Implement the DDMS heap walking (for native and managed heaps).
This gets you the DDMS histograms of what's on your heaps.
Change-Id: I7133d044030b10a787277faf3a77e20c565e69c5
diff --git a/src/debugger.cc b/src/debugger.cc
index 3321d68..9f4bc4d 100644
--- a/src/debugger.cc
+++ b/src/debugger.cc
@@ -18,10 +18,18 @@
#include <sys/uio.h>
+#include "ScopedLocalRef.h"
#include "ScopedPrimitiveArray.h"
#include "stack_indirect_reference_table.h"
#include "thread_list.h"
+extern "C" void dlmalloc_walk_heap(void(*)(const void*, size_t, const void*, size_t, void*), void*);
+#ifndef HAVE_ANDROID_OS
+void dlmalloc_walk_heap(void(*)(const void*, size_t, const void*, size_t, void*), void*) {
+ // No-op for glibc.
+}
+#endif
+
namespace art {
class ObjectRegistry {
@@ -237,11 +245,11 @@
}
if (gDdmHpsgWhen != HPSG_WHEN_NEVER) {
LOG(DEBUG) << "Dumping VM heap to DDM";
- DdmSendHeapSegments(false, false);
+ DdmSendHeapSegments(false);
}
if (gDdmNhsgWhen != HPSG_WHEN_NEVER) {
LOG(DEBUG) << "Dumping native heap to DDM";
- DdmSendHeapSegments(false, true);
+ DdmSendHeapSegments(true);
}
}
@@ -675,18 +683,18 @@
static jfieldID type_fid = env->GetFieldID(Chunk_class, "type", "I");
// Create a byte[] corresponding to 'buf'.
- jbyteArray dataArray = env->NewByteArray(dataLen);
- if (dataArray == NULL) {
+ ScopedLocalRef<jbyteArray> dataArray(env, env->NewByteArray(dataLen));
+ if (dataArray.get() == NULL) {
LOG(WARNING) << "byte[] allocation failed: " << dataLen;
env->ExceptionClear();
return false;
}
- env->SetByteArrayRegion(dataArray, 0, dataLen, reinterpret_cast<const jbyte*>(buf));
+ env->SetByteArrayRegion(dataArray.get(), 0, dataLen, reinterpret_cast<const jbyte*>(buf));
const int kChunkHdrLen = 8;
// Run through and find all chunks. [Currently just find the first.]
- ScopedByteArrayRO contents(env, dataArray);
+ ScopedByteArrayRO contents(env, dataArray.get());
jint type = JDWP::Get4BE(reinterpret_cast<const uint8_t*>(&contents[0]));
jint length = JDWP::Get4BE(reinterpret_cast<const uint8_t*>(&contents[4]));
jint offset = kChunkHdrLen;
@@ -696,7 +704,7 @@
}
// Call "private static Chunk dispatch(int type, byte[] data, int offset, int length)".
- jobject chunk = env->CallStaticObjectMethod(DdmServer_class, dispatch_mid, type, dataArray, offset, length);
+ ScopedLocalRef<jobject> chunk(env, env->CallStaticObjectMethod(DdmServer_class, dispatch_mid, type, dataArray.get(), offset, length));
if (env->ExceptionCheck()) {
LOG(INFO) << StringPrintf("Exception thrown by dispatcher for 0x%08x", type);
env->ExceptionDescribe();
@@ -704,7 +712,7 @@
return false;
}
- if (chunk == NULL) {
+ if (chunk.get() == NULL) {
return false;
}
@@ -720,17 +728,17 @@
*
* So we're pretty much stuck with copying data around multiple times.
*/
- jbyteArray replyData = reinterpret_cast<jbyteArray>(env->GetObjectField(chunk, data_fid));
- length = env->GetIntField(chunk, length_fid);
- offset = env->GetIntField(chunk, offset_fid);
- type = env->GetIntField(chunk, type_fid);
+ ScopedLocalRef<jbyteArray> replyData(env, reinterpret_cast<jbyteArray>(env->GetObjectField(chunk.get(), data_fid)));
+ length = env->GetIntField(chunk.get(), length_fid);
+ offset = env->GetIntField(chunk.get(), offset_fid);
+ type = env->GetIntField(chunk.get(), type_fid);
- LOG(VERBOSE) << StringPrintf("DDM reply: type=0x%08x data=%p offset=%d length=%d", type, replyData, offset, length);
- if (length == 0 || replyData == NULL) {
+ LOG(VERBOSE) << StringPrintf("DDM reply: type=0x%08x data=%p offset=%d length=%d", type, replyData.get(), offset, length);
+ if (length == 0 || replyData.get() == NULL) {
return false;
}
- jsize replyLength = env->GetArrayLength(replyData);
+ jsize replyLength = env->GetArrayLength(replyData.get());
if (offset + length > replyLength) {
LOG(WARNING) << StringPrintf("chunk off=%d len=%d exceeds reply array len %d", offset, length, replyLength);
return false;
@@ -743,7 +751,7 @@
}
JDWP::Set4BE(reply + 0, type);
JDWP::Set4BE(reply + 4, length);
- env->GetByteArrayRegion(replyData, offset, length, reinterpret_cast<jbyte*>(reply + kChunkHdrLen));
+ env->GetByteArrayRegion(replyData.get(), offset, length, reinterpret_cast<jbyte*>(reply + kChunkHdrLen));
*pReplyBuf = reply;
*pReplyLen = length + kChunkHdrLen;
@@ -940,8 +948,222 @@
Dbg::DdmSendChunk(CHUNK_TYPE("HPIF"), bytes.size(), &bytes[0]);
}
-void Dbg::DdmSendHeapSegments(bool shouldLock, bool native) {
- UNIMPLEMENTED(WARNING) << "shouldLock=" << shouldLock << " native=" << native;
+enum HpsgSolidity {
+ SOLIDITY_FREE = 0,
+ SOLIDITY_HARD = 1,
+ SOLIDITY_SOFT = 2,
+ SOLIDITY_WEAK = 3,
+ SOLIDITY_PHANTOM = 4,
+ SOLIDITY_FINALIZABLE = 5,
+ SOLIDITY_SWEEP = 6,
+};
+
+enum HpsgKind {
+ KIND_OBJECT = 0,
+ KIND_CLASS_OBJECT = 1,
+ KIND_ARRAY_1 = 2,
+ KIND_ARRAY_2 = 3,
+ KIND_ARRAY_4 = 4,
+ KIND_ARRAY_8 = 5,
+ KIND_UNKNOWN = 6,
+ KIND_NATIVE = 7,
+};
+
+#define HPSG_PARTIAL (1<<7)
+#define HPSG_STATE(solidity, kind) ((uint8_t)((((kind) & 0x7) << 3) | ((solidity) & 0x7)))
+
+struct HeapChunkContext {
+ std::vector<uint8_t> buf;
+ uint8_t* p;
+ uint8_t* pieceLenField;
+ size_t totalAllocationUnits;
+ int type;
+ bool merge;
+ bool needHeader;
+
+ // Maximum chunk size. Obtain this from the formula:
+ // (((maximum_heap_size / ALLOCATION_UNIT_SIZE) + 255) / 256) * 2
+ HeapChunkContext(bool merge, bool native)
+ : buf(16384 - 16),
+ type(0),
+ merge(merge) {
+ Reset();
+ if (native) {
+ type = CHUNK_TYPE("NHSG");
+ } else {
+ type = merge ? CHUNK_TYPE("HPSG") : CHUNK_TYPE("HPSO");
+ }
+ }
+
+ ~HeapChunkContext() {
+ if (p > &buf[0]) {
+ Flush();
+ }
+ }
+
+ void EnsureHeader(const void* chunk_ptr) {
+ if (!needHeader) {
+ return;
+ }
+
+ // Start a new HPSx chunk.
+ JDWP::Write4BE(&p, 1); // Heap id (bogus; we only have one heap).
+ JDWP::Write1BE(&p, 8); // Size of allocation unit, in bytes.
+
+ JDWP::Write4BE(&p, reinterpret_cast<uintptr_t>(chunk_ptr)); // virtual address of segment start.
+ JDWP::Write4BE(&p, 0); // offset of this piece (relative to the virtual address).
+ // [u4]: length of piece, in allocation units
+ // We won't know this until we're done, so save the offset and stuff in a dummy value.
+ pieceLenField = p;
+ JDWP::Write4BE(&p, 0x55555555);
+ needHeader = false;
+ }
+
+ void Flush() {
+ // Patch the "length of piece" field.
+ CHECK_LE(&buf[0], pieceLenField);
+ CHECK_LE(pieceLenField, p);
+ JDWP::Set4BE(pieceLenField, totalAllocationUnits);
+
+ Dbg::DdmSendChunk(type, p - &buf[0], &buf[0]);
+ Reset();
+ }
+
+ private:
+ void Reset() {
+ p = &buf[0];
+ totalAllocationUnits = 0;
+ needHeader = true;
+ pieceLenField = NULL;
+ }
+
+ DISALLOW_COPY_AND_ASSIGN(HeapChunkContext);
+};
+
+#define ALLOCATION_UNIT_SIZE 8
+
+uint8_t ExamineObject(const Object* o, bool is_native_heap) {
+ if (o == NULL) {
+ return HPSG_STATE(SOLIDITY_FREE, 0);
+ }
+
+ // It's an allocated chunk. Figure out what it is.
+
+ // If we're looking at the native heap, we'll just return
+ // (SOLIDITY_HARD, KIND_NATIVE) for all allocated chunks.
+ if (is_native_heap || !Heap::IsLiveObjectLocked(o)) {
+ return HPSG_STATE(SOLIDITY_HARD, KIND_NATIVE);
+ }
+
+ Class* c = o->GetClass();
+ if (c == NULL) {
+ // The object was probably just created but hasn't been initialized yet.
+ return HPSG_STATE(SOLIDITY_HARD, KIND_OBJECT);
+ }
+
+ if (!Heap::IsHeapAddress(c)) {
+ LOG(WARNING) << "invalid class for managed heap object: " << o << " " << c;
+ return HPSG_STATE(SOLIDITY_HARD, KIND_UNKNOWN);
+ }
+
+ if (c->IsClassClass()) {
+ return HPSG_STATE(SOLIDITY_HARD, KIND_CLASS_OBJECT);
+ }
+
+ if (c->IsArrayClass()) {
+ if (o->IsObjectArray()) {
+ return HPSG_STATE(SOLIDITY_HARD, KIND_ARRAY_4);
+ }
+ switch (c->GetComponentSize()) {
+ case 1: return HPSG_STATE(SOLIDITY_HARD, KIND_ARRAY_1);
+ case 2: return HPSG_STATE(SOLIDITY_HARD, KIND_ARRAY_2);
+ case 4: return HPSG_STATE(SOLIDITY_HARD, KIND_ARRAY_4);
+ case 8: return HPSG_STATE(SOLIDITY_HARD, KIND_ARRAY_8);
+ }
+ }
+
+ return HPSG_STATE(SOLIDITY_HARD, KIND_OBJECT);
+}
+
+static void HeapChunkCallback(const void* chunk_ptr, size_t chunk_len, const void* user_ptr, size_t user_len, void* arg) {
+ HeapChunkContext* context = reinterpret_cast<HeapChunkContext*>(arg);
+
+ CHECK_EQ((chunk_len & (ALLOCATION_UNIT_SIZE-1)), 0U);
+
+ /* Make sure there's enough room left in the buffer.
+ * We need to use two bytes for every fractional 256
+ * allocation units used by the chunk.
+ */
+ {
+ size_t needed = (((chunk_len/ALLOCATION_UNIT_SIZE + 255) / 256) * 2);
+ size_t bytesLeft = context->buf.size() - (size_t)(context->p - &context->buf[0]);
+ if (bytesLeft < needed) {
+ context->Flush();
+ }
+
+ bytesLeft = context->buf.size() - (size_t)(context->p - &context->buf[0]);
+ if (bytesLeft < needed) {
+ LOG(WARNING) << "chunk is too big to transmit (chunk_len=" << chunk_len << ", " << needed << " bytes)";
+ return;
+ }
+ }
+
+ // OLD-TODO: notice when there's a gap and start a new heap, or at least a new range.
+ context->EnsureHeader(chunk_ptr);
+
+ // Determine the type of this chunk.
+ // OLD-TODO: if context.merge, see if this chunk is different from the last chunk.
+ // If it's the same, we should combine them.
+ uint8_t state = ExamineObject(reinterpret_cast<const Object*>(user_ptr), (context->type == CHUNK_TYPE("NHSG")));
+
+ // Write out the chunk description.
+ chunk_len /= ALLOCATION_UNIT_SIZE; // convert to allocation units
+ context->totalAllocationUnits += chunk_len;
+ while (chunk_len > 256) {
+ *context->p++ = state | HPSG_PARTIAL;
+ *context->p++ = 255; // length - 1
+ chunk_len -= 256;
+ }
+ *context->p++ = state;
+ *context->p++ = chunk_len - 1;
+}
+
+static void WalkHeap(bool merge, bool native) {
+ HeapChunkContext context(merge, native);
+ if (native) {
+ dlmalloc_walk_heap(HeapChunkCallback, &context);
+ } else {
+ Heap::WalkHeap(HeapChunkCallback, &context);
+ }
+}
+
+void Dbg::DdmSendHeapSegments(bool native) {
+ Dbg::HpsgWhen when;
+ Dbg::HpsgWhat what;
+ if (!native) {
+ when = gDdmHpsgWhen;
+ what = gDdmHpsgWhat;
+ } else {
+ when = gDdmNhsgWhen;
+ what = gDdmNhsgWhat;
+ }
+ if (when == HPSG_WHEN_NEVER) {
+ return;
+ }
+
+ // Figure out what kind of chunks we'll be sending.
+ CHECK(what == HPSG_WHAT_MERGED_OBJECTS || what == HPSG_WHAT_DISTINCT_OBJECTS) << static_cast<int>(what);
+
+ // First, send a heap start chunk.
+ uint8_t heap_id[4];
+ JDWP::Set4BE(&heap_id[0], 1); // Heap id (bogus; we only have one heap).
+ Dbg::DdmSendChunk(native ? CHUNK_TYPE("NHST") : CHUNK_TYPE("HPST"), sizeof(heap_id), heap_id);
+
+ // Send a series of heap segment chunks.
+ WalkHeap((what == HPSG_WHAT_MERGED_OBJECTS), native);
+
+ // Finally, send a heap end chunk.
+ Dbg::DdmSendChunk(native ? CHUNK_TYPE("NHEN") : CHUNK_TYPE("HPEN"), sizeof(heap_id), heap_id);
}
} // namespace art