Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262709AbVAVUfx (ORCPT ); Sat, 22 Jan 2005 15:35:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262743AbVAVUfx (ORCPT ); Sat, 22 Jan 2005 15:35:53 -0500 Received: from ns.suse.de ([195.135.220.2]:41936 "EHLO Cantor.suse.de") by vger.kernel.org with ESMTP id S262709AbVAVUe3 (ORCPT ); Sat, 22 Jan 2005 15:34:29 -0500 Message-Id: <20050122203618.962749000@blunzn.suse.de> References: <20050122203326.402087000@blunzn.suse.de> Date: Sat, 22 Jan 2005 21:34:01 +0100 From: Andreas Gruenbacher To: linux-kernel@vger.kernel.org, Neil Brown , Trond Myklebust Cc: Olaf Kirch , "Andries E. Brouwer" , Buck Huppmann , Andrew Morton Subject: [patch 1/13] Qsort Content-Disposition: inline; filename=patches.suse/qsort Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 18829 Lines: 553 Add a quicksort from glibc as a kernel library function, and switch xfs over to using it. The implementations are equivalent. The nfsacl protocol also requires a sort function, so it makes more sense in the common code. Signed-off-by: Andreas Gruenbacher Acked-by: Olaf Kirch Index: linux-2.6.11-rc2/include/linux/kernel.h =================================================================== --- linux-2.6.11-rc2.orig/include/linux/kernel.h +++ linux-2.6.11-rc2/include/linux/kernel.h @@ -93,6 +93,8 @@ extern int sscanf(const char *, const ch __attribute__ ((format (scanf,2,3))); extern int vsscanf(const char *, const char *, va_list); +extern void qsort(void *, size_t, size_t, int (*)(const void *,const void *)); + extern int get_option(char **str, int *pint); extern char *get_options(const char *str, int nints, int *ints); extern unsigned long long memparse(char *ptr, char **retptr); Index: linux-2.6.11-rc2/lib/Kconfig =================================================================== --- linux-2.6.11-rc2.orig/lib/Kconfig +++ linux-2.6.11-rc2/lib/Kconfig @@ -30,6 +30,9 @@ config LIBCRC32C require M here. See Castagnoli93. Module will be libcrc32c. +config QSORT + bool "Quick Sort" + # # compression support is select'ed if needed # Index: linux-2.6.11-rc2/lib/Makefile =================================================================== --- linux-2.6.11-rc2.orig/lib/Makefile +++ linux-2.6.11-rc2/lib/Makefile @@ -25,6 +25,7 @@ obj-$(CONFIG_CRC_CCITT) += crc-ccitt.o obj-$(CONFIG_CRC32) += crc32.o obj-$(CONFIG_LIBCRC32C) += libcrc32c.o obj-$(CONFIG_GENERIC_IOMAP) += iomap.o +obj-$(CONFIG_QSORT) += qsort.o obj-$(CONFIG_ZLIB_INFLATE) += zlib_inflate/ obj-$(CONFIG_ZLIB_DEFLATE) += zlib_deflate/ Index: linux-2.6.11-rc2/lib/qsort.c =================================================================== --- /dev/null +++ linux-2.6.11-rc2/lib/qsort.c @@ -0,0 +1,249 @@ +/* Copyright (C) 1991, 1992, 1996, 1997, 1999 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Written by Douglas C. Schmidt (schmidt@ics.uci.edu). + + The GNU C 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. + + The GNU C 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 the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +/* If you consider tuning this algorithm, you should consult first: + Engineering a sort function; Jon Bentley and M. Douglas McIlroy; + Software - Practice and Experience; Vol. 23 (11), 1249-1265, 1993. */ + +# include +# include +# include + +MODULE_LICENSE("GPL"); + +/* Byte-wise swap two items of size SIZE. */ +#define SWAP(a, b, size) \ + do \ + { \ + register size_t __size = (size); \ + register char *__a = (a), *__b = (b); \ + do \ + { \ + char __tmp = *__a; \ + *__a++ = *__b; \ + *__b++ = __tmp; \ + } while (--__size > 0); \ + } while (0) + +/* Discontinue quicksort algorithm when partition gets below this size. + This particular magic number was chosen to work best on a Sun 4/260. */ +#define MAX_THRESH 4 + +/* Stack node declarations used to store unfulfilled partition obligations. */ +typedef struct + { + char *lo; + char *hi; + } stack_node; + +/* The next 5 #defines implement a very fast in-line stack abstraction. */ +/* The stack needs log (total_elements) entries (we could even subtract + log(MAX_THRESH)). Since total_elements has type size_t, we get as + upper bound for log (total_elements): + bits per byte (CHAR_BIT) * sizeof(size_t). */ +#define CHAR_BIT 8 +#define STACK_SIZE (CHAR_BIT * sizeof(size_t)) +#define PUSH(low, high) ((void) ((top->lo = (low)), (top->hi = (high)), ++top)) +#define POP(low, high) ((void) (--top, (low = top->lo), (high = top->hi))) +#define STACK_NOT_EMPTY (stack < top) + + +/* Order size using quicksort. This implementation incorporates + four optimizations discussed in Sedgewick: + + 1. Non-recursive, using an explicit stack of pointer that store the + next array partition to sort. To save time, this maximum amount + of space required to store an array of SIZE_MAX is allocated on the + stack. Assuming a 32-bit (64 bit) integer for size_t, this needs + only 32 * sizeof(stack_node) == 256 bytes (for 64 bit: 1024 bytes). + Pretty cheap, actually. + + 2. Chose the pivot element using a median-of-three decision tree. + This reduces the probability of selecting a bad pivot value and + eliminates certain extraneous comparisons. + + 3. Only quicksorts TOTAL_ELEMS / MAX_THRESH partitions, leaving + insertion sort to order the MAX_THRESH items within each partition. + This is a big win, since insertion sort is faster for small, mostly + sorted array segments. + + 4. The larger of the two sub-partitions is always pushed onto the + stack first, with the algorithm then concentrating on the + smaller partition. This *guarantees* no more than log (total_elems) + stack size is needed (actually O(1) in this case)! */ + +void +qsort(void *const pbase, size_t total_elems, size_t size, + int(*cmp)(const void *,const void *)) +{ + register char *base_ptr = (char *) pbase; + + const size_t max_thresh = MAX_THRESH * size; + + if (total_elems == 0) + /* Avoid lossage with unsigned arithmetic below. */ + return; + + if (total_elems > MAX_THRESH) + { + char *lo = base_ptr; + char *hi = &lo[size * (total_elems - 1)]; + stack_node stack[STACK_SIZE]; + stack_node *top = stack + 1; + + while (STACK_NOT_EMPTY) + { + char *left_ptr; + char *right_ptr; + + /* Select median value from among LO, MID, and HI. Rearrange + LO and HI so the three values are sorted. This lowers the + probability of picking a pathological pivot value and + skips a comparison for both the LEFT_PTR and RIGHT_PTR in + the while loops. */ + + char *mid = lo + size * ((hi - lo) / size >> 1); + + if ((*cmp) ((void *) mid, (void *) lo) < 0) + SWAP (mid, lo, size); + if ((*cmp) ((void *) hi, (void *) mid) < 0) + SWAP (mid, hi, size); + else + goto jump_over; + if ((*cmp) ((void *) mid, (void *) lo) < 0) + SWAP (mid, lo, size); + jump_over:; + + left_ptr = lo + size; + right_ptr = hi - size; + + /* Here's the famous ``collapse the walls'' section of quicksort. + Gotta like those tight inner loops! They are the main reason + that this algorithm runs much faster than others. */ + do + { + while ((*cmp) ((void *) left_ptr, (void *) mid) < 0) + left_ptr += size; + + while ((*cmp) ((void *) mid, (void *) right_ptr) < 0) + right_ptr -= size; + + if (left_ptr < right_ptr) + { + SWAP (left_ptr, right_ptr, size); + if (mid == left_ptr) + mid = right_ptr; + else if (mid == right_ptr) + mid = left_ptr; + left_ptr += size; + right_ptr -= size; + } + else if (left_ptr == right_ptr) + { + left_ptr += size; + right_ptr -= size; + break; + } + } + while (left_ptr <= right_ptr); + + /* Set up pointers for next iteration. First determine whether + left and right partitions are below the threshold size. If so, + ignore one or both. Otherwise, push the larger partition's + bounds on the stack and continue sorting the smaller one. */ + + if ((size_t) (right_ptr - lo) <= max_thresh) + { + if ((size_t) (hi - left_ptr) <= max_thresh) + /* Ignore both small partitions. */ + POP (lo, hi); + else + /* Ignore small left partition. */ + lo = left_ptr; + } + else if ((size_t) (hi - left_ptr) <= max_thresh) + /* Ignore small right partition. */ + hi = right_ptr; + else if ((right_ptr - lo) > (hi - left_ptr)) + { + /* Push larger left partition indices. */ + PUSH (lo, right_ptr); + lo = left_ptr; + } + else + { + /* Push larger right partition indices. */ + PUSH (left_ptr, hi); + hi = right_ptr; + } + } + } + + /* Once the BASE_PTR array is partially sorted by quicksort the rest + is completely sorted using insertion sort, since this is efficient + for partitions below MAX_THRESH size. BASE_PTR points to the beginning + of the array to sort, and END_PTR points at the very last element in + the array (*not* one beyond it!). */ + + { + char *end_ptr = &base_ptr[size * (total_elems - 1)]; + char *tmp_ptr = base_ptr; + char *thresh = min(end_ptr, base_ptr + max_thresh); + register char *run_ptr; + + /* Find smallest element in first threshold and place it at the + array's beginning. This is the smallest array element, + and the operation speeds up insertion sort's inner loop. */ + + for (run_ptr = tmp_ptr + size; run_ptr <= thresh; run_ptr += size) + if ((*cmp) ((void *) run_ptr, (void *) tmp_ptr) < 0) + tmp_ptr = run_ptr; + + if (tmp_ptr != base_ptr) + SWAP (tmp_ptr, base_ptr, size); + + /* Insertion sort, running from left-hand-side up to right-hand-side. */ + + run_ptr = base_ptr + size; + while ((run_ptr += size) <= end_ptr) + { + tmp_ptr = run_ptr - size; + while ((*cmp) ((void *) run_ptr, (void *) tmp_ptr) < 0) + tmp_ptr -= size; + + tmp_ptr += size; + if (tmp_ptr != run_ptr) + { + char *trav; + + trav = run_ptr + size; + while (--trav >= run_ptr) + { + char c = *trav; + char *hi, *lo; + + for (hi = lo = trav; (lo -= size) >= tmp_ptr; hi = lo) + *hi = *lo; + *hi = c; + } + } + } + } +} +EXPORT_SYMBOL(qsort); Index: linux-2.6.11-rc2/fs/xfs/support/qsort.c =================================================================== --- linux-2.6.11-rc2.orig/fs/xfs/support/qsort.c +++ /dev/null @@ -1,155 +0,0 @@ -/* - * Copyright (c) 1992, 1993 - * The Regents of the University of California. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#include -#include - -/* - * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function". - */ -#define swapcode(TYPE, parmi, parmj, n) { \ - long i = (n) / sizeof (TYPE); \ - register TYPE *pi = (TYPE *) (parmi); \ - register TYPE *pj = (TYPE *) (parmj); \ - do { \ - register TYPE t = *pi; \ - *pi++ = *pj; \ - *pj++ = t; \ - } while (--i > 0); \ -} - -#define SWAPINIT(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \ - es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1; - -static __inline void -swapfunc(char *a, char *b, int n, int swaptype) -{ - if (swaptype <= 1) - swapcode(long, a, b, n) - else - swapcode(char, a, b, n) -} - -#define swap(a, b) \ - if (swaptype == 0) { \ - long t = *(long *)(a); \ - *(long *)(a) = *(long *)(b); \ - *(long *)(b) = t; \ - } else \ - swapfunc(a, b, es, swaptype) - -#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype) - -static __inline char * -med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *)) -{ - return cmp(a, b) < 0 ? - (cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a )) - :(cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c )); -} - -void -qsort(void *aa, size_t n, size_t es, int (*cmp)(const void *, const void *)) -{ - char *pa, *pb, *pc, *pd, *pl, *pm, *pn; - int d, r, swaptype, swap_cnt; - register char *a = aa; - -loop: SWAPINIT(a, es); - swap_cnt = 0; - if (n < 7) { - for (pm = (char *)a + es; pm < (char *) a + n * es; pm += es) - for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0; - pl -= es) - swap(pl, pl - es); - return; - } - pm = (char *)a + (n / 2) * es; - if (n > 7) { - pl = (char *)a; - pn = (char *)a + (n - 1) * es; - if (n > 40) { - d = (n / 8) * es; - pl = med3(pl, pl + d, pl + 2 * d, cmp); - pm = med3(pm - d, pm, pm + d, cmp); - pn = med3(pn - 2 * d, pn - d, pn, cmp); - } - pm = med3(pl, pm, pn, cmp); - } - swap(a, pm); - pa = pb = (char *)a + es; - - pc = pd = (char *)a + (n - 1) * es; - for (;;) { - while (pb <= pc && (r = cmp(pb, a)) <= 0) { - if (r == 0) { - swap_cnt = 1; - swap(pa, pb); - pa += es; - } - pb += es; - } - while (pb <= pc && (r = cmp(pc, a)) >= 0) { - if (r == 0) { - swap_cnt = 1; - swap(pc, pd); - pd -= es; - } - pc -= es; - } - if (pb > pc) - break; - swap(pb, pc); - swap_cnt = 1; - pb += es; - pc -= es; - } - if (swap_cnt == 0) { /* Switch to insertion sort */ - for (pm = (char *) a + es; pm < (char *) a + n * es; pm += es) - for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0; - pl -= es) - swap(pl, pl - es); - return; - } - - pn = (char *)a + n * es; - r = min(pa - (char *)a, pb - pa); - vecswap(a, pb - r, r); - r = min((long)(pd - pc), (long)(pn - pd - es)); - vecswap(pb, pn - r, r); - if ((r = pb - pa) > es) - qsort(a, r / es, es, cmp); - if ((r = pd - pc) > es) { - /* Iterate rather than recurse to save stack space */ - a = pn - r; - n = r / es; - goto loop; - } -/* qsort(pn - r, r / es, es, cmp);*/ -} Index: linux-2.6.11-rc2/fs/xfs/Makefile =================================================================== --- linux-2.6.11-rc2.orig/fs/xfs/Makefile +++ linux-2.6.11-rc2/fs/xfs/Makefile @@ -142,7 +142,6 @@ xfs-y += $(addprefix linux-2.6/, \ xfs-y += $(addprefix support/, \ debug.o \ move.o \ - qsort.o \ uuid.o) xfs-$(CONFIG_XFS_TRACE) += support/ktrace.o Index: linux-2.6.11-rc2/fs/xfs/support/qsort.h =================================================================== --- linux-2.6.11-rc2.orig/fs/xfs/support/qsort.h +++ /dev/null @@ -1,41 +0,0 @@ -/* - * Copyright (c) 2000-2002 Silicon Graphics, Inc. All Rights Reserved. - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of version 2 of the GNU General Public License as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it would be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. - * - * Further, this software is distributed without any warranty that it is - * free of the rightful claim of any third person regarding infringement - * or the like. Any license provided herein, whether implied or - * otherwise, applies only to this software file. Patent licenses, if - * any, provided herein do not apply to combinations of this program with - * other software, or any other product whatsoever. - * - * You should have received a copy of the GNU General Public License along - * with this program; if not, write the Free Software Foundation, Inc., 59 - * Temple Place - Suite 330, Boston MA 02111-1307, USA. - * - * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy, - * Mountain View, CA 94043, or: - * - * http://www.sgi.com - * - * For further information regarding this notice, see: - * - * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/ - */ - -#ifndef QSORT_H -#define QSORT_H - -extern void qsort (void *const pbase, - size_t total_elems, - size_t size, - int (*cmp)(const void *, const void *)); - -#endif Index: linux-2.6.11-rc2/fs/xfs/linux-2.6/xfs_linux.h =================================================================== --- linux-2.6.11-rc2.orig/fs/xfs/linux-2.6/xfs_linux.h +++ linux-2.6.11-rc2/fs/xfs/linux-2.6/xfs_linux.h @@ -64,7 +64,6 @@ #include #include -#include #include #include #include Index: linux-2.6.11-rc2/fs/Kconfig =================================================================== --- linux-2.6.11-rc2.orig/fs/Kconfig +++ linux-2.6.11-rc2/fs/Kconfig @@ -306,6 +306,7 @@ config FS_POSIX_ACL config XFS_FS tristate "XFS filesystem support" + select QSORT help XFS is a high performance journaling filesystem which originated on the SGI IRIX platform. It is completely multi-threaded, can -- Andreas Gruenbacher SUSE Labs, SUSE LINUX PRODUCTS GMBH - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/