ART: Don't attempt write flock if not zygote
When loading an image, don't attempt a RDWR flock if the process
is not the zygote. The lock will be rejected as the process does
not have permission to write the file.
Bug: 28011897
(cherry picked from commit fff377b13469b8c84ce55ee20b10ca80a5a0813d)
Change-Id: I567934c4e9a9a13e9131711240e9ecfdd58b69f7
diff --git a/runtime/gc/space/image_space.cc b/runtime/gc/space/image_space.cc
index 22bf5f9..a84b366 100644
--- a/runtime/gc/space/image_space.cc
+++ b/runtime/gc/space/image_space.cc
@@ -407,7 +407,7 @@
&is_global_cache);
}
- if (Runtime::Current()->IsZygote() && !secondary_image) {
+ if (is_zygote && !secondary_image) {
MarkZygoteStart(image_isa, Runtime::Current()->GetZygoteMaxFailedBoots());
}
@@ -444,7 +444,7 @@
// Whether we can write to the cache.
success = false;
} else if (secondary_image) {
- if (Runtime::Current()->IsZygote()) {
+ if (is_zygote) {
// Secondary image is out of date. Clear cache and exit to let it retry from scratch.
LOG(ERROR) << "Cannot patch secondary image '" << image_location
<< "', clearing dalvik_cache and restarting zygote.";
@@ -503,7 +503,16 @@
// descriptor (and the associated exclusive lock) to be released when
// we leave Create.
ScopedFlock image_lock;
- image_lock.Init(image_filename->c_str(), error_msg);
+ // Should this be a RDWR lock? This is only a defensive measure, as at
+ // this point the image should exist.
+ // However, only the zygote can write into the global dalvik-cache, so
+ // restrict to zygote processes, or any process that isn't using
+ // /data/dalvik-cache (which we assume to be allowed to write there).
+ const bool rw_lock = is_zygote || !is_global_cache;
+ image_lock.Init(image_filename->c_str(),
+ rw_lock ? (O_CREAT | O_RDWR) : O_RDONLY /* flags */,
+ true /* block */,
+ error_msg);
VLOG(startup) << "Using image file " << image_filename->c_str() << " for image location "
<< image_location;
// If we are in /system we can assume the image is good. We can also
