Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 15 Jul 2002 06:01:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 15 Jul 2002 06:01:32 -0400 Received: from holomorphy.com ([66.224.33.161]:60583 "EHLO holomorphy") by vger.kernel.org with ESMTP id ; Mon, 15 Jul 2002 06:01:31 -0400 Date: Mon, 15 Jul 2002 03:03:10 -0700 From: William Lee Irwin III To: Russell King Cc: linux-kernel@vger.kernel.org Subject: Re: Serial: updated serial drivers Message-ID: <20020715100310.GF23693@holomorphy.com> Mail-Followup-To: William Lee Irwin III , Russell King , linux-kernel@vger.kernel.org References: <20020707010009.C5242@flint.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Description: brief message Content-Disposition: inline In-Reply-To: <20020707010009.C5242@flint.arm.linux.org.uk> User-Agent: Mutt/1.3.25i Organization: The Domain of Holomorphy Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2070 Lines: 43 On Sun, Jul 07, 2002 at 01:00:09AM +0100, Russell King wrote: > I've been maintaining a serial driver "off the side" of the ARM port > which cleans up the serial driver mess that we currently have, with > many duplications of serial.c, each with subtle bugs. global_cli() overhead on my testbox is a significant problem. Profile info from tbench 1024 with ttyS0 as stdout, taken on a 16 cpu i386 box with 16GB of RAM and irqbalance disabled, (needed to boot): 90372662 total 713.6412 44801051 default_idle 861558.6731 36220921 mod_timer 113190.3781 2510075 timer_bh 2764.3998 2344795 __global_cli 8620.5699 1446315 __wake_up 7693.1649 1370742 do_gettimeofday 10078.9853 924996 schedule 831.8309 512368 do_softirq 2328.9455 103136 tasklet_hi_action 526.2041 40640 system_call 923.6364 19238 do_page_fault 14.2927 12835 add_wait_queue 103.5081 10667 remove_wait_queue 83.3359 7990 bh_action 38.4135 5303 pte_alloc_one 27.6198 4665 schedule_timeout 29.1562 4584 pgd_alloc 24.3830 3870 syscall_call 351.8182 3633 try_to_wake_up 6.3073 3100 exit_notify 3.5068 2566 del_timer 14.9186 The disabling of irqbalance should make these profiling results valid. Cheers, Bill - 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/