generic-library/bionic
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Optimize dlopen from a zip file

Browse Source 
This change makes dynamic linker reuse ZipArchiveHandles in
ld_library_path on dlopen to optimize the lookup of dt_needed
libraries.

Bug: http://b/21960534
Change-Id: I65f897910d46dd2ffabdcb0b7842db2f127eee30
This commit is contained in:
Dmitriy Ivanov
2015-09-28 16:38:31 -07:00
parent 8b279eadd3
commit b48275045d
4 changed files with 118 additions and 39 deletions
Download Patch File Download Diff File Expand all files Collapse all files

86
linker/linker.cpp
View File

@@ -41,6 +41,7 @@
#include <new>
#include <string>
#include <unordered_map>
#include <vector>
// Private C library headers.
@@ -1121,7 +1122,50 @@ ElfW(Sym)* soinfo::elf_addr_lookup(const void* addr) {
return nullptr;
}
static int open_library_in_zipfile(const char* const path,
class ZipArchiveCache {
public:
ZipArchiveCache() {}
~ZipArchiveCache();
bool get_or_open(const char* zip_path, ZipArchiveHandle* handle);
private:
DISALLOW_COPY_AND_ASSIGN(ZipArchiveCache);
std::unordered_map<std::string, ZipArchiveHandle> cache_;
};
bool ZipArchiveCache::get_or_open(const char* zip_path, ZipArchiveHandle* handle) {
std::string key(zip_path);
auto it = cache_.find(key);
if (it != cache_.end()) {
*handle = it->second;
return true;
}
int fd = TEMP_FAILURE_RETRY(open(zip_path, O_RDONLY | O_CLOEXEC));
if (fd == -1) {
return false;
}
if (OpenArchiveFd(fd, "", handle) != 0) {
// invalid zip-file (?)
close(fd);
return false;
}
cache_[key] = *handle;
return true;
}
ZipArchiveCache::~ZipArchiveCache() {
for (auto it : cache_) {
CloseArchive(it.second);
}
}
static int open_library_in_zipfile(ZipArchiveCache* zip_archive_cache,
const char* const path,
off64_t* file_offset) {
TRACE("Trying zip file open from path '%s'", path);
@@ -1150,16 +1194,12 @@ static int open_library_in_zipfile(const char* const path,
}
ZipArchiveHandle handle;
if (OpenArchiveFd(fd, "", &handle, false) != 0) {
if (!zip_archive_cache->get_or_open(zip_path, &handle)) {
// invalid zip-file (?)
close(fd);
return -1;
}
auto archive_guard = make_scope_guard([&]() {
CloseArchive(handle);
});
ZipEntry entry;
if (FindEntry(handle, ZipString(file_path), &entry) != 0) {
@@ -1205,7 +1245,8 @@ static int open_library_on_default_path(const char* name, off64_t* file_offset)
return -1;
}
static int open_library_on_paths(const char* name, off64_t* file_offset,
static int open_library_on_paths(ZipArchiveCache* zip_archive_cache,
const char* name, off64_t* file_offset,
const std::vector<std::string>& paths) {
for (const auto& path_str : paths) {
char buf[512];
@@ -1216,7 +1257,7 @@ static int open_library_on_paths(const char* name, off64_t* file_offset,
int fd = -1;
if (strstr(buf, kZipFileSeparator) != nullptr) {
fd = open_library_in_zipfile(buf, file_offset);
fd = open_library_in_zipfile(zip_archive_cache, buf, file_offset);
}
if (fd == -1) {
@@ -1234,13 +1275,15 @@ static int open_library_on_paths(const char* name, off64_t* file_offset,
return -1;
}
static int open_library(const char* name, soinfo *needed_by, off64_t* file_offset) {
static int open_library(ZipArchiveCache* zip_archive_cache,
const char* name, soinfo *needed_by,
off64_t* file_offset) {
TRACE("[ opening %s ]", name);
// If the name contains a slash, we should attempt to open it directly and not search the paths.
if (strchr(name, '/') != nullptr) {
if (strstr(name, kZipFileSeparator) != nullptr) {
int fd = open_library_in_zipfile(name, file_offset);
int fd = open_library_in_zipfile(zip_archive_cache, name, file_offset);
if (fd != -1) {
return fd;
}
@@ -1254,13 +1297,15 @@ static int open_library(const char* name, soinfo *needed_by, off64_t* file_offse
}
// Otherwise we try LD_LIBRARY_PATH first, and fall back to the built-in well known paths.
int fd = open_library_on_paths(name, file_offset, g_ld_library_paths);
int fd = open_library_on_paths(zip_archive_cache, name, file_offset, g_ld_library_paths);
if (fd == -1 && needed_by) {
fd = open_library_on_paths(name, file_offset, needed_by->get_dt_runpath());
fd = open_library_on_paths(zip_archive_cache, name, file_offset, needed_by->get_dt_runpath());
}
if (fd == -1) {
fd = open_library_on_default_path(name, file_offset);
}
return fd;
}
@@ -1367,7 +1412,8 @@ static soinfo* load_library(int fd, off64_t file_offset,
return si;
}
static soinfo* load_library(LoadTaskList& load_tasks, const char* name,
static soinfo* load_library(ZipArchiveCache* zip_archive_cache,
LoadTaskList& load_tasks, const char* name,
soinfo* needed_by, int rtld_flags,
const android_dlextinfo* extinfo) {
if (extinfo != nullptr && (extinfo->flags & ANDROID_DLEXT_USE_LIBRARY_FD) != 0) {
@@ -1380,7 +1426,7 @@ static soinfo* load_library(LoadTaskList& load_tasks, const char* name,
// Open the file.
off64_t file_offset;
int fd = open_library(name, needed_by, &file_offset);
int fd = open_library(zip_archive_cache, name, needed_by, &file_offset);
if (fd == -1) {
DL_ERR("library \"%s\" not found", name);
return nullptr;
@@ -1427,7 +1473,8 @@ static bool find_loaded_library_by_soname(const char* name, soinfo** candidate)
return false;
}
static soinfo* find_library_internal(LoadTaskList& load_tasks, const char* name,
static soinfo* find_library_internal(ZipArchiveCache* zip_archive_cache,
LoadTaskList& load_tasks, const char* name,
soinfo* needed_by, int rtld_flags,
const android_dlextinfo* extinfo) {
soinfo* candidate;
@@ -1441,7 +1488,7 @@ static soinfo* find_library_internal(LoadTaskList& load_tasks, const char* name,
TRACE("[ '%s' find_loaded_library_by_soname returned false (*candidate=%s@%p). Trying harder...]",
name, candidate == nullptr ? "n/a" : candidate->get_realpath(), candidate);
soinfo* si = load_library(load_tasks, name, needed_by, rtld_flags, extinfo);
soinfo* si = load_library(zip_archive_cache, load_tasks, name, needed_by, rtld_flags, extinfo);
// In case we were unable to load the library but there
// is a candidate loaded under the same soname but different
@@ -1521,15 +1568,18 @@ static bool find_libraries(soinfo* start_with,
}
});
ZipArchiveCache zip_archive_cache;
// Step 1: load and pre-link all DT_NEEDED libraries in breadth first order.
for (LoadTask::unique_ptr task(load_tasks.pop_front());
task.get() != nullptr; task.reset(load_tasks.pop_front())) {
soinfo* needed_by = task->get_needed_by();
bool is_dt_needed = needed_by != nullptr && (needed_by != start_with || add_as_children);
soinfo* si = find_library_internal(load_tasks, task->get_name(), needed_by,
rtld_flags,
soinfo* si = find_library_internal(&zip_archive_cache, load_tasks,
task->get_name(), needed_by, rtld_flags,
is_dt_needed ? nullptr : extinfo);
if (si == nullptr) {
return false;
}

35
tests/dlext_test.cpp
View File

@@ -52,15 +52,15 @@ typedef int (*fn)(void);
#define LIBSIZE 1024*1024 // how much address space to reserve for it
#if defined(__LP64__)
#define LIBPATH_PREFIX "/nativetest64/libdlext_test_fd/"
#define LIBPATH_PREFIX "/nativetest64/"
#else
#define LIBPATH_PREFIX "/nativetest/libdlext_test_fd/"
#define LIBPATH_PREFIX "/nativetest/"
#endif
#define LIBPATH LIBPATH_PREFIX "libdlext_test_fd.so"
#define LIBZIPPATH LIBPATH_PREFIX "libdlext_test_fd_zipaligned.zip"
#define LIBPATH LIBPATH_PREFIX "libdlext_test_fd/libdlext_test_fd.so"
#define LIBZIPPATH LIBPATH_PREFIX "libdlext_test_zip/libdlext_test_zip_zipaligned.zip"
#define LIBZIP_OFFSET 2*PAGE_SIZE
#define LIBZIP_OFFSET PAGE_SIZE
class DlExtTest : public ::testing::Test {
protected:
@@ -131,9 +131,9 @@ TEST_F(DlExtTest, ExtInfoUseFdWithOffset) {
handle_ = android_dlopen_ext(lib_path.c_str(), RTLD_NOW, &extinfo);
ASSERT_DL_NOTNULL(handle_);
fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
ASSERT_DL_NOTNULL(f);
EXPECT_EQ(4, f());
uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle_, "dlopen_testlib_taxicab_number"));
ASSERT_DL_NOTNULL(taxicab_number);
EXPECT_EQ(1729U, *taxicab_number);
}
TEST_F(DlExtTest, ExtInfoUseFdWithInvalidOffset) {
@@ -163,7 +163,7 @@ TEST_F(DlExtTest, ExtInfoUseFdWithInvalidOffset) {
ASSERT_TRUE(handle_ == nullptr);
ASSERT_SUBSTR("dlopen failed: file offset for the library \"libname_placeholder\" is negative", dlerror());
extinfo.library_fd_offset = PAGE_SIZE;
extinfo.library_fd_offset = 0;
handle_ = android_dlopen_ext("libname_ignored", RTLD_NOW, &extinfo);
ASSERT_TRUE(handle_ == nullptr);
ASSERT_EQ("dlopen failed: \"" + lib_realpath + "\" has bad ELF magic", dlerror());
@@ -218,13 +218,12 @@ TEST(dlext, android_dlopen_ext_force_load_soname_exception) {
TEST(dlfcn, dlopen_from_zip_absolute_path) {
const std::string lib_path = std::string(getenv("ANDROID_DATA")) + LIBZIPPATH;
void* handle = dlopen((lib_path + "!/libdir/libdlext_test_fd.so").c_str(), RTLD_NOW);
void* handle = dlopen((lib_path + "!/libdir/libatest_simple_zip.so").c_str(), RTLD_NOW);
ASSERT_TRUE(handle != nullptr) << dlerror();
int (*fn)(void);
fn = reinterpret_cast<int (*)(void)>(dlsym(handle, "getRandomNumber"));
ASSERT_TRUE(fn != nullptr);
EXPECT_EQ(4, fn());
uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle, "dlopen_testlib_taxicab_number"));
ASSERT_DL_NOTNULL(taxicab_number);
EXPECT_EQ(1729U, *taxicab_number);
dlclose(handle);
}
@@ -238,12 +237,12 @@ TEST(dlfcn, dlopen_from_zip_ld_library_path) {
ASSERT_TRUE(android_update_LD_LIBRARY_PATH != nullptr) << dlerror();
void* handle = dlopen("libdlext_test_fd.so", RTLD_NOW);
void* handle = dlopen("libdlext_test_zip.so", RTLD_NOW);
ASSERT_TRUE(handle == nullptr);
android_update_LD_LIBRARY_PATH(lib_path.c_str());
handle = dlopen("libdlext_test_fd.so", RTLD_NOW);
handle = dlopen("libdlext_test_zip.so", RTLD_NOW);
ASSERT_TRUE(handle != nullptr) << dlerror();
int (*fn)(void);
@@ -251,6 +250,10 @@ TEST(dlfcn, dlopen_from_zip_ld_library_path) {
ASSERT_TRUE(fn != nullptr);
EXPECT_EQ(4, fn());
uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle, "dlopen_testlib_taxicab_number"));
ASSERT_DL_NOTNULL(taxicab_number);
EXPECT_EQ(1729U, *taxicab_number);
dlclose(handle);
}

10
tests/libs/Android.build.dlext_testzip.mk
View File

@@ -21,21 +21,21 @@
include $(CLEAR_VARS)
LOCAL_MODULE_CLASS := SHARED_LIBRARIES
LOCAL_MODULE := libdlext_test_fd_zipaligned
LOCAL_MODULE := libdlext_test_zip_zipaligned
LOCAL_MODULE_SUFFIX := .zip
LOCAL_MODULE_TAGS := tests
LOCAL_MODULE_PATH := $($(bionic_2nd_arch_prefix)TARGET_OUT_DATA_NATIVE_TESTS)/libdlext_test_fd
LOCAL_MODULE_PATH := $($(bionic_2nd_arch_prefix)TARGET_OUT_DATA_NATIVE_TESTS)/libdlext_test_zip
LOCAL_2ND_ARCH_VAR_PREFIX := $(bionic_2nd_arch_prefix)
include $(BUILD_SYSTEM)/base_rules.mk
my_shared_libs := \
$($(bionic_2nd_arch_prefix)TARGET_OUT_INTERMEDIATE_LIBRARIES)/libdlext_test_fd.so
$($(bionic_2nd_arch_prefix)TARGET_OUT_INTERMEDIATE_LIBRARIES)/libdlext_test_zip.so \
$($(bionic_2nd_arch_prefix)TARGET_OUT_INTERMEDIATE_LIBRARIES)/libatest_simple_zip.so
$(LOCAL_BUILT_MODULE): PRIVATE_ALIGNMENT := 4096 # PAGE_SIZE
$(LOCAL_BUILT_MODULE) : $(my_shared_libs) | $(ZIPALIGN)
@echo "Zipalign $(PRIVATE_ALIGNMENT): $@"
$(hide) rm -rf $(dir $@) && mkdir -p $(dir $@)/libdir
$(hide) cp $^ $(dir $@)/libdir
$(hide) (cd $(dir $@) && touch empty_file.txt && zip -qrD0 $(notdir $@).unaligned empty_file.txt libdir/*.so)
$(hide) $(ZIPALIGN) $(PRIVATE_ALIGNMENT) $@.unaligned $@
$(hide) $(ZIPALIGN) -p 4 $@.unaligned $@

26
tests/libs/Android.mk
View File

@@ -126,6 +126,32 @@ build_type := target
build_target := SHARED_LIBRARY
include $(TEST_PATH)/Android.build.mk
# -----------------------------------------------------------------------------
# Libraries used by dlext tests for open from a zip-file
# -----------------------------------------------------------------------------
libdlext_test_zip_src_files := \
dlext_test_library.cpp \
libdlext_test_zip_shared_libraries := libatest_simple_zip
libdlext_test_zip_install_to_out_data := true
module := libdlext_test_zip
module_tag := optional
build_type := target
build_target := SHARED_LIBRARY
include $(TEST_PATH)/Android.build.mk
libatest_simple_zip_src_files := \
dlopen_testlib_simple.cpp
libatest_simple_zip_install_to_out_data := true
module := libatest_simple_zip
module_tag := optional
build_type := target
build_target := SHARED_LIBRARY
include $(TEST_PATH)/Android.build.mk
# ----------------------------------------------------------------------------
# Library with soname which does not match filename
# ----------------------------------------------------------------------------