/* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002, 2003, 2004, 2006, 2008 Free Software Foundation, Inc. * * 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 3 of * the License, or (at your option) any later version. * * 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 * Lesser General Public License for more details. * * 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 #ifdef __ia64__ #include extern unsigned long * __libc_ia64_register_backing_store_base; #endif #include "libguile/_scm.h" #include "libguile/eval.h" #include "libguile/stime.h" #include "libguile/stackchk.h" #include "libguile/struct.h" #include "libguile/smob.h" #include "libguile/unif.h" #include "libguile/async.h" #include "libguile/ports.h" #include "libguile/root.h" #include "libguile/strings.h" #include "libguile/vectors.h" #include "libguile/weaks.h" #include "libguile/hashtab.h" #include "libguile/tags.h" #include "libguile/validate.h" #include "libguile/deprecation.h" #include "libguile/gc.h" #include "libguile/private-gc.h" #ifdef GUILE_DEBUG_MALLOC #include "libguile/debug-malloc.h" #endif #ifdef HAVE_MALLOC_H #include #endif #ifdef HAVE_UNISTD_H #include #endif /* INIT_MALLOC_LIMIT is the initial amount of malloc usage which will trigger a GC. After startup (at the guile> prompt), we have approximately 100k of alloced memory, which won't go away on GC. Let's set the init such that we get a nice yield on the next allocation: */ #define SCM_DEFAULT_INIT_MALLOC_LIMIT 200*1024 #define SCM_DEFAULT_MALLOC_MINYIELD 40 /* #define DEBUGINFO */ static int scm_i_minyield_malloc; 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); if (scm_i_minyield_malloc >= 100) scm_i_minyield_malloc = 99; if (scm_i_minyield_malloc < 1) scm_i_minyield_malloc = 1; if (scm_mtrigger < 0) scm_mtrigger = SCM_DEFAULT_INIT_MALLOC_LIMIT; } /* Function for non-cell memory management. */ void * scm_realloc (void *mem, size_t size) { void *ptr; SCM_SYSCALL (ptr = realloc (mem, size)); if (ptr) return ptr; scm_i_scm_pthread_mutex_lock (&scm_i_sweep_mutex); scm_gc_running_p = 1; 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_SYSCALL (ptr = realloc (mem, size)); if (ptr) return ptr; scm_memory_error ("realloc"); } void * scm_malloc (size_t sz) { return scm_realloc (NULL, sz); } /* Hmm. Should we use the C convention for arguments (i.e. N_ELTS, SIZEOF_ELT)? --hwn */ void * scm_calloc (size_t sz) { void * ptr; /* By default, try to use calloc, as it is likely more efficient than calling memset by hand. */ SCM_SYSCALL (ptr = calloc (sz, 1)); if (ptr) return ptr; ptr = scm_realloc (NULL, sz); memset (ptr, 0x0, sz); return ptr; } char * scm_strndup (const char *str, size_t n) { char *dst = scm_malloc (n + 1); memcpy (dst, str, n); dst[n] = 0; return dst; } char * scm_strdup (const char *str) { return scm_strndup (str, strlen (str)); } static void decrease_mtrigger (size_t size, const char * what) { scm_i_pthread_mutex_lock (&scm_i_gc_admin_mutex); 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, strings), will use a lot of memory off the cell-heap; it needs to do GC more often (before cells are exhausted), otherwise swapping and malloc management will tie it down. */ if (triggered) { unsigned long prev_alloced; float yield; scm_i_scm_pthread_mutex_lock (&scm_i_sweep_mutex); scm_gc_running_p = 1; 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); 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); #endif if (yield < scm_i_minyield_malloc / 100.0) { /* We make the trigger a little larger, even; If you have a program that builds up a lot of data in strings, then the desired yield will never be satisfied. Instead of getting bogged down, we let the mtrigger grow strongly with it. */ float no_overflow_trigger = scm_mallocated * 110.0; no_overflow_trigger /= (float) (100.0 - scm_i_minyield_malloc); 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); #endif } 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) { decrease_mtrigger (size, what); #ifdef GUILE_DEBUG_MALLOC if (mem) scm_malloc_unregister (mem); #endif } void * scm_gc_malloc (size_t size, const char *what) { /* The straightforward implementation below has the problem that it might call the GC twice, once in scm_malloc and then 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 returns NULL. Usually, memory is overcommitted, and when you try to write it the program is killed with signal 11. --hwn */ void *ptr = size ? scm_malloc (size) : NULL; scm_gc_register_collectable_memory (ptr, size, what); return ptr; } void * scm_gc_calloc (size_t size, const char *what) { void *ptr = scm_gc_malloc (size, what); memset (ptr, 0x0, size); return ptr; } void * scm_gc_realloc (void *mem, size_t old_size, size_t new_size, const char *what) { void *ptr; /* XXX - see scm_gc_malloc. */ /* 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; } void scm_gc_free (void *mem, size_t size, const char *what) { scm_gc_unregister_collectable_memory (mem, size, what); if (mem) free (mem); } char * scm_gc_strndup (const char *str, size_t n, const char *what) { char *dst = scm_gc_malloc (n+1, what); memcpy (dst, str, n); dst[n] = 0; return dst; } char * scm_gc_strdup (const char *str, const char *what) { return scm_gc_strndup (str, strlen (str), what); } #if SCM_ENABLE_DEPRECATED == 1 /* {Deprecated front end to malloc} * * scm_must_malloc, scm_must_realloc, scm_must_free, scm_done_malloc, * scm_done_free * * These functions provide services comparable to malloc, realloc, and * free. They should be used when allocating memory that will be under * control of the garbage collector, i.e., if the memory may be freed * during garbage collection. * * They are deprecated because they weren't really used the way * outlined above, and making sure to return the right amount from * smob free routines was sometimes difficult when dealing with nested * data structures. We basically want everybody to review their code * and use the more symmetrical scm_gc_malloc/scm_gc_free functions * instead. In some cases, where scm_must_malloc has been used * incorrectly (i.e. for non-GC-able memory), use scm_malloc/free. */ void * scm_must_malloc (size_t size, const char *what) { scm_c_issue_deprecation_warning ("scm_must_malloc is deprecated. " "Use scm_gc_malloc and scm_gc_free instead."); return scm_gc_malloc (size, what); } void * scm_must_realloc (void *where, size_t old_size, size_t size, const char *what) { scm_c_issue_deprecation_warning ("scm_must_realloc is deprecated. " "Use scm_gc_realloc and scm_gc_free instead."); return scm_gc_realloc (where, old_size, size, what); } char * scm_must_strndup (const char *str, size_t length) { scm_c_issue_deprecation_warning ("scm_must_strndup is deprecated. " "Use scm_gc_strndup and scm_gc_free instead."); return scm_gc_strndup (str, length, "string"); } char * scm_must_strdup (const char *str) { scm_c_issue_deprecation_warning ("scm_must_strdup is deprecated. " "Use scm_gc_strdup and scm_gc_free instead."); return scm_gc_strdup (str, "string"); } void scm_must_free (void *obj) #define FUNC_NAME "scm_must_free" { scm_c_issue_deprecation_warning ("scm_must_free is deprecated. " "Use scm_gc_malloc and scm_gc_free instead."); #ifdef GUILE_DEBUG_MALLOC scm_malloc_unregister (obj); #endif if (obj) free (obj); else { fprintf (stderr,"freeing NULL pointer"); abort (); } } #undef FUNC_NAME void scm_done_malloc (long size) { scm_c_issue_deprecation_warning ("scm_done_malloc is deprecated. " "Use scm_gc_register_collectable_memory instead."); if (size >= 0) scm_gc_register_collectable_memory (NULL, size, "foreign mallocs"); else scm_gc_unregister_collectable_memory (NULL, -size, "foreign mallocs"); } void scm_done_free (long size) { scm_c_issue_deprecation_warning ("scm_done_free is deprecated. " "Use scm_gc_unregister_collectable_memory instead."); 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 */