From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264061AbUFKPWz (ORCPT ); Fri, 11 Jun 2004 11:22:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264085AbUFKPWy (ORCPT ); Fri, 11 Jun 2004 11:22:54 -0400 Received: from mx1.redhat.com ([66.187.233.31]:33947 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S264058AbUFKPVW (ORCPT ); Fri, 11 Jun 2004 11:21:22 -0400 From: David Howells To: Andi Kleen Cc: linux-kernel@vger.kernel.org Subject: R/W semaphore tester module User-Agent: EMH/1.14.1 SEMI/1.14.5 (Awara-Onsen) FLIM/1.14.5 (Demachiyanagi) APEL/10.6 Emacs/21.3 (i386-redhat-linux-gnu) MULE/5.0 (SAKAKI) MIME-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: multipart/mixed; boundary="Multipart_Fri_Jun_11_16:21:17_2004-1" Date: Fri, 11 Jun 2004 16:21:17 +0100 Message-ID: <7717.1086967277@redhat.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --Multipart_Fri_Jun_11_16:21:17_2004-1 Content-Type: text/plain; charset=US-ASCII Hi Andi, I rendered my rwsem testsuite down to a single module that takes a bunch of parameters to tell it how many threads to run. Run the module with something like: insmod /tmp/rwsem-any.ko numrd=10 numwr=4 numdg=4 elapse=30 do_sched=1 And it'll start 10 reader threads, 4 writer threads, and 4 write-downgrade threads. It'll run for 30 seconds, and each thread will invoke schedule() after every cycle. The module will exit on error ENOANO if successful so that it doesn't need to be removed later: [root@host135 root]# insmod /tmp/rwsem-any.ko Error inserting `/tmp/rwsem-any.ko': -1 No anode And it'll print a summary to the kernel console: rwsem_any starting tests... Write0: done Read0: done Down0: done rwsem counter = 0 reads taken: 90636 writes taken: 181496 downgrades taken: 90648 David --Multipart_Fri_Jun_11_16:21:17_2004-1 Content-Type: text/plain; charset=US-ASCII /* rwsem-any.c: run some threads to do R/W semaphore tests * * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * 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 of the License, or (at your option) any later version. */ #include #include #include #include #include #include #include #include #include #include #include #include #include "check.h" #define SCHED static int numrd = 1, numwr = 1, numdg = 1, elapse = 5; MODULE_AUTHOR("David Howells"); MODULE_DESCRIPTION("R/W semaphore test demo"); MODULE_LICENSE("GPL"); module_param(numrd, int, 0); MODULE_PARM_DESC(numrd, "Number of reader threads"); module_param(numwr, int, 0); MODULE_PARM_DESC(numwr, "Number of writer threads"); module_param(numdg, int, 0); MODULE_PARM_DESC(numdg, "Number of downgrader threads"); module_param(elapse, int, 0); MODULE_PARM_DESC(elapse, "Number of seconds to run for"); #ifdef SCHED static int do_sched = 0; module_param(do_sched, int, 0); MODULE_PARM_DESC(numdg, "True if each thread should schedule regularly"); #endif /* the semaphore under test */ static struct rw_semaphore rwsem_sem; #ifdef DEBUG_RWSEM extern struct rw_semaphore *rwsem_to_monitor; #endif static atomic_t readers = ATOMIC_INIT(0); static atomic_t writers = ATOMIC_INIT(0); static atomic_t do_stuff = ATOMIC_INIT(0); static atomic_t reads_taken = ATOMIC_INIT(0); static atomic_t writes_taken = ATOMIC_INIT(0); static atomic_t downgrades_taken = ATOMIC_INIT(0); static struct completion rd_comp[20], wr_comp[20], dg_comp[20]; static struct timer_list timer; static inline void dr(void) { down_read(&rwsem_sem); atomic_inc(&readers); atomic_inc(&reads_taken); CHECKA(writers, 0); } static inline void ur(void) { CHECKA(writers, 0); atomic_dec(&readers); up_read(&rwsem_sem); } static inline void dw(void) { down_write(&rwsem_sem); atomic_inc(&writers); atomic_inc(&writes_taken); CHECKA(writers, 1); CHECKA(readers, 0); } static inline void uw(void) { CHECKA(writers, 1); CHECKA(readers, 0); atomic_dec(&writers); up_write(&rwsem_sem); } static inline void dgw(void) { CHECKA(writers, 1); CHECKA(readers, 0); atomic_dec(&writers); atomic_inc(&readers); downgrade_write(&rwsem_sem); atomic_inc(&downgrades_taken); } static inline void sched(void) { #ifdef SCHED if (do_sched) schedule(); #endif } int reader(void *arg) { unsigned int N = (unsigned long) arg; daemonize("Read%u", N); while (atomic_read(&do_stuff)) { dr(); ur(); sched(); } printk("%s: done\n", current->comm); complete_and_exit(&rd_comp[N], 0); } int writer(void *arg) { unsigned int N = (unsigned long) arg; daemonize("Write%u", N); while (atomic_read(&do_stuff)) { dw(); uw(); sched(); } printk("%s: done\n", current->comm); complete_and_exit(&wr_comp[N], 0); } int downgrader(void *arg) { unsigned int N = (unsigned long) arg; daemonize("Down%u", N); while (atomic_read(&do_stuff)) { dw(); dgw(); ur(); sched(); } printk("%s: done\n", current->comm); complete_and_exit(&dg_comp[N], 0); } static void stop_test(unsigned long dummy) { atomic_set(&do_stuff, 0); } /*****************************************************************************/ /* * */ static int __init rwsem_init_module(void) { unsigned long loop; printk("\nrwsem_any starting tests...\n"); init_rwsem(&rwsem_sem); atomic_set(&do_stuff, 1); #ifdef DEBUG_RWSEM rwsem_to_monitor = &rwsem_sem; #endif /* kick off all the children */ for (loop = 0; loop < 20; loop++) { if (loop < numrd) { init_completion(&rd_comp[loop]); kernel_thread(reader, (void *) loop, 0); } if (loop < numwr) { init_completion(&wr_comp[loop]); kernel_thread(writer, (void *) loop, 0); } if (loop < numdg) { init_completion(&dg_comp[loop]); kernel_thread(downgrader, (void *) loop, 0); } } /* set a stop timer */ init_timer(&timer); timer.function = stop_test; timer.expires = jiffies + elapse * HZ; add_timer(&timer); /* now wait until it's all done */ for (loop = 0; loop < numrd; loop++) wait_for_completion(&rd_comp[loop]); for (loop = 0; loop < numwr; loop++) wait_for_completion(&wr_comp[loop]); for (loop = 0; loop < numdg; loop++) wait_for_completion(&dg_comp[loop]); atomic_set(&do_stuff, 0); del_timer(&timer); /* print the results */ #ifdef CONFIG_RWSEM_XCHGADD_ALGORITHM printk("rwsem counter = %ld\n", rwsem_sem.count); #else printk("rwsem counter = %d\n", rwsem_sem.activity); #endif printk("reads taken: %d\n", atomic_read(&reads_taken)); printk("writes taken: %d\n", atomic_read(&writes_taken)); printk("downgrades taken: %d\n", atomic_read(&downgrades_taken)); #ifdef DEBUG_RWSEM rwsem_to_monitor = NULL; #endif /* tell insmod to discard the module */ return -ENOANO; } /* end rwsem_init_module() */ module_init(rwsem_init_module); --Multipart_Fri_Jun_11_16:21:17_2004-1--