From nobody Tue Sep 19 15:41:33 2023 X-Original-To: hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4Rqm9f4Qcxz4v3x0 for ; Tue, 19 Sep 2023 15:41:42 +0000 (UTC) (envelope-from phk@critter.freebsd.dk) Received: from phk.freebsd.dk (phk.freebsd.dk [130.225.244.222]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4Rqm9d6JyXz4lZQ for ; Tue, 19 Sep 2023 15:41:41 +0000 (UTC) (envelope-from phk@critter.freebsd.dk) Authentication-Results: mx1.freebsd.org; none Received: from critter.freebsd.dk (unknown [192.168.55.3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by phk.freebsd.dk (Postfix) with ESMTPS id AA68E89293; Tue, 19 Sep 2023 15:41:33 +0000 (UTC) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.17.1/8.16.1) with ESMTPS id 38JFfXE9073413 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Tue, 19 Sep 2023 15:41:33 GMT (envelope-from phk@critter.freebsd.dk) Received: (from phk@localhost) by critter.freebsd.dk (8.17.1/8.16.1/Submit) id 38JFfXnb073412; Tue, 19 Sep 2023 15:41:33 GMT (envelope-from phk) Message-Id: <202309191541.38JFfXnb073412@critter.freebsd.dk> To: Sebastian Huber cc: hackers@freebsd.org Subject: Re: Remove timecounter tc_counter_mask member? In-reply-to: From: "Poul-Henning Kamp" References: <202309162044.38GKi7RZ022115@critter.freebsd.dk> List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <73410.1695138093.1@critter.freebsd.dk> Date: Tue, 19 Sep 2023 15:41:33 +0000 X-Spamd-Bar: ---- X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:1835, ipnet:130.225.0.0/16, country:EU] X-Rspamd-Queue-Id: 4Rqm9d6JyXz4lZQ -------- Sebastian Huber writes: > On 16.09.23 22:44, Poul-Henning Kamp wrote: > > Sebastian Huber writes: > > > >> the timecounter structure contains a tc_counter_mask which enables > >> support for time counters implementing less than 32-bits: > >> Is the sys/x86/isa/clock.c still used? Are there chips on the market > >> with 24-bit ACPI timers? > > ... and are there any FreeBSD platforms using narrow timecounters > > outside the src-tree ? > > > > My personal gut feeling, is that we can get away with it, once i386 > > is out of the picture. > > If it is in principle acceptable to remove the tc_counter_mask at some > point in time, would it make sense to issue a warning if a timecounter > is installed with a mask not equal to 0xffffffff? It would be a good a way to warn people... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.