From owner-freebsd-current@freebsd.org Fri Jan 12 19:37:07 2018 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id D44D1E77F91 for ; Fri, 12 Jan 2018 19:37:07 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 5205C7BEE2 for ; Fri, 12 Jan 2018 19:37:07 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kib@localhost [127.0.0.1]) by kib.kiev.ua (8.15.2/8.15.2) with ESMTPS id w0CJaxop023848 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Fri, 12 Jan 2018 21:37:02 +0200 (EET) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua w0CJaxop023848 Received: (from kostik@localhost) by tom.home (8.15.2/8.15.2/Submit) id w0CJaxpA023847; Fri, 12 Jan 2018 21:36:59 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Fri, 12 Jan 2018 21:36:59 +0200 From: Konstantin Belousov To: Eric van Gyzen Cc: FreeBSD Current Subject: Re: td_swvoltick Message-ID: <20180112193659.GL1684@kib.kiev.ua> References: <603d2786-86be-583c-9ff6-d8d73eddf77e@vangyzen.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <603d2786-86be-583c-9ff6-d8d73eddf77e@vangyzen.net> User-Agent: Mutt/1.9.2 (2017-12-15) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.1 X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on tom.home X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Jan 2018 19:37:07 -0000 On Fri, Jan 12, 2018 at 01:31:41PM -0600, Eric van Gyzen wrote: > should_yield() compares thread::td_swvoltick to 'ticks' to determine > whether a thread is hogging and should yield. Since td_swvoltick > records 'ticks' /before/ the actual context switch, the calculation in > should_yield() includes any time that the thread was switched out. It > seems that should_yield() wants to know how long the thread has actually > been running. Therefore, td_swvoltick should record 'ticks' /after/ > sched_switch() returns. > > Does this make sense, or am I missing something? Yes, it does make sense to me. > > If this makes sense, I would probably keep the current assignment in > mi_switch() and simply add a second assignment after the call to > sched_switch(). That way, db_show_thread will still show useful data > for sleeping threads. I would do the same for td_swinvolticks. > > I'll be happy to make the change myself. I just want a sanity check > before I bother. > > Thanks in advance, > > Eric > _______________________________________________ > freebsd-current@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org"