Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 3841accb authored by Yabin Cui's avatar Yabin Cui
Browse files

libprocinfo: add functions reading process map file. 

Add test and benchmark.
Also switch libbacktrace, libunwindstack, libmemunreachable
to use libprocinfo for map file reading.
The benchmark shows using libprocinfo speeds up map file reading
in libbacktrace and libunwindstack 18% - 36% on walleye.

Bug: http://b/79118393
Test: run procinfo_test.
Test: run libunwindstack_test.
Test: run libbacktrace_test.
Test: run memunreachable_test.

Change-Id: Icf281c352f4103fc8d4ba6732c5c07b943330ca1
parent 3607fe67

libbacktrace/Android.bp

+4 −1
Original line number Diff line number Diff line
@@ -91,7 +91,10 @@ cc_library { 
                "libdexfile",

            ],



            static_libs: ["libcutils"],

            static_libs: [

                "libcutils",

                "libprocinfo",

            ],



            // libdexfile will eventually properly export headers, for now

            // include these directly.

libbacktrace/BacktraceMap.cpp

+16 −24
Original line number Diff line number Diff line
@@ -28,6 +28,9 @@ 
#include <backtrace/Backtrace.h>

#include <backtrace/BacktraceMap.h>

#include <backtrace/backtrace_constants.h>

#if defined(__linux__)

#include <procinfo/process_map.h>

#endif



#include "thread_utils.h"
@@ -60,27 +63,19 @@ void BacktraceMap::FillIn(uint64_t addr, backtrace_map_t* map) { 
  *map = {};

}



bool BacktraceMap::ParseLine(const char* line, backtrace_map_t* map) {

#if defined(__APPLE__)

static bool ParseLine(const char* line, backtrace_map_t* map) {

  uint64_t start;

  uint64_t end;

  char permissions[5];

  int name_pos;



#if defined(__APPLE__)

// Mac OS vmmap(1) output:

// __TEXT                 0009f000-000a1000 [    8K     8K] r-x/rwx SM=COW  /Volumes/android/dalvik-dev/out/host/darwin-x86/bin/libcorkscrew_test\n

// 012345678901234567890123456789012345678901234567890123456789

// 0         1         2         3         4         5

  if (sscanf(line, "%*21c %" SCNx64 "-%" SCNx64 " [%*13c] %3c/%*3c SM=%*3c  %n",

             &start, &end, permissions, &name_pos) != 3) {

#else

// Linux /proc/<pid>/maps lines:

// 6f000000-6f01e000 rwxp 00000000 00:0c 16389419   /system/lib/libcomposer.so\n

// 012345678901234567890123456789012345678901234567890123456789

// 0         1         2         3         4         5

  if (sscanf(line, "%" SCNx64 "-%" SCNx64 " %4s %*x %*x:%*x %*d %n",

             &start, &end, permissions, &name_pos) != 3) {

#endif

    return false;

  }
@@ -107,24 +102,15 @@ bool BacktraceMap::ParseLine(const char* line, backtrace_map_t* map) { 
        map->flags, map->name.c_str());

  return true;

}

#endif  // defined(__APPLE__)



bool BacktraceMap::Build() {

#if defined(__APPLE__)

  char cmd[sizeof(pid_t)*3 + sizeof("vmmap -w -resident -submap -allSplitLibs -interleaved ") + 1];

#else

  char path[sizeof(pid_t)*3 + sizeof("/proc//maps") + 1];

#endif

  char line[1024];



#if defined(__APPLE__)

  // cmd is guaranteed to always be big enough to hold this string.

  snprintf(cmd, sizeof(cmd), "vmmap -w -resident -submap -allSplitLibs -interleaved %d", pid_);

  FILE* fp = popen(cmd, "r");

#else

  // path is guaranteed to always be big enough to hold this string.

  snprintf(path, sizeof(path), "/proc/%d/maps", pid_);

  FILE* fp = fopen(path, "r");

#endif

  if (fp == nullptr) {

    return false;

  }
@@ -135,13 +121,19 @@ bool BacktraceMap::Build() { 
      maps_.push_back(map);

    }

  }

#if defined(__APPLE__)

  pclose(fp);

  return true;

#else

  fclose(fp);

  return android::procinfo::ReadProcessMaps(

      pid_, [&](uint64_t start, uint64_t end, uint16_t flags, uint64_t, const char* name) {

        maps_.resize(maps_.size() + 1);

        backtrace_map_t& map = maps_.back();

        map.start = start;

        map.end = end;

        map.flags = flags;

        map.name = name;

      });

#endif



  return true;

}



#if defined(__APPLE__)

libbacktrace/include/backtrace/BacktraceMap.h

+0 −2
Original line number Diff line number Diff line
@@ -169,8 +169,6 @@ public: 


  virtual uint64_t GetLoadBias(size_t /* index */) { return 0; }



  virtual bool ParseLine(const char* line, backtrace_map_t* map);



  pid_t pid_;

  std::deque<backtrace_map_t> maps_;

  std::vector<std::string> suffixes_to_ignore_;

libmemunreachable/Android.bp

+1 −1
Original line number Diff line number Diff line
@@ -29,7 +29,6 @@ cc_library { 
        "HeapWalker.cpp",

        "LeakFolding.cpp",

        "LeakPipe.cpp",

        "LineBuffer.cpp",

        "MemUnreachable.cpp",

        "ProcessMappings.cpp",

        "PtracerThread.cpp",
@@ -38,6 +37,7 @@ cc_library { 


    static_libs: [

        "libc_malloc_debug_backtrace",

        "libprocinfo",

    ],

    // Only need this for arm since libc++ uses its own unwind code that

    // doesn't mix with the other default unwind code.

libmemunreachable/LineBuffer.cpp

deleted100644 → 0
+0 −66
Original line number Diff line number Diff line 
/*

 * 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.

 */



// Copied from system/extras/memory_replay/LineBuffer.cpp

// TODO(ccross): find a way to share between libmemunreachable and memory_replay?



#include <errno.h>

#include <string.h>

#include <unistd.h>



#include "LineBuffer.h"



namespace android {



LineBuffer::LineBuffer(int fd, char* buffer, size_t buffer_len)

    : fd_(fd), buffer_(buffer), buffer_len_(buffer_len) {}



bool LineBuffer::GetLine(char** line, size_t* line_len) {

  while (true) {

    if (bytes_ > 0) {

      char* newline = reinterpret_cast<char*>(memchr(buffer_ + start_, '\n', bytes_));

      if (newline != nullptr) {

        *newline = '\0';

        *line = buffer_ + start_;

        start_ = newline - buffer_ + 1;

        bytes_ -= newline - *line + 1;

        *line_len = newline - *line;

        return true;

      }

    }

    if (start_ > 0) {

      // Didn't find anything, copy the current to the front of the buffer.

      memmove(buffer_, buffer_ + start_, bytes_);

      start_ = 0;

    }

    ssize_t bytes = TEMP_FAILURE_RETRY(read(fd_, buffer_ + bytes_, buffer_len_ - bytes_ - 1));

    if (bytes <= 0) {

      if (bytes_ > 0) {

        // The read data might not contain a nul terminator, so add one.

        buffer_[bytes_] = '\0';

        *line = buffer_ + start_;

        *line_len = bytes_;

        bytes_ = 0;

        start_ = 0;

        return true;

      }

      return false;

    }

    bytes_ += bytes;

  }

}



}  // namespace android