From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: MPS: profiler Date: Fri, 21 Jun 2024 17:10:08 +0300 Message-ID: <868qyyl73z.fsf@gnu.org> References: <87v823xvq1.fsf@localhost> <86cyobmmhc.fsf@gnu.org> <87r0crxung.fsf@localhost> <87le2zxsqx.fsf@localhost> <8634p6n7jd.fsf@gnu.org> <87tthm3gq2.fsf@gmail.com> <87sex6ags5.fsf@localhost> <87msne3flr.fsf@gmail.com> <87frt63dvt.fsf@gmail.com> <86o77ulgk8.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="29580"; mail-complaints-to="usenet@ciao.gmane.io" Cc: eller.helmut@gmail.com, yantar92@posteo.net, emacs-devel@gnu.org To: Gerd =?iso-8859-1?Q?M=F6llmann?= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Jun 21 16:11:06 2024 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1sKeyo-0007Qx-Dn for ged-emacs-devel@m.gmane-mx.org; Fri, 21 Jun 2024 16:11:06 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sKey6-0001DO-On; Fri, 21 Jun 2024 10:10:22 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sKey4-0001Aa-Sr for emacs-devel@gnu.org; Fri, 21 Jun 2024 10:10:20 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sKey3-0000oY-JJ; Fri, 21 Jun 2024 10:10:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=MIME-version:References:Subject:In-Reply-To:To:From: Date; bh=edojEjawxNR5cCjo2ktoWvrFUt3n5EeKHorvpJeRfxU=; b=F9pBwf1Lpb/Idp/Ejiul QDMeWULbdC+p3qWRvCstUs6slAiNL2x3+KI3fsUXpyKP2DwH65bRNaA5EK7LR69tXFFOQ/874tNrH ZqOjkQ8jl17QwtWXSfR088o7ODDBe4LcLYMNK/fG3XTUllR1AoFeGE83kix8vQNQBMMt9JWIP8mQ/ ETtHyW240leFkcymuywh957YHqkI0dYNKILtOB9NiRmCCmohYKluACvaQPVKykjhFYQUz4HxN6ndU 7Ng05wI9DcQ3dkazyVpmaw/aKrhzSpzDTx20del/QKmdXt+egRGDhUEM+XHmEZDATR/UEOo4ZRdAz 3rL7f/1MSTLc7w==; In-Reply-To: (message from Gerd =?iso-8859-1?Q?M=F6llmann?= on Fri, 21 Jun 2024 13:47:12 +0200) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:320404 Archived-At: > From: Gerd Möllmann > Cc: eller.helmut@gmail.com, yantar92@posteo.net, emacs-devel@gnu.org > Date: Fri, 21 Jun 2024 13:47:12 +0200 > > Eli Zaretskii writes: > > >> >> Yes, the SIBPROF handler could at least return early then. > >> > > >> > Perhaps something like this? > >> > >> Not sure. The result of is_busy is only valid at the point in time when > >> it is called. > > > > Are you thinking about what happens when GC is run concurrently? > > Because this is not what happens here, AFAIU. Let's focus on fixing > > the actual issue we see in the backtrace, and consider its possible > > generalizations later. > > > > Are you saying that is_busy could return false in the situation we see > > in the backtrace, i.e. during the entire time MPS processes its > > protection-induced SIGSEGV? > > I'm still not sure. What I'm trying to say is that we need to be sure > that there are no windows left in which things can change. I'd be most > comfortable ATM if the first thing the SIGPROF handler does is check > is_busy and immediately returns, doing nothing. Does that solve the crashes reported here?