| // Copyright (c) 2013, Google Inc. |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following disclaimer |
| // in the documentation and/or other materials provided with the |
| // distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #ifndef CLIENT_LINUX_MINIDUMP_WRITER_CPU_SET_H_ |
| #define CLIENT_LINUX_MINIDUMP_WRITER_CPU_SET_H_ |
| |
| #include <stdint.h> |
| #include <assert.h> |
| #include <string.h> |
| |
| #include "common/linux/linux_libc_support.h" |
| #include "third_party/lss/linux_syscall_support.h" |
| |
| namespace google_breakpad { |
| |
| // Helper class used to model a set of CPUs, as read from sysfs |
| // files like /sys/devices/system/cpu/present |
| // See See http://www.kernel.org/doc/Documentation/cputopology.txt |
| class CpuSet { |
| public: |
| // The maximum number of supported CPUs. |
| static const size_t kMaxCpus = 1024; |
| |
| CpuSet() { |
| my_memset(mask_, 0, sizeof(mask_)); |
| } |
| |
| // Parse a sysfs file to extract the corresponding CPU set. |
| bool ParseSysFile(int fd) { |
| char buffer[512]; |
| int ret = sys_read(fd, buffer, sizeof(buffer)-1); |
| if (ret < 0) |
| return false; |
| |
| buffer[ret] = '\0'; |
| |
| // Expected format: comma-separated list of items, where each |
| // item can be a decimal integer, or two decimal integers separated |
| // by a dash. |
| // E.g.: |
| // 0 |
| // 0,1,2,3 |
| // 0-3 |
| // 1,10-23 |
| const char* p = buffer; |
| const char* p_end = p + ret; |
| while (p < p_end) { |
| // Skip leading space, if any |
| while (p < p_end && my_isspace(*p)) |
| p++; |
| |
| // Find start and size of current item. |
| const char* item = p; |
| size_t item_len = static_cast<size_t>(p_end - p); |
| const char* item_next = |
| static_cast<const char*>(my_memchr(p, ',', item_len)); |
| if (item_next != NULL) { |
| p = item_next + 1; |
| item_len = static_cast<size_t>(item_next - item); |
| } else { |
| p = p_end; |
| item_next = p_end; |
| } |
| |
| // Ignore trailing spaces. |
| while (item_next > item && my_isspace(item_next[-1])) |
| item_next--; |
| |
| // skip empty items. |
| if (item_next == item) |
| continue; |
| |
| // read first decimal value. |
| uintptr_t start = 0; |
| const char* next = my_read_decimal_ptr(&start, item); |
| uintptr_t end = start; |
| if (*next == '-') |
| my_read_decimal_ptr(&end, next+1); |
| |
| while (start <= end) |
| SetBit(start++); |
| } |
| return true; |
| } |
| |
| // Intersect this CPU set with another one. |
| void IntersectWith(const CpuSet& other) { |
| for (size_t nn = 0; nn < kMaskWordCount; ++nn) |
| mask_[nn] &= other.mask_[nn]; |
| } |
| |
| // Return the number of CPUs in this set. |
| int GetCount() { |
| int result = 0; |
| for (size_t nn = 0; nn < kMaskWordCount; ++nn) { |
| result += __builtin_popcount(mask_[nn]); |
| } |
| return result; |
| } |
| |
| private: |
| void SetBit(uintptr_t index) { |
| size_t nn = static_cast<size_t>(index); |
| if (nn < kMaxCpus) |
| mask_[nn / kMaskWordBits] |= (1U << (nn % kMaskWordBits)); |
| } |
| |
| typedef uint32_t MaskWordType; |
| static const size_t kMaskWordBits = 8*sizeof(MaskWordType); |
| static const size_t kMaskWordCount = |
| (kMaxCpus + kMaskWordBits - 1) / kMaskWordBits; |
| |
| MaskWordType mask_[kMaskWordCount]; |
| }; |
| |
| } // namespace google_breakpad |
| |
| #endif // CLIENT_LINUX_MINIDUMP_WRITER_CPU_SET_H_ |