X-Git-Url: https://git.llucax.com/software/dgc/cdgc.git/blobdiff_plain/a22fb3227c03bdc818b820bf597277206c03f70b..561273a63d42eff2a91b348781f1927ec0a6d7c6:/gc/gc.d?ds=sidebyside diff --git a/gc/gc.d b/gc/gc.d index 979b81b..e195e25 100644 --- a/gc/gc.d +++ b/gc/gc.d @@ -1,7 +1,7 @@ /** - * This module contains the garbage collector front-end. + * This module contains the garbage collector implementation. * - * Copyright: Copyright (C) 2005-2006 Digital Mars, www.digitalmars.com. + * Copyright: Copyright (C) 2001-2007 Digital Mars, www.digitalmars.com. * All rights reserved. * License: * This software is provided 'as-is', without any express or implied @@ -21,200 +21,3016 @@ * be misrepresented as being the original software. * o This notice may not be removed or altered from any source * distribution. - * Authors: Walter Bright, Sean Kelly + * Authors: Walter Bright, David Friedman, Sean Kelly */ module gc.gc; -import gc.x; +// D Programming Language Garbage Collector implementation + +/************** Debugging ***************************/ + +//debug = PRINTF; // turn on printf's +//debug = COLLECT_PRINTF; // turn on printf's +//debug = THREADINVARIANT; // check thread integrity +//debug = LOGGING; // log allocations / frees +//debug = MEMSTOMP; // stomp on memory +//debug = SENTINEL; // add underrun/overrrun protection +//debug = PTRCHECK; // more pointer checking +//debug = PTRCHECK2; // thorough but slow pointer checking + +/*************** Configuration *********************/ + +version = STACKGROWSDOWN; // growing the stack means subtracting from the stack pointer + // (use for Intel X86 CPUs) + // else growing the stack means adding to the stack pointer +version = MULTI_THREADED; // produce multithreaded version + +/***************************************************/ + +import gc.bits; import gc.stats; -import tango.stdc.stdlib; +import gc.alloc; + +import cstdlib = tango.stdc.stdlib : calloc, free, malloc, realloc; +import cstring = tango.stdc.string : memcpy, memmove, memset; + +debug(THREADINVARIANT) import tango.stdc.posix.pthread; +debug(PRINTF) import tango.stdc.posix.pthread : pthread_self, pthread_t; +debug import tango.stdc.stdio : printf; + +version (GNU) +{ + // BUG: The following import will likely not work, since the gcc + // subdirectory is elsewhere. Instead, perhaps the functions + // could be declared directly or some other resolution could + // be found. + import gcc.builtins; // for __builtin_unwind_init +} + + +struct BlkInfo +{ + void* base; + size_t size; + uint attr; +} + +private +{ + enum BlkAttr : uint + { + FINALIZE = 0b0000_0001, + NO_SCAN = 0b0000_0010, + NO_MOVE = 0b0000_0100, + ALL_BITS = 0b1111_1111 + } + + extern (C) void* rt_stackBottom(); + extern (C) void* rt_stackTop(); + + extern (C) void rt_finalize( void* p, bool det = true ); + + alias void delegate( void*, void* ) scanFn; + + extern (C) void rt_scanStaticData( scanFn scan ); + + version (MULTI_THREADED) + { + extern (C) bool thread_needLock(); + extern (C) void thread_suspendAll(); + extern (C) void thread_resumeAll(); + + extern (C) void thread_scanAll( scanFn fn, void* curStackTop = null ); + } + + extern (C) void onOutOfMemoryError(); + + enum + { + OPFAIL = ~cast(size_t)0 + } +} + + +alias GC gc_t; + + +/* ======================= Leak Detector =========================== */ + + +debug (LOGGING) +{ + struct Log + { + void* p; + size_t size; + size_t line; + char* file; + void* parent; + + void print() + { + printf(" p = %x, size = %d, parent = %x ", p, size, parent); + if (file) + { + printf("%s(%u)", file, line); + } + printf("\n"); + } + } + + + struct LogArray + { + size_t dim; + size_t allocdim; + Log *data; + + void Dtor() + { + if (data) + cstdlib.free(data); + data = null; + } + + void reserve(size_t nentries) + { + assert(dim <= allocdim); + if (allocdim - dim < nentries) + { + allocdim = (dim + nentries) * 2; + assert(dim + nentries <= allocdim); + if (!data) + { + data = cast(Log*)cstdlib.malloc(allocdim * Log.sizeof); + if (!data && allocdim) + onOutOfMemoryError(); + } + else + { Log *newdata; + + newdata = cast(Log*)cstdlib.malloc(allocdim * Log.sizeof); + if (!newdata && allocdim) + onOutOfMemoryError(); + cstring.memcpy(newdata, data, dim * Log.sizeof); + cstdlib.free(data); + data = newdata; + } + } + } + + + void push(Log log) + { + reserve(1); + data[dim++] = log; + } + + void remove(size_t i) + { + cstring.memmove(data + i, data + i + 1, (dim - i) * Log.sizeof); + dim--; + } + + + size_t find(void *p) + { + for (size_t i = 0; i < dim; i++) + { + if (data[i].p == p) + return i; + } + return OPFAIL; // not found + } + + + void copy(LogArray *from) + { + reserve(from.dim - dim); + assert(from.dim <= allocdim); + cstring.memcpy(data, from.data, from.dim * Log.sizeof); + dim = from.dim; + } + } +} + + +/* ============================ GC =============================== */ + + +class GCLock { } // just a dummy so we can get a global lock + + +const uint GCVERSION = 1; // increment every time we change interface + // to GC. + +class GC +{ + // For passing to debug code + static size_t line; + static char* file; + + uint gcversion = GCVERSION; + + Gcx *gcx; // implementation + static ClassInfo gcLock; // global lock + + + void initialize() + { + gcLock = GCLock.classinfo; + gcx = cast(Gcx*)cstdlib.calloc(1, Gcx.sizeof); + if (!gcx) + onOutOfMemoryError(); + gcx.initialize(); + setStackBottom(rt_stackBottom()); + } + + + void Dtor() + { + version (linux) + { + //debug(PRINTF) printf("Thread %x ", pthread_self()); + //debug(PRINTF) printf("GC.Dtor()\n"); + } + + if (gcx) + { + gcx.Dtor(); + cstdlib.free(gcx); + gcx = null; + } + } + + + invariant + { + if (gcx) + { + gcx.thread_Invariant(); + } + } + + + /** + * + */ + void enable() + { + if (!thread_needLock()) + { + assert(gcx.disabled > 0); + gcx.disabled--; + } + else synchronized (gcLock) + { + assert(gcx.disabled > 0); + gcx.disabled--; + } + } + + + /** + * + */ + void disable() + { + if (!thread_needLock()) + { + gcx.disabled++; + } + else synchronized (gcLock) + { + gcx.disabled++; + } + } + + + /** + * + */ + uint getAttr(void* p) + { + if (!p) + { + return 0; + } + + uint go() + { + Pool* pool = gcx.findPool(p); + uint oldb = 0; + + if (pool) + { + auto biti = cast(size_t)(p - pool.baseAddr) / 16; + + oldb = gcx.getBits(pool, biti); + } + return oldb; + } + + if (!thread_needLock()) + { + return go(); + } + else synchronized (gcLock) + { + return go(); + } + } + + + /** + * + */ + uint setAttr(void* p, uint mask) + { + if (!p) + { + return 0; + } + + uint go() + { + Pool* pool = gcx.findPool(p); + uint oldb = 0; + + if (pool) + { + auto biti = cast(size_t)(p - pool.baseAddr) / 16; + + oldb = gcx.getBits(pool, biti); + gcx.setBits(pool, biti, mask); + } + return oldb; + } + + if (!thread_needLock()) + { + return go(); + } + else synchronized (gcLock) + { + return go(); + } + } + + + /** + * + */ + uint clrAttr(void* p, uint mask) + { + if (!p) + { + return 0; + } + + uint go() + { + Pool* pool = gcx.findPool(p); + uint oldb = 0; + + if (pool) + { + auto biti = cast(size_t)(p - pool.baseAddr) / 16; + + oldb = gcx.getBits(pool, biti); + gcx.clrBits(pool, biti, mask); + } + return oldb; + } + + if (!thread_needLock()) + { + return go(); + } + else synchronized (gcLock) + { + return go(); + } + } + + + /** + * + */ + void *malloc(size_t size, uint bits = 0) + { + if (!size) + { + return null; + } + + if (!thread_needLock()) + { + return mallocNoSync(size, bits); + } + else synchronized (gcLock) + { + return mallocNoSync(size, bits); + } + } + + + // + // + // + private void *mallocNoSync(size_t size, uint bits = 0) + { + assert(size != 0); + + void *p = null; + Bins bin; + + //debug(PRINTF) printf("GC::malloc(size = %d, gcx = %p)\n", size, gcx); + assert(gcx); + //debug(PRINTF) printf("gcx.self = %x, pthread_self() = %x\n", gcx.self, pthread_self()); + + size += SENTINEL_EXTRA; + + // Compute size bin + // Cache previous binsize lookup - Dave Fladebo. + static size_t lastsize = -1; + static Bins lastbin; + if (size == lastsize) + bin = lastbin; + else + { + bin = gcx.findBin(size); + lastsize = size; + lastbin = bin; + } + + if (bin < B_PAGE) + { + p = gcx.bucket[bin]; + if (p is null) + { + if (!gcx.allocPage(bin) && !gcx.disabled) // try to find a new page + { + if (!thread_needLock()) + { + /* Then we haven't locked it yet. Be sure + * and lock for a collection, since a finalizer + * may start a new thread. + */ + synchronized (gcLock) + { + gcx.fullcollectshell(); + } + } + else if (!gcx.fullcollectshell()) // collect to find a new page + { + //gcx.newPool(1); + } + } + if (!gcx.bucket[bin] && !gcx.allocPage(bin)) + { int result; + + gcx.newPool(1); // allocate new pool to find a new page + result = gcx.allocPage(bin); + if (!result) + onOutOfMemoryError(); + } + p = gcx.bucket[bin]; + } + + // Return next item from free list + gcx.bucket[bin] = (cast(List*)p).next; + if( !(bits & BlkAttr.NO_SCAN) ) + cstring.memset(p + size, 0, binsize[bin] - size); + //debug(PRINTF) printf("\tmalloc => %x\n", p); + debug (MEMSTOMP) cstring.memset(p, 0xF0, size); + } + else + { + p = gcx.bigAlloc(size); + if (!p) + onOutOfMemoryError(); + } + size -= SENTINEL_EXTRA; + p = sentinel_add(p); + sentinel_init(p, size); + gcx.log_malloc(p, size); + + if (bits) + { + Pool *pool = gcx.findPool(p); + assert(pool); + + gcx.setBits(pool, cast(size_t)(p - pool.baseAddr) / 16, bits); + } + return p; + } + + + /** + * + */ + void *calloc(size_t size, uint bits = 0) + { + if (!size) + { + return null; + } + + if (!thread_needLock()) + { + return callocNoSync(size, bits); + } + else synchronized (gcLock) + { + return callocNoSync(size, bits); + } + } + + + // + // + // + private void *callocNoSync(size_t size, uint bits = 0) + { + assert(size != 0); + + //debug(PRINTF) printf("calloc: %x len %d\n", p, len); + void *p = mallocNoSync(size, bits); + cstring.memset(p, 0, size); + return p; + } + + + /** + * + */ + void *realloc(void *p, size_t size, uint bits = 0) + { + if (!thread_needLock()) + { + return reallocNoSync(p, size, bits); + } + else synchronized (gcLock) + { + return reallocNoSync(p, size, bits); + } + } + + + // + // + // + private void *reallocNoSync(void *p, size_t size, uint bits = 0) + { + if (!size) + { if (p) + { freeNoSync(p); + p = null; + } + } + else if (!p) + { + p = mallocNoSync(size, bits); + } + else + { void *p2; + size_t psize; + + //debug(PRINTF) printf("GC::realloc(p = %x, size = %u)\n", p, size); + version (SENTINEL) + { + sentinel_Invariant(p); + psize = *sentinel_size(p); + if (psize != size) + { + if (psize) + { + Pool *pool = gcx.findPool(p); + + if (pool) + { + auto biti = cast(size_t)(p - pool.baseAddr) / 16; + + if (bits) + { + gcx.clrBits(pool, biti, BlkAttr.ALL_BITS); + gcx.setBits(pool, biti, bits); + } + else + { + bits = gcx.getBits(pool, biti); + } + } + } + p2 = mallocNoSync(size, bits); + if (psize < size) + size = psize; + //debug(PRINTF) printf("\tcopying %d bytes\n",size); + cstring.memcpy(p2, p, size); + p = p2; + } + } + else + { + psize = gcx.findSize(p); // find allocated size + if (psize >= PAGESIZE && size >= PAGESIZE) + { + auto psz = psize / PAGESIZE; + auto newsz = (size + PAGESIZE - 1) / PAGESIZE; + if (newsz == psz) + return p; + + auto pool = gcx.findPool(p); + auto pagenum = (p - pool.baseAddr) / PAGESIZE; + + if (newsz < psz) + { // Shrink in place + synchronized (gcLock) + { + debug (MEMSTOMP) cstring.memset(p + size, 0xF2, psize - size); + pool.freePages(pagenum + newsz, psz - newsz); + } + return p; + } + else if (pagenum + newsz <= pool.npages) + { + // Attempt to expand in place + synchronized (gcLock) + { + for (size_t i = pagenum + psz; 1;) + { + if (i == pagenum + newsz) + { + debug (MEMSTOMP) cstring.memset(p + psize, 0xF0, size - psize); + cstring.memset(&pool.pagetable[pagenum + psz], B_PAGEPLUS, newsz - psz); + return p; + } + if (i == pool.ncommitted) + { + auto u = pool.extendPages(pagenum + newsz - pool.ncommitted); + if (u == OPFAIL) + break; + i = pagenum + newsz; + continue; + } + if (pool.pagetable[i] != B_FREE) + break; + i++; + } + } + } + } + if (psize < size || // if new size is bigger + psize > size * 2) // or less than half + { + if (psize) + { + Pool *pool = gcx.findPool(p); + + if (pool) + { + auto biti = cast(size_t)(p - pool.baseAddr) / 16; + + if (bits) + { + gcx.clrBits(pool, biti, BlkAttr.ALL_BITS); + gcx.setBits(pool, biti, bits); + } + else + { + bits = gcx.getBits(pool, biti); + } + } + } + p2 = mallocNoSync(size, bits); + if (psize < size) + size = psize; + //debug(PRINTF) printf("\tcopying %d bytes\n",size); + cstring.memcpy(p2, p, size); + p = p2; + } + } + } + return p; + } + + + /** + * Attempt to in-place enlarge the memory block pointed to by p by at least + * minbytes beyond its current capacity, up to a maximum of maxsize. This + * does not attempt to move the memory block (like realloc() does). + * + * Returns: + * 0 if could not extend p, + * total size of entire memory block if successful. + */ + size_t extend(void* p, size_t minsize, size_t maxsize) + { + if (!thread_needLock()) + { + return extendNoSync(p, minsize, maxsize); + } + else synchronized (gcLock) + { + return extendNoSync(p, minsize, maxsize); + } + } + + + // + // + // + private size_t extendNoSync(void* p, size_t minsize, size_t maxsize) + in + { + assert( minsize <= maxsize ); + } + body + { + //debug(PRINTF) printf("GC::extend(p = %x, minsize = %u, maxsize = %u)\n", p, minsize, maxsize); + version (SENTINEL) + { + return 0; + } + auto psize = gcx.findSize(p); // find allocated size + if (psize < PAGESIZE) + return 0; // cannot extend buckets + + auto psz = psize / PAGESIZE; + auto minsz = (minsize + PAGESIZE - 1) / PAGESIZE; + auto maxsz = (maxsize + PAGESIZE - 1) / PAGESIZE; + + auto pool = gcx.findPool(p); + auto pagenum = (p - pool.baseAddr) / PAGESIZE; + + size_t sz; + for (sz = 0; sz < maxsz; sz++) + { + auto i = pagenum + psz + sz; + if (i == pool.ncommitted) + break; + if (pool.pagetable[i] != B_FREE) + { if (sz < minsz) + return 0; + break; + } + } + if (sz >= minsz) + { + } + else if (pagenum + psz + sz == pool.ncommitted) + { + auto u = pool.extendPages(minsz - sz); + if (u == OPFAIL) + return 0; + sz = minsz; + } + else + return 0; + debug (MEMSTOMP) cstring.memset(p + psize, 0xF0, (psz + sz) * PAGESIZE - psize); + cstring.memset(pool.pagetable + pagenum + psz, B_PAGEPLUS, sz); + gcx.p_cache = null; + gcx.size_cache = 0; + return (psz + sz) * PAGESIZE; + } + + + /** + * + */ + size_t reserve(size_t size) + { + if (!size) + { + return 0; + } + + if (!thread_needLock()) + { + return reserveNoSync(size); + } + else synchronized (gcLock) + { + return reserveNoSync(size); + } + } + + + // + // + // + private size_t reserveNoSync(size_t size) + { + assert(size != 0); + assert(gcx); + + return gcx.reserve(size); + } + + + /** + * + */ + void free(void *p) + { + if (!p) + { + return; + } + + if (!thread_needLock()) + { + return freeNoSync(p); + } + else synchronized (gcLock) + { + return freeNoSync(p); + } + } + + + // + // + // + private void freeNoSync(void *p) + { + assert (p); + + Pool* pool; + size_t pagenum; + Bins bin; + size_t biti; + + // Find which page it is in + pool = gcx.findPool(p); + if (!pool) // if not one of ours + return; // ignore + sentinel_Invariant(p); + p = sentinel_sub(p); + pagenum = cast(size_t)(p - pool.baseAddr) / PAGESIZE; + biti = cast(size_t)(p - pool.baseAddr) / 16; + gcx.clrBits(pool, biti, BlkAttr.ALL_BITS); + + bin = cast(Bins)pool.pagetable[pagenum]; + if (bin == B_PAGE) // if large alloc + { size_t npages; + size_t n; + + // Free pages + npages = 1; + n = pagenum; + while (++n < pool.ncommitted && pool.pagetable[n] == B_PAGEPLUS) + npages++; + debug (MEMSTOMP) cstring.memset(p, 0xF2, npages * PAGESIZE); + pool.freePages(pagenum, npages); + } + else + { // Add to free list + List *list = cast(List*)p; + + debug (MEMSTOMP) cstring.memset(p, 0xF2, binsize[bin]); + + list.next = gcx.bucket[bin]; + gcx.bucket[bin] = list; + } + gcx.log_free(sentinel_add(p)); + } + + + /** + * Determine the base address of the block containing p. If p is not a gc + * allocated pointer, return null. + */ + void* addrOf(void *p) + { + if (!p) + { + return null; + } + + if (!thread_needLock()) + { + return addrOfNoSync(p); + } + else synchronized (gcLock) + { + return addrOfNoSync(p); + } + } + + + // + // + // + void* addrOfNoSync(void *p) + { + if (!p) + { + return null; + } + + return gcx.findBase(p); + } + + + /** + * Determine the allocated size of pointer p. If p is an interior pointer + * or not a gc allocated pointer, return 0. + */ + size_t sizeOf(void *p) + { + if (!p) + { + return 0; + } + + if (!thread_needLock()) + { + return sizeOfNoSync(p); + } + else synchronized (gcLock) + { + return sizeOfNoSync(p); + } + } + + + // + // + // + private size_t sizeOfNoSync(void *p) + { + assert (p); + + version (SENTINEL) + { + p = sentinel_sub(p); + size_t size = gcx.findSize(p); + + // Check for interior pointer + // This depends on: + // 1) size is a power of 2 for less than PAGESIZE values + // 2) base of memory pool is aligned on PAGESIZE boundary + if (cast(size_t)p & (size - 1) & (PAGESIZE - 1)) + size = 0; + return size ? size - SENTINEL_EXTRA : 0; + } + else + { + if (p == gcx.p_cache) + return gcx.size_cache; + + size_t size = gcx.findSize(p); + + // Check for interior pointer + // This depends on: + // 1) size is a power of 2 for less than PAGESIZE values + // 2) base of memory pool is aligned on PAGESIZE boundary + if (cast(size_t)p & (size - 1) & (PAGESIZE - 1)) + size = 0; + else + { + gcx.p_cache = p; + gcx.size_cache = size; + } + + return size; + } + } + + + /** + * Determine the base address of the block containing p. If p is not a gc + * allocated pointer, return null. + */ + BlkInfo query(void *p) + { + if (!p) + { + BlkInfo i; + return i; + } + + if (!thread_needLock()) + { + return queryNoSync(p); + } + else synchronized (gcLock) + { + return queryNoSync(p); + } + } + + + // + // + // + BlkInfo queryNoSync(void *p) + { + assert(p); + + return gcx.getInfo(p); + } + + + /** + * Verify that pointer p: + * 1) belongs to this memory pool + * 2) points to the start of an allocated piece of memory + * 3) is not on a free list + */ + void check(void *p) + { + if (!p) + { + return; + } + + if (!thread_needLock()) + { + checkNoSync(p); + } + else synchronized (gcLock) + { + checkNoSync(p); + } + } + + + // + // + // + private void checkNoSync(void *p) + { + assert(p); + + sentinel_Invariant(p); + debug (PTRCHECK) + { + Pool* pool; + size_t pagenum; + Bins bin; + size_t size; + + p = sentinel_sub(p); + pool = gcx.findPool(p); + assert(pool); + pagenum = cast(size_t)(p - pool.baseAddr) / PAGESIZE; + bin = cast(Bins)pool.pagetable[pagenum]; + assert(bin <= B_PAGE); + size = binsize[bin]; + assert((cast(size_t)p & (size - 1)) == 0); + + debug (PTRCHECK2) + { + if (bin < B_PAGE) + { + // Check that p is not on a free list + List *list; + + for (list = gcx.bucket[bin]; list; list = list.next) + { + assert(cast(void*)list != p); + } + } + } + } + } + + + // + // + // + private void setStackBottom(void *p) + { + version (STACKGROWSDOWN) + { + //p = (void *)((uint *)p + 4); + if (p > gcx.stackBottom) + { + //debug(PRINTF) printf("setStackBottom(%x)\n", p); + gcx.stackBottom = p; + } + } + else + { + //p = (void *)((uint *)p - 4); + if (p < gcx.stackBottom) + { + //debug(PRINTF) printf("setStackBottom(%x)\n", p); + gcx.stackBottom = cast(char*)p; + } + } + } + + + /** + * add p to list of roots + */ + void addRoot(void *p) + { + if (!p) + { + return; + } + + if (!thread_needLock()) + { + gcx.addRoot(p); + } + else synchronized (gcLock) + { + gcx.addRoot(p); + } + } + + + /** + * remove p from list of roots + */ + void removeRoot(void *p) + { + if (!p) + { + return; + } + + if (!thread_needLock()) + { + gcx.removeRoot(p); + } + else synchronized (gcLock) + { + gcx.removeRoot(p); + } + } + + + /** + * add range to scan for roots + */ + void addRange(void *p, size_t sz) + { + if (!p || !sz) + { + return; + } + + //debug(PRINTF) printf("+GC.addRange(pbot = x%x, ptop = x%x)\n", pbot, ptop); + if (!thread_needLock()) + { + gcx.addRange(p, p + sz); + } + else synchronized (gcLock) + { + gcx.addRange(p, p + sz); + } + //debug(PRINTF) printf("-GC.addRange()\n"); + } + + + /** + * remove range + */ + void removeRange(void *p) + { + if (!p) + { + return; + } + + if (!thread_needLock()) + { + gcx.removeRange(p); + } + else synchronized (gcLock) + { + gcx.removeRange(p); + } + } + + + /** + * do full garbage collection + */ + void fullCollect() + { + debug(PRINTF) printf("GC.fullCollect()\n"); + + if (!thread_needLock()) + { + gcx.fullcollectshell(); + } + else synchronized (gcLock) + { + gcx.fullcollectshell(); + } + + version (none) + { + GCStats stats; + + getStats(stats); + debug(PRINTF) printf("poolsize = %x, usedsize = %x, freelistsize = %x\n", + stats.poolsize, stats.usedsize, stats.freelistsize); + } + + gcx.log_collect(); + } + + + /** + * do full garbage collection ignoring roots + */ + void fullCollectNoStack() + { + if (!thread_needLock()) + { + gcx.noStack++; + gcx.fullcollectshell(); + gcx.noStack--; + } + else synchronized (gcLock) + { + gcx.noStack++; + gcx.fullcollectshell(); + gcx.noStack--; + } + } + + + /** + * minimize free space usage + */ + void minimize() + { + if (!thread_needLock()) + { + gcx.minimize(); + } + else synchronized (gcLock) + { + gcx.minimize(); + } + } + + + /** + * Retrieve statistics about garbage collection. + * Useful for debugging and tuning. + */ + void getStats(out GCStats stats) + { + if (!thread_needLock()) + { + getStatsNoSync(stats); + } + else synchronized (gcLock) + { + getStatsNoSync(stats); + } + } + + + // + // + // + private void getStatsNoSync(out GCStats stats) + { + size_t psize = 0; + size_t usize = 0; + size_t flsize = 0; + + size_t n; + size_t bsize = 0; + + //debug(PRINTF) printf("getStats()\n"); + cstring.memset(&stats, 0, GCStats.sizeof); + + for (n = 0; n < gcx.npools; n++) + { Pool *pool = gcx.pooltable[n]; + + psize += pool.ncommitted * PAGESIZE; + for (size_t j = 0; j < pool.ncommitted; j++) + { + Bins bin = cast(Bins)pool.pagetable[j]; + if (bin == B_FREE) + stats.freeblocks++; + else if (bin == B_PAGE) + stats.pageblocks++; + else if (bin < B_PAGE) + bsize += PAGESIZE; + } + } + + for (n = 0; n < B_PAGE; n++) + { + //debug(PRINTF) printf("bin %d\n", n); + for (List *list = gcx.bucket[n]; list; list = list.next) + { + //debug(PRINTF) printf("\tlist %x\n", list); + flsize += binsize[n]; + } + } + + usize = bsize - flsize; + + stats.poolsize = psize; + stats.usedsize = bsize - flsize; + stats.freelistsize = flsize; + } +} + + +/* ============================ Gcx =============================== */ + +enum +{ PAGESIZE = 4096, + COMMITSIZE = (4096*16), + POOLSIZE = (4096*256), +} + + +enum +{ + B_16, + B_32, + B_64, + B_128, + B_256, + B_512, + B_1024, + B_2048, + B_PAGE, // start of large alloc + B_PAGEPLUS, // continuation of large alloc + B_FREE, // free page + B_UNCOMMITTED, // memory not committed for this page + B_MAX +} + + +alias ubyte Bins; + + +struct List +{ + List *next; +} + + +struct Range +{ + void *pbot; + void *ptop; +} + + +const uint binsize[B_MAX] = [ 16,32,64,128,256,512,1024,2048,4096 ]; +const uint notbinsize[B_MAX] = [ ~(16u-1),~(32u-1),~(64u-1),~(128u-1),~(256u-1), + ~(512u-1),~(1024u-1),~(2048u-1),~(4096u-1) ]; + +/* ============================ Gcx =============================== */ + + +struct Gcx +{ + debug (THREADINVARIANT) + { + pthread_t self; + void thread_Invariant() + { + if (self != pthread_self()) + printf("thread_Invariant(): gcx = %x, self = %x, pthread_self() = %x\n", this, self, pthread_self()); + assert(self == pthread_self()); + } + } + else + { + void thread_Invariant() { } + } + + void *p_cache; + size_t size_cache; + + size_t nroots; + size_t rootdim; + void **roots; + + size_t nranges; + size_t rangedim; + Range *ranges; + + uint noStack; // !=0 means don't scan stack + uint log; // turn on logging + uint anychanges; + void *stackBottom; + uint inited; + int disabled; // turn off collections if >0 + + byte *minAddr; // min(baseAddr) + byte *maxAddr; // max(topAddr) + + size_t npools; + Pool **pooltable; + + List *bucket[B_MAX]; // free list for each size + + + void initialize() + { int dummy; + + (cast(byte*)this)[0 .. Gcx.sizeof] = 0; + stackBottom = cast(char*)&dummy; + log_init(); + debug (THREADINVARIANT) + self = pthread_self(); + //printf("gcx = %p, self = %x\n", this, self); + inited = 1; + } + + + void Dtor() + { + inited = 0; + + for (size_t i = 0; i < npools; i++) + { Pool *pool = pooltable[i]; + + pool.Dtor(); + cstdlib.free(pool); + } + if (pooltable) + cstdlib.free(pooltable); + + if (roots) + cstdlib.free(roots); + + if (ranges) + cstdlib.free(ranges); + } + + + void Invariant() { } + + + invariant + { + if (inited) + { + //printf("Gcx.invariant(): this = %p\n", this); + size_t i; + + // Assure we're called on the right thread + debug (THREADINVARIANT) assert(self == pthread_self()); + + for (i = 0; i < npools; i++) + { Pool *pool = pooltable[i]; + + pool.Invariant(); + if (i == 0) + { + assert(minAddr == pool.baseAddr); + } + if (i + 1 < npools) + { + assert(pool.opCmp(pooltable[i + 1]) < 0); + } + else if (i + 1 == npools) + { + assert(maxAddr == pool.topAddr); + } + } + + if (roots) + { + assert(rootdim != 0); + assert(nroots <= rootdim); + } + + if (ranges) + { + assert(rangedim != 0); + assert(nranges <= rangedim); + + for (i = 0; i < nranges; i++) + { + assert(ranges[i].pbot); + assert(ranges[i].ptop); + assert(ranges[i].pbot <= ranges[i].ptop); + } + } + + for (i = 0; i < B_PAGE; i++) + { + for (List *list = bucket[i]; list; list = list.next) + { + } + } + } + } + + + /** + * + */ + void addRoot(void *p) + { + if (nroots == rootdim) + { + size_t newdim = rootdim * 2 + 16; + void** newroots; + + newroots = cast(void**)cstdlib.malloc(newdim * newroots[0].sizeof); + if (!newroots) + onOutOfMemoryError(); + if (roots) + { cstring.memcpy(newroots, roots, nroots * newroots[0].sizeof); + cstdlib.free(roots); + } + roots = newroots; + rootdim = newdim; + } + roots[nroots] = p; + nroots++; + } + + + /** + * + */ + void removeRoot(void *p) + { + for (size_t i = nroots; i--;) + { + if (roots[i] == p) + { + nroots--; + cstring.memmove(roots + i, roots + i + 1, (nroots - i) * roots[0].sizeof); + return; + } + } + assert(0); + } + + + /** + * + */ + void addRange(void *pbot, void *ptop) + { + debug(PRINTF) printf("Thread %x ", pthread_self()); + debug(PRINTF) printf("%x.Gcx::addRange(%x, %x), nranges = %d\n", this, pbot, ptop, nranges); + if (nranges == rangedim) + { + size_t newdim = rangedim * 2 + 16; + Range *newranges; + + newranges = cast(Range*)cstdlib.malloc(newdim * newranges[0].sizeof); + if (!newranges) + onOutOfMemoryError(); + if (ranges) + { cstring.memcpy(newranges, ranges, nranges * newranges[0].sizeof); + cstdlib.free(ranges); + } + ranges = newranges; + rangedim = newdim; + } + ranges[nranges].pbot = pbot; + ranges[nranges].ptop = ptop; + nranges++; + } + + + /** + * + */ + void removeRange(void *pbot) + { + debug(PRINTF) printf("Thread %x ", pthread_self()); + debug(PRINTF) printf("%x.Gcx.removeRange(%x), nranges = %d\n", this, pbot, nranges); + for (size_t i = nranges; i--;) + { + if (ranges[i].pbot == pbot) + { + nranges--; + cstring.memmove(ranges + i, ranges + i + 1, (nranges - i) * ranges[0].sizeof); + return; + } + } + debug(PRINTF) printf("Wrong thread\n"); + + // This is a fatal error, but ignore it. + // The problem is that we can get a Close() call on a thread + // other than the one the range was allocated on. + //assert(zero); + } + + + /** + * Find Pool that pointer is in. + * Return null if not in a Pool. + * Assume pooltable[] is sorted. + */ + Pool *findPool(void *p) + { + if (p >= minAddr && p < maxAddr) + { + if (npools == 1) + { + return pooltable[0]; + } + + for (size_t i = 0; i < npools; i++) + { Pool *pool; + + pool = pooltable[i]; + if (p < pool.topAddr) + { if (pool.baseAddr <= p) + return pool; + break; + } + } + } + return null; + } + + + /** + * Find base address of block containing pointer p. + * Returns null if not a gc'd pointer + */ + void* findBase(void *p) + { + Pool *pool; + + pool = findPool(p); + if (pool) + { + size_t offset = cast(size_t)(p - pool.baseAddr); + size_t pn = offset / PAGESIZE; + Bins bin = cast(Bins)pool.pagetable[pn]; + + // Adjust bit to be at start of allocated memory block + if (bin <= B_PAGE) + { + return pool.baseAddr + (offset & notbinsize[bin]); + } + else if (bin == B_PAGEPLUS) + { + do + { --pn, offset -= PAGESIZE; + } while (cast(Bins)pool.pagetable[pn] == B_PAGEPLUS); + + return pool.baseAddr + (offset & (offset.max ^ (PAGESIZE-1))); + } + else + { + // we are in a B_FREE or B_UNCOMMITTED page + return null; + } + } + return null; + } + + + /** + * Find size of pointer p. + * Returns 0 if not a gc'd pointer + */ + size_t findSize(void *p) + { + Pool* pool; + size_t size = 0; + + pool = findPool(p); + if (pool) + { + size_t pagenum; + Bins bin; + + pagenum = cast(size_t)(p - pool.baseAddr) / PAGESIZE; + bin = cast(Bins)pool.pagetable[pagenum]; + size = binsize[bin]; + if (bin == B_PAGE) + { size_t npages = pool.ncommitted; + ubyte* pt; + size_t i; + + pt = &pool.pagetable[0]; + for (i = pagenum + 1; i < npages; i++) + { + if (pt[i] != B_PAGEPLUS) + break; + } + size = (i - pagenum) * PAGESIZE; + } + } + return size; + } + + + /** + * + */ + BlkInfo getInfo(void* p) + { + Pool* pool; + BlkInfo info; + + pool = findPool(p); + if (pool) + { + size_t offset = cast(size_t)(p - pool.baseAddr); + size_t pn = offset / PAGESIZE; + Bins bin = cast(Bins)pool.pagetable[pn]; + + //////////////////////////////////////////////////////////////////// + // findAddr + //////////////////////////////////////////////////////////////////// + + if (bin <= B_PAGE) + { + info.base = pool.baseAddr + (offset & notbinsize[bin]); + } + else if (bin == B_PAGEPLUS) + { + do + { --pn, offset -= PAGESIZE; + } while (cast(Bins)pool.pagetable[pn] == B_PAGEPLUS); + + info.base = pool.baseAddr + (offset & (offset.max ^ (PAGESIZE-1))); + + // fix bin for use by size calc below + bin = cast(Bins)pool.pagetable[pn]; + } + + //////////////////////////////////////////////////////////////////// + // findSize + //////////////////////////////////////////////////////////////////// + + info.size = binsize[bin]; + if (bin == B_PAGE) + { size_t npages = pool.ncommitted; + ubyte* pt; + size_t i; + + pt = &pool.pagetable[0]; + for (i = pn + 1; i < npages; i++) + { + if (pt[i] != B_PAGEPLUS) + break; + } + info.size = (i - pn) * PAGESIZE; + } + + //////////////////////////////////////////////////////////////////// + // getBits + //////////////////////////////////////////////////////////////////// + + info.attr = getBits(pool, cast(size_t)(offset / 16)); + } + return info; + } + + + /** + * Compute bin for size. + */ + static Bins findBin(size_t size) + { Bins bin; + + if (size <= 256) + { + if (size <= 64) + { + if (size <= 16) + bin = B_16; + else if (size <= 32) + bin = B_32; + else + bin = B_64; + } + else + { + if (size <= 128) + bin = B_128; + else + bin = B_256; + } + } + else + { + if (size <= 1024) + { + if (size <= 512) + bin = B_512; + else + bin = B_1024; + } + else + { + if (size <= 2048) + bin = B_2048; + else + bin = B_PAGE; + } + } + return bin; + } -version=GCCLASS; -version (GCCLASS) - alias GC gc_t; -else - alias GC* gc_t; + /** + * Allocate a new pool of at least size bytes. + * Sort it into pooltable[]. + * Mark all memory in the pool as B_FREE. + * Return the actual number of bytes reserved or 0 on error. + */ + size_t reserve(size_t size) + { + size_t npages = (size + PAGESIZE - 1) / PAGESIZE; + Pool* pool = newPool(npages); -gc_t _gc; + if (!pool || pool.extendPages(npages) == OPFAIL) + return 0; + return pool.ncommitted * PAGESIZE; + } -private int _termCleanupLevel=1; -/// sets the cleanup level done by gc -/// (0: none, 1: fullCollect, 2: fullCollectNoStack (might crash daemonThreads)) -/// result !=0 if the value was invalid -extern (C) int gc_setTermCleanupLevel(int cLevel){ - if (cLevel<0 || cLevel>2) return cLevel; - _termCleanupLevel=cLevel; - return 0; -} + /** + * Minimizes physical memory usage by returning free pools to the OS. + */ + void minimize() + { + size_t n; + size_t pn; + Pool* pool; + size_t ncommitted; -/// returns the cleanup level done by gc -extern (C) int gc_getTermCleanupLevel(){ - return _termCleanupLevel; -} + for (n = 0; n < npools; n++) + { + pool = pooltable[n]; + ncommitted = pool.ncommitted; + for (pn = 0; pn < ncommitted; pn++) + { + if (cast(Bins)pool.pagetable[pn] != B_FREE) + break; + } + if (pn < ncommitted) + { + n++; + continue; + } + pool.Dtor(); + cstdlib.free(pool); + cstring.memmove(pooltable + n, + pooltable + n + 1, + (--npools - n) * (Pool*).sizeof); + minAddr = pooltable[0].baseAddr; + maxAddr = pooltable[npools - 1].topAddr; + } + } -version (DigitalMars) version(OSX) { - extern(C) void _d_osx_image_init(); -} -extern (C) void thread_init(); + /** + * Allocate a chunk of memory that is larger than a page. + * Return null if out of memory. + */ + void *bigAlloc(size_t size) + { + Pool* pool; + size_t npages; + size_t n; + size_t pn; + size_t freedpages; + void* p; + int state; -extern (C) void gc_init() -{ - version (GCCLASS) - { void* p; - ClassInfo ci = GC.classinfo; + npages = (size + PAGESIZE - 1) / PAGESIZE; + + for (state = 0; ; ) + { + // This code could use some refinement when repeatedly + // allocating very large arrays. + + for (n = 0; n < npools; n++) + { + pool = pooltable[n]; + pn = pool.allocPages(npages); + if (pn != OPFAIL) + goto L1; + } - p = tango.stdc.stdlib.malloc(ci.init.length); - (cast(byte*)p)[0 .. ci.init.length] = ci.init[]; - _gc = cast(GC)p; + // Failed + switch (state) + { + case 0: + if (disabled) + { state = 1; + continue; + } + // Try collecting + freedpages = fullcollectshell(); + if (freedpages >= npools * ((POOLSIZE / PAGESIZE) / 4)) + { state = 1; + continue; + } + // Release empty pools to prevent bloat + minimize(); + // Allocate new pool + pool = newPool(npages); + if (!pool) + { state = 2; + continue; + } + pn = pool.allocPages(npages); + assert(pn != OPFAIL); + goto L1; + case 1: + // Release empty pools to prevent bloat + minimize(); + // Allocate new pool + pool = newPool(npages); + if (!pool) + goto Lnomemory; + pn = pool.allocPages(npages); + assert(pn != OPFAIL); + goto L1; + case 2: + goto Lnomemory; + default: + assert(false); + } + } + + L1: + pool.pagetable[pn] = B_PAGE; + if (npages > 1) + cstring.memset(&pool.pagetable[pn + 1], B_PAGEPLUS, npages - 1); + p = pool.baseAddr + pn * PAGESIZE; + cstring.memset(cast(char *)p + size, 0, npages * PAGESIZE - size); + debug (MEMSTOMP) cstring.memset(p, 0xF1, size); + //debug(PRINTF) printf("\tp = %x\n", p); + return p; + + Lnomemory: + return null; // let mallocNoSync handle the error } - else + + + /** + * Allocate a new pool with at least npages in it. + * Sort it into pooltable[]. + * Return null if failed. + */ + Pool *newPool(size_t npages) { - _gc = cast(GC*) tango.stdc.stdlib.calloc(1, GC.sizeof); + Pool* pool; + Pool** newpooltable; + size_t newnpools; + size_t i; + + //debug(PRINTF) printf("************Gcx::newPool(npages = %d)****************\n", npages); + + // Round up to COMMITSIZE pages + npages = (npages + (COMMITSIZE/PAGESIZE) - 1) & ~(COMMITSIZE/PAGESIZE - 1); + + // Minimum of POOLSIZE + if (npages < POOLSIZE/PAGESIZE) + npages = POOLSIZE/PAGESIZE; + else if (npages > POOLSIZE/PAGESIZE) + { // Give us 150% of requested size, so there's room to extend + auto n = npages + (npages >> 1); + if (n < size_t.max/PAGESIZE) + npages = n; + } + + // Allocate successively larger pools up to 8 megs + if (npools) + { size_t n; + + n = npools; + if (n > 8) + n = 8; // cap pool size at 8 megs + n *= (POOLSIZE / PAGESIZE); + if (npages < n) + npages = n; + } + + pool = cast(Pool *)cstdlib.calloc(1, Pool.sizeof); + if (pool) + { + pool.initialize(npages); + if (!pool.baseAddr) + goto Lerr; + + newnpools = npools + 1; + newpooltable = cast(Pool **)cstdlib.realloc(pooltable, newnpools * (Pool *).sizeof); + if (!newpooltable) + goto Lerr; + + // Sort pool into newpooltable[] + for (i = 0; i < npools; i++) + { + if (pool.opCmp(newpooltable[i]) < 0) + break; + } + cstring.memmove(newpooltable + i + 1, newpooltable + i, (npools - i) * (Pool *).sizeof); + newpooltable[i] = pool; + + pooltable = newpooltable; + npools = newnpools; + + minAddr = pooltable[0].baseAddr; + maxAddr = pooltable[npools - 1].topAddr; + } + return pool; + + Lerr: + pool.Dtor(); + cstdlib.free(pool); + return null; } - _gc.initialize(); - version (DigitalMars) version(OSX) { - _d_osx_image_init(); + + + /** + * Allocate a page of bin's. + * Returns: + * 0 failed + */ + int allocPage(Bins bin) + { + Pool* pool; + size_t n; + size_t pn; + byte* p; + byte* ptop; + + //debug(PRINTF) printf("Gcx::allocPage(bin = %d)\n", bin); + for (n = 0; n < npools; n++) + { + pool = pooltable[n]; + pn = pool.allocPages(1); + if (pn != OPFAIL) + goto L1; + } + return 0; // failed + + L1: + pool.pagetable[pn] = cast(ubyte)bin; + + // Convert page to free list + size_t size = binsize[bin]; + List **b = &bucket[bin]; + + p = pool.baseAddr + pn * PAGESIZE; + ptop = p + PAGESIZE; + for (; p < ptop; p += size) + { + (cast(List *)p).next = *b; + *b = cast(List *)p; + } + return 1; } - // NOTE: The GC must initialize the thread library - // before its first collection. - thread_init(); -} -extern (C) void gc_term() -{ - if (_termCleanupLevel<1) { - // no cleanup - } else if (_termCleanupLevel==2){ - // a more complete cleanup - // NOTE: There may be daemons threads still running when this routine is - // called. If so, cleaning memory out from under then is a good - // way to make them crash horribly. - // Often this probably doesn't matter much since the app is - // supposed to be shutting down anyway, but for example tests might - // crash (and be considerd failed even if the test was ok). - // thus this is not the default and should be enabled by - // I'm disabling cleanup for now until I can think about it some - // more. - // - _gc.fullCollectNoStack(); // not really a 'collect all' -- still scans - // static data area, roots, and ranges. - _gc.Dtor(); - } else { - // default (safe) clenup - _gc.fullCollect(); + + /** + * Search a range of memory values and mark any pointers into the GC pool. + */ + void mark(void *pbot, void *ptop) + { + void **p1 = cast(void **)pbot; + void **p2 = cast(void **)ptop; + size_t pcache = 0; + uint changes = 0; + + //printf("marking range: %p -> %p\n", pbot, ptop); + for (; p1 < p2; p1++) + { + Pool *pool; + byte *p = cast(byte *)(*p1); + + //if (log) debug(PRINTF) printf("\tmark %x\n", p); + if (p >= minAddr && p < maxAddr) + { + if ((cast(size_t)p & ~(PAGESIZE-1)) == pcache) + continue; + + pool = findPool(p); + if (pool) + { + size_t offset = cast(size_t)(p - pool.baseAddr); + size_t biti; + size_t pn = offset / PAGESIZE; + Bins bin = cast(Bins)pool.pagetable[pn]; + + //debug(PRINTF) printf("\t\tfound pool %x, base=%x, pn = %d, bin = %d, biti = x%x\n", pool, pool.baseAddr, pn, bin, biti); + + // Adjust bit to be at start of allocated memory block + if (bin <= B_PAGE) + { + biti = (offset & notbinsize[bin]) >> 4; + //debug(PRINTF) printf("\t\tbiti = x%x\n", biti); + } + else if (bin == B_PAGEPLUS) + { + do + { --pn; + } while (cast(Bins)pool.pagetable[pn] == B_PAGEPLUS); + biti = pn * (PAGESIZE / 16); + } + else + { + // Don't mark bits in B_FREE or B_UNCOMMITTED pages + continue; + } + + if (bin >= B_PAGE) // Cache B_PAGE and B_PAGEPLUS lookups + pcache = cast(size_t)p & ~(PAGESIZE-1); + + //debug(PRINTF) printf("\t\tmark(x%x) = %d\n", biti, pool.mark.test(biti)); + if (!pool.mark.test(biti)) + { + //if (log) debug(PRINTF) printf("\t\tmarking %x\n", p); + pool.mark.set(biti); + if (!pool.noscan.test(biti)) + { + pool.scan.set(biti); + changes = 1; + } + log_parent(sentinel_add(pool.baseAddr + biti * 16), sentinel_add(pbot)); + } + } + } + } + anychanges |= changes; } -} -extern (C) void gc_enable() -{ - _gc.enable(); -} -extern (C) void gc_disable() -{ - _gc.disable(); -} + /** + * Return number of full pages free'd. + */ + size_t fullcollectshell() + { + // The purpose of the 'shell' is to ensure all the registers + // get put on the stack so they'll be scanned + void *sp; + size_t result; + version (GNU) + { + __builtin_unwind_init(); + sp = & sp; + } + else version(LDC) + { + version(X86) + { + uint eax,ecx,edx,ebx,ebp,esi,edi; + asm + { + mov eax[EBP], EAX ; + mov ecx[EBP], ECX ; + mov edx[EBP], EDX ; + mov ebx[EBP], EBX ; + mov ebp[EBP], EBP ; + mov esi[EBP], ESI ; + mov edi[EBP], EDI ; + mov sp[EBP],ESP ; + } + } + else version (X86_64) + { + ulong rax,rbx,rcx,rdx,rbp,rsi,rdi,rsp,r8,r9,r10,r11,r12,r13,r14,r15; + asm + { + movq rax[RBP], RAX ; + movq rbx[RBP], RBX ; + movq rcx[RBP], RCX ; + movq rdx[RBP], RDX ; + movq rbp[RBP], RBP ; + movq rsi[RBP], RSI ; + movq rdi[RBP], RDI ; + movq rsp[RBP], RSP ; + movq r8[RBP], R8 ; + movq r9[RBP], R9 ; + movq r10[RBP], R10 ; + movq r11[RBP], R11 ; + movq r12[RBP], R12 ; + movq r13[RBP], R13 ; + movq r14[RBP], R14 ; + movq r15[RBP], R15 ; + } + } + else + { + static assert( false, "Architecture not supported." ); + } + } + else + { + asm + { + pushad ; + mov sp[EBP],ESP ; + } + } + result = fullcollect(sp); + version (GNU) + { + // nothing to do + } + else version(LDC) + { + // nothing to do + } + else + { + asm + { + popad ; + } + } + return result; + } -extern (C) void gc_collect() -{ - _gc.fullCollect(); -} + /** + * + */ + size_t fullcollect(void *stackTop) + { + size_t n; + Pool* pool; -extern (C) void gc_minimize() -{ - _gc.minimize(); -} + debug(COLLECT_PRINTF) printf("Gcx.fullcollect()\n"); -extern (C) uint gc_getAttr( void* p ) -{ - return _gc.getAttr( p ); -} + thread_suspendAll(); -extern (C) uint gc_setAttr( void* p, uint a ) -{ - return _gc.setAttr( p, a ); -} + p_cache = null; + size_cache = 0; -extern (C) uint gc_clrAttr( void* p, uint a ) -{ - return _gc.clrAttr( p, a ); -} + anychanges = 0; + for (n = 0; n < npools; n++) + { + pool = pooltable[n]; + pool.mark.zero(); + pool.scan.zero(); + pool.freebits.zero(); + } -extern (C) void* gc_malloc( size_t sz, uint ba = 0 ) -{ - return _gc.malloc( sz, ba ); -} + // Mark each free entry, so it doesn't get scanned + for (n = 0; n < B_PAGE; n++) + { + for (List *list = bucket[n]; list; list = list.next) + { + pool = findPool(list); + assert(pool); + pool.freebits.set(cast(size_t)(cast(byte*)list - pool.baseAddr) / 16); + } + } -extern (C) void* gc_calloc( size_t sz, uint ba = 0 ) -{ - return _gc.calloc( sz, ba ); -} + for (n = 0; n < npools; n++) + { + pool = pooltable[n]; + pool.mark.copy(&pool.freebits); + } -extern (C) void* gc_realloc( void* p, size_t sz, uint ba = 0 ) -{ - return _gc.realloc( p, sz, ba ); -} + rt_scanStaticData( &mark ); -extern (C) size_t gc_extend( void* p, size_t mx, size_t sz ) -{ - return _gc.extend( p, mx, sz ); -} + version (MULTI_THREADED) + { + if (!noStack) + { + // Scan stacks and registers for each paused thread + thread_scanAll( &mark, stackTop ); + } + } + else + { + if (!noStack) + { + // Scan stack for main thread + debug(PRINTF) printf(" scan stack bot = %x, top = %x\n", stackTop, stackBottom); + version (STACKGROWSDOWN) + mark(stackTop, stackBottom); + else + mark(stackBottom, stackTop); + } + } -extern (C) size_t gc_reserve( size_t sz ) -{ - return _gc.reserve( sz ); -} + // Scan roots[] + debug(COLLECT_PRINTF) printf("scan roots[]\n"); + mark(roots, roots + nroots); -extern (C) void gc_free( void* p ) -{ - _gc.free( p ); -} + // Scan ranges[] + debug(COLLECT_PRINTF) printf("scan ranges[]\n"); + //log++; + for (n = 0; n < nranges; n++) + { + debug(COLLECT_PRINTF) printf("\t%x .. %x\n", ranges[n].pbot, ranges[n].ptop); + mark(ranges[n].pbot, ranges[n].ptop); + } + //log--; -extern (C) void* gc_addrOf( void* p ) -{ - return _gc.addrOf( p ); -} + debug(COLLECT_PRINTF) printf("\tscan heap\n"); + while (anychanges) + { + anychanges = 0; + for (n = 0; n < npools; n++) + { + uint *bbase; + uint *b; + uint *btop; -extern (C) size_t gc_sizeOf( void* p ) -{ - return _gc.sizeOf( p ); -} + pool = pooltable[n]; -extern (C) BlkInfo gc_query( void* p ) -{ - return _gc.query( p ); -} + bbase = pool.scan.base(); + btop = bbase + pool.scan.nwords; + for (b = bbase; b < btop;) + { Bins bin; + size_t pn; + size_t u; + size_t bitm; + byte* o; -// NOTE: This routine is experimental. The stats or function name may change -// before it is made officially available. -extern (C) GCStats gc_stats() -{ - GCStats stats = void; - _gc.getStats( stats ); - return stats; -} + bitm = *b; + if (!bitm) + { b++; + continue; + } + *b = 0; -extern (C) void gc_addRoot( void* p ) -{ - _gc.addRoot( p ); + o = pool.baseAddr + (b - bbase) * 32 * 16; + if (!(bitm & 0xFFFF)) + { + bitm >>= 16; + o += 16 * 16; + } + for (; bitm; o += 16, bitm >>= 1) + { + if (!(bitm & 1)) + continue; + + pn = cast(size_t)(o - pool.baseAddr) / PAGESIZE; + bin = cast(Bins)pool.pagetable[pn]; + if (bin < B_PAGE) + { + mark(o, o + binsize[bin]); + } + else if (bin == B_PAGE || bin == B_PAGEPLUS) + { + if (bin == B_PAGEPLUS) + { + while (pool.pagetable[pn - 1] != B_PAGE) + pn--; + } + u = 1; + while (pn + u < pool.ncommitted && pool.pagetable[pn + u] == B_PAGEPLUS) + u++; + mark(o, o + u * PAGESIZE); + } + } + } + } + } + + thread_resumeAll(); + + // Free up everything not marked + debug(COLLECT_PRINTF) printf("\tfree'ing\n"); + size_t freedpages = 0; + size_t freed = 0; + for (n = 0; n < npools; n++) + { size_t pn; + size_t ncommitted; + uint* bbase; + + pool = pooltable[n]; + bbase = pool.mark.base(); + ncommitted = pool.ncommitted; + for (pn = 0; pn < ncommitted; pn++, bbase += PAGESIZE / (32 * 16)) + { + Bins bin = cast(Bins)pool.pagetable[pn]; + + if (bin < B_PAGE) + { byte* p; + byte* ptop; + size_t biti; + size_t bitstride; + auto size = binsize[bin]; + + p = pool.baseAddr + pn * PAGESIZE; + ptop = p + PAGESIZE; + biti = pn * (PAGESIZE/16); + bitstride = size / 16; + + version(none) // BUG: doesn't work because freebits() must also be cleared + { + // If free'd entire page + if (bbase[0] == 0 && bbase[1] == 0 && bbase[2] == 0 && bbase[3] == 0 && + bbase[4] == 0 && bbase[5] == 0 && bbase[6] == 0 && bbase[7] == 0) + { + for (; p < ptop; p += size, biti += bitstride) + { + if (pool.finals.nbits && pool.finals.testClear(biti)) + rt_finalize(cast(List *)sentinel_add(p), false/*noStack > 0*/); + gcx.clrBits(pool, biti, BlkAttr.ALL_BITS); + + List *list = cast(List *)p; + //debug(PRINTF) printf("\tcollecting %x\n", list); + log_free(sentinel_add(list)); + + debug (MEMSTOMP) cstring.memset(p, 0xF3, size); + } + pool.pagetable[pn] = B_FREE; + freed += PAGESIZE; + //debug(PRINTF) printf("freeing entire page %d\n", pn); + continue; + } + } + for (; p < ptop; p += size, biti += bitstride) + { + if (!pool.mark.test(biti)) + { + sentinel_Invariant(sentinel_add(p)); + + pool.freebits.set(biti); + if (pool.finals.nbits && pool.finals.testClear(biti)) + rt_finalize(cast(List *)sentinel_add(p), false/*noStack > 0*/); + clrBits(pool, biti, BlkAttr.ALL_BITS); + + List *list = cast(List *)p; + debug(PRINTF) printf("\tcollecting %x\n", list); + log_free(sentinel_add(list)); + + debug (MEMSTOMP) cstring.memset(p, 0xF3, size); + + freed += size; + } + } + } + else if (bin == B_PAGE) + { size_t biti = pn * (PAGESIZE / 16); + + if (!pool.mark.test(biti)) + { byte *p = pool.baseAddr + pn * PAGESIZE; + + sentinel_Invariant(sentinel_add(p)); + if (pool.finals.nbits && pool.finals.testClear(biti)) + rt_finalize(sentinel_add(p), false/*noStack > 0*/); + clrBits(pool, biti, BlkAttr.ALL_BITS); + + debug(COLLECT_PRINTF) printf("\tcollecting big %x\n", p); + log_free(sentinel_add(p)); + pool.pagetable[pn] = B_FREE; + freedpages++; + debug (MEMSTOMP) cstring.memset(p, 0xF3, PAGESIZE); + while (pn + 1 < ncommitted && pool.pagetable[pn + 1] == B_PAGEPLUS) + { + pn++; + pool.pagetable[pn] = B_FREE; + freedpages++; + + debug (MEMSTOMP) + { p += PAGESIZE; + cstring.memset(p, 0xF3, PAGESIZE); + } + } + } + } + } + } + + // Zero buckets + bucket[] = null; + + // Free complete pages, rebuild free list + debug(COLLECT_PRINTF) printf("\tfree complete pages\n"); + size_t recoveredpages = 0; + for (n = 0; n < npools; n++) + { size_t pn; + size_t ncommitted; + + pool = pooltable[n]; + ncommitted = pool.ncommitted; + for (pn = 0; pn < ncommitted; pn++) + { + Bins bin = cast(Bins)pool.pagetable[pn]; + size_t biti; + size_t u; + + if (bin < B_PAGE) + { + size_t size = binsize[bin]; + size_t bitstride = size / 16; + size_t bitbase = pn * (PAGESIZE / 16); + size_t bittop = bitbase + (PAGESIZE / 16); + byte* p; + + biti = bitbase; + for (biti = bitbase; biti < bittop; biti += bitstride) + { if (!pool.freebits.test(biti)) + goto Lnotfree; + } + pool.pagetable[pn] = B_FREE; + recoveredpages++; + continue; + + Lnotfree: + p = pool.baseAddr + pn * PAGESIZE; + for (u = 0; u < PAGESIZE; u += size) + { biti = bitbase + u / 16; + if (pool.freebits.test(biti)) + { List *list; + + list = cast(List *)(p + u); + if (list.next != bucket[bin]) // avoid unnecessary writes + list.next = bucket[bin]; + bucket[bin] = list; + } + } + } + } + } + + debug(COLLECT_PRINTF) printf("recovered pages = %d\n", recoveredpages); + debug(COLLECT_PRINTF) printf("\tfree'd %u bytes, %u pages from %u pools\n", freed, freedpages, npools); + + return freedpages + recoveredpages; + } + + + /** + * + */ + uint getBits(Pool* pool, size_t biti) + in + { + assert( pool ); + } + body + { + uint bits; + + if (pool.finals.nbits && + pool.finals.test(biti)) + bits |= BlkAttr.FINALIZE; + if (pool.noscan.test(biti)) + bits |= BlkAttr.NO_SCAN; +// if (pool.nomove.nbits && +// pool.nomove.test(biti)) +// bits |= BlkAttr.NO_MOVE; + return bits; + } + + + /** + * + */ + void setBits(Pool* pool, size_t biti, uint mask) + in + { + assert( pool ); + } + body + { + if (mask & BlkAttr.FINALIZE) + { + if (!pool.finals.nbits) + pool.finals.alloc(pool.mark.nbits); + pool.finals.set(biti); + } + if (mask & BlkAttr.NO_SCAN) + { + pool.noscan.set(biti); + } +// if (mask & BlkAttr.NO_MOVE) +// { +// if (!pool.nomove.nbits) +// pool.nomove.alloc(pool.mark.nbits); +// pool.nomove.set(biti); +// } + } + + + /** + * + */ + void clrBits(Pool* pool, size_t biti, uint mask) + in + { + assert( pool ); + } + body + { + if (mask & BlkAttr.FINALIZE && pool.finals.nbits) + pool.finals.clear(biti); + if (mask & BlkAttr.NO_SCAN) + pool.noscan.clear(biti); +// if (mask & BlkAttr.NO_MOVE && pool.nomove.nbits) +// pool.nomove.clear(biti); + } + + + /***** Leak Detector ******/ + + + debug (LOGGING) + { + LogArray current; + LogArray prev; + + + void log_init() + { + //debug(PRINTF) printf("+log_init()\n"); + current.reserve(1000); + prev.reserve(1000); + //debug(PRINTF) printf("-log_init()\n"); + } + + + void log_malloc(void *p, size_t size) + { + //debug(PRINTF) printf("+log_malloc(p = %x, size = %d)\n", p, size); + Log log; + + log.p = p; + log.size = size; + log.line = GC.line; + log.file = GC.file; + log.parent = null; + + GC.line = 0; + GC.file = null; + + current.push(log); + //debug(PRINTF) printf("-log_malloc()\n"); + } + + + void log_free(void *p) + { + //debug(PRINTF) printf("+log_free(%x)\n", p); + size_t i; + + i = current.find(p); + if (i == OPFAIL) + { + debug(PRINTF) printf("free'ing unallocated memory %x\n", p); + } + else + current.remove(i); + //debug(PRINTF) printf("-log_free()\n"); + } + + + void log_collect() + { + //debug(PRINTF) printf("+log_collect()\n"); + // Print everything in current that is not in prev + + debug(PRINTF) printf("New pointers this cycle: --------------------------------\n"); + size_t used = 0; + for (size_t i = 0; i < current.dim; i++) + { + size_t j; + + j = prev.find(current.data[i].p); + if (j == OPFAIL) + current.data[i].print(); + else + used++; + } + + debug(PRINTF) printf("All roots this cycle: --------------------------------\n"); + for (size_t i = 0; i < current.dim; i++) + { + void *p; + size_t j; + + p = current.data[i].p; + if (!findPool(current.data[i].parent)) + { + j = prev.find(current.data[i].p); + if (j == OPFAIL) + debug(PRINTF) printf("N"); + else + debug(PRINTF) printf(" ");; + current.data[i].print(); + } + } + + debug(PRINTF) printf("Used = %d-------------------------------------------------\n", used); + prev.copy(¤t); + + debug(PRINTF) printf("-log_collect()\n"); + } + + + void log_parent(void *p, void *parent) + { + //debug(PRINTF) printf("+log_parent()\n"); + size_t i; + + i = current.find(p); + if (i == OPFAIL) + { + debug(PRINTF) printf("parent'ing unallocated memory %x, parent = %x\n", p, parent); + Pool *pool; + pool = findPool(p); + assert(pool); + size_t offset = cast(size_t)(p - pool.baseAddr); + size_t biti; + size_t pn = offset / PAGESIZE; + Bins bin = cast(Bins)pool.pagetable[pn]; + biti = (offset & notbinsize[bin]); + debug(PRINTF) printf("\tbin = %d, offset = x%x, biti = x%x\n", bin, offset, biti); + } + else + { + current.data[i].parent = parent; + } + //debug(PRINTF) printf("-log_parent()\n"); + } + + } + else + { + void log_init() { } + void log_malloc(void *p, size_t size) { } + void log_free(void *p) { } + void log_collect() { } + void log_parent(void *p, void *parent) { } + } } -extern (C) void gc_addRange( void* p, size_t sz ) + +/* ============================ Pool =============================== */ + + +struct Pool { - _gc.addRange( p, sz ); + byte* baseAddr; + byte* topAddr; + GCBits mark; // entries already scanned, or should not be scanned + GCBits scan; // entries that need to be scanned + GCBits freebits; // entries that are on the free list + GCBits finals; // entries that need finalizer run on them + GCBits noscan; // entries that should not be scanned + + size_t npages; + size_t ncommitted; // ncommitted <= npages + ubyte* pagetable; + + + void initialize(size_t npages) + { + size_t poolsize; + + //debug(PRINTF) printf("Pool::Pool(%u)\n", npages); + poolsize = npages * PAGESIZE; + assert(poolsize >= POOLSIZE); + baseAddr = cast(byte *)os_mem_map(poolsize); + + // Some of the code depends on page alignment of memory pools + assert((cast(size_t)baseAddr & (PAGESIZE - 1)) == 0); + + if (!baseAddr) + { + //debug(PRINTF) printf("GC fail: poolsize = x%x, errno = %d\n", poolsize, errno); + //debug(PRINTF) printf("message = '%s'\n", sys_errlist[errno]); + + npages = 0; + poolsize = 0; + } + //assert(baseAddr); + topAddr = baseAddr + poolsize; + + mark.alloc(cast(size_t)poolsize / 16); + scan.alloc(cast(size_t)poolsize / 16); + freebits.alloc(cast(size_t)poolsize / 16); + noscan.alloc(cast(size_t)poolsize / 16); + + pagetable = cast(ubyte*)cstdlib.malloc(npages); + if (!pagetable) + onOutOfMemoryError(); + cstring.memset(pagetable, B_UNCOMMITTED, npages); + + this.npages = npages; + ncommitted = 0; + } + + + void Dtor() + { + if (baseAddr) + { + int result; + + if (ncommitted) + { + result = os_mem_decommit(baseAddr, 0, ncommitted * PAGESIZE); + assert(result == 0); + ncommitted = 0; + } + + if (npages) + { + result = os_mem_unmap(baseAddr, npages * PAGESIZE); + assert(result == 0); + npages = 0; + } + + baseAddr = null; + topAddr = null; + } + if (pagetable) + cstdlib.free(pagetable); + + mark.Dtor(); + scan.Dtor(); + freebits.Dtor(); + finals.Dtor(); + noscan.Dtor(); + } + + + void Invariant() { } + + + invariant + { + //mark.Invariant(); + //scan.Invariant(); + //freebits.Invariant(); + //finals.Invariant(); + //noscan.Invariant(); + + if (baseAddr) + { + //if (baseAddr + npages * PAGESIZE != topAddr) + //printf("baseAddr = %p, npages = %d, topAddr = %p\n", baseAddr, npages, topAddr); + assert(baseAddr + npages * PAGESIZE == topAddr); + assert(ncommitted <= npages); + } + + for (size_t i = 0; i < npages; i++) + { Bins bin = cast(Bins)pagetable[i]; + + assert(bin < B_MAX); + } + } + + + /** + * Allocate n pages from Pool. + * Returns OPFAIL on failure. + */ + size_t allocPages(size_t n) + { + size_t i; + size_t n2; + + //debug(PRINTF) printf("Pool::allocPages(n = %d)\n", n); + n2 = n; + for (i = 0; i < ncommitted; i++) + { + if (pagetable[i] == B_FREE) + { + if (--n2 == 0) + { //debug(PRINTF) printf("\texisting pn = %d\n", i - n + 1); + return i - n + 1; + } + } + else + n2 = n; + } + return extendPages(n); + } + + /** + * Extend Pool by n pages. + * Returns OPFAIL on failure. + */ + size_t extendPages(size_t n) + { + //debug(PRINTF) printf("Pool::extendPages(n = %d)\n", n); + if (ncommitted + n <= npages) + { + size_t tocommit; + + tocommit = (n + (COMMITSIZE/PAGESIZE) - 1) & ~(COMMITSIZE/PAGESIZE - 1); + if (ncommitted + tocommit > npages) + tocommit = npages - ncommitted; + //debug(PRINTF) printf("\tlooking to commit %d more pages\n", tocommit); + //fflush(stdout); + if (os_mem_commit(baseAddr, ncommitted * PAGESIZE, tocommit * PAGESIZE) == 0) + { + cstring.memset(pagetable + ncommitted, B_FREE, tocommit); + auto i = ncommitted; + ncommitted += tocommit; + + while (i && pagetable[i - 1] == B_FREE) + i--; + + return i; + } + //debug(PRINTF) printf("\tfailed to commit %d pages\n", tocommit); + } + + return OPFAIL; + } + + + /** + * Free npages pages starting with pagenum. + */ + void freePages(size_t pagenum, size_t npages) + { + cstring.memset(&pagetable[pagenum], B_FREE, npages); + } + + + /** + * Used for sorting pooltable[] + */ + int opCmp(Pool *p2) + { + if (baseAddr < p2.baseAddr) + return -1; + else + return cast(int)(baseAddr > p2.baseAddr); + } } -extern (C) void gc_removeRoot( void *p ) + +/* ============================ SENTINEL =============================== */ + + +version (SENTINEL) { - _gc.removeRoot( p ); -} + const size_t SENTINEL_PRE = cast(size_t) 0xF4F4F4F4F4F4F4F4UL; // 32 or 64 bits + const ubyte SENTINEL_POST = 0xF5; // 8 bits + const uint SENTINEL_EXTRA = 2 * size_t.sizeof + 1; + + + size_t* sentinel_size(void *p) { return &(cast(size_t *)p)[-2]; } + size_t* sentinel_pre(void *p) { return &(cast(size_t *)p)[-1]; } + ubyte* sentinel_post(void *p) { return &(cast(ubyte *)p)[*sentinel_size(p)]; } + + + void sentinel_init(void *p, size_t size) + { + *sentinel_size(p) = size; + *sentinel_pre(p) = SENTINEL_PRE; + *sentinel_post(p) = SENTINEL_POST; + } + + + void sentinel_Invariant(void *p) + { + assert(*sentinel_pre(p) == SENTINEL_PRE); + assert(*sentinel_post(p) == SENTINEL_POST); + } + + + void *sentinel_add(void *p) + { + return p + 2 * size_t.sizeof; + } -extern (C) void gc_removeRange( void *p ) + + void *sentinel_sub(void *p) + { + return p - 2 * size_t.sizeof; + } +} +else { - _gc.removeRange( p ); + const uint SENTINEL_EXTRA = 0; + + + void sentinel_init(void *p, size_t size) + { + } + + + void sentinel_Invariant(void *p) + { + } + + + void *sentinel_add(void *p) + { + return p; + } + + + void *sentinel_sub(void *p) + { + return p; + } } +