From patchwork Thu May 3 06:37:00 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10377145 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 EAFB2603B4 for ; Thu, 3 May 2018 06:38:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DBD81251F9 for ; Thu, 3 May 2018 06:38:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D086428E2B; Thu, 3 May 2018 06:38:41 +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 894AA251F9 for ; Thu, 3 May 2018 06:38:41 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B4FE76E6C5; Thu, 3 May 2018 06:38:40 +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 054BC6E6C2 for ; Thu, 3 May 2018 06:38:38 +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 11578235-1500050 for multiple; Thu, 03 May 2018 07:38:30 +0100 Received: by haswell.alporthouse.com (sSMTP sendmail emulation); Thu, 03 May 2018 07:38:28 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Thu, 3 May 2018 07:37:00 +0100 Message-Id: <20180503063757.22238-14-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> MIME-Version: 1.0 X-Originating-IP: 78.156.65.138 X-Country: code=GB country="United Kingdom" ip=78.156.65.138 Subject: [Intel-gfx] [PATCH 14/71] drm/i915: Combine tasklet_kill and tasklet_disable 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: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP Ideally, we want to atomically flush and disable the tasklet before resetting the GPU. At present, we rely on being the only part to touch our tasklet and serialisation of the reset process to ensure that we can suspend the tasklet from the mix of reset/wedge pathways. In this patch, we move the tasklet abuse into its own function and tweak it such that we only do a synchronous operation the first time it is disabled around the reset. This allows us to avoid the sync inside a softirq context in subsequent patches. Signed-off-by: Chris Wilson Cc: Mika Kuoppala Cc: Michał Winiarski CC: Michel Thierry Cc: Jeff McGee --- drivers/gpu/drm/i915/intel_lrc.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 0c7733d6eb01..a60c3afd0adb 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -1842,6 +1842,16 @@ static int gen9_init_render_ring(struct intel_engine_cs *engine) return 0; } +static void tasklet_kill_and_disable(struct tasklet_struct *t) +{ + if (!atomic_read(&t->count)) + tasklet_kill(t); + + if (atomic_inc_return(&t->count) == 1) + tasklet_unlock_wait(t); + smp_mb(); +} + static struct i915_request * execlists_reset_prepare(struct intel_engine_cs *engine) { @@ -1866,9 +1876,7 @@ execlists_reset_prepare(struct intel_engine_cs *engine) * common case of recursively being called from set-wedged from inside * i915_reset. */ - if (!atomic_read(&execlists->tasklet.count)) - tasklet_kill(&execlists->tasklet); - tasklet_disable(&execlists->tasklet); + tasklet_kill_and_disable(&execlists->tasklet); /* * We want to flush the pending context switches, having disabled