| // Copyright (c) 2008, 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. |
| |
| // --- |
| // Author: Sanjay Ghemawat <opensource@google.com> |
| |
| #include <config.h> |
| #include "span.h" |
| |
| #include <string.h> // for NULL, memset |
| |
| #include "internal_logging.h" // for ASSERT |
| #include "page_heap_allocator.h" // for PageHeapAllocator |
| #include "static_vars.h" // for Static |
| |
| namespace tcmalloc { |
| |
| #ifdef SPAN_HISTORY |
| void Event(Span* span, char op, int v = 0) { |
| span->history[span->nexthistory] = op; |
| span->value[span->nexthistory] = v; |
| span->nexthistory++; |
| if (span->nexthistory == sizeof(span->history)) span->nexthistory = 0; |
| } |
| #endif |
| |
| Span* NewSpan(PageID p, Length len) { |
| Span* result = Static::span_allocator()->New(); |
| memset(result, 0, sizeof(*result)); |
| result->start = p; |
| result->length = len; |
| #ifdef SPAN_HISTORY |
| result->nexthistory = 0; |
| #endif |
| return result; |
| } |
| |
| void DeleteSpan(Span* span) { |
| #ifndef NDEBUG |
| // In debug mode, trash the contents of deleted Spans |
| memset(span, 0x3f, sizeof(*span)); |
| #endif |
| Static::span_allocator()->Delete(span); |
| } |
| |
| void DLL_Init(Span* list) { |
| list->next = list; |
| list->prev = list; |
| } |
| |
| void DLL_Remove(Span* span) { |
| span->prev->next = span->next; |
| span->next->prev = span->prev; |
| span->prev = NULL; |
| span->next = NULL; |
| } |
| |
| int DLL_Length(const Span* list) { |
| int result = 0; |
| for (Span* s = list->next; s != list; s = s->next) { |
| result++; |
| } |
| return result; |
| } |
| |
| void DLL_Prepend(Span* list, Span* span) { |
| ASSERT(span->next == NULL); |
| ASSERT(span->prev == NULL); |
| span->next = list->next; |
| span->prev = list; |
| list->next->prev = span; |
| list->next = span; |
| } |
| |
| } // namespace tcmalloc |