1 //===-- Memory.cpp ----------------------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "lldb/Target/Memory.h" 11 // C Includes 12 #include <inttypes.h> 13 // C++ Includes 14 // Other libraries and framework includes 15 // Project includes 16 #include "lldb/Core/DataBufferHeap.h" 17 #include "lldb/Core/Log.h" 18 #include "lldb/Core/RangeMap.h" 19 #include "lldb/Core/State.h" 20 #include "lldb/Target/Process.h" 21 22 using namespace lldb; 23 using namespace lldb_private; 24 25 //---------------------------------------------------------------------- 26 // MemoryCache constructor 27 //---------------------------------------------------------------------- 28 MemoryCache::MemoryCache(Process &process) 29 : m_mutex(), m_L1_cache(), m_L2_cache(), m_invalid_ranges(), 30 m_process(process), 31 m_L2_cache_line_byte_size(process.GetMemoryCacheLineSize()) {} 32 33 //---------------------------------------------------------------------- 34 // Destructor 35 //---------------------------------------------------------------------- 36 MemoryCache::~MemoryCache() {} 37 38 void MemoryCache::Clear(bool clear_invalid_ranges) { 39 std::lock_guard<std::recursive_mutex> guard(m_mutex); 40 m_L1_cache.clear(); 41 m_L2_cache.clear(); 42 if (clear_invalid_ranges) 43 m_invalid_ranges.Clear(); 44 m_L2_cache_line_byte_size = m_process.GetMemoryCacheLineSize(); 45 } 46 47 void MemoryCache::AddL1CacheData(lldb::addr_t addr, const void *src, 48 size_t src_len) { 49 AddL1CacheData( 50 addr, DataBufferSP(new DataBufferHeap(DataBufferHeap(src, src_len)))); 51 } 52 53 void MemoryCache::AddL1CacheData(lldb::addr_t addr, 54 const DataBufferSP &data_buffer_sp) { 55 std::lock_guard<std::recursive_mutex> guard(m_mutex); 56 m_L1_cache[addr] = data_buffer_sp; 57 } 58 59 void MemoryCache::Flush(addr_t addr, size_t size) { 60 if (size == 0) 61 return; 62 63 std::lock_guard<std::recursive_mutex> guard(m_mutex); 64 65 // Erase any blocks from the L1 cache that intersect with the flush range 66 if (!m_L1_cache.empty()) { 67 AddrRange flush_range(addr, size); 68 BlockMap::iterator pos = m_L1_cache.upper_bound(addr); 69 if (pos != m_L1_cache.begin()) { 70 --pos; 71 } 72 while (pos != m_L1_cache.end()) { 73 AddrRange chunk_range(pos->first, pos->second->GetByteSize()); 74 if (!chunk_range.DoesIntersect(flush_range)) 75 break; 76 pos = m_L1_cache.erase(pos); 77 } 78 } 79 80 if (!m_L2_cache.empty()) { 81 const uint32_t cache_line_byte_size = m_L2_cache_line_byte_size; 82 const addr_t end_addr = (addr + size - 1); 83 const addr_t first_cache_line_addr = addr - (addr % cache_line_byte_size); 84 const addr_t last_cache_line_addr = 85 end_addr - (end_addr % cache_line_byte_size); 86 // Watch for overflow where size will cause us to go off the end of the 87 // 64 bit address space 88 uint32_t num_cache_lines; 89 if (last_cache_line_addr >= first_cache_line_addr) 90 num_cache_lines = ((last_cache_line_addr - first_cache_line_addr) / 91 cache_line_byte_size) + 92 1; 93 else 94 num_cache_lines = 95 (UINT64_MAX - first_cache_line_addr + 1) / cache_line_byte_size; 96 97 uint32_t cache_idx = 0; 98 for (addr_t curr_addr = first_cache_line_addr; cache_idx < num_cache_lines; 99 curr_addr += cache_line_byte_size, ++cache_idx) { 100 BlockMap::iterator pos = m_L2_cache.find(curr_addr); 101 if (pos != m_L2_cache.end()) 102 m_L2_cache.erase(pos); 103 } 104 } 105 } 106 107 void MemoryCache::AddInvalidRange(lldb::addr_t base_addr, 108 lldb::addr_t byte_size) { 109 if (byte_size > 0) { 110 std::lock_guard<std::recursive_mutex> guard(m_mutex); 111 InvalidRanges::Entry range(base_addr, byte_size); 112 m_invalid_ranges.Append(range); 113 m_invalid_ranges.Sort(); 114 } 115 } 116 117 bool MemoryCache::RemoveInvalidRange(lldb::addr_t base_addr, 118 lldb::addr_t byte_size) { 119 if (byte_size > 0) { 120 std::lock_guard<std::recursive_mutex> guard(m_mutex); 121 const uint32_t idx = m_invalid_ranges.FindEntryIndexThatContains(base_addr); 122 if (idx != UINT32_MAX) { 123 const InvalidRanges::Entry *entry = m_invalid_ranges.GetEntryAtIndex(idx); 124 if (entry->GetRangeBase() == base_addr && 125 entry->GetByteSize() == byte_size) 126 return m_invalid_ranges.RemoveEntrtAtIndex(idx); 127 } 128 } 129 return false; 130 } 131 132 size_t MemoryCache::Read(addr_t addr, void *dst, size_t dst_len, Error &error) { 133 size_t bytes_left = dst_len; 134 135 // Check the L1 cache for a range that contain the entire memory read. 136 // If we find a range in the L1 cache that does, we use it. Else we fall 137 // back to reading memory in m_L2_cache_line_byte_size byte sized chunks. 138 // The L1 cache contains chunks of memory that are not required to be 139 // m_L2_cache_line_byte_size bytes in size, so we don't try anything 140 // tricky when reading from them (no partial reads from the L1 cache). 141 142 std::lock_guard<std::recursive_mutex> guard(m_mutex); 143 if (!m_L1_cache.empty()) { 144 AddrRange read_range(addr, dst_len); 145 BlockMap::iterator pos = m_L1_cache.upper_bound(addr); 146 if (pos != m_L1_cache.begin()) { 147 --pos; 148 } 149 AddrRange chunk_range(pos->first, pos->second->GetByteSize()); 150 if (chunk_range.Contains(read_range)) { 151 memcpy(dst, pos->second->GetBytes() + addr - chunk_range.GetRangeBase(), 152 dst_len); 153 return dst_len; 154 } 155 } 156 157 // If this memory read request is larger than the cache line size, then 158 // we (1) try to read as much of it at once as possible, and (2) don't 159 // add the data to the memory cache. We don't want to split a big read 160 // up into more separate reads than necessary, and with a large memory read 161 // request, it is unlikely that the caller function will ask for the next 162 // 4 bytes after the large memory read - so there's little benefit to saving 163 // it in the cache. 164 if (dst && dst_len > m_L2_cache_line_byte_size) { 165 size_t bytes_read = 166 m_process.ReadMemoryFromInferior(addr, dst, dst_len, error); 167 // Add this non block sized range to the L1 cache if we actually read 168 // anything 169 if (bytes_read > 0) 170 AddL1CacheData(addr, dst, bytes_read); 171 return bytes_read; 172 } 173 174 if (dst && bytes_left > 0) { 175 const uint32_t cache_line_byte_size = m_L2_cache_line_byte_size; 176 uint8_t *dst_buf = (uint8_t *)dst; 177 addr_t curr_addr = addr - (addr % cache_line_byte_size); 178 addr_t cache_offset = addr - curr_addr; 179 180 while (bytes_left > 0) { 181 if (m_invalid_ranges.FindEntryThatContains(curr_addr)) { 182 error.SetErrorStringWithFormat("memory read failed for 0x%" PRIx64, 183 curr_addr); 184 return dst_len - bytes_left; 185 } 186 187 BlockMap::const_iterator pos = m_L2_cache.find(curr_addr); 188 BlockMap::const_iterator end = m_L2_cache.end(); 189 190 if (pos != end) { 191 size_t curr_read_size = cache_line_byte_size - cache_offset; 192 if (curr_read_size > bytes_left) 193 curr_read_size = bytes_left; 194 195 memcpy(dst_buf + dst_len - bytes_left, 196 pos->second->GetBytes() + cache_offset, curr_read_size); 197 198 bytes_left -= curr_read_size; 199 curr_addr += curr_read_size + cache_offset; 200 cache_offset = 0; 201 202 if (bytes_left > 0) { 203 // Get sequential cache page hits 204 for (++pos; (pos != end) && (bytes_left > 0); ++pos) { 205 assert((curr_addr % cache_line_byte_size) == 0); 206 207 if (pos->first != curr_addr) 208 break; 209 210 curr_read_size = pos->second->GetByteSize(); 211 if (curr_read_size > bytes_left) 212 curr_read_size = bytes_left; 213 214 memcpy(dst_buf + dst_len - bytes_left, pos->second->GetBytes(), 215 curr_read_size); 216 217 bytes_left -= curr_read_size; 218 curr_addr += curr_read_size; 219 220 // We have a cache page that succeeded to read some bytes 221 // but not an entire page. If this happens, we must cap 222 // off how much data we are able to read... 223 if (pos->second->GetByteSize() != cache_line_byte_size) 224 return dst_len - bytes_left; 225 } 226 } 227 } 228 229 // We need to read from the process 230 231 if (bytes_left > 0) { 232 assert((curr_addr % cache_line_byte_size) == 0); 233 std::unique_ptr<DataBufferHeap> data_buffer_heap_ap( 234 new DataBufferHeap(cache_line_byte_size, 0)); 235 size_t process_bytes_read = m_process.ReadMemoryFromInferior( 236 curr_addr, data_buffer_heap_ap->GetBytes(), 237 data_buffer_heap_ap->GetByteSize(), error); 238 if (process_bytes_read == 0) 239 return dst_len - bytes_left; 240 241 if (process_bytes_read != cache_line_byte_size) 242 data_buffer_heap_ap->SetByteSize(process_bytes_read); 243 m_L2_cache[curr_addr] = DataBufferSP(data_buffer_heap_ap.release()); 244 // We have read data and put it into the cache, continue through the 245 // loop again to get the data out of the cache... 246 } 247 } 248 } 249 250 return dst_len - bytes_left; 251 } 252 253 AllocatedBlock::AllocatedBlock(lldb::addr_t addr, uint32_t byte_size, 254 uint32_t permissions, uint32_t chunk_size) 255 : m_addr(addr), m_byte_size(byte_size), m_permissions(permissions), 256 m_chunk_size(chunk_size), m_offset_to_chunk_size() 257 // m_allocated (byte_size / chunk_size) 258 { 259 assert(byte_size > chunk_size); 260 } 261 262 AllocatedBlock::~AllocatedBlock() {} 263 264 lldb::addr_t AllocatedBlock::ReserveBlock(uint32_t size) { 265 addr_t addr = LLDB_INVALID_ADDRESS; 266 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS)); 267 if (size <= m_byte_size) { 268 const uint32_t needed_chunks = CalculateChunksNeededForSize(size); 269 270 if (m_offset_to_chunk_size.empty()) { 271 m_offset_to_chunk_size[0] = needed_chunks; 272 LLDB_LOGV(log, 273 "[1] ({0}) (size = {1} ({1:x})) => offset = {2:x}, {3} " 274 "{4} bit chunks", 275 this, size, 0, needed_chunks, m_chunk_size); 276 addr = m_addr; 277 } else { 278 uint32_t last_offset = 0; 279 OffsetToChunkSize::const_iterator pos = m_offset_to_chunk_size.begin(); 280 OffsetToChunkSize::const_iterator end = m_offset_to_chunk_size.end(); 281 while (pos != end) { 282 if (pos->first > last_offset) { 283 const uint32_t bytes_available = pos->first - last_offset; 284 const uint32_t num_chunks = 285 CalculateChunksNeededForSize(bytes_available); 286 if (num_chunks >= needed_chunks) { 287 m_offset_to_chunk_size[last_offset] = needed_chunks; 288 LLDB_LOGV(log, 289 "[2] ({0}) (size = {1} ({1:x})) => offset = {2:x}, " 290 "{3} {4} bit chunks- num_chunks {5}", 291 this, size, last_offset, needed_chunks, m_chunk_size, 292 m_offset_to_chunk_size.size()); 293 addr = m_addr + last_offset; 294 break; 295 } 296 } 297 298 last_offset = pos->first + pos->second * m_chunk_size; 299 300 if (++pos == end) { 301 // Last entry... 302 const uint32_t chunks_left = 303 CalculateChunksNeededForSize(m_byte_size - last_offset); 304 if (chunks_left >= needed_chunks) { 305 m_offset_to_chunk_size[last_offset] = needed_chunks; 306 LLDB_LOGV(log, 307 "[3] ({0}) (size = {1} ({1:x})) => offset = {2:x}, " 308 "{3} {4} bit chunks- num_chunks {5}", 309 this, size, last_offset, needed_chunks, m_chunk_size, 310 m_offset_to_chunk_size.size()); 311 addr = m_addr + last_offset; 312 break; 313 } 314 } 315 } 316 } 317 // const uint32_t total_chunks = m_allocated.size (); 318 // uint32_t unallocated_idx = 0; 319 // uint32_t allocated_idx = m_allocated.find_first(); 320 // uint32_t first_chunk_idx = UINT32_MAX; 321 // uint32_t num_chunks; 322 // while (1) 323 // { 324 // if (allocated_idx == UINT32_MAX) 325 // { 326 // // No more bits are set starting from unallocated_idx, so 327 // we 328 // // either have enough chunks for the request, or we don't. 329 // // Either way we break out of the while loop... 330 // num_chunks = total_chunks - unallocated_idx; 331 // if (needed_chunks <= num_chunks) 332 // first_chunk_idx = unallocated_idx; 333 // break; 334 // } 335 // else if (allocated_idx > unallocated_idx) 336 // { 337 // // We have some allocated chunks, check if there are 338 // enough 339 // // free chunks to satisfy the request? 340 // num_chunks = allocated_idx - unallocated_idx; 341 // if (needed_chunks <= num_chunks) 342 // { 343 // // Yep, we have enough! 344 // first_chunk_idx = unallocated_idx; 345 // break; 346 // } 347 // } 348 // 349 // while (unallocated_idx < total_chunks) 350 // { 351 // if (m_allocated[unallocated_idx]) 352 // ++unallocated_idx; 353 // else 354 // break; 355 // } 356 // 357 // if (unallocated_idx >= total_chunks) 358 // break; 359 // 360 // allocated_idx = m_allocated.find_next(unallocated_idx); 361 // } 362 // 363 // if (first_chunk_idx != UINT32_MAX) 364 // { 365 // const uint32_t end_bit_idx = unallocated_idx + needed_chunks; 366 // for (uint32_t idx = first_chunk_idx; idx < end_bit_idx; ++idx) 367 // m_allocated.set(idx); 368 // return m_addr + m_chunk_size * first_chunk_idx; 369 // } 370 } 371 372 LLDB_LOGV(log, "({0}) (size = {1} ({1:x})) => {2:x}", this, size, addr); 373 return addr; 374 } 375 376 bool AllocatedBlock::FreeBlock(addr_t addr) { 377 uint32_t offset = addr - m_addr; 378 OffsetToChunkSize::iterator pos = m_offset_to_chunk_size.find(offset); 379 bool success = false; 380 if (pos != m_offset_to_chunk_size.end()) { 381 m_offset_to_chunk_size.erase(pos); 382 success = true; 383 } 384 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS)); 385 LLDB_LOGV(log, "({0}) (addr = {1:x}) => {2}, num_chunks: {3}", this, addr, 386 success, m_offset_to_chunk_size.size()); 387 return success; 388 } 389 390 AllocatedMemoryCache::AllocatedMemoryCache(Process &process) 391 : m_process(process), m_mutex(), m_memory_map() {} 392 393 AllocatedMemoryCache::~AllocatedMemoryCache() {} 394 395 void AllocatedMemoryCache::Clear() { 396 std::lock_guard<std::recursive_mutex> guard(m_mutex); 397 if (m_process.IsAlive()) { 398 PermissionsToBlockMap::iterator pos, end = m_memory_map.end(); 399 for (pos = m_memory_map.begin(); pos != end; ++pos) 400 m_process.DoDeallocateMemory(pos->second->GetBaseAddress()); 401 } 402 m_memory_map.clear(); 403 } 404 405 AllocatedMemoryCache::AllocatedBlockSP 406 AllocatedMemoryCache::AllocatePage(uint32_t byte_size, uint32_t permissions, 407 uint32_t chunk_size, Error &error) { 408 AllocatedBlockSP block_sp; 409 const size_t page_size = 4096; 410 const size_t num_pages = (byte_size + page_size - 1) / page_size; 411 const size_t page_byte_size = num_pages * page_size; 412 413 addr_t addr = m_process.DoAllocateMemory(page_byte_size, permissions, error); 414 415 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS)); 416 if (log) { 417 log->Printf("Process::DoAllocateMemory (byte_size = 0x%8.8" PRIx32 418 ", permissions = %s) => 0x%16.16" PRIx64, 419 (uint32_t)page_byte_size, GetPermissionsAsCString(permissions), 420 (uint64_t)addr); 421 } 422 423 if (addr != LLDB_INVALID_ADDRESS) { 424 block_sp.reset( 425 new AllocatedBlock(addr, page_byte_size, permissions, chunk_size)); 426 m_memory_map.insert(std::make_pair(permissions, block_sp)); 427 } 428 return block_sp; 429 } 430 431 lldb::addr_t AllocatedMemoryCache::AllocateMemory(size_t byte_size, 432 uint32_t permissions, 433 Error &error) { 434 std::lock_guard<std::recursive_mutex> guard(m_mutex); 435 436 addr_t addr = LLDB_INVALID_ADDRESS; 437 std::pair<PermissionsToBlockMap::iterator, PermissionsToBlockMap::iterator> 438 range = m_memory_map.equal_range(permissions); 439 440 for (PermissionsToBlockMap::iterator pos = range.first; pos != range.second; 441 ++pos) { 442 addr = (*pos).second->ReserveBlock(byte_size); 443 if (addr != LLDB_INVALID_ADDRESS) 444 break; 445 } 446 447 if (addr == LLDB_INVALID_ADDRESS) { 448 AllocatedBlockSP block_sp(AllocatePage(byte_size, permissions, 16, error)); 449 450 if (block_sp) 451 addr = block_sp->ReserveBlock(byte_size); 452 } 453 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS)); 454 if (log) 455 log->Printf( 456 "AllocatedMemoryCache::AllocateMemory (byte_size = 0x%8.8" PRIx32 457 ", permissions = %s) => 0x%16.16" PRIx64, 458 (uint32_t)byte_size, GetPermissionsAsCString(permissions), 459 (uint64_t)addr); 460 return addr; 461 } 462 463 bool AllocatedMemoryCache::DeallocateMemory(lldb::addr_t addr) { 464 std::lock_guard<std::recursive_mutex> guard(m_mutex); 465 466 PermissionsToBlockMap::iterator pos, end = m_memory_map.end(); 467 bool success = false; 468 for (pos = m_memory_map.begin(); pos != end; ++pos) { 469 if (pos->second->Contains(addr)) { 470 success = pos->second->FreeBlock(addr); 471 break; 472 } 473 } 474 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS)); 475 if (log) 476 log->Printf("AllocatedMemoryCache::DeallocateMemory (addr = 0x%16.16" PRIx64 477 ") => %i", 478 (uint64_t)addr, success); 479 return success; 480 } 481