From patchwork Thu May 4 19:53:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 13231743 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id C315AC7EE22 for ; Thu, 4 May 2023 19:59:41 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1puf1Z-0005qC-2s; Thu, 04 May 2023 15:53:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1puf1V-0005pI-Mj for qemu-devel@nongnu.org; Thu, 04 May 2023 15:53:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1puf1T-0006RY-VQ for qemu-devel@nongnu.org; Thu, 04 May 2023 15:53:53 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683230031; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Uh9JsAzQBVO7FYeYzOSkBp65HQ8Exa/aGS/jTv3In5w=; b=SYhlq6RSmkMQ7y7Qx5MHI3mg0+GYdIKoq9IZ/zWGHXxJSerYWLyBITajWgQ9oU77kw90v5 ZRWgT2AyLvkkR/+P3ipvzv56BbPVABoNnKPhA8r7L4bjf3oEBb4oPCokl0M69USDhXuBrx ErobNqfjt45jQQlD1ho6WeareDPLMCY= 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-471-Q3sOoSu5NLOST1Dr08hq8A-1; Thu, 04 May 2023 15:53:48 -0400 X-MC-Unique: Q3sOoSu5NLOST1Dr08hq8A-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D133A811E7B; Thu, 4 May 2023 19:53:46 +0000 (UTC) Received: from localhost (unknown [10.39.192.57]) by smtp.corp.redhat.com (Postfix) with ESMTP id 35F9F1410F29; Thu, 4 May 2023 19:53:45 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Ronnie Sahlberg , Aarushi Mehta , qemu-block@nongnu.org, Paul Durrant , Anthony Perard , Peter Lieven , Stefan Weil , Xie Yongji , Kevin Wolf , Paolo Bonzini , "Michael S. Tsirkin" , Leonardo Bras , Peter Xu , Hanna Reitz , Stefano Stabellini , Richard Henderson , David Woodhouse , Coiby Xu , Eduardo Habkost , Stefano Garzarella , =?utf-8?q?Philippe_Mathieu-Daud?= =?utf-8?q?=C3=A9?= , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Stefan Hajnoczi , Julia Suvorova , xen-devel@lists.xenproject.org, eesposit@redhat.com, Juan Quintela , "Richard W.M. Jones" , Fam Zheng , Marcel Apfelbaum Subject: [PATCH v5 06/21] util/vhost-user-server: rename refcount to in_flight counter Date: Thu, 4 May 2023 15:53:12 -0400 Message-Id: <20230504195327.695107-7-stefanha@redhat.com> In-Reply-To: <20230504195327.695107-1-stefanha@redhat.com> References: <20230504195327.695107-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.161, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org The VuServer object has a refcount field and ref/unref APIs. The name is confusing because it's actually an in-flight request counter instead of a refcount. Normally a refcount destroys the object upon reaching zero. The VuServer counter is used to wake up the vhost-user coroutine when there are no more requests. Avoid confusing by renaming refcount and ref/unref to in_flight and inc/dec. Reviewed-by: Paolo Bonzini Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Stefan Hajnoczi --- include/qemu/vhost-user-server.h | 6 +++--- block/export/vhost-user-blk-server.c | 11 +++++++---- util/vhost-user-server.c | 14 +++++++------- 3 files changed, 17 insertions(+), 14 deletions(-) diff --git a/include/qemu/vhost-user-server.h b/include/qemu/vhost-user-server.h index 25c72433ca..bc0ac9ddb6 100644 --- a/include/qemu/vhost-user-server.h +++ b/include/qemu/vhost-user-server.h @@ -41,7 +41,7 @@ typedef struct { const VuDevIface *vu_iface; /* Protected by ctx lock */ - unsigned int refcount; + unsigned int in_flight; bool wait_idle; VuDev vu_dev; QIOChannel *ioc; /* The I/O channel with the client */ @@ -60,8 +60,8 @@ bool vhost_user_server_start(VuServer *server, void vhost_user_server_stop(VuServer *server); -void vhost_user_server_ref(VuServer *server); -void vhost_user_server_unref(VuServer *server); +void vhost_user_server_inc_in_flight(VuServer *server); +void vhost_user_server_dec_in_flight(VuServer *server); void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx); void vhost_user_server_detach_aio_context(VuServer *server); diff --git a/block/export/vhost-user-blk-server.c b/block/export/vhost-user-blk-server.c index e56b92f2e2..841acb36e3 100644 --- a/block/export/vhost-user-blk-server.c +++ b/block/export/vhost-user-blk-server.c @@ -50,7 +50,10 @@ static void vu_blk_req_complete(VuBlkReq *req, size_t in_len) free(req); } -/* Called with server refcount increased, must decrease before returning */ +/* + * Called with server in_flight counter increased, must decrease before + * returning. + */ static void coroutine_fn vu_blk_virtio_process_req(void *opaque) { VuBlkReq *req = opaque; @@ -68,12 +71,12 @@ static void coroutine_fn vu_blk_virtio_process_req(void *opaque) in_num, out_num); if (in_len < 0) { free(req); - vhost_user_server_unref(server); + vhost_user_server_dec_in_flight(server); return; } vu_blk_req_complete(req, in_len); - vhost_user_server_unref(server); + vhost_user_server_dec_in_flight(server); } static void vu_blk_process_vq(VuDev *vu_dev, int idx) @@ -95,7 +98,7 @@ static void vu_blk_process_vq(VuDev *vu_dev, int idx) Coroutine *co = qemu_coroutine_create(vu_blk_virtio_process_req, req); - vhost_user_server_ref(server); + vhost_user_server_inc_in_flight(server); qemu_coroutine_enter(co); } } diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c index 5b6216069c..1622f8cfb3 100644 --- a/util/vhost-user-server.c +++ b/util/vhost-user-server.c @@ -75,16 +75,16 @@ static void panic_cb(VuDev *vu_dev, const char *buf) error_report("vu_panic: %s", buf); } -void vhost_user_server_ref(VuServer *server) +void vhost_user_server_inc_in_flight(VuServer *server) { assert(!server->wait_idle); - server->refcount++; + server->in_flight++; } -void vhost_user_server_unref(VuServer *server) +void vhost_user_server_dec_in_flight(VuServer *server) { - server->refcount--; - if (server->wait_idle && !server->refcount) { + server->in_flight--; + if (server->wait_idle && !server->in_flight) { aio_co_wake(server->co_trip); } } @@ -192,13 +192,13 @@ static coroutine_fn void vu_client_trip(void *opaque) /* Keep running */ } - if (server->refcount) { + if (server->in_flight) { /* Wait for requests to complete before we can unmap the memory */ server->wait_idle = true; qemu_coroutine_yield(); server->wait_idle = false; } - assert(server->refcount == 0); + assert(server->in_flight == 0); vu_deinit(vu_dev);