libmeminfo/procmeminfo.cpp - android_system_core - 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 <errno.h>
 #include <fcntl.h>
 #include <inttypes.h>
 #include <linux/kernel-page-flags.h>
 #include <stdio.h>
 #include <unistd.h>

 #include <fstream>
 #include <iostream>
 #include <memory>
 #include <string>
 #include <utility>

 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
 #include <android-base/unique_fd.h>
 #include <procinfo/process_map.h>

 #include "meminfo_private.h"

 namespace android {
 namespace meminfo {

 static void add_mem_usage(MemUsage* to, const MemUsage& from) {
     to->vss += from.vss;
     to->rss += from.rss;
     to->pss += from.pss;
     to->uss += from.uss;

     to->swap += from.swap;

     to->private_clean += from.private_clean;
     to->private_dirty += from.private_dirty;

     to->shared_clean += from.shared_clean;
     to->shared_dirty += from.shared_dirty;
 }

 bool ProcMemInfo::ResetWorkingSet(pid_t pid) {
     std::string clear_refs_path = ::android::base::StringPrintf("/proc/%d/clear_refs", pid);
     if (!::android::base::WriteStringToFile("1\n", clear_refs_path)) {
         PLOG(ERROR) << "Failed to write to " << clear_refs_path;
         return false;
     }

     return true;
 }

 ProcMemInfo::ProcMemInfo(pid_t pid, bool get_wss, uint64_t pgflags, uint64_t pgflags_mask)
     : pid_(pid), get_wss_(get_wss), pgflags_(pgflags), pgflags_mask_(pgflags_mask) {}

 const std::vector<Vma>& ProcMemInfo::Maps() {
     if (maps_.empty() && !ReadMaps(get_wss_)) {
         LOG(ERROR) << "Failed to read maps for Process " << pid_;
     }

     return maps_;
 }

 const MemUsage& ProcMemInfo::Usage() {
     if (get_wss_) {
         LOG(WARNING) << "Trying to read process memory usage for " << pid_
                      << " using invalid object";
         return usage_;
     }

     if (maps_.empty() && !ReadMaps(get_wss_)) {
         LOG(ERROR) << "Failed to get memory usage for Process " << pid_;
     }

     return usage_;
 }

 const MemUsage& ProcMemInfo::Wss() {
     if (!get_wss_) {
         LOG(WARNING) << "Trying to read process working set for " << pid_
                      << " using invalid object";
         return wss_;
     }

     if (maps_.empty() && !ReadMaps(get_wss_)) {
         LOG(ERROR) << "Failed to get working set for Process " << pid_;
     }

     return wss_;
 }

 const std::vector<uint16_t>& ProcMemInfo::SwapOffsets() {
     if (get_wss_) {
         LOG(WARNING) << "Trying to read process swap offsets for " << pid_
                      << " using invalid object";
         return swap_offsets_;
     }

     if (maps_.empty() && !ReadMaps(get_wss_)) {
         LOG(ERROR) << "Failed to get swap offsets for Process " << pid_;
     }

     return swap_offsets_;
 }

 bool ProcMemInfo::ReadMaps(bool get_wss) {
     // Each object reads /proc/<pid>/maps only once. This is done to make sure programs that are
     // running for the lifetime of the system can recycle the objects and don't have to
     // unnecessarily retain and update this object in memory (which can get significantly large).
     // E.g. A program that only needs to reset the working set will never all ->Maps(), ->Usage().
     // E.g. A program that is monitoring smaps_rollup, may never call ->maps(), Usage(), so it
     // doesn't make sense for us to parse and retain unnecessary memory accounting stats by default.
     if (!maps_.empty()) return true;

     // parse and read /proc/<pid>/maps
     std::string maps_file = ::android::base::StringPrintf("/proc/%d/maps", pid_);
     if (!::android::procinfo::ReadMapFile(
                 maps_file, [&](uint64_t start, uint64_t end, uint16_t flags, uint64_t pgoff,
                                const char* name) {
                     maps_.emplace_back(Vma(start, end, pgoff, flags, name));
                 })) {
         LOG(ERROR) << "Failed to parse " << maps_file;
         maps_.clear();
         return false;
     }

     std::string pagemap_file = ::android::base::StringPrintf("/proc/%d/pagemap", pid_);
     ::android::base::unique_fd pagemap_fd(
             TEMP_FAILURE_RETRY(open(pagemap_file.c_str(), O_RDONLY | O_CLOEXEC)));
     if (pagemap_fd < 0) {
         PLOG(ERROR) << "Failed to open " << pagemap_file;
         return false;
     }

     for (auto& vma : maps_) {
         if (!ReadVmaStats(pagemap_fd.get(), vma, get_wss)) {
             LOG(ERROR) << "Failed to read page map for vma " << vma.name << "[" << vma.start << "-"
                        << vma.end << "]";
             maps_.clear();
             return false;
         }
         if (get_wss) {
             add_mem_usage(&wss_, vma.wss);
         } else {
             add_mem_usage(&usage_, vma.usage);
         }
     }

     return true;
 }

 bool ProcMemInfo::ReadVmaStats(int pagemap_fd, Vma& vma, bool get_wss) {
     PageAcct& pinfo = PageAcct::Instance();
     uint64_t pagesz = getpagesize();
     uint64_t num_pages = (vma.end - vma.start) / pagesz;

     std::unique_ptr<uint64_t[]> pg_frames(new uint64_t[num_pages]);
     uint64_t first = vma.start / pagesz;
     if (pread64(pagemap_fd, pg_frames.get(), num_pages * sizeof(uint64_t),
                 first * sizeof(uint64_t)) < 0) {
         PLOG(ERROR) << "Failed to read page frames from page map for pid: " << pid_;
         return false;
     }

     std::unique_ptr<uint64_t[]> pg_flags(new uint64_t[num_pages]);
     std::unique_ptr<uint64_t[]> pg_counts(new uint64_t[num_pages]);
     for (uint64_t i = 0; i < num_pages; ++i) {
         if (!get_wss) {
             vma.usage.vss += pagesz;
         }
         uint64_t p = pg_frames[i];
         if (!PAGE_PRESENT(p) && !PAGE_SWAPPED(p)) continue;

         if (PAGE_SWAPPED(p)) {
             vma.usage.swap += pagesz;
             swap_offsets_.emplace_back(PAGE_SWAP_OFFSET(p));
             continue;
         }

         uint64_t page_frame = PAGE_PFN(p);
         if (!pinfo.PageFlags(page_frame, &pg_flags[i])) {
             LOG(ERROR) << "Failed to get page flags for " << page_frame << " in process " << pid_;
             swap_offsets_.clear();
             return false;
         }

         // skip unwanted pages from the count
         if ((pg_flags[i] & pgflags_mask_) != pgflags_) continue;

         if (!pinfo.PageMapCount(page_frame, &pg_counts[i])) {
             LOG(ERROR) << "Failed to get page count for " << page_frame << " in process " << pid_;
             swap_offsets_.clear();
             return false;
         }

         // Page was unmapped between the presence check at the beginning of the loop and here.
         if (pg_counts[i] == 0) {
             pg_frames[i] = 0;
             pg_flags[i] = 0;
             continue;
         }

         bool is_dirty = !!(pg_flags[i] & (1 << KPF_DIRTY));
         bool is_private = (pg_counts[i] == 1);
         // Working set
         if (get_wss) {
             bool is_referenced = !!(pg_flags[i] & (1 << KPF_REFERENCED));
             if (!is_referenced) {
                 continue;
             }
             // This effectively makes vss = rss for the working set is requested.
             // The libpagemap implementation returns vss > rss for
             // working set, which doesn't make sense.
             vma.wss.vss += pagesz;
             vma.wss.rss += pagesz;
             vma.wss.uss += is_private ? pagesz : 0;
             vma.wss.pss += pagesz / pg_counts[i];
             if (is_private) {
                 vma.wss.private_dirty += is_dirty ? pagesz : 0;
                 vma.wss.private_clean += is_dirty ? 0 : pagesz;
             } else {
                 vma.wss.shared_dirty += is_dirty ? pagesz : 0;
                 vma.wss.shared_clean += is_dirty ? 0 : pagesz;
             }
         } else {
             vma.usage.rss += pagesz;
             vma.usage.uss += is_private ? pagesz : 0;
             vma.usage.pss += pagesz / pg_counts[i];
             if (is_private) {
                 vma.usage.private_dirty += is_dirty ? pagesz : 0;
                 vma.usage.private_clean += is_dirty ? 0 : pagesz;
             } else {
                 vma.usage.shared_dirty += is_dirty ? pagesz : 0;
                 vma.usage.shared_clean += is_dirty ? 0 : pagesz;
             }
         }
     }

     return true;
 }

 }  // namespace meminfo
 }  // namespace android
	/*
	* 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 <errno.h>
	#include <fcntl.h>
	#include <inttypes.h>
	#include <linux/kernel-page-flags.h>
	#include <stdio.h>
	#include <unistd.h>

	#include <fstream>
	#include <iostream>
	#include <memory>
	#include <string>
	#include <utility>

	#include <android-base/file.h>
	#include <android-base/logging.h>
	#include <android-base/stringprintf.h>
	#include <android-base/unique_fd.h>
	#include <procinfo/process_map.h>

	#include "meminfo_private.h"

	namespace android {
	namespace meminfo {

	static void add_mem_usage(MemUsage* to, const MemUsage& from) {
	to->vss += from.vss;
	to->rss += from.rss;
	to->pss += from.pss;
	to->uss += from.uss;

	to->swap += from.swap;

	to->private_clean += from.private_clean;
	to->private_dirty += from.private_dirty;

	to->shared_clean += from.shared_clean;
	to->shared_dirty += from.shared_dirty;
	}

	bool ProcMemInfo::ResetWorkingSet(pid_t pid) {
	std::string clear_refs_path = ::android::base::StringPrintf("/proc/%d/clear_refs", pid);
	if (!::android::base::WriteStringToFile("1\n", clear_refs_path)) {
	PLOG(ERROR) << "Failed to write to " << clear_refs_path;
	return false;
	}

	return true;
	}

	ProcMemInfo::ProcMemInfo(pid_t pid, bool get_wss, uint64_t pgflags, uint64_t pgflags_mask)
	: pid_(pid), get_wss_(get_wss), pgflags_(pgflags), pgflags_mask_(pgflags_mask) {}

	const std::vector<Vma>& ProcMemInfo::Maps() {
	if (maps_.empty() && !ReadMaps(get_wss_)) {
	LOG(ERROR) << "Failed to read maps for Process " << pid_;
	}

	return maps_;
	}

	const MemUsage& ProcMemInfo::Usage() {
	if (get_wss_) {
	LOG(WARNING) << "Trying to read process memory usage for " << pid_
	<< " using invalid object";
	return usage_;
	}

	if (maps_.empty() && !ReadMaps(get_wss_)) {
	LOG(ERROR) << "Failed to get memory usage for Process " << pid_;
	}

	return usage_;
	}

	const MemUsage& ProcMemInfo::Wss() {
	if (!get_wss_) {
	LOG(WARNING) << "Trying to read process working set for " << pid_
	<< " using invalid object";
	return wss_;
	}

	if (maps_.empty() && !ReadMaps(get_wss_)) {
	LOG(ERROR) << "Failed to get working set for Process " << pid_;
	}

	return wss_;
	}

	const std::vector<uint16_t>& ProcMemInfo::SwapOffsets() {
	if (get_wss_) {
	LOG(WARNING) << "Trying to read process swap offsets for " << pid_
	<< " using invalid object";
	return swap_offsets_;
	}

	if (maps_.empty() && !ReadMaps(get_wss_)) {
	LOG(ERROR) << "Failed to get swap offsets for Process " << pid_;
	}

	return swap_offsets_;
	}

	bool ProcMemInfo::ReadMaps(bool get_wss) {
	// Each object reads /proc/<pid>/maps only once. This is done to make sure programs that are
	// running for the lifetime of the system can recycle the objects and don't have to
	// unnecessarily retain and update this object in memory (which can get significantly large).
	// E.g. A program that only needs to reset the working set will never all ->Maps(), ->Usage().
	// E.g. A program that is monitoring smaps_rollup, may never call ->maps(), Usage(), so it
	// doesn't make sense for us to parse and retain unnecessary memory accounting stats by default.
	if (!maps_.empty()) return true;

	// parse and read /proc/<pid>/maps
	std::string maps_file = ::android::base::StringPrintf("/proc/%d/maps", pid_);
	if (!::android::procinfo::ReadMapFile(
	maps_file, [&](uint64_t start, uint64_t end, uint16_t flags, uint64_t pgoff,
	const char* name) {
	maps_.emplace_back(Vma(start, end, pgoff, flags, name));
	})) {
	LOG(ERROR) << "Failed to parse " << maps_file;
	maps_.clear();
	return false;
	}

	std::string pagemap_file = ::android::base::StringPrintf("/proc/%d/pagemap", pid_);
	::android::base::unique_fd pagemap_fd(
	TEMP_FAILURE_RETRY(open(pagemap_file.c_str(), O_RDONLY \| O_CLOEXEC)));
	if (pagemap_fd < 0) {
	PLOG(ERROR) << "Failed to open " << pagemap_file;
	return false;
	}

	for (auto& vma : maps_) {
	if (!ReadVmaStats(pagemap_fd.get(), vma, get_wss)) {
	LOG(ERROR) << "Failed to read page map for vma " << vma.name << "[" << vma.start << "-"
	<< vma.end << "]";
	maps_.clear();
	return false;
	}
	if (get_wss) {
	add_mem_usage(&wss_, vma.wss);
	} else {
	add_mem_usage(&usage_, vma.usage);
	}
	}

	return true;
	}

	bool ProcMemInfo::ReadVmaStats(int pagemap_fd, Vma& vma, bool get_wss) {
	PageAcct& pinfo = PageAcct::Instance();
	uint64_t pagesz = getpagesize();
	uint64_t num_pages = (vma.end - vma.start) / pagesz;

	std::unique_ptr<uint64_t[]> pg_frames(new uint64_t[num_pages]);
	uint64_t first = vma.start / pagesz;
	if (pread64(pagemap_fd, pg_frames.get(), num_pages * sizeof(uint64_t),
	first * sizeof(uint64_t)) < 0) {
	PLOG(ERROR) << "Failed to read page frames from page map for pid: " << pid_;
	return false;
	}

	std::unique_ptr<uint64_t[]> pg_flags(new uint64_t[num_pages]);
	std::unique_ptr<uint64_t[]> pg_counts(new uint64_t[num_pages]);
	for (uint64_t i = 0; i < num_pages; ++i) {
	if (!get_wss) {
	vma.usage.vss += pagesz;
	}
	uint64_t p = pg_frames[i];
	if (!PAGE_PRESENT(p) && !PAGE_SWAPPED(p)) continue;

	if (PAGE_SWAPPED(p)) {
	vma.usage.swap += pagesz;
	swap_offsets_.emplace_back(PAGE_SWAP_OFFSET(p));
	continue;
	}

	uint64_t page_frame = PAGE_PFN(p);
	if (!pinfo.PageFlags(page_frame, &pg_flags[i])) {
	LOG(ERROR) << "Failed to get page flags for " << page_frame << " in process " << pid_;
	swap_offsets_.clear();
	return false;
	}

	// skip unwanted pages from the count
	if ((pg_flags[i] & pgflags_mask_) != pgflags_) continue;

	if (!pinfo.PageMapCount(page_frame, &pg_counts[i])) {
	LOG(ERROR) << "Failed to get page count for " << page_frame << " in process " << pid_;
	swap_offsets_.clear();
	return false;
	}

	// Page was unmapped between the presence check at the beginning of the loop and here.
	if (pg_counts[i] == 0) {
	pg_frames[i] = 0;
	pg_flags[i] = 0;
	continue;
	}

	bool is_dirty = !!(pg_flags[i] & (1 << KPF_DIRTY));
	bool is_private = (pg_counts[i] == 1);
	// Working set
	if (get_wss) {
	bool is_referenced = !!(pg_flags[i] & (1 << KPF_REFERENCED));
	if (!is_referenced) {
	continue;
	}
	// This effectively makes vss = rss for the working set is requested.
	// The libpagemap implementation returns vss > rss for
	// working set, which doesn't make sense.
	vma.wss.vss += pagesz;
	vma.wss.rss += pagesz;
	vma.wss.uss += is_private ? pagesz : 0;
	vma.wss.pss += pagesz / pg_counts[i];
	if (is_private) {
	vma.wss.private_dirty += is_dirty ? pagesz : 0;
	vma.wss.private_clean += is_dirty ? 0 : pagesz;
	} else {
	vma.wss.shared_dirty += is_dirty ? pagesz : 0;
	vma.wss.shared_clean += is_dirty ? 0 : pagesz;
	}
	} else {
	vma.usage.rss += pagesz;
	vma.usage.uss += is_private ? pagesz : 0;
	vma.usage.pss += pagesz / pg_counts[i];
	if (is_private) {
	vma.usage.private_dirty += is_dirty ? pagesz : 0;
	vma.usage.private_clean += is_dirty ? 0 : pagesz;
	} else {
	vma.usage.shared_dirty += is_dirty ? pagesz : 0;
	vma.usage.shared_clean += is_dirty ? 0 : pagesz;
	}
	}
	}

	return true;
	}

	} // namespace meminfo
	} // namespace android