From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id 0919E38582AE for ; Thu, 4 Aug 2022 15:14:22 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 0919E38582AE 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-18-NCAPy1Q_OiyrqxohZwui9w-1; Thu, 04 Aug 2022 11:14:18 -0400 X-MC-Unique: NCAPy1Q_OiyrqxohZwui9w-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 3C768101A592; Thu, 4 Aug 2022 15:14:18 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.192.37]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 814452166B26; Thu, 4 Aug 2022 15:14:17 +0000 (UTC) From: Florian Weimer To: Siddhesh Poyarekar Cc: libc-alpha@sourceware.org Subject: Re: [PATCH] malloc: Correct the documentation of the top_pad default References: <87wnbojswh.fsf@oldenburg.str.redhat.com> <9ddb2422-47f5-ba9a-e7a3-d9522d80719a@gotplt.org> Date: Thu, 04 Aug 2022 17:14:16 +0200 In-Reply-To: <9ddb2422-47f5-ba9a-e7a3-d9522d80719a@gotplt.org> (Siddhesh Poyarekar's message of "Thu, 4 Aug 2022 10:51:22 -0400") Message-ID: <878ro4jb1z.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 2.78 on 10.11.54.6 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-4.9 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org 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: , X-List-Received-Date: Thu, 04 Aug 2022 15:14:27 -0000 * Siddhesh Poyarekar: > On 2022-08-04 04:48, Florian Weimer via Libc-alpha wrote: >> DEFAULT_TOP_PAD is defined as 131072 in >> sysdeps/generic/malloc-machine.h. > > LGTM, but I wonder if we should tighten this so that it doesn't appear > that DEFAULT_TOP_PAD could be 0 in any of our build configurations. > e.g. we could replace the definition with a #error "define > DEFAULT_TOP_PAD" or something like that to ensure that it's always > defined through malloc-machine.h. What do you think? We could just remove the various #ifdefs, I guess. The other question is whether we can use the constant in the tunable definition file. I haven't investigate any of this. Should I push my change in the meantime? Thanks, Florian