From patchwork Thu May 3 06:36:50 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10377121 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 8DBFE60541 for ; Thu, 3 May 2018 06:38:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 74FF628CC9 for ; Thu, 3 May 2018 06:38:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 686AC28CE8; Thu, 3 May 2018 06:38:18 +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 228DD28CC9 for ; Thu, 3 May 2018 06:38:18 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A7A4E6E689; Thu, 3 May 2018 06:38:15 +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 A4AC26E696 for ; Thu, 3 May 2018 06:38:13 +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 11578213-1500050 for multiple; Thu, 03 May 2018 07:38:06 +0100 Received: by haswell.alporthouse.com (sSMTP sendmail emulation); Thu, 03 May 2018 07:38:05 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Thu, 3 May 2018 07:36:50 +0100 Message-Id: <20180503063757.22238-4-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180503063757.22238-1-chris@chris-wilson.co.uk> References: <20180503063757.22238-1-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 04/71] 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 Reviewed-by: Tvrtko Ursulin --- 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); /*