From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS3215 2.6.0.0/16 X-Spam-Status: No, score=-4.2 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (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) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 073B71F601 for ; Wed, 7 Dec 2022 17:39:36 +0000 (UTC) Authentication-Results: dcvr.yhbt.net; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.b="AN7O8CVB"; dkim-atps=neutral Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id EEF4A3896C12 for ; Wed, 7 Dec 2022 17:39:34 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org EEF4A3896C12 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1670434775; bh=emg+EsMA9GZUR+hjG7GoDn3PcUDQyy4i9i+j8pQwr0Y=; h=To:Cc:Subject:References:Date:In-Reply-To:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From:Reply-To:From; b=AN7O8CVB06QQnBEcAVprp/5/+0y0grNKpGwsckg+dz9aE+dxtN914iht7f9uUsnN9 NUSy/zTdCbHY54U8A38nD+9IqmkA6HsOrBqACpKm/lKTdxBC5ki5glJFF+ELyVRQS2 H0MxrVOwbDgp3Rd9hSSqccHFsfQNNwZ3farq7b7I= Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 2AF76382E45D for ; Wed, 7 Dec 2022 17:39:15 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 2AF76382E45D Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-27-Xe-uGWiKMXS1MqLf9PkVbQ-1; Wed, 07 Dec 2022 12:39:11 -0500 X-MC-Unique: Xe-uGWiKMXS1MqLf9PkVbQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4836F185A794; Wed, 7 Dec 2022 17:39:11 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.2.16.63]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E97212166B26; Wed, 7 Dec 2022 17:39:09 +0000 (UTC) To: Adhemerval Zanella Netto Cc: Siddhesh Poyarekar , Zack Weinberg via Libc-alpha , Zack Weinberg , DJ Delorie Subject: Re: [RFC] Supporting malloc_usable_size References: <20221124213258.305192-1-siddhesh@gotplt.org> <87sfhyrp19.fsf@igel.home> <87o7smrnlh.fsf@igel.home> <87pmd2rnce.fsf@oldenburg.str.redhat.com> <5758633c-9989-e463-0eb6-33f483439289@owlfolio.org> <87359tpp1m.fsf@oldenburg.str.redhat.com> <874ju7ilcc.fsf@oldenburg.str.redhat.com> <5728d537-fb16-6943-5793-9291f1cabeba@gotplt.org> Date: Wed, 07 Dec 2022 18:39:06 +0100 In-Reply-To: (Adhemerval Zanella Netto's message of "Wed, 7 Dec 2022 13:54:09 -0300") Message-ID: <871qpbgll1.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Florian Weimer via Libc-alpha Reply-To: Florian Weimer Errors-To: libc-alpha-bounces+e=80x24.org@sourceware.org Sender: "Libc-alpha" * Adhemerval Zanella Netto: > Another possibility would to make malloc_usable_size always return the > malloc size argument (although it would add some internal metadata > costs). We can probably implement it with little overhead, even on 32 bit, but a size-class-based allocator will require more drastic changes. Thanks, Florian