From patchwork Sat Oct 7 02:28:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sukadev Bhattiprolu X-Patchwork-Id: 822884 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [103.22.144.68]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3y89bw6qHMz9t6W for ; Sat, 7 Oct 2017 13:35:56 +1100 (AEDT) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 3y89bw5XqyzDqy7 for ; Sat, 7 Oct 2017 13:35:56 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from ozlabs.org (bilbo.ozlabs.org [103.22.144.67]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3y89RW2CDPzDqm0 for ; Sat, 7 Oct 2017 13:28:39 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [103.22.144.67]) by bilbo.ozlabs.org (Postfix) with ESMTP id 3y89RV6MZ7z8t08 for ; Sat, 7 Oct 2017 13:28:38 +1100 (AEDT) Received: by ozlabs.org (Postfix) id 3y89RV5094z9t84; Sat, 7 Oct 2017 13:28:38 +1100 (AEDT) Delivered-To: linuxppc-dev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=linux.vnet.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=sukadev@linux.vnet.ibm.com; receiver=) Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3y89RT6ySZz9t7F for ; Sat, 7 Oct 2017 13:28:37 +1100 (AEDT) Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v972Pnqc073161 for ; Fri, 6 Oct 2017 22:28:35 -0400 Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) by mx0a-001b2d01.pphosted.com with ESMTP id 2demj8b09s-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 06 Oct 2017 22:28:35 -0400 Received: from localhost by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 6 Oct 2017 20:28:34 -0600 Received: from b03cxnp08025.gho.boulder.ibm.com (9.17.130.17) by e34.co.us.ibm.com (192.168.1.134) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Fri, 6 Oct 2017 20:28:31 -0600 Received: from b03ledav004.gho.boulder.ibm.com (b03ledav004.gho.boulder.ibm.com [9.17.130.235]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v972SVYi60424400; Fri, 6 Oct 2017 19:28:31 -0700 Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 18B0F78037; Fri, 6 Oct 2017 20:28:31 -0600 (MDT) Received: from suka-w540.usor.ibm.com (unknown [9.70.94.25]) by b03ledav004.gho.boulder.ibm.com (Postfix) with ESMTP id 82B9E7803F; Fri, 6 Oct 2017 20:28:30 -0600 (MDT) From: Sukadev Bhattiprolu To: Michael Ellerman Subject: [PATCH v2 04/18] powerpc/vas: Drop poll_window_cast_out(). Date: Fri, 6 Oct 2017 19:28:04 -0700 X-Mailer: git-send-email 2.7.4 In-Reply-To: <1507343298-27496-1-git-send-email-sukadev@linux.vnet.ibm.com> References: <1507343298-27496-1-git-send-email-sukadev@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17100702-0016-0000-0000-0000079F1222 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007853; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000235; SDB=6.00927531; UDB=6.00466725; IPR=6.00707787; BA=6.00005623; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00017430; XFM=3.00000015; UTC=2017-10-07 02:28:33 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17100702-0017-0000-0000-00003BC1C30F Message-Id: <1507343298-27496-5-git-send-email-sukadev@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-10-07_01:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000 definitions=main-1710070033 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.24 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mikey@neuling.org, linux-kernel@vger.kernel.org, nicholas.piggin@gmail.com, linuxppc-dev@ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Polling for window cast out is listed in the spec, but turns out that it is not strictly necessary and slows down window close. Making it a stub for now. Signed-off-by: Sukadev Bhattiprolu --- arch/powerpc/platforms/powernv/vas-window.c | 34 ++++++++++++++--------------- 1 file changed, 17 insertions(+), 17 deletions(-) diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c index 67ffc5d..8ab8a82 100644 --- a/arch/powerpc/platforms/powernv/vas-window.c +++ b/arch/powerpc/platforms/powernv/vas-window.c @@ -1079,25 +1079,25 @@ static void poll_window_busy_state(struct vas_window *window) } } +/* + * Have the hardware cast a window out of cache and wait for it to + * be completed. + * + * NOTE: It can take a relatively long time to cast the window context + * out of the cache. It is not strictly necessary to cast out if: + * + * - we clear the "Pin Window" bit (so hardware is free to evict) + * + * - we re-initialize the window context when it is reassigned. + * + * We do the former in vas_win_close() and latter in vas_win_open(). + * So, ignoring the cast-out for now. We can add it as needed. If + * casting out becomes necessary we should consider offloading the + * job to a worker thread, so the window close can proceed quickly. + */ static void poll_window_castout(struct vas_window *window) { - int cached; - u64 val; - - /* Cast window context out of the cache */ -retry: - val = read_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL)); - cached = GET_FIELD(VAS_WIN_CACHE_STATUS, val); - if (cached) { - val = 0ULL; - val = SET_FIELD(VAS_CASTOUT_REQ, val, 1); - val = SET_FIELD(VAS_PUSH_TO_MEM, val, 0); - write_hvwc_reg(window, VREG(WIN_CTX_CACHING_CTL), val); - - set_current_state(TASK_UNINTERRUPTIBLE); - schedule_timeout(HZ); - goto retry; - } + /* stub for now */ } /*