History log of /art/runtime/gc_root.h
Revision Date Author Comments
0d5a281c671444bfa75d63caf1427a8c0e6e1177 13-Nov-2015 Roland Levillain <rpl@google.com> x86/x86-64 read barrier support for concurrent GC in Optimizing.

This first implementation uses slow paths to instrument heap
reference loads and GC root loads for the concurrent copying
collector, respectively calling the artReadBarrierSlow and
artReadBarrierForRootSlow (new) runtime entry points.

Notes:
- This implementation does not instrument HInvokeVirtual
nor HInvokeInterface instructions (for class reference
loads), as the corresponding read barriers are not stricly
required with the current concurrent copying collector.
- Intrinsics which may eventually call (on slow path) are
disabled when read barriers are enabled, as the current
slow path infrastructure does not support this case.
- When read barriers are enabled, the code generated for a
HArraySet instruction always go into the array set slow
path for object arrays (delegating the operation to the
runtime), as we are lacking a mechanism to keep a
temporary register live accross a runtime call (needed for
the instrumentation of type checking code, which requires
two successive read barriers).

Bug: 12687968
Change-Id: I14cd6107233c326389120336f93955b28ffbb329
9b1c71ec77d92d63f1c2183b0cd3588727b2c265 03-Sep-2015 Mathieu Chartier <mathieuc@google.com> Make class loaders weak roots

Making the class loaders weak roots in the class linker prevents them
from keeping the classes as live. However we currently do mark them
as strong roots to make sure no accidental class unloading occurs
until the logic to free from linear alloc is complete.

Bug: 22720414

Change-Id: I57466236d9ce6fd064dda9a30ce8ab68094fb8b0
90443477f9a0061581c420775ce3b7eeae7468bc 17-Jul-2015 Mathieu Chartier <mathieuc@google.com> Move to newer clang annotations

Also enable -Wthread-safety-negative.

Changes:
Switch to capabilities and negative capabilities.

Future work:
Use capabilities to implement uninterruptible annotations to work
with AssertNoThreadSuspension.

Bug: 20072211

Change-Id: I42fcbe0300d98a831c89d1eff3ecd5a7e99ebf33
1ed11b9ad5512cf464cb1686640df53201fa5297 12-Jun-2015 Man Cao <manc@google.com> Restore DDMS recent allocation tracking's behavior

Make the allocation tracker mark recently allocated objects as roots,
so the allocation records are not swept. Because DDMS needs recent
allocation tracking records even for dead objects. This should fix
the flaky failures for 098-ddmc test, but it cannot pass GC stress
test (OOM). Re-enabled 098-ddmc for other tests.

There should be an option to not mark them as roots, when user only
needs HPROF dump with traces but not DDMS's recent allocation tracking.
Probably need to add a new JNI API function for this option.

There could be another way to keep a second list of recent allocation
records and maintain a type cache for them, so not to make the objects
roots. But it's more complex, and not sure which is better.

Also reduce memory usage for AllocRecordStackTrace objects, and change
default stack depth to 16. Rename the property that controls the stack
depth to "debug.allocTracker.maxStackDepth" so developer can change it.

Bug:20037135
Change-Id: Ic6b9ae87bdcda558be6f14ded8057e763439881c
3f64f25151780fdea3511be62b4fe50775f86541 13-Jun-2015 Hiroshi Yamauchi <yamauchi@google.com> Print more diagnosis info on to-space invariant violation.

Pass the method/field (in GcRootSource) to the read barrier to print
more info when a to-space invariant violation is detected on a
method/field GC root access.

Refactor ConcurrentCopying::AssertToSpaceInvariant().

Bug: 12687968
Bug: 21564728

Change-Id: I3a5fde1f41969349b0fee6cd9217b948d5241a7c
9086b65b2ad35dd39a8afc62d535be8217208d08 14-Apr-2015 Mathieu Chartier <mathieuc@google.com> Fix valgrind tests

Delete large objects in space destructor. Also some cleanup.

Change-Id: I4c4e90149841a156b7a3236201b37683e14890fb
d3ed9a320a89cb9b91b2361892c043ab7e112717 10-Apr-2015 Mathieu Chartier <mathieuc@google.com> Fix DCHECK failures from Class::VisitFieldRoots

We now use GetDeclaringClassUnchecked when marking roots to fix
flaky test failures. Fixed a race condition in root marking where
we could have non zero field array length with a null pointer.
Fixed a race condition where we could be marking roots before
FixupTemporaryDeclaringClass had finished. The solution is to
only do the declaring class CHECK if we are at least resolved.
Fixed JDWP tests by changing FieldId / MethodId to be 64 bits.

Also some cleanup.

Change-Id: Ibac09519860d93c3f68a5cc964bbc91dc10a279a
4809d0a8a5fca85a67dd0588ead5dfbd0f1acf96 07-Apr-2015 Mathieu Chartier <mathieuc@google.com> Fix CC root visiting bug

Also some cleanup.

Change-Id: Ia3de8f2d409770be3619ec116e8b06ecd82338fe
758a801b66c134361a7b43f7e83f85d1fb800c4c 04-Apr-2015 Andreas Gampe <agampe@google.com> ART: Enable Clang's -Wdeprecated

Replace throw() with noexcept.

Add default copy constructors and copy assignment constructors for
cases with destructors, as the implicit definition is deprecated.

Change-Id: Ice306a3f510b072b00bec4d4360f7c8055135c9d
bb87e0f1a52de656bc77cb01cb887e51a0e5198b 03-Apr-2015 Mathieu Chartier <mathieuc@google.com> Refactor and improve GC root handling

Changed GcRoot to use compressed references. Changed root visiting to
use virtual functions instead of function pointers. Changed root visting
interface to be an array of roots instead of a single root at a time.
Added buffered root marking helper to avoid dispatch overhead.

Root marking seems a bit faster on EvaluateAndApplyChanges due to batch
marking. Pause times unaffected.

Mips64 is untested but might work, maybe.

Before:
MarkConcurrentRoots: Sum: 67.678ms 99% C.I. 2us-664.999us Avg: 161.138us Max: 671us

After:
MarkConcurrentRoots: Sum: 54.806ms 99% C.I. 2us-499.986us Avg: 136.333us Max: 602us

Bug: 19264997

Change-Id: I0a71ebb5928f205b9b3f7945b25db6489d5657ca
9e47bfa71d42df101aff9d156a1b296eaf6566a2 23-Feb-2015 Hiroshi Yamauchi <yamauchi@google.com> Avoid unaligned accesses (SIGBUG/BUS_ADRALN) in IRT.

Pointers in IrtEntry aren't currently aligned under 64 bit builds. But
unaligned atomic stores (store exclusive) do not work on arm64 (causes
SIGBUG/BUS_ADRALN). Fix CC collector crashes caused by this.

Bug: 12687968
Change-Id: I1d2f5376778a9a1e5cfea876f1f57d7a88ad5445
e34fa1df67fbe0173b4ea9abddcc3ae3d0537037 14-Jan-2015 Mathieu Chartier <mathieuc@google.com> Print more info in MarkSweep::VerifyRoot

Refactored old root callback to use a new class called RootInfo.
RootInfo contains all the relevant info related to the root
associated with the callback. The MarkSweep::VerifyRoot function
now uses this info to print the StackVisitor's described location
if the GC root is of the type kRootJavaFrame.

Some other cleanup.

Example output:
E/art (12167): Tried to mark 0x123 not contained by any spaces
E/art (12167): Attempting see if it's a bad root
E/art (12167): Found invalid root: 0x123 with type RootJavaFrame
E/art (12167): Location=Visiting method
'void java.lang.Runtime.gc()' at dex PC 0xffffffff (native PC 0x0)
vreg=0

(cherry picked from commit 12f7423a2bb4bfab76700d84eb6d4338d211983a)

Bug: 18588862
Change-Id: Ic5a2781f704e931265ffb3621c2eab4b2e25f60f
12f7423a2bb4bfab76700d84eb6d4338d211983a 14-Jan-2015 Mathieu Chartier <mathieuc@google.com> Print more info in MarkSweep::VerifyRoot

Refactored old root callback to use a new class called RootInfo.
RootInfo contains all the relevant info related to the root
associated with the callback. The MarkSweep::VerifyRoot function
now uses this info to print the StackVisitor's described location
if the GC root is of the type kRootJavaFrame.

Some other cleanup.

Example output:
E/art (12167): Tried to mark 0x123 not contained by any spaces
E/art (12167): Attempting see if it's a bad root
E/art (12167): Found invalid root: 0x123 with type RootJavaFrame
E/art (12167): Location=Visiting method
'void java.lang.Runtime.gc()' at dex PC 0xffffffff (native PC 0x0)
vreg=0

Bug: 18588862
Change-Id: Ic5a2781f704e931265ffb3621c2eab4b2e25f60f
c2e20629c7dfdb0f679fa30c14b41fe68588697f 03-Nov-2014 Mathieu Chartier <mathieuc@google.com> Add hash set

More memory efficient than libcxx since we do not box the values.

Change intern table to use new hash set. Clean up intern table by
removing const casts and deleting unnecessary code.

Changed the class linker to use a hash set, also added a pre-zygote
class table.

5 samples of:
adb shell stop && adb shell start && sleep 60 && adb shell dumpsys meminfo
Before:
165929 kB: Native
175859 kB: Native
168434 kB: Native
166559 kB: Native
169958 kB: Native

After:
160972 kB: Native
159439 kB: Native
157204 kB: Native
165093 kB: Native
163039 kB: Native

TODO: Add HashTable which is implemented by using a HashSet.
TODO: Use for DexFile::find_class_def_misses_.
TODO: Investigate using mem maps instead of native heap.

Bug: 17808975

Change-Id: I93e376cf6eb9628cf52f4aefdadb6157acfb799a

(cherry picked from commit e05d1d5fd86867afc7513b1c546375dba11eee50)
e05d1d5fd86867afc7513b1c546375dba11eee50 03-Nov-2014 Mathieu Chartier <mathieuc@google.com> Add hash set

More memory efficient than libcxx since we do not box the values.

Change intern table to use new hash set. Clean up intern table by
removing const casts and deleting unnecessary code.

Changed the class linker to use a hash set, also added a pre-zygote
class table.

5 samples of:
adb shell stop && adb shell start && sleep 60 && adb shell dumpsys meminfo
Before:
165929 kB: Native
175859 kB: Native
168434 kB: Native
166559 kB: Native
169958 kB: Native

After:
160972 kB: Native
159439 kB: Native
157204 kB: Native
165093 kB: Native
163039 kB: Native

TODO: Add HashTable which is implemented by using a HashSet.
TODO: Use for DexFile::find_class_def_misses_.
TODO: Investigate using mem maps instead of native heap.

Bug: 17808975

Change-Id: I93e376cf6eb9628cf52f4aefdadb6157acfb799a
eb175f70ef352ce0b9bcafdf06c5ac22b0ff626a 31-Oct-2014 Mathieu Chartier <mathieuc@google.com> Add image strings to intern table

When we create the runtime, we now add the image strings to the
intern table if we are the zygote. This caused some memory bloat,
so I added an extra unordered set to the intern table.

There is now two unordered sets (hash talbe). One for pre-zygote
interns and one for post-zygote interns. This helps since the
pre-zygote hash table doesn't get dirtied. Even with adding
the image strings, we get total memory savings of around 5-7 MB
native PSS after device boot.

FB launch Before:
2.20% art::DexFile::FindStringId(char const*) const
TotalTime: 2069
TotalTime: 1985
TotalTime: 2088
TotalTime: 2003
TotalTime: 2034
TotalTime: 2049
After boot native PSS: 175585 kB: Native

After:
0.27% art::DexFile::FindStringId(char const*) const
TotalTime: 1682
TotalTime: 1756
TotalTime: 1825
TotalTime: 1751
TotalTime: 1666
TotalTime: 1813
After boot native PSS: 167089 kB: Native

Bug: 18054905
Bug: 16828525
Bug: 17808975

(cherry picked from commit b6e292bf7eac9d73c6b79b1e9b7b87beb02436c9)

Change-Id: Ie367f3222f8c4db409ec49c3845276908b51e9c9
b6e292bf7eac9d73c6b79b1e9b7b87beb02436c9 31-Oct-2014 Mathieu Chartier <mathieuc@google.com> Add image strings to intern table

When we create the runtime, we now add the image strings to the
intern table if we are the zygote. This caused some memory bloat,
so I added an extra unordered set to the intern table.

There is now two unordered sets (hash talbe). One for pre-zygote
interns and one for post-zygote interns. This helps since the
pre-zygote hash table doesn't get dirtied. Even with adding
the image strings, we get total memory savings of around 5-7 MB
native PSS after device boot.

FB launch Before:
2.20% art::DexFile::FindStringId(char const*) const
TotalTime: 2069
TotalTime: 1985
TotalTime: 2088
TotalTime: 2003
TotalTime: 2034
TotalTime: 2049
After boot native PSS: 175585 kB: Native

After:
0.27% art::DexFile::FindStringId(char const*) const
TotalTime: 1682
TotalTime: 1756
TotalTime: 1825
TotalTime: 1751
TotalTime: 1666
TotalTime: 1813
After boot native PSS: 167089 kB: Native

Bug: 18054905
Bug: 16828525
Bug: 17808975

Change-Id: Ie367f3222f8c4db409ec49c3845276908b51e9c9
ba17fb00004077534a53ba30327a740d1279d9b5 03-Sep-2014 Mathieu Chartier <mathieuc@google.com> Add missing read barriers to intern table.

Also deleted GcRoot::Assign.

(cherry picked from commit c2bda539093db61be1f4095e579f6e68db8a23f1)

(cherry picked from commit 0ba1fed9978ba2fbfe129fe62095c983e8a5391b)

Change-Id: I7158774c6a30de7e569ee7afd978fa27f667fac2
0ba1fed9978ba2fbfe129fe62095c983e8a5391b 03-Sep-2014 Mathieu Chartier <mathieuc@google.com> Add missing read barriers to intern table.

Also deleted GcRoot::Assign.

(cherry picked from commit c2bda539093db61be1f4095e579f6e68db8a23f1)

Change-Id: Id286020e47d19862ec43dc1908b5e9d85b76c279
c2bda539093db61be1f4095e579f6e68db8a23f1 03-Sep-2014 Mathieu Chartier <mathieuc@google.com> Add missing read barriers to intern table.

Also deleted GcRoot::Assign.

Change-Id: Ib1ea739cf79c72fc92a8628cd9095c11b660e018
cdfd39f579574a75b98e7ad48c69826b00361b27 30-Aug-2014 Mathieu Chartier <mathieuc@google.com> Change intern table to unordered set.

Intern table active used bytes goes from 430k to 317k on system
server. Similar %wise savings on other apps.

Bug: 16238192

(cherry picked from commit d910fcef539e12ab181e56ec80684f39c4e95733)

Change-Id: Ic70395124435c6f420a77e6d8639404a160f395a
d910fcef539e12ab181e56ec80684f39c4e95733 30-Aug-2014 Mathieu Chartier <mathieuc@google.com> Change intern table to unordered set.

Intern table active used bytes goes from 430k to 317k on system
server. Similar %wise savings on other apps.

Bug: 16238192

Change-Id: I92de72de3eae0b76629e9da83db2c2d0fa613052
bad0267eaab9d6a522d05469ff90501deefdb88b 25-Aug-2014 Mathieu Chartier <mathieuc@google.com> Add native memory accounting through custom allocator.

Added a custom allocator that lets you pass in a special tag which
specifices where the allocation came from. This is used when
dumping. The performance overhead is low since each allocation only
does a atomic add/sub for each allocation/free.

The measurements are dumped to traces.txt during SIGQUIT.

Example output:
I/art (27274): AllocatorTagHeap active=120 max=120 total=168
I/art (27274): AllocatorTagMonitorList active=1572 max=6240 total=11724
I/art (27274): AllocatorTagClassTable active=185208 max=185208 total=268608
I/art (27274): AllocatorTagInternTable active=430368 max=430368 total=436080
I/art (27274): AllocatorTagMaps active=5616 max=6168 total=34392
I/art (27274): AllocatorTagLOS active=1024 max=1536 total=2044
I/art (27274): AllocatorTagSafeMap active=0 max=51936 total=533688
I/art (27274): AllocatorTagLOSMaps active=144 max=1248 total=5760
I/art (27274): AllocatorTagReferenceTable active=10944 max=11840 total=19136
I/art (27274): AllocatorTagHeapBitmap active=32 max=40 total=56
I/art (27274): AllocatorTagHeapBitmapLOS active=8 max=8 total=8
I/art (27274): AllocatorTagVerifier active=0 max=18844 total=1073156
I/art (27274): AllocatorTagModUnionCardSet active=5300 max=5920 total=56020
I/art (27274): AllocatorTagModUnionReferenceArray active=24864 max=24864 total=24864
I/art (27274): AllocatorTagJNILibrarires active=320 max=320 total=320
I/art (27274): AllocatorTagOatFile active=1400 max=1400 total=5852

Change-Id: Ibb470ef2e9c9a24563bb46422d46a55799704d82

(cherry picked from commit 5369c40f75fdcb1be7a7c06db212ce965c83a164)
5369c40f75fdcb1be7a7c06db212ce965c83a164 25-Aug-2014 Mathieu Chartier <mathieuc@google.com> Add native memory accounting through custom allocator.

Added a custom allocator that lets you pass in a special tag which
specifices where the allocation came from. This is used when
dumping. The performance overhead is low since each allocation only
does a atomic add/sub for each allocation/free.

The measurements are dumped to traces.txt during SIGQUIT.

Example output:
I/art (27274): AllocatorTagHeap active=120 max=120 total=168
I/art (27274): AllocatorTagMonitorList active=1572 max=6240 total=11724
I/art (27274): AllocatorTagClassTable active=185208 max=185208 total=268608
I/art (27274): AllocatorTagInternTable active=430368 max=430368 total=436080
I/art (27274): AllocatorTagMaps active=5616 max=6168 total=34392
I/art (27274): AllocatorTagLOS active=1024 max=1536 total=2044
I/art (27274): AllocatorTagSafeMap active=0 max=51936 total=533688
I/art (27274): AllocatorTagLOSMaps active=144 max=1248 total=5760
I/art (27274): AllocatorTagReferenceTable active=10944 max=11840 total=19136
I/art (27274): AllocatorTagHeapBitmap active=32 max=40 total=56
I/art (27274): AllocatorTagHeapBitmapLOS active=8 max=8 total=8
I/art (27274): AllocatorTagVerifier active=0 max=18844 total=1073156
I/art (27274): AllocatorTagModUnionCardSet active=5300 max=5920 total=56020
I/art (27274): AllocatorTagModUnionReferenceArray active=24864 max=24864 total=24864
I/art (27274): AllocatorTagJNILibrarires active=320 max=320 total=320
I/art (27274): AllocatorTagOatFile active=1400 max=1400 total=5852

Bug: 16238192

Change-Id: Ibb470ef2e9c9a24563bb46422d46a55799704d82
94f7b49578b6aaa80de8ffed230648d601393905 23-Jul-2014 Hiroshi Yamauchi <yamauchi@google.com> Add GcRoot to clean up and enforce read barriers.

Introduce a value-type wrapper around Object* for GC roots so that 1)
we won't have to directly add the read barrier code in many places and
2) we can avoid accidentally bypassing/missing read barriers on GC
roots (the GcRoot interface ensures that the read barrier is executed
on a read).

The jdwp test passed.

Bug: 12687968
Change-Id: Ib167c7c325b3c7e3900133578815f04d219972a1