| // Copyright 2016 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // Adapted from: |
| // lbshell/src/platform/linux/posix_emulation/lb_shell/lb_memory_pages_linux.cc |
| |
| #include "starboard/shared/dlmalloc/page_internal.h" |
| |
| #include <stdio.h> |
| #include <sys/mman.h> |
| |
| #include "starboard/atomic.h" |
| #include "starboard/log.h" |
| #include "starboard/memory.h" |
| |
| namespace { |
| |
| int32_t s_tracked_page_count = 0; |
| |
| int32_t GetPageCount(size_t byte_count) { |
| return static_cast<int32_t>(SbMemoryAlignToPageSize(byte_count) / |
| SB_MEMORY_PAGE_SIZE); |
| } |
| |
| int SbMemoryMapFlagsToMmapProtect(int sb_flags) { |
| bool flag_set = false; |
| int mmap_protect = 0; |
| if (sb_flags & kSbMemoryMapProtectRead) { |
| mmap_protect |= PROT_READ; |
| flag_set = true; |
| } |
| if (sb_flags & kSbMemoryMapProtectWrite) { |
| mmap_protect |= PROT_WRITE; |
| flag_set = true; |
| } |
| #if SB_CAN(MAP_EXECUTABLE_MEMORY) |
| if (sb_flags & kSbMemoryMapProtectExec) { |
| mmap_protect |= PROT_EXEC; |
| flag_set = true; |
| } |
| #endif |
| if (!flag_set) { |
| mmap_protect = PROT_NONE; |
| } |
| return mmap_protect; |
| } |
| |
| } // namespace |
| |
| void* SbPageMap(size_t size_bytes, int flags, const char* /*unused_name*/) { |
| void* ret = SbPageMapUntracked(size_bytes, flags, NULL); |
| if (ret != SB_MEMORY_MAP_FAILED) { |
| SbAtomicNoBarrier_Increment(&s_tracked_page_count, |
| GetPageCount(size_bytes)); |
| } |
| return ret; |
| } |
| |
| void* SbPageMapUntracked(size_t size_bytes, |
| int flags, |
| const char* /*unused_name*/) { |
| int mmap_protect = SbMemoryMapFlagsToMmapProtect(flags); |
| void* mem = mmap(0, size_bytes, mmap_protect, MAP_PRIVATE | MAP_ANON, -1, 0); |
| return mem; |
| } |
| |
| bool SbPageUnmap(void* ptr, size_t size_bytes) { |
| SbAtomicNoBarrier_Increment(&s_tracked_page_count, -GetPageCount(size_bytes)); |
| return SbPageUnmapUntracked(ptr, size_bytes); |
| } |
| |
| bool SbPageUnmapUntracked(void* ptr, size_t size_bytes) { |
| return munmap(ptr, size_bytes) == 0; |
| } |
| |
| size_t SbPageGetTotalPhysicalMemoryBytes() { |
| // Limit ourselves to remain similar to more constrained platforms. |
| return 1024U * 1024 * 1024; |
| } |
| |
| int64_t SbPageGetUnallocatedPhysicalMemoryBytes() { |
| // Computes unallocated memory as the total system memory (our fake 1GB limit) |
| // minus the # of resident pages. |
| |
| // statm provides info about our memory usage. |
| // Columns are: size, resident, share, text, lib, data, and dt. |
| // Just consider "resident" pages for our purposes. |
| const char* kStatmPath = "/proc/self/statm"; |
| FILE* f = fopen(kStatmPath, "r"); |
| if (!f) { |
| SB_DLOG(FATAL) << "Failed to open " << kStatmPath; |
| return 0; |
| } |
| size_t program_size = 0; |
| size_t resident = 0; |
| |
| fscanf(f, "%lu %lu", &program_size, &resident); |
| fclose(f); |
| return SbPageGetTotalPhysicalMemoryBytes() - resident * SB_MEMORY_PAGE_SIZE; |
| } |
| |
| size_t SbPageGetMappedBytes() { |
| return static_cast<size_t>(SbAtomicNoBarrier_Load(&s_tracked_page_count) * |
| SB_MEMORY_PAGE_SIZE); |
| } |