src/profiling/memory/client.cc - platform/external/perfetto - Gitiles

 /*
  * Copyright (C) 2018 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 "src/profiling/memory/client.h"

 #include <inttypes.h>
 #include <sys/socket.h>
 #include <sys/syscall.h>
 #include <sys/un.h>
 #include <unistd.h>

 #include <atomic>
 #include <new>

 #include <unwindstack/MachineArm.h>
 #include <unwindstack/MachineArm64.h>
 #include <unwindstack/MachineMips.h>
 #include <unwindstack/MachineMips64.h>
 #include <unwindstack/MachineX86.h>
 #include <unwindstack/MachineX86_64.h>
 #include <unwindstack/Regs.h>
 #include <unwindstack/RegsGetLocal.h>

 #include "perfetto/base/logging.h"
 #include "perfetto/base/scoped_file.h"
 #include "perfetto/base/unix_socket.h"
 #include "perfetto/base/utils.h"
 #include "src/profiling/memory/sampler.h"
 #include "src/profiling/memory/wire_protocol.h"

 namespace perfetto {
 namespace profiling {
 namespace {

 constexpr struct timeval kSendTimeout = {1 /* s */, 0 /* us */};

 #if !PERFETTO_BUILDFLAG(PERFETTO_OS_ANDROID)
 // glibc does not define a wrapper around gettid, bionic does.
 pid_t gettid() {
   return static_cast<pid_t>(syscall(__NR_gettid));
 }
 #endif

 std::vector<base::ScopedFile> ConnectPool(const std::string& sock_name,
                                           size_t n) {
   sockaddr_un addr;
   socklen_t addr_size;
   if (!base::MakeSockAddr(sock_name, &addr, &addr_size))
     return {};

   std::vector<base::ScopedFile> res;
   res.reserve(n);
   for (size_t i = 0; i < n; ++i) {
     auto sock = base::CreateSocket();
     if (connect(*sock, reinterpret_cast<sockaddr*>(&addr), addr_size) == -1) {
       PERFETTO_PLOG("Failed to connect to %s", sock_name.c_str());
       continue;
     }
     if (setsockopt(*sock, SOL_SOCKET, SO_SNDTIMEO,
                    reinterpret_cast<const char*>(&kSendTimeout),
                    sizeof(kSendTimeout)) != 0) {
       PERFETTO_PLOG("Failed to set timeout for %s", sock_name.c_str());
       continue;
     }
     res.emplace_back(std::move(sock));
   }
   return res;
 }

 inline bool IsMainThread() {
   return getpid() == gettid();
 }

 // TODO(b/117203899): Remove this after making bionic implementation safe to
 // use.
 char* FindMainThreadStack() {
   base::ScopedFstream maps(fopen("/proc/self/maps", "r"));
   if (!maps) {
     return nullptr;
   }
   while (!feof(*maps)) {
     char line[1024];
     char* data = fgets(line, sizeof(line), *maps);
     if (data != nullptr && strstr(data, "[stack]")) {
       char* sep = strstr(data, "-");
       if (sep == nullptr)
         continue;
       sep++;
       return reinterpret_cast<char*>(strtoll(sep, nullptr, 16));
     }
   }
   return nullptr;
 }

 }  // namespace

 void FreePage::Add(const uint64_t addr,
                    const uint64_t sequence_number,
                    SocketPool* pool) {
   std::lock_guard<std::mutex> l(mutex_);
   if (offset_ == kFreePageSize) {
     FlushLocked(pool);
     // Now that we have flushed, reset to after the header.
     offset_ = 0;
   }
   FreePageEntry& current_entry = free_page_.entries[offset_++];
   current_entry.sequence_number = sequence_number;
   current_entry.addr = addr;
 }

 void FreePage::FlushLocked(SocketPool* pool) {
   WireMessage msg = {};
   msg.record_type = RecordType::Free;
   free_page_.num_entries = offset_;
   msg.free_header = &free_page_;
   BorrowedSocket fd(pool->Borrow());
   if (!fd || !SendWireMessage(*fd, msg)) {
     PERFETTO_DFATAL("Failed to send wire message");
     fd.Close();
   }
 }

 SocketPool::SocketPool(std::vector<base::ScopedFile> sockets)
     : sockets_(std::move(sockets)), available_sockets_(sockets_.size()) {}

 BorrowedSocket SocketPool::Borrow() {
   std::unique_lock<std::mutex> lck_(mutex_);
   cv_.wait(lck_, [this] {
     return available_sockets_ > 0 || dead_sockets_ == sockets_.size() ||
            shutdown_;
   });

   if (dead_sockets_ == sockets_.size() || shutdown_) {
     return {base::ScopedFile(), nullptr};
   }

   PERFETTO_CHECK(available_sockets_ > 0);
   return {std::move(sockets_[--available_sockets_]), this};
 }

 void SocketPool::Return(base::ScopedFile sock) {
   std::unique_lock<std::mutex> lck_(mutex_);
   PERFETTO_CHECK(dead_sockets_ + available_sockets_ < sockets_.size());
   if (sock && !shutdown_) {
     PERFETTO_CHECK(available_sockets_ < sockets_.size());
     sockets_[available_sockets_++] = std::move(sock);
     lck_.unlock();
     cv_.notify_one();
   } else {
     dead_sockets_++;
     if (dead_sockets_ == sockets_.size()) {
       lck_.unlock();
       cv_.notify_all();
     }
   }
 }

 void SocketPool::Shutdown() {
   {
     std::lock_guard<std::mutex> l(mutex_);
     for (size_t i = 0; i < available_sockets_; ++i)
       sockets_[i].reset();
     dead_sockets_ += available_sockets_;
     available_sockets_ = 0;
     shutdown_ = true;
   }
   cv_.notify_all();
 }

 const char* GetThreadStackBase() {
   pthread_attr_t attr;
   if (pthread_getattr_np(pthread_self(), &attr) != 0)
     return nullptr;
   base::ScopedResource<pthread_attr_t*, pthread_attr_destroy, nullptr> cleanup(
       &attr);

   char* stackaddr;
   size_t stacksize;
   if (pthread_attr_getstack(&attr, reinterpret_cast<void**>(&stackaddr),
                             &stacksize) != 0)
     return nullptr;
   return stackaddr + stacksize;
 }

 Client::Client(std::vector<base::ScopedFile> socks)
     : pthread_key_(ThreadLocalSamplingData::KeyDestructor),
       socket_pool_(std::move(socks)),
       main_thread_stack_base_(FindMainThreadStack()) {
   PERFETTO_DCHECK(pthread_key_.valid());

   uint64_t size = 0;
   base::ScopedFile maps(base::OpenFile("/proc/self/maps", O_RDONLY));
   base::ScopedFile mem(base::OpenFile("/proc/self/mem", O_RDONLY));
   if (!maps || !mem) {
     PERFETTO_DFATAL("Failed to open /proc/self/{maps,mem}");
     return;
   }
   int fds[2];
   fds[0] = *maps;
   fds[1] = *mem;
   auto fd = socket_pool_.Borrow();
   if (!fd)
     return;
   // Send an empty record to transfer fds for /proc/self/maps and
   // /proc/self/mem.
   if (base::SockSend(*fd, &size, sizeof(size), fds, 2) != sizeof(size)) {
     PERFETTO_DFATAL("Failed to send file descriptors.");
     return;
   }
   if (recv(*fd, &client_config_, sizeof(client_config_), 0) !=
       sizeof(client_config_)) {
     PERFETTO_DFATAL("Failed to receive client config.");
     return;
   }
   PERFETTO_DCHECK(client_config_.interval >= 1);
   PERFETTO_DLOG("Initialized client.");
   inited_.store(true, std::memory_order_release);
 }

 Client::Client(const std::string& sock_name, size_t conns)
     : Client(ConnectPool(sock_name, conns)) {}

 const char* Client::GetStackBase() {
   if (IsMainThread()) {
     if (!main_thread_stack_base_)
       // Because pthread_attr_getstack reads and parses /proc/self/maps and
       // /proc/self/stat, we have to cache the result here.
       main_thread_stack_base_ = GetThreadStackBase();
     return main_thread_stack_base_;
   }
   return GetThreadStackBase();
 }

 // The stack grows towards numerically smaller addresses, so the stack layout
 // of main calling malloc is as follows.
 //
 //               +------------+
 //               |SendWireMsg |
 // stacktop +--> +------------+ 0x1000
 //               |RecordMalloc|    +
 //               +------------+    |
 //               | malloc     |    |
 //               +------------+    |
 //               |  main      |    v
 // stackbase +-> +------------+ 0xffff
 void Client::RecordMalloc(uint64_t alloc_size,
                           uint64_t total_size,
                           uint64_t alloc_address) {
   if (!inited_.load(std::memory_order_acquire))
     return;
   AllocMetadata metadata;
   const char* stackbase = GetStackBase();
   const char* stacktop = reinterpret_cast<char*>(__builtin_frame_address(0));
   unwindstack::AsmGetRegs(metadata.register_data);

   if (stackbase < stacktop) {
     PERFETTO_DFATAL("Stackbase >= stacktop.");
     return;
   }

   uint64_t stack_size = static_cast<uint64_t>(stackbase - stacktop);
   metadata.total_size = total_size;
   metadata.alloc_size = alloc_size;
   metadata.alloc_address = alloc_address;
   metadata.stack_pointer = reinterpret_cast<uint64_t>(stacktop);
   metadata.stack_pointer_offset = sizeof(AllocMetadata);
   metadata.arch = unwindstack::Regs::CurrentArch();
   metadata.sequence_number =
       1 + sequence_number_.fetch_add(1, std::memory_order_acq_rel);

   WireMessage msg{};
   msg.record_type = RecordType::Malloc;
   msg.alloc_header = &metadata;
   msg.payload = const_cast<char*>(stacktop);
   msg.payload_size = static_cast<size_t>(stack_size);

   BorrowedSocket fd = socket_pool_.Borrow();
   if (!fd || !SendWireMessage(*fd, msg)) {
     PERFETTO_DFATAL("Failed to send wire message.");
     fd.Close();
   }
 }

 void Client::RecordFree(uint64_t alloc_address) {
   if (!inited_.load(std::memory_order_acquire))
     return;
   free_page_.Add(alloc_address,
                  1 + sequence_number_.fetch_add(1, std::memory_order_acq_rel),
                  &socket_pool_);
 }

 size_t Client::ShouldSampleAlloc(uint64_t alloc_size,
                                  void* (*unhooked_malloc)(size_t),
                                  void (*unhooked_free)(void*)) {
   if (!inited_.load(std::memory_order_acquire))
     return false;
   return SampleSize(pthread_key_.get(), alloc_size, client_config_.interval,
                     unhooked_malloc, unhooked_free);
 }

 void Client::MaybeSampleAlloc(uint64_t alloc_size,
                               uint64_t alloc_address,
                               void* (*unhooked_malloc)(size_t),
                               void (*unhooked_free)(void*)) {
   size_t total_size =
       ShouldSampleAlloc(alloc_size, unhooked_malloc, unhooked_free);
   if (total_size > 0)
     RecordMalloc(alloc_size, total_size, alloc_address);
 }

 void Client::Shutdown() {
   socket_pool_.Shutdown();
   inited_.store(false, std::memory_order_release);
 }

 }  // namespace profiling
 }  // namespace perfetto
	/*
	* Copyright (C) 2018 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 "src/profiling/memory/client.h"

	#include <inttypes.h>
	#include <sys/socket.h>
	#include <sys/syscall.h>
	#include <sys/un.h>
	#include <unistd.h>

	#include <atomic>
	#include <new>

	#include <unwindstack/MachineArm.h>
	#include <unwindstack/MachineArm64.h>
	#include <unwindstack/MachineMips.h>
	#include <unwindstack/MachineMips64.h>
	#include <unwindstack/MachineX86.h>
	#include <unwindstack/MachineX86_64.h>
	#include <unwindstack/Regs.h>
	#include <unwindstack/RegsGetLocal.h>

	#include "perfetto/base/logging.h"
	#include "perfetto/base/scoped_file.h"
	#include "perfetto/base/unix_socket.h"
	#include "perfetto/base/utils.h"
	#include "src/profiling/memory/sampler.h"
	#include "src/profiling/memory/wire_protocol.h"

	namespace perfetto {
	namespace profiling {
	namespace {

	constexpr struct timeval kSendTimeout = {1 /* s /, 0 / us */};

	#if !PERFETTO_BUILDFLAG(PERFETTO_OS_ANDROID)
	// glibc does not define a wrapper around gettid, bionic does.
	pid_t gettid() {
	return static_cast<pid_t>(syscall(__NR_gettid));
	}
	#endif

	std::vector<base::ScopedFile> ConnectPool(const std::string& sock_name,
	size_t n) {
	sockaddr_un addr;
	socklen_t addr_size;
	if (!base::MakeSockAddr(sock_name, &addr, &addr_size))
	return {};

	std::vector<base::ScopedFile> res;
	res.reserve(n);
	for (size_t i = 0; i < n; ++i) {
	auto sock = base::CreateSocket();
	if (connect(sock, reinterpret_cast<sockaddr>(&addr), addr_size) == -1) {
	PERFETTO_PLOG("Failed to connect to %s", sock_name.c_str());
	continue;
	}
	if (setsockopt(*sock, SOL_SOCKET, SO_SNDTIMEO,
	reinterpret_cast<const char*>(&kSendTimeout),
	sizeof(kSendTimeout)) != 0) {
	PERFETTO_PLOG("Failed to set timeout for %s", sock_name.c_str());
	continue;
	}
	res.emplace_back(std::move(sock));
	}
	return res;
	}

	inline bool IsMainThread() {
	return getpid() == gettid();
	}

	// TODO(b/117203899): Remove this after making bionic implementation safe to
	// use.
	char* FindMainThreadStack() {
	base::ScopedFstream maps(fopen("/proc/self/maps", "r"));
	if (!maps) {
	return nullptr;
	}
	while (!feof(*maps)) {
	char line[1024];
	char* data = fgets(line, sizeof(line), *maps);
	if (data != nullptr && strstr(data, "[stack]")) {
	char* sep = strstr(data, "-");
	if (sep == nullptr)
	continue;
	sep++;
	return reinterpret_cast<char*>(strtoll(sep, nullptr, 16));
	}
	}
	return nullptr;
	}

	} // namespace

	void FreePage::Add(const uint64_t addr,
	const uint64_t sequence_number,
	SocketPool* pool) {
	std::lock_guard<std::mutex> l(mutex_);
	if (offset_ == kFreePageSize) {
	FlushLocked(pool);
	// Now that we have flushed, reset to after the header.
	offset_ = 0;
	}
	FreePageEntry& current_entry = free_page_.entries[offset_++];
	current_entry.sequence_number = sequence_number;
	current_entry.addr = addr;
	}

	void FreePage::FlushLocked(SocketPool* pool) {
	WireMessage msg = {};
	msg.record_type = RecordType::Free;
	free_page_.num_entries = offset_;
	msg.free_header = &free_page_;
	BorrowedSocket fd(pool->Borrow());
	if (!fd \|\| !SendWireMessage(*fd, msg)) {
	PERFETTO_DFATAL("Failed to send wire message");
	fd.Close();
	}
	}

	SocketPool::SocketPool(std::vector<base::ScopedFile> sockets)
	: sockets_(std::move(sockets)), available_sockets_(sockets_.size()) {}

	BorrowedSocket SocketPool::Borrow() {
	std::unique_lock<std::mutex> lck_(mutex_);
	cv_.wait(lck_, [this] {
	return available_sockets_ > 0 \|\| dead_sockets_ == sockets_.size() \|\|
	shutdown_;
	});

	if (dead_sockets_ == sockets_.size() \|\| shutdown_) {
	return {base::ScopedFile(), nullptr};
	}

	PERFETTO_CHECK(available_sockets_ > 0);
	return {std::move(sockets_[--available_sockets_]), this};
	}

	void SocketPool::Return(base::ScopedFile sock) {
	std::unique_lock<std::mutex> lck_(mutex_);
	PERFETTO_CHECK(dead_sockets_ + available_sockets_ < sockets_.size());
	if (sock && !shutdown_) {
	PERFETTO_CHECK(available_sockets_ < sockets_.size());
	sockets_[available_sockets_++] = std::move(sock);
	lck_.unlock();
	cv_.notify_one();
	} else {
	dead_sockets_++;
	if (dead_sockets_ == sockets_.size()) {
	lck_.unlock();
	cv_.notify_all();
	}
	}
	}

	void SocketPool::Shutdown() {
	{
	std::lock_guard<std::mutex> l(mutex_);
	for (size_t i = 0; i < available_sockets_; ++i)
	sockets_[i].reset();
	dead_sockets_ += available_sockets_;
	available_sockets_ = 0;
	shutdown_ = true;
	}
	cv_.notify_all();
	}

	const char* GetThreadStackBase() {
	pthread_attr_t attr;
	if (pthread_getattr_np(pthread_self(), &attr) != 0)
	return nullptr;
	base::ScopedResource<pthread_attr_t*, pthread_attr_destroy, nullptr> cleanup(
	&attr);

	char* stackaddr;
	size_t stacksize;
	if (pthread_attr_getstack(&attr, reinterpret_cast<void**>(&stackaddr),
	&stacksize) != 0)
	return nullptr;
	return stackaddr + stacksize;
	}

	Client::Client(std::vector<base::ScopedFile> socks)
	: pthread_key_(ThreadLocalSamplingData::KeyDestructor),
	socket_pool_(std::move(socks)),
	main_thread_stack_base_(FindMainThreadStack()) {
	PERFETTO_DCHECK(pthread_key_.valid());

	uint64_t size = 0;
	base::ScopedFile maps(base::OpenFile("/proc/self/maps", O_RDONLY));
	base::ScopedFile mem(base::OpenFile("/proc/self/mem", O_RDONLY));
	if (!maps \|\| !mem) {
	PERFETTO_DFATAL("Failed to open /proc/self/{maps,mem}");
	return;
	}
	int fds[2];
	fds[0] = *maps;
	fds[1] = *mem;
	auto fd = socket_pool_.Borrow();
	if (!fd)
	return;
	// Send an empty record to transfer fds for /proc/self/maps and
	// /proc/self/mem.
	if (base::SockSend(*fd, &size, sizeof(size), fds, 2) != sizeof(size)) {
	PERFETTO_DFATAL("Failed to send file descriptors.");
	return;
	}
	if (recv(*fd, &client_config_, sizeof(client_config_), 0) !=
	sizeof(client_config_)) {
	PERFETTO_DFATAL("Failed to receive client config.");
	return;
	}
	PERFETTO_DCHECK(client_config_.interval >= 1);
	PERFETTO_DLOG("Initialized client.");
	inited_.store(true, std::memory_order_release);
	}

	Client::Client(const std::string& sock_name, size_t conns)
	: Client(ConnectPool(sock_name, conns)) {}

	const char* Client::GetStackBase() {
	if (IsMainThread()) {
	if (!main_thread_stack_base_)
	// Because pthread_attr_getstack reads and parses /proc/self/maps and
	// /proc/self/stat, we have to cache the result here.
	main_thread_stack_base_ = GetThreadStackBase();
	return main_thread_stack_base_;
	}
	return GetThreadStackBase();
	}

	// The stack grows towards numerically smaller addresses, so the stack layout
	// of main calling malloc is as follows.
	//
	// +------------+
	// \|SendWireMsg \|
	// stacktop +--> +------------+ 0x1000
	// \|RecordMalloc\| +
	// +------------+ \|
	// \| malloc \| \|
	// +------------+ \|
	// \| main \| v
	// stackbase +-> +------------+ 0xffff
	void Client::RecordMalloc(uint64_t alloc_size,
	uint64_t total_size,
	uint64_t alloc_address) {
	if (!inited_.load(std::memory_order_acquire))
	return;
	AllocMetadata metadata;
	const char* stackbase = GetStackBase();
	const char* stacktop = reinterpret_cast<char*>(__builtin_frame_address(0));
	unwindstack::AsmGetRegs(metadata.register_data);

	if (stackbase < stacktop) {
	PERFETTO_DFATAL("Stackbase >= stacktop.");
	return;
	}

	uint64_t stack_size = static_cast<uint64_t>(stackbase - stacktop);
	metadata.total_size = total_size;
	metadata.alloc_size = alloc_size;
	metadata.alloc_address = alloc_address;
	metadata.stack_pointer = reinterpret_cast<uint64_t>(stacktop);
	metadata.stack_pointer_offset = sizeof(AllocMetadata);
	metadata.arch = unwindstack::Regs::CurrentArch();
	metadata.sequence_number =
	1 + sequence_number_.fetch_add(1, std::memory_order_acq_rel);

	WireMessage msg{};
	msg.record_type = RecordType::Malloc;
	msg.alloc_header = &metadata;
	msg.payload = const_cast<char*>(stacktop);
	msg.payload_size = static_cast<size_t>(stack_size);

	BorrowedSocket fd = socket_pool_.Borrow();
	if (!fd \|\| !SendWireMessage(*fd, msg)) {
	PERFETTO_DFATAL("Failed to send wire message.");
	fd.Close();
	}
	}

	void Client::RecordFree(uint64_t alloc_address) {
	if (!inited_.load(std::memory_order_acquire))
	return;
	free_page_.Add(alloc_address,
	1 + sequence_number_.fetch_add(1, std::memory_order_acq_rel),
	&socket_pool_);
	}

	size_t Client::ShouldSampleAlloc(uint64_t alloc_size,
	void* (*unhooked_malloc)(size_t),
	void (unhooked_free)(void)) {
	if (!inited_.load(std::memory_order_acquire))
	return false;
	return SampleSize(pthread_key_.get(), alloc_size, client_config_.interval,
	unhooked_malloc, unhooked_free);
	}

	void Client::MaybeSampleAlloc(uint64_t alloc_size,
	uint64_t alloc_address,
	void* (*unhooked_malloc)(size_t),
	void (unhooked_free)(void)) {
	size_t total_size =
	ShouldSampleAlloc(alloc_size, unhooked_malloc, unhooked_free);
	if (total_size > 0)
	RecordMalloc(alloc_size, total_size, alloc_address);
	}

	void Client::Shutdown() {
	socket_pool_.Shutdown();
	inited_.store(false, std::memory_order_release);
	}

	} // namespace profiling
	} // namespace perfetto