--- /dev/null
+/*
+ * Copyright (c) 2000-2005 by Hewlett-Packard Company. All rights reserved.
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ */
+
+#include "private/gc_priv.h"
+
+#if defined(THREAD_LOCAL_ALLOC)
+
+#ifndef THREADS
+# error "invalid config - THREAD_LOCAL_ALLOC requires GC_THREADS"
+#endif
+
+#include "private/thread_local_alloc.h"
+
+#include <stdlib.h>
+
+#if defined(USE_COMPILER_TLS)
+ __thread
+#elif defined(USE_WIN32_COMPILER_TLS)
+ __declspec(thread)
+#endif
+GC_key_t GC_thread_key;
+
+static GC_bool keys_initialized;
+
+/* Return a single nonempty freelist fl to the global one pointed to */
+/* by gfl. */
+
+static void return_single_freelist(void *fl, void **gfl)
+{
+ void *q, **qptr;
+
+ if (*gfl == 0) {
+ *gfl = fl;
+ } else {
+ GC_ASSERT(GC_size(fl) == GC_size(*gfl));
+ /* Concatenate: */
+ qptr = &(obj_link(fl));
+ while ((word)(q = *qptr) >= HBLKSIZE)
+ qptr = &(obj_link(q));
+ GC_ASSERT(0 == q);
+ *qptr = *gfl;
+ *gfl = fl;
+ }
+}
+
+/* Recover the contents of the freelist array fl into the global one gfl.*/
+/* We hold the allocator lock. */
+static void return_freelists(void **fl, void **gfl)
+{
+ int i;
+
+ for (i = 1; i < TINY_FREELISTS; ++i) {
+ if ((word)(fl[i]) >= HBLKSIZE) {
+ return_single_freelist(fl[i], gfl+i);
+ }
+ /* Clear fl[i], since the thread structure may hang around. */
+ /* Do it in a way that is likely to trap if we access it. */
+ fl[i] = (ptr_t)HBLKSIZE;
+ }
+ /* The 0 granule freelist really contains 1 granule objects. */
+# ifdef GC_GCJ_SUPPORT
+ if (fl[0] == ERROR_FL) return;
+# endif
+ if ((word)(fl[0]) >= HBLKSIZE) {
+ return_single_freelist(fl[0], gfl+1);
+ }
+}
+
+/* Each thread structure must be initialized. */
+/* This call must be made from the new thread. */
+GC_INNER void GC_init_thread_local(GC_tlfs p)
+{
+ int i;
+
+ GC_ASSERT(I_HOLD_LOCK());
+ if (!keys_initialized) {
+ if (0 != GC_key_create(&GC_thread_key, 0)) {
+ ABORT("Failed to create key for local allocator");
+ }
+ keys_initialized = TRUE;
+ }
+ if (0 != GC_setspecific(GC_thread_key, p)) {
+ ABORT("Failed to set thread specific allocation pointers");
+ }
+ for (i = 1; i < TINY_FREELISTS; ++i) {
+ p -> ptrfree_freelists[i] = (void *)(word)1;
+ p -> normal_freelists[i] = (void *)(word)1;
+# ifdef GC_GCJ_SUPPORT
+ p -> gcj_freelists[i] = (void *)(word)1;
+# endif
+ }
+ /* Set up the size 0 free lists. */
+ /* We now handle most of them like regular free lists, to ensure */
+ /* That explicit deallocation works. However, allocation of a */
+ /* size 0 "gcj" object is always an error. */
+ p -> ptrfree_freelists[0] = (void *)(word)1;
+ p -> normal_freelists[0] = (void *)(word)1;
+# ifdef GC_GCJ_SUPPORT
+ p -> gcj_freelists[0] = ERROR_FL;
+# endif
+}
+
+/* We hold the allocator lock. */
+GC_INNER void GC_destroy_thread_local(GC_tlfs p)
+{
+ /* We currently only do this from the thread itself or from */
+ /* the fork handler for a child process. */
+# ifndef HANDLE_FORK
+ GC_ASSERT(GC_getspecific(GC_thread_key) == (void *)p);
+# endif
+ return_freelists(p -> ptrfree_freelists, GC_aobjfreelist);
+ return_freelists(p -> normal_freelists, GC_objfreelist);
+# ifdef GC_GCJ_SUPPORT
+ return_freelists(p -> gcj_freelists, (void **)GC_gcjobjfreelist);
+# endif
+}
+
+#ifdef GC_ASSERTIONS
+ /* Defined in pthread_support.c or win32_threads.c. */
+ GC_bool GC_is_thread_tsd_valid(void *tsd);
+#endif
+
+GC_API void * GC_CALL GC_malloc(size_t bytes)
+{
+ size_t granules = ROUNDED_UP_GRANULES(bytes);
+ void *tsd;
+ void *result;
+ void **tiny_fl;
+
+# if !defined(USE_PTHREAD_SPECIFIC) && !defined(USE_WIN32_SPECIFIC)
+ GC_key_t k = GC_thread_key;
+ if (EXPECT(0 == k, FALSE)) {
+ /* We haven't yet run GC_init_parallel. That means */
+ /* we also aren't locking, so this is fairly cheap. */
+ return GC_core_malloc(bytes);
+ }
+ tsd = GC_getspecific(k);
+# else
+ tsd = GC_getspecific(GC_thread_key);
+# endif
+# if !defined(USE_COMPILER_TLS) && !defined(USE_WIN32_COMPILER_TLS)
+ if (EXPECT(0 == tsd, FALSE)) {
+ return GC_core_malloc(bytes);
+ }
+# endif
+ GC_ASSERT(GC_is_initialized);
+
+ GC_ASSERT(GC_is_thread_tsd_valid(tsd));
+
+ tiny_fl = ((GC_tlfs)tsd) -> normal_freelists;
+ GC_FAST_MALLOC_GRANS(result, granules, tiny_fl, DIRECT_GRANULES,
+ NORMAL, GC_core_malloc(bytes), obj_link(result)=0);
+# ifdef LOG_ALLOCS
+ GC_err_printf("GC_malloc(%u) = %p : %u\n",
+ (unsigned)bytes, result, (unsigned)GC_gc_no);
+# endif
+ return result;
+}
+
+GC_API void * GC_CALL GC_malloc_atomic(size_t bytes)
+{
+ size_t granules = ROUNDED_UP_GRANULES(bytes);
+ void *tsd;
+ void *result;
+ void **tiny_fl;
+
+# if !defined(USE_PTHREAD_SPECIFIC) && !defined(USE_WIN32_SPECIFIC)
+ GC_key_t k = GC_thread_key;
+ if (EXPECT(0 == k, FALSE)) {
+ /* We haven't yet run GC_init_parallel. That means */
+ /* we also aren't locking, so this is fairly cheap. */
+ return GC_core_malloc_atomic(bytes);
+ }
+ tsd = GC_getspecific(k);
+# else
+ tsd = GC_getspecific(GC_thread_key);
+# endif
+# if !defined(USE_COMPILER_TLS) && !defined(USE_WIN32_COMPILER_TLS)
+ if (EXPECT(0 == tsd, FALSE)) {
+ return GC_core_malloc_atomic(bytes);
+ }
+# endif
+ GC_ASSERT(GC_is_initialized);
+ tiny_fl = ((GC_tlfs)tsd) -> ptrfree_freelists;
+ GC_FAST_MALLOC_GRANS(result, granules, tiny_fl, DIRECT_GRANULES, PTRFREE,
+ GC_core_malloc_atomic(bytes), (void)0 /* no init */);
+ return result;
+}
+
+#ifdef GC_GCJ_SUPPORT
+
+# include "atomic_ops.h" /* for AO_compiler_barrier() */
+
+# include "include/gc_gcj.h"
+
+/* Gcj-style allocation without locks is extremely tricky. The */
+/* fundamental issue is that we may end up marking a free list, which */
+/* has freelist links instead of "vtable" pointers. That is usually */
+/* OK, since the next object on the free list will be cleared, and */
+/* will thus be interpreted as containing a zero descriptor. That's */
+/* fine if the object has not yet been initialized. But there are */
+/* interesting potential races. */
+/* In the case of incremental collection, this seems hopeless, since */
+/* the marker may run asynchronously, and may pick up the pointer to */
+/* the next freelist entry (which it thinks is a vtable pointer), get */
+/* suspended for a while, and then see an allocated object instead */
+/* of the vtable. This may be avoidable with either a handshake with */
+/* the collector or, probably more easily, by moving the free list */
+/* links to the second word of each object. The latter isn't a */
+/* universal win, since on architecture like Itanium, nonzero offsets */
+/* are not necessarily free. And there may be cache fill order issues. */
+/* For now, we punt with incremental GC. This probably means that */
+/* incremental GC should be enabled before we fork a second thread. */
+/* Unlike the other thread local allocation calls, we assume that the */
+/* collector has been explicitly initialized. */
+GC_API void * GC_CALL GC_gcj_malloc(size_t bytes,
+ void * ptr_to_struct_containing_descr)
+{
+ if (GC_EXPECT(GC_incremental, 0)) {
+ return GC_core_gcj_malloc(bytes, ptr_to_struct_containing_descr);
+ } else {
+ size_t granules = ROUNDED_UP_GRANULES(bytes);
+ void *result;
+ void **tiny_fl = ((GC_tlfs)GC_getspecific(GC_thread_key))
+ -> gcj_freelists;
+ GC_ASSERT(GC_gcj_malloc_initialized);
+ GC_FAST_MALLOC_GRANS(result, granules, tiny_fl, DIRECT_GRANULES,
+ GC_gcj_kind,
+ GC_core_gcj_malloc(bytes,
+ ptr_to_struct_containing_descr),
+ {AO_compiler_barrier();
+ *(void **)result = ptr_to_struct_containing_descr;});
+ /* This forces the initialization of the "method ptr". */
+ /* This is necessary to ensure some very subtle properties */
+ /* required if a GC is run in the middle of such an allocation. */
+ /* Here we implicitly also assume atomicity for the free list. */
+ /* and method pointer assignments. */
+ /* We must update the freelist before we store the pointer. */
+ /* Otherwise a GC at this point would see a corrupted */
+ /* free list. */
+ /* A real memory barrier is not needed, since the */
+ /* action of stopping this thread will cause prior writes */
+ /* to complete. */
+ /* We assert that any concurrent marker will stop us. */
+ /* Thus it is impossible for a mark procedure to see the */
+ /* allocation of the next object, but to see this object */
+ /* still containing a free list pointer. Otherwise the */
+ /* marker, by misinterpreting the freelist link as a vtable */
+ /* pointer, might find a random "mark descriptor" in the next */
+ /* object. */
+ return result;
+ }
+}
+
+#endif /* GC_GCJ_SUPPORT */
+
+/* The thread support layer must arrange to mark thread-local */
+/* free lists explicitly, since the link field is often */
+/* invisible to the marker. It knows how to find all threads; */
+/* we take care of an individual thread freelist structure. */
+GC_INNER void GC_mark_thread_local_fls_for(GC_tlfs p)
+{
+ ptr_t q;
+ int j;
+
+ for (j = 0; j < TINY_FREELISTS; ++j) {
+ q = p -> ptrfree_freelists[j];
+ if ((word)q > HBLKSIZE) GC_set_fl_marks(q);
+ q = p -> normal_freelists[j];
+ if ((word)q > HBLKSIZE) GC_set_fl_marks(q);
+# ifdef GC_GCJ_SUPPORT
+ if (j > 0) {
+ q = p -> gcj_freelists[j];
+ if ((word)q > HBLKSIZE) GC_set_fl_marks(q);
+ }
+# endif /* GC_GCJ_SUPPORT */
+ }
+}
+
+#if defined(GC_ASSERTIONS)
+ /* Check that all thread-local free-lists in p are completely marked. */
+ void GC_check_tls_for(GC_tlfs p)
+ {
+ int j;
+
+ for (j = 1; j < TINY_FREELISTS; ++j) {
+ GC_check_fl_marks(&p->ptrfree_freelists[j]);
+ GC_check_fl_marks(&p->normal_freelists[j]);
+# ifdef GC_GCJ_SUPPORT
+ GC_check_fl_marks(&p->gcj_freelists[j]);
+# endif
+ }
+ }
+#endif /* GC_ASSERTIONS */
+
+#endif /* THREAD_LOCAL_ALLOC */
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