Added an allocated memory cache to avoid having to allocate memory over and
over when running JITed expressions. The allocated memory cache will cache
allocate memory a page at a time for each permission combination and divvy up
the memory and hand it out in 16 byte increments.
git-svn-id: https://llvm.org/svn/llvm-project/llvdb/trunk@131453 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Target/Memory.cpp b/source/Target/Memory.cpp
new file mode 100644
index 0000000..3f5567b
--- /dev/null
+++ b/source/Target/Memory.cpp
@@ -0,0 +1,413 @@
+//===-- Memory.cpp ----------------------------------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Target/Memory.h"
+// C Includes
+// C++ Includes
+// Other libraries and framework includes
+// Project includes
+#include "lldb/Core/DataBufferHeap.h"
+#include "lldb/Core/State.h"
+#include "lldb/Core/Log.h"
+#include "lldb/Target/Process.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+//----------------------------------------------------------------------
+// MemoryCache constructor
+//----------------------------------------------------------------------
+MemoryCache::MemoryCache(Process &process) :
+ m_process (process),
+ m_cache_line_byte_size (512),
+ m_cache_mutex (Mutex::eMutexTypeRecursive),
+ m_cache ()
+{
+}
+
+//----------------------------------------------------------------------
+// Destructor
+//----------------------------------------------------------------------
+MemoryCache::~MemoryCache()
+{
+}
+
+void
+MemoryCache::Clear()
+{
+ Mutex::Locker locker (m_cache_mutex);
+ m_cache.clear();
+}
+
+void
+MemoryCache::Flush (addr_t addr, size_t size)
+{
+ if (size == 0)
+ return;
+
+ const uint32_t cache_line_byte_size = m_cache_line_byte_size;
+ const addr_t end_addr = (addr + size - 1);
+ const addr_t flush_start_addr = addr - (addr % cache_line_byte_size);
+ const addr_t flush_end_addr = end_addr - (end_addr % cache_line_byte_size);
+
+ Mutex::Locker locker (m_cache_mutex);
+ if (m_cache.empty())
+ return;
+
+ assert ((flush_start_addr % cache_line_byte_size) == 0);
+
+ for (addr_t curr_addr = flush_start_addr; curr_addr <= flush_end_addr; curr_addr += cache_line_byte_size)
+ {
+ collection::iterator pos = m_cache.find (curr_addr);
+ if (pos != m_cache.end())
+ m_cache.erase(pos);
+ }
+}
+
+size_t
+MemoryCache::Read (addr_t addr,
+ void *dst,
+ size_t dst_len,
+ Error &error)
+{
+ size_t bytes_left = dst_len;
+ if (dst && bytes_left > 0)
+ {
+ const uint32_t cache_line_byte_size = m_cache_line_byte_size;
+ uint8_t *dst_buf = (uint8_t *)dst;
+ addr_t curr_addr = addr - (addr % cache_line_byte_size);
+ addr_t cache_offset = addr - curr_addr;
+ Mutex::Locker locker (m_cache_mutex);
+
+ while (bytes_left > 0)
+ {
+ collection::const_iterator pos = m_cache.find (curr_addr);
+ collection::const_iterator end = m_cache.end ();
+
+ if (pos != end)
+ {
+ size_t curr_read_size = cache_line_byte_size - cache_offset;
+ if (curr_read_size > bytes_left)
+ curr_read_size = bytes_left;
+
+ memcpy (dst_buf + dst_len - bytes_left, pos->second->GetBytes() + cache_offset, curr_read_size);
+
+ bytes_left -= curr_read_size;
+ curr_addr += curr_read_size + cache_offset;
+ cache_offset = 0;
+
+ if (bytes_left > 0)
+ {
+ // Get sequential cache page hits
+ for (++pos; (pos != end) && (bytes_left > 0); ++pos)
+ {
+ assert ((curr_addr % cache_line_byte_size) == 0);
+
+ if (pos->first != curr_addr)
+ break;
+
+ curr_read_size = pos->second->GetByteSize();
+ if (curr_read_size > bytes_left)
+ curr_read_size = bytes_left;
+
+ memcpy (dst_buf + dst_len - bytes_left, pos->second->GetBytes(), curr_read_size);
+
+ bytes_left -= curr_read_size;
+ curr_addr += curr_read_size;
+
+ // We have a cache page that succeeded to read some bytes
+ // but not an entire page. If this happens, we must cap
+ // off how much data we are able to read...
+ if (pos->second->GetByteSize() != cache_line_byte_size)
+ return dst_len - bytes_left;
+ }
+ }
+ }
+
+ // We need to read from the process
+
+ if (bytes_left > 0)
+ {
+ assert ((curr_addr % cache_line_byte_size) == 0);
+ std::auto_ptr<DataBufferHeap> data_buffer_heap_ap(new DataBufferHeap (cache_line_byte_size, 0));
+ size_t process_bytes_read = m_process.ReadMemoryFromInferior (curr_addr,
+ data_buffer_heap_ap->GetBytes(),
+ data_buffer_heap_ap->GetByteSize(),
+ error);
+ if (process_bytes_read == 0)
+ return dst_len - bytes_left;
+
+ if (process_bytes_read != cache_line_byte_size)
+ data_buffer_heap_ap->SetByteSize (process_bytes_read);
+ m_cache[curr_addr] = DataBufferSP (data_buffer_heap_ap.release());
+ // We have read data and put it into the cache, continue through the
+ // loop again to get the data out of the cache...
+ }
+ }
+ }
+
+ return dst_len - bytes_left;
+}
+
+
+
+AllocatedBlock::AllocatedBlock (lldb::addr_t addr,
+ uint32_t byte_size,
+ uint32_t permissions,
+ uint32_t chunk_size) :
+ m_addr (addr),
+ m_byte_size (byte_size),
+ m_permissions (permissions),
+ m_chunk_size (chunk_size),
+ m_offset_to_chunk_size ()
+// m_allocated (byte_size / chunk_size)
+{
+ assert (byte_size > chunk_size);
+}
+
+AllocatedBlock::~AllocatedBlock ()
+{
+}
+
+lldb::addr_t
+AllocatedBlock::ReserveBlock (uint32_t size)
+{
+ addr_t addr = LLDB_INVALID_ADDRESS;
+ if (size <= m_byte_size)
+ {
+ const uint32_t needed_chunks = CalculateChunksNeededForSize (size);
+ LogSP log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS | LIBLLDB_LOG_VERBOSE));
+
+ if (m_offset_to_chunk_size.empty())
+ {
+ m_offset_to_chunk_size[0] = needed_chunks;
+ if (log)
+ log->Printf ("[1] AllocatedBlock::ReserveBlock (size = %u (0x%x)) => offset = 0x%x, %u %u bit chunks", size, size, 0, needed_chunks, m_chunk_size);
+ addr = m_addr;
+ }
+ else
+ {
+ uint32_t last_offset = 0;
+ OffsetToChunkSize::const_iterator pos = m_offset_to_chunk_size.begin();
+ OffsetToChunkSize::const_iterator end = m_offset_to_chunk_size.end();
+ while (pos != end)
+ {
+ if (pos->first > last_offset)
+ {
+ const uint32_t bytes_available = pos->first - last_offset;
+ const uint32_t num_chunks = CalculateChunksNeededForSize (bytes_available);
+ if (num_chunks >= needed_chunks)
+ {
+ m_offset_to_chunk_size[last_offset] = needed_chunks;
+ if (log)
+ log->Printf ("[2] AllocatedBlock::ReserveBlock (size = %u (0x%x)) => offset = 0x%x, %u %u bit chunks", size, size, last_offset, needed_chunks, m_chunk_size);
+ addr = m_addr + last_offset;
+ break;
+ }
+ }
+
+ last_offset = pos->first + pos->second * m_chunk_size;
+
+ if (++pos == end)
+ {
+ // Last entry...
+ const uint32_t chunks_left = CalculateChunksNeededForSize (m_byte_size - last_offset);
+ if (chunks_left >= needed_chunks)
+ {
+ m_offset_to_chunk_size[last_offset] = needed_chunks;
+ if (log)
+ log->Printf ("[3] AllocatedBlock::ReserveBlock (size = %u (0x%x)) => offset = 0x%x, %u %u bit chunks", size, size, last_offset, needed_chunks, m_chunk_size);
+ addr = m_addr + last_offset;
+ break;
+ }
+ }
+ }
+ }
+// const uint32_t total_chunks = m_allocated.size ();
+// uint32_t unallocated_idx = 0;
+// uint32_t allocated_idx = m_allocated.find_first();
+// uint32_t first_chunk_idx = UINT32_MAX;
+// uint32_t num_chunks;
+// while (1)
+// {
+// if (allocated_idx == UINT32_MAX)
+// {
+// // No more bits are set starting from unallocated_idx, so we
+// // either have enough chunks for the request, or we don't.
+// // Eiter way we break out of the while loop...
+// num_chunks = total_chunks - unallocated_idx;
+// if (needed_chunks <= num_chunks)
+// first_chunk_idx = unallocated_idx;
+// break;
+// }
+// else if (allocated_idx > unallocated_idx)
+// {
+// // We have some allocated chunks, check if there are enough
+// // free chunks to satisfy the request?
+// num_chunks = allocated_idx - unallocated_idx;
+// if (needed_chunks <= num_chunks)
+// {
+// // Yep, we have enough!
+// first_chunk_idx = unallocated_idx;
+// break;
+// }
+// }
+//
+// while (unallocated_idx < total_chunks)
+// {
+// if (m_allocated[unallocated_idx])
+// ++unallocated_idx;
+// else
+// break;
+// }
+//
+// if (unallocated_idx >= total_chunks)
+// break;
+//
+// allocated_idx = m_allocated.find_next(unallocated_idx);
+// }
+//
+// if (first_chunk_idx != UINT32_MAX)
+// {
+// const uint32_t end_bit_idx = unallocated_idx + needed_chunks;
+// for (uint32_t idx = first_chunk_idx; idx < end_bit_idx; ++idx)
+// m_allocated.set(idx);
+// return m_addr + m_chunk_size * first_chunk_idx;
+// }
+ }
+ LogSP log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS | LIBLLDB_LOG_VERBOSE));
+ if (log)
+ log->Printf ("AllocatedBlock::ReserveBlock (size = %u (0x%x)) => 0x%16.16llx", size, size, (uint64_t)addr);
+ return addr;
+}
+
+bool
+AllocatedBlock::FreeBlock (addr_t addr)
+{
+ uint32_t offset = addr - m_addr;
+ OffsetToChunkSize::iterator pos = m_offset_to_chunk_size.find (offset);
+ bool success = false;
+ if (pos != m_offset_to_chunk_size.end())
+ {
+ m_offset_to_chunk_size.erase (pos);
+ success = true;
+ }
+ LogSP log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS | LIBLLDB_LOG_VERBOSE));
+ if (log)
+ log->Printf ("AllocatedBlock::FreeBlock (addr = 0x%16.16llx) => %i", (uint64_t)addr, success);
+ return success;
+}
+
+
+AllocatedMemoryCache::AllocatedMemoryCache (Process &process) :
+ m_process (process),
+ m_mutex (Mutex::eMutexTypeRecursive),
+ m_memory_map()
+{
+}
+
+AllocatedMemoryCache::~AllocatedMemoryCache ()
+{
+}
+
+
+void
+AllocatedMemoryCache::Clear()
+{
+ Mutex::Locker locker (m_mutex);
+ if (m_process.IsAlive())
+ {
+ PermissionsToBlockMap::iterator pos, end = m_memory_map.end();
+ for (pos = m_memory_map.begin(); pos != end; ++pos)
+ m_process.DoDeallocateMemory(pos->second->GetBaseAddress());
+ }
+ m_memory_map.clear();
+}
+
+
+AllocatedMemoryCache::AllocatedBlockSP
+AllocatedMemoryCache::AllocatePage (uint32_t byte_size,
+ uint32_t permissions,
+ uint32_t chunk_size,
+ Error &error)
+{
+ AllocatedBlockSP block_sp;
+ const size_t page_size = 4096;
+ const size_t num_pages = (byte_size + page_size - 1) / page_size;
+ const size_t page_byte_size = num_pages * page_size;
+
+ addr_t addr = m_process.DoAllocateMemory(page_byte_size, permissions, error);
+
+ LogSP log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
+ if (log)
+ {
+ log->Printf ("Process::DoAllocateMemory (byte_size = 0x%8.8zx, permissions = %s) => 0x%16.16llx",
+ page_byte_size,
+ GetPermissionsAsCString(permissions),
+ (uint64_t)addr);
+ }
+
+ if (addr != LLDB_INVALID_ADDRESS)
+ {
+ block_sp.reset (new AllocatedBlock (addr, page_byte_size, permissions, chunk_size));
+ m_memory_map.insert (std::make_pair (permissions, block_sp));
+ }
+ return block_sp;
+}
+
+lldb::addr_t
+AllocatedMemoryCache::AllocateMemory (size_t byte_size,
+ uint32_t permissions,
+ Error &error)
+{
+ Mutex::Locker locker (m_mutex);
+
+ addr_t addr = LLDB_INVALID_ADDRESS;
+ std::pair<PermissionsToBlockMap::iterator, PermissionsToBlockMap::iterator> range = m_memory_map.equal_range (permissions);
+
+ for (PermissionsToBlockMap::iterator pos = range.first; pos != range.second; ++pos)
+ {
+ addr = (*pos).second->ReserveBlock (byte_size);
+ }
+
+ if (addr == LLDB_INVALID_ADDRESS)
+ {
+ AllocatedBlockSP block_sp (AllocatePage (byte_size, permissions, 16, error));
+
+ if (block_sp)
+ addr = block_sp->ReserveBlock (byte_size);
+ }
+ LogSP log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
+ if (log)
+ log->Printf ("AllocatedMemoryCache::AllocateMemory (byte_size = 0x%8.8zx, permissions = %s) => 0x%16.16llx", byte_size, GetPermissionsAsCString(permissions), (uint64_t)addr);
+ return addr;
+}
+
+bool
+AllocatedMemoryCache::DeallocateMemory (lldb::addr_t addr)
+{
+ Mutex::Locker locker (m_mutex);
+
+ PermissionsToBlockMap::iterator pos, end = m_memory_map.end();
+ bool success = false;
+ for (pos = m_memory_map.begin(); pos != end; ++pos)
+ {
+ if (pos->second->Contains (addr))
+ {
+ success = pos->second->FreeBlock (addr);
+ break;
+ }
+ }
+ LogSP log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
+ if (log)
+ log->Printf("AllocatedMemoryCache::DeallocateMemory (addr = 0x%16.16llx) => %i", (uint64_t)addr, success);
+ return success;
+}
+
+