From patchwork Thu Dec 12 16:38:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Dr. David Alan Gilbert" X-Patchwork-Id: 1208712 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="HiQCnbnj"; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 47Yh1h5X8nz9sNH for ; Fri, 13 Dec 2019 04:41:44 +1100 (AEDT) Received: from localhost ([::1]:34852 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ifST8-0003GT-3i for incoming@patchwork.ozlabs.org; Thu, 12 Dec 2019 12:41:42 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:38374) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ifRX8-0007xS-P4 for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:41:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ifRX7-00052j-IL for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:41:46 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:50587 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ifRX7-00051e-EQ for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:41:45 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576168905; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gUB0WF7WUgGKIalrFtHeZRh0OrVfwoA1fO7F1MpTrsc=; b=HiQCnbnjx2HuBST9BakFlgY4UsC/8Tf1xpfvqIwnzGIKMqLbmALbnUUheim+rcz0ASorP2 X6Xn+RztSZq3JcUPqOEp6zdVdwTckOxH3jvu2aDqxoETJR+64ZnpyTJkqhdm1cJZSIcBfQ PZ4d/3sB2d20raSFbki7NrpysUcFca4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-97-_OTNTp86NvSU_VGEmOhtaw-1; Thu, 12 Dec 2019 11:41:43 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D703118B6457 for ; Thu, 12 Dec 2019 16:41:42 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-116-226.ams2.redhat.com [10.36.116.226]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0872B60BE1; Thu, 12 Dec 2019 16:41:41 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com, vgoyal@redhat.com Subject: [PATCH 099/104] virtiofsd: use fuse_buf_writev to replace fuse_buf_write for better performance Date: Thu, 12 Dec 2019 16:38:59 +0000 Message-Id: <20191212163904.159893-100-dgilbert@redhat.com> In-Reply-To: <20191212163904.159893-1-dgilbert@redhat.com> References: <20191212163904.159893-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: _OTNTp86NvSU_VGEmOhtaw-1 X-Mimecast-Spam-Score: 0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: piaojun fuse_buf_writev() only handles the normal write in which src is buffer and dest is fd. Specially if src buffer represents guest physical address that can't be mapped by the daemon process, IO must be bounced back to the VMM to do it by fuse_buf_copy(). Signed-off-by: Jun Piao Suggested-by: Dr. David Alan Gilbert Suggested-by: Stefan Hajnoczi Reviewed-by: Daniel P. Berrangé --- tools/virtiofsd/buffer.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/tools/virtiofsd/buffer.c b/tools/virtiofsd/buffer.c index ae420c70c4..4875473785 100644 --- a/tools/virtiofsd/buffer.c +++ b/tools/virtiofsd/buffer.c @@ -33,9 +33,7 @@ size_t fuse_buf_size(const struct fuse_bufvec *bufv) return size; } -__attribute__((unused)) -static ssize_t fuse_buf_writev(fuse_req_t req, - struct fuse_buf *out_buf, +static ssize_t fuse_buf_writev(struct fuse_buf *out_buf, struct fuse_bufvec *in_buf) { ssize_t res, i, j; @@ -334,12 +332,29 @@ static int fuse_bufvec_advance(struct fuse_bufvec *bufv, size_t len) ssize_t fuse_buf_copy(struct fuse_bufvec *dstv, struct fuse_bufvec *srcv, enum fuse_buf_copy_flags flags) { - size_t copied = 0; + size_t copied = 0, i; if (dstv == srcv) { return fuse_buf_size(dstv); } + /* + * use writev to improve bandwidth when all the + * src buffers already mapped by the daemon + * process + */ + for (i = 0; i < srcv->count; i++) { + if (srcv->buf[i].flags & FUSE_BUF_IS_FD) { + break; + } + } + if ((i == srcv->count) && (dstv->count == 1) && + (dstv->idx == 0) && + (dstv->buf[0].flags & FUSE_BUF_IS_FD)) { + dstv->buf[0].pos += dstv->off; + return fuse_buf_writev(&dstv->buf[0], srcv); + } + for (;;) { const struct fuse_buf *src = fuse_bufvec_current(srcv); const struct fuse_buf *dst = fuse_bufvec_current(dstv);