From b527294153be3b79563c82c66102adc0004736c0 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 15 Apr 2024 19:54:12 +0200 Subject: Adding upstream version 2.6.7+dfsg. Signed-off-by: Daniel Baumann --- servers/slapd/sl_malloc.c | 739 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 739 insertions(+) create mode 100644 servers/slapd/sl_malloc.c (limited to 'servers/slapd/sl_malloc.c') diff --git a/servers/slapd/sl_malloc.c b/servers/slapd/sl_malloc.c new file mode 100644 index 0000000..9765bc3 --- /dev/null +++ b/servers/slapd/sl_malloc.c @@ -0,0 +1,739 @@ +/* sl_malloc.c - malloc routines using a per-thread slab */ +/* $OpenLDAP$ */ +/* This work is part of OpenLDAP Software . + * + * Copyright 2003-2022 The OpenLDAP Foundation. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted only as authorized by the OpenLDAP + * Public License. + * + * A copy of this license is available in the file LICENSE in the + * top-level directory of the distribution or, alternatively, at + * . + */ + +#include "portable.h" + +#include +#include + +#include "slap.h" + +#ifdef USE_VALGRIND +/* Get debugging help from Valgrind */ +#include +#define VGMEMP_MARK(m,s) VALGRIND_MAKE_MEM_NOACCESS(m,s) +#define VGMEMP_CREATE(h,r,z) VALGRIND_CREATE_MEMPOOL(h,r,z) +#define VGMEMP_TRIM(h,a,s) VALGRIND_MEMPOOL_TRIM(h,a,s) +#define VGMEMP_ALLOC(h,a,s) VALGRIND_MEMPOOL_ALLOC(h,a,s) +#define VGMEMP_CHANGE(h,a,b,s) VALGRIND_MEMPOOL_CHANGE(h,a,b,s) +#else +#define VGMEMP_MARK(m,s) +#define VGMEMP_CREATE(h,r,z) +#define VGMEMP_TRIM(h,a,s) +#define VGMEMP_ALLOC(h,a,s) +#define VGMEMP_CHANGE(h,a,b,s) +#endif + +/* + * This allocator returns temporary memory from a slab in a given memory + * context, aligned on a 2-int boundary. It cannot be used for data + * which will outlive the task allocating it. + * + * A new memory context attaches to the creator's thread context, if any. + * Threads cannot use other threads' memory contexts; there are no locks. + * + * The caller of slap_sl_malloc, usually a thread pool task, must + * slap_sl_free the memory before finishing: New tasks reuse the context + * and normally reset it, reclaiming memory left over from last task. + * + * The allocator helps memory fragmentation, speed and memory leaks. + * It is not (yet) reliable as a garbage collector: + * + * It falls back to context NULL - plain ber_memalloc() - when the + * context's slab is full. A reset does not reclaim such memory. + * Conversely, free/realloc of data not from the given context assumes + * context NULL. The data must not belong to another memory context. + * + * Code which has lost track of the current memory context can try + * slap_sl_context() or ch_malloc.c:ch_free/ch_realloc(). + * + * Allocations cannot yet return failure. Like ch_malloc, they succeed + * or abort slapd. This will change, do fix code which assumes success. + */ + +/* + * The stack-based allocator stores (ber_len_t)sizeof(head+block) at + * allocated blocks' head - and in freed blocks also at the tail, marked + * by ORing *next* block's head with 1. Freed blocks are only reclaimed + * from the last block forward. This is fast, but when a block is never + * freed, older blocks will not be reclaimed until the slab is reset... + */ + +#ifdef SLAP_NO_SL_MALLOC /* Useful with memory debuggers like Valgrind */ +enum { No_sl_malloc = 1 }; +#else +enum { No_sl_malloc = 0 }; +#endif + +#define SLAP_SLAB_SOBLOCK 64 + +struct slab_object { + void *so_ptr; + int so_blockhead; + LDAP_LIST_ENTRY(slab_object) so_link; +}; + +struct slab_heap { + void *sh_base; + void *sh_last; + void *sh_end; + int sh_stack; + int sh_maxorder; + unsigned char **sh_map; + LDAP_LIST_HEAD(sh_freelist, slab_object) *sh_free; + LDAP_LIST_HEAD(sh_so, slab_object) sh_sopool; +}; + +enum { + Align = sizeof(ber_len_t) > 2*sizeof(int) + ? sizeof(ber_len_t) : 2*sizeof(int), + Align_log2 = 1 + (Align>2) + (Align>4) + (Align>8) + (Align>16), + order_start = Align_log2 - 1, + pad = Align - 1 +}; + +static struct slab_object * slap_replenish_sopool(struct slab_heap* sh); +#ifdef SLAPD_UNUSED +static void print_slheap(int level, void *ctx); +#endif + +/* Keep memory context in a thread-local var */ +# define memctx_key ((void *) slap_sl_mem_init) +# define SET_MEMCTX(thrctx, memctx, kfree) \ + ldap_pvt_thread_pool_setkey(thrctx,memctx_key, memctx,kfree, NULL,NULL) +# define GET_MEMCTX(thrctx, memctxp) \ + ((void) (*(memctxp) = NULL), \ + (void) ldap_pvt_thread_pool_getkey(thrctx,memctx_key, memctxp,NULL), \ + *(memctxp)) + +/* Destroy the context, or if key==NULL clean it up for reuse. */ +void +slap_sl_mem_destroy( + void *key, + void *data +) +{ + struct slab_heap *sh = data; + struct slab_object *so; + int i; + + if (!sh) + return; + + if (!sh->sh_stack) { + for (i = 0; i <= sh->sh_maxorder - order_start; i++) { + so = LDAP_LIST_FIRST(&sh->sh_free[i]); + while (so) { + struct slab_object *so_tmp = so; + so = LDAP_LIST_NEXT(so, so_link); + LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_tmp, so_link); + } + ch_free(sh->sh_map[i]); + } + ch_free(sh->sh_free); + ch_free(sh->sh_map); + + so = LDAP_LIST_FIRST(&sh->sh_sopool); + while (so) { + struct slab_object *so_tmp = so; + so = LDAP_LIST_NEXT(so, so_link); + if (!so_tmp->so_blockhead) { + LDAP_LIST_REMOVE(so_tmp, so_link); + } + } + so = LDAP_LIST_FIRST(&sh->sh_sopool); + while (so) { + struct slab_object *so_tmp = so; + so = LDAP_LIST_NEXT(so, so_link); + ch_free(so_tmp); + } + } + + if (key != NULL) { + ber_memfree_x(sh->sh_base, NULL); + ber_memfree_x(sh, NULL); + } +} + +BerMemoryFunctions slap_sl_mfuncs = + { slap_sl_malloc, slap_sl_calloc, slap_sl_realloc, slap_sl_free }; + +void +slap_sl_mem_init() +{ + assert( Align == 1 << Align_log2 ); + + ber_set_option( NULL, LBER_OPT_MEMORY_FNS, &slap_sl_mfuncs ); +} + +/* Create, reset or just return the memory context of the current thread. */ +void * +slap_sl_mem_create( + ber_len_t size, + int stack, + void *thrctx, + int new +) +{ + void *memctx; + struct slab_heap *sh; + ber_len_t size_shift; + struct slab_object *so; + char *base, *newptr; + enum { Base_offset = (unsigned) -sizeof(ber_len_t) % Align }; + + sh = GET_MEMCTX(thrctx, &memctx); + if ( sh && !new ) + return sh; + + /* Round up to doubleword boundary, then make room for initial + * padding, preserving expected available size for pool version */ + size = ((size + Align-1) & -Align) + Base_offset; + + if (!sh) { + sh = ch_malloc(sizeof(struct slab_heap)); + base = ch_malloc(size); + SET_MEMCTX(thrctx, sh, slap_sl_mem_destroy); + VGMEMP_MARK(base, size); + VGMEMP_CREATE(sh, 0, 0); + } else { + slap_sl_mem_destroy(NULL, sh); + base = sh->sh_base; + if (size > (ber_len_t) ((char *) sh->sh_end - base)) { + newptr = ch_realloc(base, size); + if ( newptr == NULL ) return NULL; + VGMEMP_CHANGE(sh, base, newptr, size); + base = newptr; + } + VGMEMP_TRIM(sh, base, 0); + } + sh->sh_base = base; + sh->sh_end = base + size; + + /* Align (base + head of first block) == first returned block */ + base += Base_offset; + size -= Base_offset; + + sh->sh_stack = stack; + if (stack) { + sh->sh_last = base; + + } else { + int i, order = -1, order_end = -1; + + size_shift = size - 1; + do { + order_end++; + } while (size_shift >>= 1); + order = order_end - order_start + 1; + sh->sh_maxorder = order_end; + + sh->sh_free = (struct sh_freelist *) + ch_malloc(order * sizeof(struct sh_freelist)); + for (i = 0; i < order; i++) { + LDAP_LIST_INIT(&sh->sh_free[i]); + } + + LDAP_LIST_INIT(&sh->sh_sopool); + + if (LDAP_LIST_EMPTY(&sh->sh_sopool)) { + slap_replenish_sopool(sh); + } + so = LDAP_LIST_FIRST(&sh->sh_sopool); + LDAP_LIST_REMOVE(so, so_link); + so->so_ptr = base; + + LDAP_LIST_INSERT_HEAD(&sh->sh_free[order-1], so, so_link); + + sh->sh_map = (unsigned char **) + ch_malloc(order * sizeof(unsigned char *)); + for (i = 0; i < order; i++) { + int shiftamt = order_start + 1 + i; + int nummaps = size >> shiftamt; + assert(nummaps); + nummaps >>= 3; + if (!nummaps) nummaps = 1; + sh->sh_map[i] = (unsigned char *) ch_malloc(nummaps); + memset(sh->sh_map[i], 0, nummaps); + } + } + + return sh; +} + +/* + * Assign memory context to thread context. Use NULL to detach + * current memory context from thread. Future users must + * know the context, since ch_free/slap_sl_context() cannot find it. + */ +void +slap_sl_mem_setctx( + void *thrctx, + void *memctx +) +{ + SET_MEMCTX(thrctx, memctx, slap_sl_mem_destroy); +} + +void * +slap_sl_malloc( + ber_len_t size, + void *ctx +) +{ + struct slab_heap *sh = ctx; + ber_len_t *ptr, *newptr; + + /* ber_set_option calls us like this */ + if (No_sl_malloc || !ctx) { + newptr = ber_memalloc_x( size, NULL ); + if ( newptr ) return newptr; + Debug(LDAP_DEBUG_ANY, "slap_sl_malloc of %lu bytes failed\n", + (unsigned long) size ); + assert( 0 ); + exit( EXIT_FAILURE ); + } + + /* Add room for head, ensure room for tail when freed, and + * round up to doubleword boundary. */ + size = (size + sizeof(ber_len_t) + Align-1 + !size) & -Align; + + if (sh->sh_stack) { + if (size < (ber_len_t) ((char *) sh->sh_end - (char *) sh->sh_last)) { + newptr = sh->sh_last; + sh->sh_last = (char *) sh->sh_last + size; + VGMEMP_ALLOC(sh, newptr, size); + *newptr++ = size; + return( (void *)newptr ); + } + + size -= sizeof(ber_len_t); + + } else { + struct slab_object *so_new, *so_left, *so_right; + ber_len_t size_shift; + unsigned long diff; + int i, j, order = -1; + + size_shift = size - 1; + do { + order++; + } while (size_shift >>= 1); + + size -= sizeof(ber_len_t); + + for (i = order; i <= sh->sh_maxorder && + LDAP_LIST_EMPTY(&sh->sh_free[i-order_start]); i++); + + if (i == order) { + so_new = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]); + LDAP_LIST_REMOVE(so_new, so_link); + ptr = so_new->so_ptr; + diff = (unsigned long)((char*)ptr - + (char*)sh->sh_base) >> (order + 1); + sh->sh_map[order-order_start][diff>>3] |= (1 << (diff & 0x7)); + *ptr++ = size; + LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_new, so_link); + return((void*)ptr); + } else if (i <= sh->sh_maxorder) { + for (j = i; j > order; j--) { + so_left = LDAP_LIST_FIRST(&sh->sh_free[j-order_start]); + LDAP_LIST_REMOVE(so_left, so_link); + if (LDAP_LIST_EMPTY(&sh->sh_sopool)) { + slap_replenish_sopool(sh); + } + so_right = LDAP_LIST_FIRST(&sh->sh_sopool); + LDAP_LIST_REMOVE(so_right, so_link); + so_right->so_ptr = (void *)((char *)so_left->so_ptr + (1 << j)); + if (j == order + 1) { + ptr = so_left->so_ptr; + diff = (unsigned long)((char*)ptr - + (char*)sh->sh_base) >> (order+1); + sh->sh_map[order-order_start][diff>>3] |= + (1 << (diff & 0x7)); + *ptr++ = size; + LDAP_LIST_INSERT_HEAD( + &sh->sh_free[j-1-order_start], so_right, so_link); + LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, so_left, so_link); + return((void*)ptr); + } else { + LDAP_LIST_INSERT_HEAD( + &sh->sh_free[j-1-order_start], so_right, so_link); + LDAP_LIST_INSERT_HEAD( + &sh->sh_free[j-1-order_start], so_left, so_link); + } + } + } + /* FIXME: missing return; guessing we failed... */ + } + + Debug(LDAP_DEBUG_TRACE, + "sl_malloc %lu: ch_malloc\n", + (unsigned long) size ); + return ch_malloc(size); +} + +#define LIM_SQRT(t) /* some value < sqrt(max value of unsigned type t) */ \ + ((0UL|(t)-1) >>31>>31 > 1 ? ((t)1 <<32) - 1 : \ + (0UL|(t)-1) >>31 ? 65535U : (0UL|(t)-1) >>15 ? 255U : 15U) + +void * +slap_sl_calloc( ber_len_t n, ber_len_t size, void *ctx ) +{ + void *newptr; + ber_len_t total = n * size; + + /* The sqrt test is a slight optimization: often avoids the division */ + if ((n | size) <= LIM_SQRT(ber_len_t) || n == 0 || total/n == size) { + newptr = slap_sl_malloc( total, ctx ); + memset( newptr, 0, n*size ); + } else { + Debug(LDAP_DEBUG_ANY, "slap_sl_calloc(%lu,%lu) out of range\n", + (unsigned long) n, (unsigned long) size ); + assert(0); + exit(EXIT_FAILURE); + } + return newptr; +} + +void * +slap_sl_realloc(void *ptr, ber_len_t size, void *ctx) +{ + struct slab_heap *sh = ctx; + ber_len_t oldsize, *p = (ber_len_t *) ptr, *nextp; + void *newptr; + + if (ptr == NULL) + return slap_sl_malloc(size, ctx); + + /* Not our memory? */ + if (No_sl_malloc || !sh || ptr < sh->sh_base || ptr >= sh->sh_end) { + /* Like ch_realloc(), except not trying a new context */ + newptr = ber_memrealloc_x(ptr, size, NULL); + if (newptr) { + return newptr; + } + Debug(LDAP_DEBUG_ANY, "slap_sl_realloc of %lu bytes failed\n", + (unsigned long) size ); + assert(0); + exit( EXIT_FAILURE ); + } + + if (size == 0) { + slap_sl_free(ptr, ctx); + return NULL; + } + + oldsize = p[-1]; + + if (sh->sh_stack) { + /* Add room for head, round up to doubleword boundary */ + size = (size + sizeof(ber_len_t) + Align-1) & -Align; + + p--; + + /* Never shrink blocks */ + if (size <= oldsize) { + return ptr; + } + + oldsize &= -2; + nextp = (ber_len_t *) ((char *) p + oldsize); + + /* If reallocing the last block, try to grow it */ + if (nextp == sh->sh_last) { + if (size < (ber_len_t) ((char *) sh->sh_end - (char *) p)) { + sh->sh_last = (char *) p + size; + p[0] = (p[0] & 1) | size; + return ptr; + } + + /* Nowhere to grow, need to alloc and copy */ + } else { + /* Slight optimization of the final realloc variant */ + newptr = slap_sl_malloc(size-sizeof(ber_len_t), ctx); + AC_MEMCPY(newptr, ptr, oldsize-sizeof(ber_len_t)); + /* Not last block, can just mark old region as free */ + nextp[-1] = oldsize; + nextp[0] |= 1; + return newptr; + } + + size -= sizeof(ber_len_t); + oldsize -= sizeof(ber_len_t); + + } else if (oldsize > size) { + oldsize = size; + } + + newptr = slap_sl_malloc(size, ctx); + AC_MEMCPY(newptr, ptr, oldsize); + slap_sl_free(ptr, ctx); + return newptr; +} + +void +slap_sl_free(void *ptr, void *ctx) +{ + struct slab_heap *sh = ctx; + ber_len_t size; + ber_len_t *p = ptr, *nextp, *tmpp; + + if (!ptr) + return; + + if (No_sl_malloc || !sh || ptr < sh->sh_base || ptr >= sh->sh_end) { + ber_memfree_x(ptr, NULL); + return; + } + + size = *(--p); + + if (sh->sh_stack) { + size &= -2; + nextp = (ber_len_t *) ((char *) p + size); + if (sh->sh_last != nextp) { + /* Mark it free: tail = size, head of next block |= 1 */ + nextp[-1] = size; + nextp[0] |= 1; + /* We can't tell Valgrind about it yet, because we + * still need read/write access to this block for + * when we eventually get to reclaim it. + */ + } else { + /* Reclaim freed block(s) off tail */ + while (*p & 1) { + p = (ber_len_t *) ((char *) p - p[-1]); + } + sh->sh_last = p; + VGMEMP_TRIM(sh, sh->sh_base, + (char *) sh->sh_last - (char *) sh->sh_base); + } + + } else { + int size_shift, order_size; + struct slab_object *so; + unsigned long diff; + int i, inserted = 0, order = -1; + + size_shift = size + sizeof(ber_len_t) - 1; + do { + order++; + } while (size_shift >>= 1); + + for (i = order, tmpp = p; i <= sh->sh_maxorder; i++) { + order_size = 1 << (i+1); + diff = (unsigned long)((char*)tmpp - (char*)sh->sh_base) >> (i+1); + sh->sh_map[i-order_start][diff>>3] &= (~(1 << (diff & 0x7))); + if (diff == ((diff>>1)<<1)) { + if (!(sh->sh_map[i-order_start][(diff+1)>>3] & + (1<<((diff+1)&0x7)))) { + so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]); + while (so) { + if ((char*)so->so_ptr == (char*)tmpp) { + LDAP_LIST_REMOVE( so, so_link ); + } else if ((char*)so->so_ptr == + (char*)tmpp + order_size) { + LDAP_LIST_REMOVE(so, so_link); + break; + } + so = LDAP_LIST_NEXT(so, so_link); + } + if (so) { + if (i < sh->sh_maxorder) { + inserted = 1; + so->so_ptr = tmpp; + LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1], + so, so_link); + } + continue; + } else { + if (LDAP_LIST_EMPTY(&sh->sh_sopool)) { + slap_replenish_sopool(sh); + } + so = LDAP_LIST_FIRST(&sh->sh_sopool); + LDAP_LIST_REMOVE(so, so_link); + so->so_ptr = tmpp; + LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start], + so, so_link); + break; + + Debug(LDAP_DEBUG_TRACE, "slap_sl_free: " + "free object not found while bit is clear.\n" ); + assert(so != NULL); + + } + } else { + if (!inserted) { + if (LDAP_LIST_EMPTY(&sh->sh_sopool)) { + slap_replenish_sopool(sh); + } + so = LDAP_LIST_FIRST(&sh->sh_sopool); + LDAP_LIST_REMOVE(so, so_link); + so->so_ptr = tmpp; + LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start], + so, so_link); + } + break; + } + } else { + if (!(sh->sh_map[i-order_start][(diff-1)>>3] & + (1<<((diff-1)&0x7)))) { + so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]); + while (so) { + if ((char*)so->so_ptr == (char*)tmpp) { + LDAP_LIST_REMOVE(so, so_link); + } else if ((char*)tmpp == (char *)so->so_ptr + order_size) { + LDAP_LIST_REMOVE(so, so_link); + tmpp = so->so_ptr; + break; + } + so = LDAP_LIST_NEXT(so, so_link); + } + if (so) { + if (i < sh->sh_maxorder) { + inserted = 1; + LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start+1], so, so_link); + continue; + } + } else { + if (LDAP_LIST_EMPTY(&sh->sh_sopool)) { + slap_replenish_sopool(sh); + } + so = LDAP_LIST_FIRST(&sh->sh_sopool); + LDAP_LIST_REMOVE(so, so_link); + so->so_ptr = tmpp; + LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start], + so, so_link); + break; + + Debug(LDAP_DEBUG_TRACE, "slap_sl_free: " + "free object not found while bit is clear.\n" ); + assert(so != NULL); + + } + } else { + if ( !inserted ) { + if (LDAP_LIST_EMPTY(&sh->sh_sopool)) { + slap_replenish_sopool(sh); + } + so = LDAP_LIST_FIRST(&sh->sh_sopool); + LDAP_LIST_REMOVE(so, so_link); + so->so_ptr = tmpp; + LDAP_LIST_INSERT_HEAD(&sh->sh_free[i-order_start], + so, so_link); + } + break; + } + } + } + } +} + +void +slap_sl_release( void *ptr, void *ctx ) +{ + struct slab_heap *sh = ctx; + if ( sh && ptr >= sh->sh_base && ptr <= sh->sh_end ) + sh->sh_last = ptr; +} + +void * +slap_sl_mark( void *ctx ) +{ + struct slab_heap *sh = ctx; + return sh->sh_last; +} + +/* + * Return the memory context of the current thread if the given block of + * memory belongs to it, otherwise return NULL. + */ +void * +slap_sl_context( void *ptr ) +{ + void *memctx; + struct slab_heap *sh; + + if ( slapMode & SLAP_TOOL_MODE ) return NULL; + + sh = GET_MEMCTX(ldap_pvt_thread_pool_context(), &memctx); + if (sh && ptr >= sh->sh_base && ptr <= sh->sh_end) { + return sh; + } + return NULL; +} + +static struct slab_object * +slap_replenish_sopool( + struct slab_heap* sh +) +{ + struct slab_object *so_block; + int i; + + so_block = (struct slab_object *)ch_malloc( + SLAP_SLAB_SOBLOCK * sizeof(struct slab_object)); + + if ( so_block == NULL ) { + return NULL; + } + + so_block[0].so_blockhead = 1; + LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[0], so_link); + for (i = 1; i < SLAP_SLAB_SOBLOCK; i++) { + so_block[i].so_blockhead = 0; + LDAP_LIST_INSERT_HEAD(&sh->sh_sopool, &so_block[i], so_link ); + } + + return so_block; +} + +#ifdef SLAPD_UNUSED +static void +print_slheap(int level, void *ctx) +{ + struct slab_heap *sh = ctx; + struct slab_object *so; + int i, j, once = 0; + + if (!ctx) { + Debug(level, "NULL memctx\n" ); + return; + } + + Debug(level, "sh->sh_maxorder=%d\n", sh->sh_maxorder ); + + for (i = order_start; i <= sh->sh_maxorder; i++) { + once = 0; + Debug(level, "order=%d\n", i ); + for (j = 0; j < (1<<(sh->sh_maxorder-i))/8; j++) { + Debug(level, "%02x ", sh->sh_map[i-order_start][j] ); + once = 1; + } + if (!once) { + Debug(level, "%02x ", sh->sh_map[i-order_start][0] ); + } + Debug(level, "\n" ); + Debug(level, "free list:\n" ); + so = LDAP_LIST_FIRST(&sh->sh_free[i-order_start]); + while (so) { + Debug(level, "%p\n", so->so_ptr ); + so = LDAP_LIST_NEXT(so, so_link); + } + } +} +#endif -- cgit v1.2.3