1 //===-- Memory.cpp ----------------------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "lldb/Target/Memory.h"
12 #include "lldb/Core/RangeMap.h"
13 #include "lldb/Target/Process.h"
14 #include "lldb/Utility/DataBufferHeap.h"
15 #include "lldb/Utility/Log.h"
16 #include "lldb/Utility/State.h"
19 using namespace lldb_private;
21 //----------------------------------------------------------------------
22 // MemoryCache constructor
23 //----------------------------------------------------------------------
24 MemoryCache::MemoryCache(Process &process)
25 : m_mutex(), m_L1_cache(), m_L2_cache(), m_invalid_ranges(),
27 m_L2_cache_line_byte_size(process.GetMemoryCacheLineSize()) {}
29 //----------------------------------------------------------------------
31 //----------------------------------------------------------------------
32 MemoryCache::~MemoryCache() {}
34 void MemoryCache::Clear(bool clear_invalid_ranges) {
35 std::lock_guard<std::recursive_mutex> guard(m_mutex);
38 if (clear_invalid_ranges)
39 m_invalid_ranges.Clear();
40 m_L2_cache_line_byte_size = m_process.GetMemoryCacheLineSize();
43 void MemoryCache::AddL1CacheData(lldb::addr_t addr, const void *src,
46 addr, DataBufferSP(new DataBufferHeap(DataBufferHeap(src, src_len))));
49 void MemoryCache::AddL1CacheData(lldb::addr_t addr,
50 const DataBufferSP &data_buffer_sp) {
51 std::lock_guard<std::recursive_mutex> guard(m_mutex);
52 m_L1_cache[addr] = data_buffer_sp;
55 void MemoryCache::Flush(addr_t addr, size_t size) {
59 std::lock_guard<std::recursive_mutex> guard(m_mutex);
61 // Erase any blocks from the L1 cache that intersect with the flush range
62 if (!m_L1_cache.empty()) {
63 AddrRange flush_range(addr, size);
64 BlockMap::iterator pos = m_L1_cache.upper_bound(addr);
65 if (pos != m_L1_cache.begin()) {
68 while (pos != m_L1_cache.end()) {
69 AddrRange chunk_range(pos->first, pos->second->GetByteSize());
70 if (!chunk_range.DoesIntersect(flush_range))
72 pos = m_L1_cache.erase(pos);
76 if (!m_L2_cache.empty()) {
77 const uint32_t cache_line_byte_size = m_L2_cache_line_byte_size;
78 const addr_t end_addr = (addr + size - 1);
79 const addr_t first_cache_line_addr = addr - (addr % cache_line_byte_size);
80 const addr_t last_cache_line_addr =
81 end_addr - (end_addr % cache_line_byte_size);
82 // Watch for overflow where size will cause us to go off the end of the
83 // 64 bit address space
84 uint32_t num_cache_lines;
85 if (last_cache_line_addr >= first_cache_line_addr)
86 num_cache_lines = ((last_cache_line_addr - first_cache_line_addr) /
87 cache_line_byte_size) +
91 (UINT64_MAX - first_cache_line_addr + 1) / cache_line_byte_size;
93 uint32_t cache_idx = 0;
94 for (addr_t curr_addr = first_cache_line_addr; cache_idx < num_cache_lines;
95 curr_addr += cache_line_byte_size, ++cache_idx) {
96 BlockMap::iterator pos = m_L2_cache.find(curr_addr);
97 if (pos != m_L2_cache.end())
98 m_L2_cache.erase(pos);
103 void MemoryCache::AddInvalidRange(lldb::addr_t base_addr,
104 lldb::addr_t byte_size) {
106 std::lock_guard<std::recursive_mutex> guard(m_mutex);
107 InvalidRanges::Entry range(base_addr, byte_size);
108 m_invalid_ranges.Append(range);
109 m_invalid_ranges.Sort();
113 bool MemoryCache::RemoveInvalidRange(lldb::addr_t base_addr,
114 lldb::addr_t byte_size) {
116 std::lock_guard<std::recursive_mutex> guard(m_mutex);
117 const uint32_t idx = m_invalid_ranges.FindEntryIndexThatContains(base_addr);
118 if (idx != UINT32_MAX) {
119 const InvalidRanges::Entry *entry = m_invalid_ranges.GetEntryAtIndex(idx);
120 if (entry->GetRangeBase() == base_addr &&
121 entry->GetByteSize() == byte_size)
122 return m_invalid_ranges.RemoveEntrtAtIndex(idx);
128 size_t MemoryCache::Read(addr_t addr, void *dst, size_t dst_len,
130 size_t bytes_left = dst_len;
132 // Check the L1 cache for a range that contain the entire memory read. If we
133 // find a range in the L1 cache that does, we use it. Else we fall back to
134 // reading memory in m_L2_cache_line_byte_size byte sized chunks. The L1
135 // cache contains chunks of memory that are not required to be
136 // m_L2_cache_line_byte_size bytes in size, so we don't try anything tricky
137 // when reading from them (no partial reads from the L1 cache).
139 std::lock_guard<std::recursive_mutex> guard(m_mutex);
140 if (!m_L1_cache.empty()) {
141 AddrRange read_range(addr, dst_len);
142 BlockMap::iterator pos = m_L1_cache.upper_bound(addr);
143 if (pos != m_L1_cache.begin()) {
146 AddrRange chunk_range(pos->first, pos->second->GetByteSize());
147 if (chunk_range.Contains(read_range)) {
148 memcpy(dst, pos->second->GetBytes() + addr - chunk_range.GetRangeBase(),
154 // If this memory read request is larger than the cache line size, then we
155 // (1) try to read as much of it at once as possible, and (2) don't add the
156 // data to the memory cache. We don't want to split a big read up into more
157 // separate reads than necessary, and with a large memory read request, it is
158 // unlikely that the caller function will ask for the next
159 // 4 bytes after the large memory read - so there's little benefit to saving
161 if (dst && dst_len > m_L2_cache_line_byte_size) {
163 m_process.ReadMemoryFromInferior(addr, dst, dst_len, error);
164 // Add this non block sized range to the L1 cache if we actually read
167 AddL1CacheData(addr, dst, bytes_read);
171 if (dst && bytes_left > 0) {
172 const uint32_t cache_line_byte_size = m_L2_cache_line_byte_size;
173 uint8_t *dst_buf = (uint8_t *)dst;
174 addr_t curr_addr = addr - (addr % cache_line_byte_size);
175 addr_t cache_offset = addr - curr_addr;
177 while (bytes_left > 0) {
178 if (m_invalid_ranges.FindEntryThatContains(curr_addr)) {
179 error.SetErrorStringWithFormat("memory read failed for 0x%" PRIx64,
181 return dst_len - bytes_left;
184 BlockMap::const_iterator pos = m_L2_cache.find(curr_addr);
185 BlockMap::const_iterator end = m_L2_cache.end();
188 size_t curr_read_size = cache_line_byte_size - cache_offset;
189 if (curr_read_size > bytes_left)
190 curr_read_size = bytes_left;
192 memcpy(dst_buf + dst_len - bytes_left,
193 pos->second->GetBytes() + cache_offset, curr_read_size);
195 bytes_left -= curr_read_size;
196 curr_addr += curr_read_size + cache_offset;
199 if (bytes_left > 0) {
200 // Get sequential cache page hits
201 for (++pos; (pos != end) && (bytes_left > 0); ++pos) {
202 assert((curr_addr % cache_line_byte_size) == 0);
204 if (pos->first != curr_addr)
207 curr_read_size = pos->second->GetByteSize();
208 if (curr_read_size > bytes_left)
209 curr_read_size = bytes_left;
211 memcpy(dst_buf + dst_len - bytes_left, pos->second->GetBytes(),
214 bytes_left -= curr_read_size;
215 curr_addr += curr_read_size;
217 // We have a cache page that succeeded to read some bytes but not
218 // an entire page. If this happens, we must cap off how much data
219 // we are able to read...
220 if (pos->second->GetByteSize() != cache_line_byte_size)
221 return dst_len - bytes_left;
226 // We need to read from the process
228 if (bytes_left > 0) {
229 assert((curr_addr % cache_line_byte_size) == 0);
230 std::unique_ptr<DataBufferHeap> data_buffer_heap_ap(
231 new DataBufferHeap(cache_line_byte_size, 0));
232 size_t process_bytes_read = m_process.ReadMemoryFromInferior(
233 curr_addr, data_buffer_heap_ap->GetBytes(),
234 data_buffer_heap_ap->GetByteSize(), error);
235 if (process_bytes_read == 0)
236 return dst_len - bytes_left;
238 if (process_bytes_read != cache_line_byte_size)
239 data_buffer_heap_ap->SetByteSize(process_bytes_read);
240 m_L2_cache[curr_addr] = DataBufferSP(data_buffer_heap_ap.release());
241 // We have read data and put it into the cache, continue through the
242 // loop again to get the data out of the cache...
247 return dst_len - bytes_left;
250 AllocatedBlock::AllocatedBlock(lldb::addr_t addr, uint32_t byte_size,
251 uint32_t permissions, uint32_t chunk_size)
252 : m_range(addr, byte_size), m_permissions(permissions),
253 m_chunk_size(chunk_size)
255 // The entire address range is free to start with.
256 m_free_blocks.Append(m_range);
257 assert(byte_size > chunk_size);
260 AllocatedBlock::~AllocatedBlock() {}
262 lldb::addr_t AllocatedBlock::ReserveBlock(uint32_t size) {
263 // We must return something valid for zero bytes.
266 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
268 const size_t free_count = m_free_blocks.GetSize();
269 for (size_t i=0; i<free_count; ++i)
271 auto &free_block = m_free_blocks.GetEntryRef(i);
272 const lldb::addr_t range_size = free_block.GetByteSize();
273 if (range_size >= size)
275 // We found a free block that is big enough for our data. Figure out how
276 // many chunks we will need and calculate the resulting block size we
278 addr_t addr = free_block.GetRangeBase();
279 size_t num_chunks = CalculateChunksNeededForSize(size);
280 lldb::addr_t block_size = num_chunks * m_chunk_size;
281 lldb::addr_t bytes_left = range_size - block_size;
284 // The newly allocated block will take all of the bytes in this
285 // available block, so we can just add it to the allocated ranges and
286 // remove the range from the free ranges.
287 m_reserved_blocks.Insert(free_block, false);
288 m_free_blocks.RemoveEntryAtIndex(i);
292 // Make the new allocated range and add it to the allocated ranges.
293 Range<lldb::addr_t, uint32_t> reserved_block(free_block);
294 reserved_block.SetByteSize(block_size);
295 // Insert the reserved range and don't combine it with other blocks in
296 // the reserved blocks list.
297 m_reserved_blocks.Insert(reserved_block, false);
298 // Adjust the free range in place since we won't change the sorted
299 // ordering of the m_free_blocks list.
300 free_block.SetRangeBase(reserved_block.GetRangeEnd());
301 free_block.SetByteSize(bytes_left);
303 LLDB_LOGV(log, "({0}) (size = {1} ({1:x})) => {2:x}", this, size, addr);
308 LLDB_LOGV(log, "({0}) (size = {1} ({1:x})) => {2:x}", this, size,
309 LLDB_INVALID_ADDRESS);
310 return LLDB_INVALID_ADDRESS;
313 bool AllocatedBlock::FreeBlock(addr_t addr) {
314 bool success = false;
315 auto entry_idx = m_reserved_blocks.FindEntryIndexThatContains(addr);
316 if (entry_idx != UINT32_MAX)
318 m_free_blocks.Insert(m_reserved_blocks.GetEntryRef(entry_idx), true);
319 m_reserved_blocks.RemoveEntryAtIndex(entry_idx);
322 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
323 LLDB_LOGV(log, "({0}) (addr = {1:x}) => {2}", this, addr, success);
327 AllocatedMemoryCache::AllocatedMemoryCache(Process &process)
328 : m_process(process), m_mutex(), m_memory_map() {}
330 AllocatedMemoryCache::~AllocatedMemoryCache() {}
332 void AllocatedMemoryCache::Clear() {
333 std::lock_guard<std::recursive_mutex> guard(m_mutex);
334 if (m_process.IsAlive()) {
335 PermissionsToBlockMap::iterator pos, end = m_memory_map.end();
336 for (pos = m_memory_map.begin(); pos != end; ++pos)
337 m_process.DoDeallocateMemory(pos->second->GetBaseAddress());
339 m_memory_map.clear();
342 AllocatedMemoryCache::AllocatedBlockSP
343 AllocatedMemoryCache::AllocatePage(uint32_t byte_size, uint32_t permissions,
344 uint32_t chunk_size, Status &error) {
345 AllocatedBlockSP block_sp;
346 const size_t page_size = 4096;
347 const size_t num_pages = (byte_size + page_size - 1) / page_size;
348 const size_t page_byte_size = num_pages * page_size;
350 addr_t addr = m_process.DoAllocateMemory(page_byte_size, permissions, error);
352 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
354 log->Printf("Process::DoAllocateMemory (byte_size = 0x%8.8" PRIx32
355 ", permissions = %s) => 0x%16.16" PRIx64,
356 (uint32_t)page_byte_size, GetPermissionsAsCString(permissions),
360 if (addr != LLDB_INVALID_ADDRESS) {
362 new AllocatedBlock(addr, page_byte_size, permissions, chunk_size));
363 m_memory_map.insert(std::make_pair(permissions, block_sp));
368 lldb::addr_t AllocatedMemoryCache::AllocateMemory(size_t byte_size,
369 uint32_t permissions,
371 std::lock_guard<std::recursive_mutex> guard(m_mutex);
373 addr_t addr = LLDB_INVALID_ADDRESS;
374 std::pair<PermissionsToBlockMap::iterator, PermissionsToBlockMap::iterator>
375 range = m_memory_map.equal_range(permissions);
377 for (PermissionsToBlockMap::iterator pos = range.first; pos != range.second;
379 addr = (*pos).second->ReserveBlock(byte_size);
380 if (addr != LLDB_INVALID_ADDRESS)
384 if (addr == LLDB_INVALID_ADDRESS) {
385 AllocatedBlockSP block_sp(AllocatePage(byte_size, permissions, 16, error));
388 addr = block_sp->ReserveBlock(byte_size);
390 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
393 "AllocatedMemoryCache::AllocateMemory (byte_size = 0x%8.8" PRIx32
394 ", permissions = %s) => 0x%16.16" PRIx64,
395 (uint32_t)byte_size, GetPermissionsAsCString(permissions),
400 bool AllocatedMemoryCache::DeallocateMemory(lldb::addr_t addr) {
401 std::lock_guard<std::recursive_mutex> guard(m_mutex);
403 PermissionsToBlockMap::iterator pos, end = m_memory_map.end();
404 bool success = false;
405 for (pos = m_memory_map.begin(); pos != end; ++pos) {
406 if (pos->second->Contains(addr)) {
407 success = pos->second->FreeBlock(addr);
411 Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
413 log->Printf("AllocatedMemoryCache::DeallocateMemory (addr = 0x%16.16" PRIx64
415 (uint64_t)addr, success);