From patchwork Wed May 2 23:04:34 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10376775 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5DD8760234 for ; Wed, 2 May 2018 23:04:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 57C14291E8 for ; Wed, 2 May 2018 23:04:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4C06C291F5; Wed, 2 May 2018 23:04:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D21F3291E8 for ; Wed, 2 May 2018 23:04:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2792B6E5CA; Wed, 2 May 2018 23:04:46 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 52A896E5CA for ; Wed, 2 May 2018 23:04:43 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 11576785-1500050 for multiple; Thu, 03 May 2018 00:04:44 +0100 Received: by haswell.alporthouse.com (sSMTP sendmail emulation); Thu, 03 May 2018 00:04:37 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Thu, 3 May 2018 00:04:34 +0100 Message-Id: <20180502230434.26719-2-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180502230434.26719-1-chris@chris-wilson.co.uk> References: <20180502230434.26719-1-chris@chris-wilson.co.uk> X-Originating-IP: 78.156.65.138 X-Country: code=GB country="United Kingdom" ip=78.156.65.138 Subject: [Intel-gfx] [PATCH 2/2] drm/i915: Keep one request in our ring_list X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Don't pre-emptively retire the oldest request in our ring's list if it is the only request. We keep various bits of state alive using the active reference from the request and would rather transfer that state over to a new request rather than the more involved process of retiring and reacquiring it. Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_request.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c index 5acf869f3ca3..75061f9e48eb 100644 --- a/drivers/gpu/drm/i915/i915_request.c +++ b/drivers/gpu/drm/i915/i915_request.c @@ -694,9 +694,9 @@ i915_request_alloc(struct intel_engine_cs *engine, struct i915_gem_context *ctx) goto err_unreserve; /* Move our oldest request to the slab-cache (if not in use!) */ - rq = list_first_entry_or_null(&ring->request_list, - typeof(*rq), ring_link); - if (rq && i915_request_completed(rq)) + rq = list_first_entry(&ring->request_list, typeof(*rq), ring_link); + if (!list_is_last(&rq->ring_link, &ring->request_list) && + i915_request_completed(rq)) i915_request_retire(rq); /*