From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Helmut Eller Newsgroups: gmane.emacs.devel Subject: Re: MPS prstack Date: Mon, 27 May 2024 16:15:34 +0200 Message-ID: <87zfsbl4s9.fsf@gmail.com> References: <87o790qsgm.fsf@gmail.com> <874jap95hi.fsf@gmail.com> <874janpa4m.fsf@gmail.com> <87le3vogt8.fsf@gmail.com> <87a5kbobt4.fsf@gmail.com> <86sey3v5p8.fsf@gnu.org> <87ed9nmnsm.fsf@gmail.com> <86ed9nv1nw.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="15216"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Cc: gerd.moellmann@gmail.com, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon May 27 16:16:31 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 1sBb9L-0003ib-Is for ged-emacs-devel@m.gmane-mx.org; Mon, 27 May 2024 16:16:31 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sBb8p-0004hD-7h; Mon, 27 May 2024 10:15:59 -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 1sBb8c-0004dS-To for emacs-devel@gnu.org; Mon, 27 May 2024 10:15:56 -0400 Original-Received: from mail-wr1-x42e.google.com ([2a00:1450:4864:20::42e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1sBb8T-0006Rq-Uu; Mon, 27 May 2024 10:15:46 -0400 Original-Received: by mail-wr1-x42e.google.com with SMTP id ffacd0b85a97d-354cd8da8b9so1961264f8f.0; Mon, 27 May 2024 07:15:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1716819336; x=1717424136; darn=gnu.org; h=mime-version:user-agent:message-id:date:references:in-reply-to :subject:cc:to:from:from:to:cc:subject:date:message-id:reply-to; bh=29ubFEl+7tuytXhioohIB2h3M2hxGp8OGF189BVoVUc=; b=Vqa+yIiT1im8xA+Y2jvXzPE88M9180Y07YAVSKqXqJMOFaUsEjHKrikgdbpewMVbse 6Kx7MEeMUPNUdgzSprL9RoEJYMkb48Y4nmkF+NQYnKbjSMs8qe65Jjkirm6LGZne8T4/ SNgJGDsj3no2aUA6lwmBMZRaotWvtl/lH4AtBnsXYqkFnO4K2xuJmkY5Iv0GrYkX+CWI sgjU5XlXN2ihSoYS7FsgYTNsnGy24KADA/bqHGsIWoexLMLPzcFzBytxViHe8tEEWJjy Kiml6Wj9O3ZfC8KxitYDATnW8d9Mh9SBWA4pIn86+9H+wd6PaaXVAD+30zBRewZ4uYms Q5kQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1716819336; x=1717424136; h=mime-version:user-agent:message-id:date:references:in-reply-to :subject:cc:to:from:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=29ubFEl+7tuytXhioohIB2h3M2hxGp8OGF189BVoVUc=; b=PzEEEbgGOVVrJnE3om55vQGzqO4huEXDfQxYQs7Yx6yWj7C+dLH4FD9VgJpy6ACIvI rCytKFOxUQotOw+t9bO+NkZ0oe4vV+sXXGmGQRl1fAycTK27mvEBRjTuaMa10RFfsR5T u24mnYWxfl1uWS5UoqmlO4hAsX60yv/pDPeWb93upQdGDL3wp3dv/fsInlbCy0NOBTLc /32n4uUsczopfmKSTrahGKKQztAF7IAcrzpuqswDUiHWrtWqj05fcLaKQI3BVYD4q0e0 DOwC6KQA2GrnvSMS+bRAcWZWaksp5mp0lUwG8XoBaGVy37xj4DD5iPe+Gt+dBcJDrXiK mm4Q== X-Forwarded-Encrypted: i=1; AJvYcCWd5FtHBnH1zGO8Cd6Yuw8SpIgq6Gdp3pDv7BZe2k/jaU4FNS6/MkhyxDC82JAglm3onx26AzYw7SxQHI+QoyHHIZFJ X-Gm-Message-State: AOJu0Yy/FRwqUBuRxY+pxNTPL7wtxine1GAfFItoCslPnWfjohtndv4+ 4QPpKwtfSi9OA5VsOfuP3O0tWkQsmbDBzt0C/WnbYJmujksh0eGgFTeXew== X-Google-Smtp-Source: AGHT+IEk+cJTe4HXzdzzzq6WFaIAZe6mknNFMogLVltIdVwdMP0QZKHi8/mys517u6Z7yqQoAgjPmA== X-Received: by 2002:a5d:524a:0:b0:343:ef64:e0fd with SMTP id ffacd0b85a97d-35527055e10mr6433481f8f.52.1716819335813; Mon, 27 May 2024 07:15:35 -0700 (PDT) Original-Received: from caladan (dial-188233.pool.broadband44.net. [212.46.188.233]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3557a090805sm9059471f8f.48.2024.05.27.07.15.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 May 2024 07:15:35 -0700 (PDT) In-Reply-To: <86ed9nv1nw.fsf@gnu.org> (Eli Zaretskii's message of "Mon, 27 May 2024 16:12:51 +0300") Received-SPF: pass client-ip=2a00:1450:4864:20::42e; envelope-from=eller.helmut@gmail.com; helo=mail-wr1-x42e.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action 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:319610 Archived-At: On Mon, May 27 2024, Eli Zaretskii wrote: >> If print_stack_push increments prstack.sp before initializing >> prstack.stack[prstack.sp], then scan_prstack may read the old value out >> of that slot. > > If we need to make sure that "prstack.stack[prstack.sp++] = e;" is > done atomically, maybe we can use the __atomic builtins (see the node > "__atomic Builtins" in the GCC manual). Yes. I think prstack.stack[prstack.sp] = e; __atomic_store_n (&prstack.sp, prstack.sp + 1, __ATOMIC_SEQ_CST); is quite sufficient.