precise_ip, attr.mmap_data);

	PrintIndented(indent + 1, "sample_id_all %u, exclude_host %u, exclude_guest %u\n",
	attr.sample_id_all, attr.exclude_host, attr.exclude_guest);
	PrintIndented(indent + 1, "branch_sample_type 0x%" PRIx64 "\n", attr.branch_sample_type);
	PrintIndented(indent + 1, "exclude_callchain_kernel %u, exclude_callchain_user %u\n",
	attr.exclude_callchain_kernel, attr.exclude_callchain_user);
	PrintIndented(indent + 1, "sample_regs_user 0x%" PRIx64 "\n", attr.sample_regs_user);
	PrintIndented(indent + 1, "sample_stack_user 0x%" PRIx64 "\n", attr.sample_stack_user);
	}

	bool GetCommonEventIdPositionsForAttrs(std::vector<perf_event_attr>& attrs,
	size_t* event_id_pos_in_sample_records,
	size_t* event_id_reverse_pos_in_non_sample_records) {
	// When there are more than one perf_event_attrs, we need to read event id
	// in each record to decide current record should use which attr. So
	// we need to determine the event id position in a record here.
	std::vector<uint64_t> sample_types;
	for (const auto& attr : attrs) {
	sample_types.push_back(attr.sample_type);
	}
	// First determine event_id_pos_in_sample_records.
	// If PERF_SAMPLE_IDENTIFIER is enabled, it is just after perf_event_header.
	// If PERF_SAMPLE_ID is enabled, then PERF_SAMPLE_IDENTIFIER \| IP \| TID \| TIME \| ADDR
	// should also be the same.
	bool identifier_enabled = true;
	bool id_enabled = true;
	uint64_t flags_before_id_mask = PERF_SAMPLE_IDENTIFIER \| PERF_SAMPLE_IP \| PERF_SAMPLE_TID \|
	PERF_SAMPLE_TIME \| PERF_SAMPLE_ADDR;
	uint64_t flags_before_id = sample_types[0] & flags_before_id_mask;
	bool flags_before_id_are_the_same = true;
	for (auto type : sample_types) {
	identifier_enabled &= (type & PERF_SAMPLE_IDENTIFIER) != 0;
	id_enabled &= (type & PERF_SAMPLE_ID) != 0;
	flags_before_id_are_the_same &= (type & flags_before_id_mask) == flags_before_id;
	}
	if (identifier_enabled) {
	*event_id_pos_in_sample_records = sizeof(perf_event_header);
	} else if (id_enabled && flags_before_id_are_the_same) {
	uint64_t pos = sizeof(perf_event_header);
	while (flags_before_id != 0) {
	// Each flags takes 8 bytes in sample records.
	flags_before_id &= flags_before_id - 1;
	pos += 8;
	}
	*event_id_pos_in_sample_records = pos;
	} else {
	LOG(ERROR) << "perf_event_attrs don't have a common event id position in sample records";
	return false;
	}

	// Secondly determine event_id_reverse_pos_in_non_sample_record.
	// If sample_id_all is not enabled, there is no event id in non sample records.
	// If PERF_SAMPLE_IDENTIFIER is enabled, it is at the last 8 bytes of the record.
	// If PERF_SAMPLE_ID is enabled, then PERF_SAMPLE_IDENTIFIER \| CPU \| STREAM_ID should
	// also be the same.
	bool sample_id_all_enabled = true;
	for (const auto& attr : attrs) {
	if (attr.sample_id_all == 0) {
	sample_id_all_enabled = false;
	}
	}
	if (!sample_id_all_enabled) {
	LOG(ERROR) << "there are perf_event_attrs not enabling sample_id_all, so can't determine "
	<< "perf_event_attr for non sample records";
	return false;
	}
	uint64_t flags_after_id_mask = PERF_SAMPLE_IDENTIFIER \| PERF_SAMPLE_CPU \| PERF_SAMPLE_STREAM_ID;
	uint64_t flags_after_id = sample_types[0] & flags_after_id_mask;
	bool flags_after_id_are_the_same = true;
	for (auto type : sample_types) {
	flags_after_id_are_the_same &= (type & flags_after_id_mask) == flags_after_id;
	}
	if (identifier_enabled) {
	*event_id_reverse_pos_in_non_sample_records = 8;
	} else if (id_enabled && flags_after_id_are_the_same) {
	uint64_t pos = 8;
	while (flags_after_id != 0) {
	// Each flag takes 8 bytes in sample_id of non sample records.
	flags_after_id &= flags_after_id - 1;
	pos += 8;
	}
	*event_id_reverse_pos_in_non_sample_records = pos;
	} else {
	LOG(ERROR) << "perf_event_attrs don't have a common event id reverse position in non sample records";
	return false;
	}
	return true;
	}

	bool IsTimestampSupported(const perf_event_attr& attr) {
	return attr.sample_id_all && (attr.sample_type & PERF_SAMPLE_TIME);
	}