From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id B5DA4426C2; Thu, 5 Oct 2023 14:12:17 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 3E2F7402B2; Thu, 5 Oct 2023 14:12:17 +0200 (CEST) Received: from dkmailrelay1.smartsharesystems.com (smartserver.smartsharesystems.com [77.243.40.215]) by mails.dpdk.org (Postfix) with ESMTP id 8D38C402A9 for ; Thu, 5 Oct 2023 14:12:15 +0200 (CEST) Received: from smartserver.smartsharesystems.com (smartserver.smartsharesys.local [192.168.4.10]) by dkmailrelay1.smartsharesystems.com (Postfix) with ESMTP id 5F5F820602; Thu, 5 Oct 2023 14:12:14 +0200 (CEST) Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Subject: RE: [RFC PATCH] eventdev: ensure 16-byte alignment for events Date: Thu, 5 Oct 2023 14:12:10 +0200 X-MimeOLE: Produced By Microsoft Exchange V6.5 Message-ID: <98CBD80474FA8B44BF855DF32C47DC35E9EF01@smartserver.smartshare.dk> In-Reply-To: <20231005115101.12276-1-bruce.richardson@intel.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [RFC PATCH] eventdev: ensure 16-byte alignment for events Thread-Index: Adn3gkiNAE9PQn7BSuWbYz+63+p21gAAgtZQ References: <20231005115101.12276-1-bruce.richardson@intel.com> From: =?iso-8859-1?Q?Morten_Br=F8rup?= To: "Bruce Richardson" , Cc: "Jerin Jacob" X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org > From: Bruce Richardson [mailto:bruce.richardson@intel.com] > Sent: Thursday, 5 October 2023 13.51 ure 16-byte alignment for events >=20 > The event structure in DPDK is 16-bytes in size, and events are > regularly passed as parameters directly rather than being passed as > pointers. To help compiler optimize correctly, we can explicitly = request > 16-byte alignment for events, which means that we should be able > to do aligned vector loads/stores (e.g. with SSE or Neon) when working > with those events. >=20 > Signed-off-by: Bruce Richardson > --- AFAICS it is not specified anywhere that the size of this struct must be = 16 byte. Consider adding this requirement to the struct documentation, and = possibly a static_assert to verify. Acked-by: Morten Br=F8rup