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Diffstat (limited to 'toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/cpu_set.h')
-rw-r--r-- | toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/cpu_set.h | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/cpu_set.h b/toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/cpu_set.h new file mode 100644 index 000000000..1cca9aa5a --- /dev/null +++ b/toolkit/crashreporter/google-breakpad/src/client/linux/minidump_writer/cpu_set.h @@ -0,0 +1,144 @@ +// 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_ |