Introduce VDEX file, use it for DEX files
This patch introduces a new output file called VDEX. In the future,
VDEX files will store pre-validated DEX files which do not need to be
re-extracted and re-verified when recompiling, e.g. due to new
profiling information or after a system update.
With this CL, the OatWriter writes DEX files into the VDEX and the
rest of its output into OAT. The OatFile class and related classes
are updated to load the VDEX at runtime and mmap the DEX file section
from it. Patchoat creates symlinks to the source VDEX files in the
target directory or copies the files if passed in as file descriptors.
The feature can be disabled by setting the environment variable
ART_ENABLE_VDEX to false.
Test: m test-art-host
Bug: 30937355
Change-Id: I54dcaececf6814c258c80524ec15e2e2ef69c8dd
diff --git a/runtime/oat_file_assistant.cc b/runtime/oat_file_assistant.cc
index fe6332d..415f991 100644
--- a/runtime/oat_file_assistant.cc
+++ b/runtime/oat_file_assistant.cc
@@ -345,17 +345,6 @@
return odex_.CompilerFilter();
}
-static std::string ArtFileName(const OatFile* oat_file) {
- const std::string oat_file_location = oat_file->GetLocation();
- // Replace extension with .art
- const size_t last_ext = oat_file_location.find_last_of('.');
- if (last_ext == std::string::npos) {
- LOG(ERROR) << "No extension in oat file " << oat_file_location;
- return std::string();
- }
- return oat_file_location.substr(0, last_ext) + ".art";
-}
-
const std::string* OatFileAssistant::OatFileName() {
return oat_.Filename();
}
@@ -565,6 +554,7 @@
return kUpdateNotAttempted;
}
const std::string& oat_file_name = *oat_.Filename();
+ const std::string& vdex_file_name = ReplaceFileExtension(oat_file_name, "vdex");
// dex2oat ignores missing dex files and doesn't report an error.
// Check explicitly here so we can detect the error properly.
@@ -574,8 +564,22 @@
return kUpdateNotAttempted;
}
- std::unique_ptr<File> oat_file;
- oat_file.reset(OS::CreateEmptyFile(oat_file_name.c_str()));
+ std::unique_ptr<File> vdex_file(OS::CreateEmptyFile(vdex_file_name.c_str()));
+ if (vdex_file.get() == nullptr) {
+ *error_msg = "Generation of oat file " + oat_file_name
+ + " not attempted because the vdex file " + vdex_file_name
+ + " could not be opened.";
+ return kUpdateNotAttempted;
+ }
+
+ if (fchmod(vdex_file->Fd(), 0644) != 0) {
+ *error_msg = "Generation of oat file " + oat_file_name
+ + " not attempted because the vdex file " + vdex_file_name
+ + " could not be made world readable.";
+ return kUpdateNotAttempted;
+ }
+
+ std::unique_ptr<File> oat_file(OS::CreateEmptyFile(oat_file_name.c_str()));
if (oat_file.get() == nullptr) {
*error_msg = "Generation of oat file " + oat_file_name
+ " not attempted because the oat file could not be created.";
@@ -591,17 +595,26 @@
std::vector<std::string> args;
args.push_back("--dex-file=" + dex_location_);
+ args.push_back("--vdex-fd=" + std::to_string(vdex_file->Fd()));
args.push_back("--oat-fd=" + std::to_string(oat_file->Fd()));
args.push_back("--oat-location=" + oat_file_name);
if (!Dex2Oat(args, error_msg)) {
- // Manually delete the file. This ensures there is no garbage left over if
- // the process unexpectedly died.
+ // Manually delete the oat and vdex files. This ensures there is no garbage
+ // left over if the process unexpectedly died.
+ vdex_file->Erase();
+ unlink(vdex_file_name.c_str());
oat_file->Erase();
unlink(oat_file_name.c_str());
return kUpdateFailed;
}
+ if (vdex_file->FlushCloseOrErase() != 0) {
+ *error_msg = "Unable to close vdex file " + vdex_file_name;
+ unlink(vdex_file_name.c_str());
+ return kUpdateFailed;
+ }
+
if (oat_file->FlushCloseOrErase() != 0) {
*error_msg = "Unable to close oat file " + oat_file_name;
unlink(oat_file_name.c_str());
@@ -830,7 +843,7 @@
std::unique_ptr<gc::space::ImageSpace> OatFileAssistant::OpenImageSpace(const OatFile* oat_file) {
DCHECK(oat_file != nullptr);
- std::string art_file = ArtFileName(oat_file);
+ std::string art_file = ReplaceFileExtension(oat_file->GetLocation(), "art");
if (art_file.empty()) {
return nullptr;
}