From owner-freebsd-hackers@FreeBSD.ORG Mon Mar 14 15:59:06 2011 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4925E1065673 for ; Mon, 14 Mar 2011 15:59:06 +0000 (UTC) (envelope-from ravi.murty@gmail.com) Received: from mail-bw0-f54.google.com (mail-bw0-f54.google.com [209.85.214.54]) by mx1.freebsd.org (Postfix) with ESMTP id BE4E98FC0A for ; Mon, 14 Mar 2011 15:59:05 +0000 (UTC) Received: by bwz12 with SMTP id 12so5078710bwz.13 for ; Mon, 14 Mar 2011 08:59:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=JFPvkwObzSFBXKn1wEqMkOpryQ1zD/C83amZZc5vxvo=; b=YgBgfnjmVH9OYpJQeR5FTTjJGtr3z+1+sJkOK7ewloJ7JWNrbDof3W7Xz4XF5yYDJI K3TMxXg5H0HSENDvjtHqTezuCEnwszI21/WtUPmpDp5Lt4lU3QywfPtOz6XO4/R9rmZu BlFZbozPZj9VO3C1UprAZVJueDTbckOVgMfJc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=aq9zIH2UwSbr+im6XfeUTlygfHEc/7E1PVmIn6B+LyN+muTCjv9e3LONFvDuVmoUvQ wtoVTF9HLHe4YhFvykZmzayGUdm4fde/QQ+OZf7tILHukDW+iqcQTkTW1d2yP2h6Ur7T hV5yQLkeEMphgejInewMpqCHJ9fo2cJJk02t8= MIME-Version: 1.0 Received: by 10.204.29.21 with SMTP id o21mr5468501bkc.97.1300118344574; Mon, 14 Mar 2011 08:59:04 -0700 (PDT) Received: by 10.204.117.193 with HTTP; Mon, 14 Mar 2011 08:59:04 -0700 (PDT) In-Reply-To: <20110314090318.GG78089@deviant.kiev.zoral.com.ua> References: <201103141230.49277.erich@alogreentechnologies.com> <20110314090318.GG78089@deviant.kiev.zoral.com.ua> Date: Mon, 14 Mar 2011 08:59:04 -0700 Message-ID: From: Ravi Murty To: Kostik Belousov Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: "freebsd-hackers@freebsd.org" , Erich Dollansky Subject: Re: SIGSTOP and SIGKILL X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 14 Mar 2011 15:59:06 -0000 I haven't tried sending a SIGCONT after this state. I see that one thread of the process has SIGSTOP still on its signal list, the SIGKILL is cleared because that's what the process was trying to do when it got caught and stopped instead. Before this happens, SIGCONT seems to be able to bring the threads back out of stopped state without any problems. Ravi On Mon, Mar 14, 2011 at 2:03 AM, Kostik Belousov wrote: > On Sun, Mar 13, 2011 at 11:30:00PM -0700, Ravi Murty wrote: > > I haven't, are there specific improvements in this area of the kernel? > First, the 8.2, compared to 8.0, changed the mechanism of delivering > the process-global signal to a thread. Now, the thread to deliver is > selected at the moment of delivery, instead of the moment of post. > This was done to close a race where either thread changed signal mask > after post, or exited after post, causing signal be undefinitely > delayed or ignored, respectively. > > Second, 8.2 less often stops the threads in the sleep state, more often > trying to move the thread to safer user<->kernel boundary, to take a stop. > Sleeping thread might indicate the unsafe sleep (from the POV of stopping) > by using PBDRY flag to msleep. > > Both the changes are not directly address the behaviour you described, > but they are explicitely in the area of your interest. > > BTW, it is not clear to me, does the process in the state as you > described, able to unwind from the stop state using SIGCONT ? I.e., > is it 'weird but recoverable' state, or is it 'weird and unrecoverable' > state ? > > > > On Mar 13, 2011, at 10:30 PM, Erich Dollansky < > erich@alogreentechnologies.com> wrote: > > > > > Hi, > > > > > > On Monday 14 March 2011 11:41:21 Ravi Murty wrote: > > > > > >> > > >> Any good solutions to this problem? > > > > > > did you try your program on 8.2? > > > > > > Erich > > _______________________________________________ > > freebsd-hackers@freebsd.org mailing list > > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > > To unsubscribe, send any mail to " > freebsd-hackers-unsubscribe@freebsd.org" >