From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A436C433E0 for ; Thu, 25 Mar 2021 05:36:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0B87261A1E for ; Thu, 25 Mar 2021 05:36:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229574AbhCYFfZ (ORCPT ); Thu, 25 Mar 2021 01:35:25 -0400 Received: from so254-9.mailgun.net ([198.61.254.9]:49174 "EHLO so254-9.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229493AbhCYFel (ORCPT ); Thu, 25 Mar 2021 01:34:41 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1616650481; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=X12qIuxJ2CSbTarauFRf/LvxSGoKlHCGw1X4+sEEydg=; b=UURPQXfI9jvCIMQScF0UJlLp/hgOj+fuZu7DRuuubZqcOlxXQDnEIZqmIwxHjlkzpNFHXin1 9/rN8BuFkxwbWIxrf5J3Qpnkm2qIj/XZSdPPrk8rCbbsj5f6o/Cu/VRJHK5i1Q7TMj4JOB5y bjTtAmtqj9a8ms6cWTrXC+vtNGM= X-Mailgun-Sending-Ip: 198.61.254.9 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n03.prod.us-east-1.postgun.com with SMTP id 605c20df1d4d56494187cc78 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Thu, 25 Mar 2021 05:34:23 GMT Sender: cang=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id A637BC43465; Thu, 25 Mar 2021 05:34:22 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: cang) by smtp.codeaurora.org (Postfix) with ESMTPSA id 9CA34C433CA; Thu, 25 Mar 2021 05:34:21 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Thu, 25 Mar 2021 13:34:21 +0800 From: Can Guo To: Avri Altman Cc: "James E . J . Bottomley" , "Martin K . Petersen" , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, Bart Van Assche , yongmyung lee , Daejun Park , alim.akhtar@samsung.com, asutoshd@codeaurora.org, Zang Leigang , Avi Shchislowski , Bean Huo , stanley.chu@mediatek.com Subject: Re: [PATCH v6 04/10] scsi: ufshpb: Make eviction depends on region's reads In-Reply-To: <20210322081044.62003-5-avri.altman@wdc.com> References: <20210322081044.62003-1-avri.altman@wdc.com> <20210322081044.62003-5-avri.altman@wdc.com> Message-ID: X-Sender: cang@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-03-22 16:10, Avri Altman wrote: > In host mode, eviction is considered an extreme measure. > verify that the entering region has enough reads, and the exiting > region has much less reads. > > Signed-off-by: Avri Altman > --- > drivers/scsi/ufs/ufshpb.c | 18 +++++++++++++++++- > 1 file changed, 17 insertions(+), 1 deletion(-) > > diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c > index a1519cbb4ce0..5e757220d66a 100644 > --- a/drivers/scsi/ufs/ufshpb.c > +++ b/drivers/scsi/ufs/ufshpb.c > @@ -17,6 +17,7 @@ > #include "../sd.h" > > #define ACTIVATION_THRESHOLD 8 /* 8 IOs */ > +#define EVICTION_THRESHOLD (ACTIVATION_THRESHOLD << 5) /* 256 IOs */ > > /* memory management */ > static struct kmem_cache *ufshpb_mctx_cache; > @@ -1047,6 +1048,13 @@ static struct ufshpb_region > *ufshpb_victim_lru_info(struct ufshpb_lu *hpb) > if (ufshpb_check_srgns_issue_state(hpb, rgn)) > continue; > > + /* > + * in host control mode, verify that the exiting region > + * has less reads > + */ > + if (hpb->is_hcm && rgn->reads > (EVICTION_THRESHOLD >> 1)) > + continue; > + > victim_rgn = rgn; > break; > } > @@ -1219,7 +1227,7 @@ static int ufshpb_issue_map_req(struct ufshpb_lu > *hpb, > > static int ufshpb_add_region(struct ufshpb_lu *hpb, struct > ufshpb_region *rgn) > { > - struct ufshpb_region *victim_rgn; > + struct ufshpb_region *victim_rgn = NULL; > struct victim_select_info *lru_info = &hpb->lru_info; > unsigned long flags; > int ret = 0; > @@ -1246,7 +1254,15 @@ static int ufshpb_add_region(struct ufshpb_lu > *hpb, struct ufshpb_region *rgn) > * It is okay to evict the least recently used region, > * because the device could detect this region > * by not issuing HPB_READ > + * > + * in host control mode, verify that the entering > + * region has enough reads > */ > + if (hpb->is_hcm && rgn->reads < EVICTION_THRESHOLD) { > + ret = -EACCES; > + goto out; > + } > + I cannot understand the logic behind this. A rgn which host chooses to activate, is in INACTIVE state now, if its rgn->reads < 256, then don't activate it. Could you please elaborate? Thanks, Can Guo. > victim_rgn = ufshpb_victim_lru_info(hpb); > if (!victim_rgn) { > dev_warn(&hpb->sdev_ufs_lu->sdev_dev,