X-Git-Url: https://git.hcoop.net/bpt/guile.git/blobdiff_plain/960c408c04470b0680e250b44e5273987e1aa66d..41a2772c5c234407c991f97ce08e34fba372e6c5:/libguile/gc-malloc.c diff --git a/libguile/gc-malloc.c b/libguile/gc-malloc.c index b2c73a104..cdc985e37 100644 --- a/libguile/gc-malloc.c +++ b/libguile/gc-malloc.c @@ -1,46 +1,26 @@ -/* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002 Free Software Foundation, Inc. +/* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002, 2003, 2004, 2006, 2008 Free Software Foundation, Inc. * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2, or (at your option) - * any later version. + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. * - * This program is distributed in the hope that it will be useful, + * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. * - * You should have received a copy of the GNU General Public License - * along with this software; see the file COPYING. If not, write to - * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, - * Boston, MA 02111-1307 USA - * - * As a special exception, the Free Software Foundation gives permission - * for additional uses of the text contained in its release of GUILE. - * - * The exception is that, if you link the GUILE library with other files - * to produce an executable, this does not by itself cause the - * resulting executable to be covered by the GNU General Public License. - * Your use of that executable is in no way restricted on account of - * linking the GUILE library code into it. - * - * This exception does not however invalidate any other reasons why - * the executable file might be covered by the GNU General Public License. - * - * This exception applies only to the code released by the - * Free Software Foundation under the name GUILE. If you copy - * code from other Free Software Foundation releases into a copy of - * GUILE, as the General Public License permits, the exception does - * not apply to the code that you add in this way. To avoid misleading - * anyone as to the status of such modified files, you must delete - * this exception notice from them. - * - * If you write modifications of your own for GUILE, it is your choice - * whether to permit this exception to apply to your modifications. - * If you do not wish that, delete this exception notice. */ + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ +#ifdef HAVE_CONFIG_H +# include +#endif + #include #include #include @@ -99,21 +79,13 @@ extern unsigned long * __libc_ia64_register_backing_store_base; static int scm_i_minyield_malloc; -static scm_t_mutex malloc_mutex; - -void -scm_gc_malloc_prehistory () -{ - scm_i_plugin_mutex_init (&malloc_mutex, 0); -} - void scm_gc_init_malloc (void) { scm_mtrigger = scm_getenv_int ("GUILE_INIT_MALLOC_LIMIT", SCM_DEFAULT_INIT_MALLOC_LIMIT); - scm_i_minyield_malloc = scm_getenv_int ("GUILE_MIN_YIELD_MALLOC", - SCM_DEFAULT_MALLOC_MINYIELD); + scm_i_minyield_malloc = scm_getenv_int ("GUILE_MIN_YIELD_MALLOC", + SCM_DEFAULT_MALLOC_MINYIELD); if (scm_i_minyield_malloc >= 100) scm_i_minyield_malloc = 99; @@ -134,33 +106,28 @@ scm_realloc (void *mem, size_t size) { void *ptr; - scm_i_plugin_mutex_lock (&malloc_mutex); SCM_SYSCALL (ptr = realloc (mem, size)); - scm_i_plugin_mutex_unlock (&malloc_mutex); if (ptr) return ptr; - scm_i_thread_put_to_sleep (); - - scm_i_sweep_all_segments ("realloc"); - - scm_i_plugin_mutex_lock (&malloc_mutex); - SCM_SYSCALL (ptr = realloc (mem, size)); - scm_i_plugin_mutex_unlock (&malloc_mutex); - if (ptr) - { - scm_i_thread_wake_up (); - return ptr; - } + scm_i_scm_pthread_mutex_lock (&scm_i_sweep_mutex); + scm_gc_running_p = 1; - scm_igc ("realloc"); - scm_i_sweep_all_segments ("realloc"); - - scm_i_thread_wake_up (); + scm_i_gc ("realloc"); + + /* + We don't want these sweep statistics to influence results for + cell GC, so we don't collect statistics. + + realloc () failed, so we're really desparate to free memory. Run a + full sweep. + */ + scm_i_sweep_all_segments ("realloc", NULL); + + scm_gc_running_p = 0; + scm_i_pthread_mutex_unlock (&scm_i_sweep_mutex); - scm_i_plugin_mutex_lock (&malloc_mutex); SCM_SYSCALL (ptr = realloc (mem, size)); - scm_i_plugin_mutex_unlock (&malloc_mutex); if (ptr) return ptr; @@ -186,9 +153,7 @@ scm_calloc (size_t sz) By default, try to use calloc, as it is likely more efficient than calling memset by hand. */ - scm_i_plugin_mutex_lock (&malloc_mutex); - SCM_SYSCALL(ptr= calloc (sz, 1)); - scm_i_plugin_mutex_unlock (&malloc_mutex); + SCM_SYSCALL (ptr = calloc (sz, 1)); if (ptr) return ptr; @@ -201,7 +166,7 @@ scm_calloc (size_t sz) char * scm_strndup (const char *str, size_t n) { - char *dst = scm_malloc (n+1); + char *dst = scm_malloc (n + 1); memcpy (dst, str, n); dst[n] = 0; return dst; @@ -213,15 +178,45 @@ scm_strdup (const char *str) return scm_strndup (str, strlen (str)); } -void -scm_gc_register_collectable_memory (void *mem, size_t size, const char *what) +static void +decrease_mtrigger (size_t size, const char * what) { - scm_mallocated += size; + scm_i_pthread_mutex_lock (&scm_i_gc_admin_mutex); - /* - we could finish the full sweep (without mark) here, but in - practice this turns out to be ineffective. - */ + if (size > scm_mallocated) + { + fprintf (stderr, "`scm_mallocated' underflow. This means that more " + "memory was unregistered\n" + "via `scm_gc_unregister_collectable_memory ()' than " + "registered.\n"); + abort (); + } + + scm_mallocated -= size; + scm_gc_malloc_collected += size; + scm_i_pthread_mutex_unlock (&scm_i_gc_admin_mutex); +} + +static void +increase_mtrigger (size_t size, const char *what) +{ + size_t mallocated = 0; + int overflow = 0, triggered = 0; + + scm_i_pthread_mutex_lock (&scm_i_gc_admin_mutex); + if (ULONG_MAX - size < scm_mallocated) + overflow = 1; + else + { + scm_mallocated += size; + mallocated = scm_mallocated; + if (scm_mallocated > scm_mtrigger) + triggered = 1; + } + scm_i_pthread_mutex_unlock (&scm_i_gc_admin_mutex); + + if (overflow) + scm_memory_error ("Overflow of scm_mallocated: too much memory in use."); /* A program that uses a lot of malloced collectable memory (vectors, @@ -229,25 +224,33 @@ scm_gc_register_collectable_memory (void *mem, size_t size, const char *what) do GC more often (before cells are exhausted), otherwise swapping and malloc management will tie it down. */ - if (scm_mallocated > scm_mtrigger) + if (triggered) { unsigned long prev_alloced; float yield; + + scm_i_scm_pthread_mutex_lock (&scm_i_sweep_mutex); + scm_gc_running_p = 1; - scm_i_thread_put_to_sleep (); - - prev_alloced = scm_mallocated; - scm_igc (what); - scm_i_sweep_all_segments ("mtrigger"); + prev_alloced = mallocated; + + /* The GC will finish the pending sweep. For that reason, we + don't execute a complete sweep after GC, although that might + free some more memory. + */ + scm_i_gc (what); - yield = ((float)prev_alloced - (float) scm_mallocated) - / (float) prev_alloced; + yield = (((float) prev_alloced - (float) scm_mallocated) + / (float) prev_alloced); - scm_gc_malloc_yield_percentage = (int) (100 * yield); + scm_gc_malloc_yield_percentage = (int) (100 * yield); #ifdef DEBUGINFO fprintf (stderr, "prev %lud , now %lud, yield %4.2lf, want %d", - prev_alloced, scm_mallocated, 100.0*yield, scm_i_minyield_malloc); + prev_alloced, + scm_mallocated, + 100.0 * yield, + scm_i_minyield_malloc); #endif if (yield < scm_i_minyield_malloc / 100.0) @@ -263,28 +266,39 @@ scm_gc_register_collectable_memory (void *mem, size_t size, const char *what) float no_overflow_trigger = scm_mallocated * 110.0; no_overflow_trigger /= (float) (100.0 - scm_i_minyield_malloc); - scm_mtrigger = (unsigned long) no_overflow_trigger; + + + if (no_overflow_trigger >= (float) ULONG_MAX) + scm_mtrigger = ULONG_MAX; + else + scm_mtrigger = (unsigned long) no_overflow_trigger; #ifdef DEBUGINFO - fprintf (stderr, "Mtrigger sweep: ineffective. New trigger %d\n", scm_mtrigger); + fprintf (stderr, "Mtrigger sweep: ineffective. New trigger %d\n", + scm_mtrigger); #endif } - - scm_i_thread_wake_up (); + + scm_gc_running_p = 0; + scm_i_pthread_mutex_unlock (&scm_i_sweep_mutex); } - +} + +void +scm_gc_register_collectable_memory (void *mem, size_t size, const char *what) +{ + increase_mtrigger (size, what); #ifdef GUILE_DEBUG_MALLOC if (mem) scm_malloc_register (mem, what); #endif } + void scm_gc_unregister_collectable_memory (void *mem, size_t size, const char *what) { - scm_mallocated -= size; - scm_gc_malloc_collected += size; - + decrease_mtrigger (size, what); #ifdef GUILE_DEBUG_MALLOC if (mem) scm_malloc_unregister (mem); @@ -300,13 +314,12 @@ scm_gc_malloc (size_t size, const char *what) again in scm_gc_register_collectable_memory. We don't really want the second GC since it will not find new garbage. - - Note: this is a theoretical peeve. In reality, malloc() never + Note: this is a theoretical peeve. In reality, malloc () never returns NULL. Usually, memory is overcommitted, and when you try to write it the program is killed with signal 11. --hwn */ - void *ptr = scm_malloc (size); + void *ptr = size ? scm_malloc (size) : NULL; scm_gc_register_collectable_memory (ptr, size, what); return ptr; } @@ -323,11 +336,28 @@ scm_gc_calloc (size_t size, const char *what) void * scm_gc_realloc (void *mem, size_t old_size, size_t new_size, const char *what) { + void *ptr; + /* XXX - see scm_gc_malloc. */ - void *ptr = scm_realloc (mem, new_size); - scm_gc_unregister_collectable_memory (mem, old_size, what); - scm_gc_register_collectable_memory (ptr, new_size, what); + + /* + scm_realloc () may invalidate the block pointed to by WHERE, eg. by + unmapping it from memory or altering the contents. Since + increase_mtrigger () might trigger a GC that would scan + MEM, it is crucial that this call precedes realloc (). + */ + + decrease_mtrigger (old_size, what); + increase_mtrigger (new_size, what); + + ptr = scm_realloc (mem, new_size); + +#ifdef GUILE_DEBUG_MALLOC + if (mem) + scm_malloc_reregister (mem, ptr, what); +#endif + return ptr; } @@ -335,7 +365,8 @@ void scm_gc_free (void *mem, size_t size, const char *what) { scm_gc_unregister_collectable_memory (mem, size, what); - free (mem); + if (mem) + free (mem); } char * @@ -446,7 +477,10 @@ scm_done_malloc (long size) ("scm_done_malloc is deprecated. " "Use scm_gc_register_collectable_memory instead."); - scm_gc_register_collectable_memory (NULL, size, "foreign mallocs"); + if (size >= 0) + scm_gc_register_collectable_memory (NULL, size, "foreign mallocs"); + else + scm_gc_unregister_collectable_memory (NULL, -size, "foreign mallocs"); } void @@ -456,7 +490,10 @@ scm_done_free (long size) ("scm_done_free is deprecated. " "Use scm_gc_unregister_collectable_memory instead."); - scm_gc_unregister_collectable_memory (NULL, size, "foreign mallocs"); + if (size >= 0) + scm_gc_unregister_collectable_memory (NULL, size, "foreign mallocs"); + else + scm_gc_register_collectable_memory (NULL, -size, "foreign mallocs"); } #endif /* SCM_ENABLE_DEPRECATED == 1 */