From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-2943005-1517591370-2-12820502008663105033 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1517591370; b=esIlaYTWM+m3f+gE7MaXwH570lckgrGM1fr6eKOVH8NU27w O4Fq23TvygxnvHg4iATBKaAHWdInNp2ipwvUKjHTOqRpanXmmpr2CGq1j86QXAO8 2wd8KgYYzYvp5jDp2zUINuh+NL+3/nmlJFRZc/uLFR08WVRxKeE6vTcTmP1o6+qL Fu34qlkGoHWd8Pe+AIVpbIBVsAtfcVYf6WBzCk85LWrravpWI6w0CkJbMYsttpqc eq971IhQ+tgVjAZEmr9BIGvazRwvTQMpDuInlChg6u3cI+mmcKDZINuvy6C1Lu9p /hxBaYDacg+P/wwlb8epqPyNBP0/xRl698tRKIQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1517591370; bh=cTVkBUdUQGziARIu+eHk6/Gh18 4WKcVI00U8KAnwJXQ=; b=AE56GlPFdPde/tKaibnAHIQ47ndKmBNDHHAZy4gHTM 5WOmvxunMYe6dELuczRaDrlGbyKjTDHMD+tCfVyN4r+l9/tyUv9KqcEJeMx68qAf ItLB+Ca/QfFv4a+Roi/wwHHfR3/xAVg0MIaWV0LsolAANJQ+RN5tBpJ5oPCokFvP v7EC/PQlOgEFL8yg2o45ul2rBGDTlAyCJSlQ2Cdwk6DW6Vtkso/oBmht2eRKxYUm 8zPQcYa8aMvhA/h1EgDcjcZ49Z0nhSepwKku5BYGLSh6B4exUuDhd8QlWh9mB9Jb THMaY0DM2X81GxvYraOQKysPqzqfc4vwkx+oXKfd2efw== ARC-Authentication-Results: i=1; mx4.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx4.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752770AbeBBRJ1 (ORCPT ); Fri, 2 Feb 2018 12:09:27 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:37910 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753074AbeBBRJW (ORCPT ); Fri, 2 Feb 2018 12:09:22 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Harald Freudenberger , Martin Schwidefsky , Sasha Levin Subject: [PATCH 4.14 053/156] s390/zcrypt: Fix wrong comparison leading to strange load balancing Date: Fri, 2 Feb 2018 17:57:14 +0100 Message-Id: <20180202140842.670298822@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180202140840.242829545@linuxfoundation.org> References: <20180202140840.242829545@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Harald Freudenberger [ Upstream commit 0b0882672640ced4deeebf84da0b88b6389619c4 ] The function to decide if one zcrypt queue is better than another one compared two pointers instead of comparing the values where the pointers refer to. So within the same zcrypt card when load of each queue was equal just one queue was used. This effect only appears on relatively lite load, typically with one thread applications. This patch fixes the wrong comparison and now the counters show that requests are balanced equally over all available queues within the cards. There is no performance improvement coming with this fix. As long as the queue depth for an APQN queue is not touched, processing is not faster when requests are spread over queues within the same card hardware. So this fix only beautifies the lszcrypt counter printouts. Signed-off-by: Harald Freudenberger Signed-off-by: Martin Schwidefsky Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/s390/crypto/zcrypt_api.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/s390/crypto/zcrypt_api.c +++ b/drivers/s390/crypto/zcrypt_api.c @@ -218,8 +218,8 @@ static inline bool zcrypt_queue_compare( weight += atomic_read(&zq->load); pref_weight += atomic_read(&pref_zq->load); if (weight == pref_weight) - return &zq->queue->total_request_count > - &pref_zq->queue->total_request_count; + return zq->queue->total_request_count > + pref_zq->queue->total_request_count; return weight > pref_weight; }