From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 28293C433B4 for ; Wed, 12 May 2021 13:20:06 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B2B916112D for ; Wed, 12 May 2021 13:20:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B2B916112D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=IA4dHSttk8mhTS9W23M4EOqtqZfIhOXP4o6WmVlER+k=; b=iNkIxpjG8KFFprPHmSinp7a1W pOfAddNhIZV2Kx9DZ0z6QEcuYwLP5Im2WG5YB5YEtqCB3GpKvfQ5OgtACzOG9LVOb5TBvlI7Ur2ha XlPNWya/5c9Y08Z/8C5NQC8+huwOA/m6SJI/0HrW8ZrKT59XmpIm46uJldrMvww1aQTZZL2N2iJwl 1Tx8Tpqh6v9mZlKTncBBujOrcY22EwEiRsIOZ3NPpAn6I4AffS9ReAW+HDI1nx4Ux41mtOdinEzmc 9tzeBKwgENU/J++jG8SKQHHuyUQfsFs+zX2liZLy/SXCj0WcI5Bh2Ez8w+CsoQj9Tny1hh8A6NEMF Ov58tGnpg==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lgom7-002sIl-SB; Wed, 12 May 2021 13:19:44 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lgoip-002rdl-I9 for linux-nvme@desiato.infradead.org; Wed, 12 May 2021 13:16:19 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=Cip8QuGapJKK/MhB2XsoYdZA3zqeZUY0CVfq2URO9Xg=; b=I9bq6HHATiJjZhPNPHbuetFzEG tRlh9gDciQmLIsfWsrtD4IqdtjdqZvyfR9/l8ycOajh0hsZgSJFwwbw93Ujrh57kzKiDRx7qznEe+ McjVaK7cTZfhY2g3GL2MzYcpfQVco0ZoDUgdc2i9/M0S0qT/3yuXzMLP+JxJkyXptE6iAngogIwEs UsvCbNm9cTPSjlMpWhC+8r3kZu/zycKip9/ibXfJZbJCD6WhHUzYwBn4sbWuVXGceSOCklrJWe469 ErohXSD5afx47eKryjsNjGrfeza5pfAZO49t+j4xssN2Spr0/gsOlExTB1q1w/zNpmKvW/s64+zf4 18HgtwZQ==; Received: from [2001:4bb8:198:fbc8:1036:7ab9:f97a:adbc] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lgoin-00AO4l-Ky; Wed, 12 May 2021 13:16:18 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Jeffle Xu , Ming Lei , Damien Le Moal , Keith Busch , Sagi Grimberg , "Wunderlich, Mark" , "Vasudevan, Anil" , linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-nvme@lists.infradead.org, Hannes Reinecke Subject: [PATCH 11/15] block: define 'struct bvec_iter' as packed Date: Wed, 12 May 2021 15:15:41 +0200 Message-Id: <20210512131545.495160-12-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210512131545.495160-1-hch@lst.de> References: <20210512131545.495160-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org From: Ming Lei 'struct bvec_iter' is embedded into 'struct bio', define it as packed so that we can get one extra 4bytes for other uses without expanding bio. 'struct bvec_iter' is often allocated on stack, so making it packed doesn't affect performance. Also I have run io_uring on both nvme/null_blk, and not observe performance effect in this way. Suggested-by: Christoph Hellwig Signed-off-by: Ming Lei Reviewed-by: Hannes Reinecke Signed-off-by: Christoph Hellwig --- include/linux/bvec.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/bvec.h b/include/linux/bvec.h index ff832e698efb..a0c4f41dfc83 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -43,7 +43,7 @@ struct bvec_iter { unsigned int bi_bvec_done; /* number of bytes completed in current bvec */ -}; +} __packed; struct bvec_iter_all { struct bio_vec bv; -- 2.30.2 _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme