From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C98FD2673AB; Fri, 14 Feb 2025 16:07:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739549269; cv=none; b=uGlGww18DhXvklDJVc+JeI3CVqLI6BnMGdmrtr2XTATRLxNpla98zgQCsEOqp83iv7ojaoxivto2aJuVmTPKEJeoCewpQ+eryAEToyKz8CahEWLd1HQ/FUYe4d3R+b7EKJcTfR0HjR+yfL5aBTooVDSkVeKA04bNZvjLBbVCYWc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739549269; c=relaxed/simple; bh=Ao7LE4+tbfQL8T8CQHg0pXYdVblJlSaOPMAuV6uc1GI=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=GtXK4GRqzBUv6l3QD3VXe2/K3jBO4m7XgD/G25equV3pz4EEbwclRvGPmAa00h0KvBGOqolQGwPcbjdudSTAMTXQw19QNJL61ARTr8SMoRJ0zWH0aIvCeN3fUZvOfbEAhOjRWgcm8cYTHix58lJjhf89quGF9U5KmoH9zktXuFo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.186.216]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4YvcMH13hZz6H7YC; Sat, 15 Feb 2025 00:04:59 +0800 (CST) Received: from frapeml500008.china.huawei.com (unknown [7.182.85.71]) by mail.maildlp.com (Postfix) with ESMTPS id 7BA1F140A77; Sat, 15 Feb 2025 00:07:27 +0800 (CST) Received: from localhost (10.203.177.66) by frapeml500008.china.huawei.com (7.182.85.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Fri, 14 Feb 2025 17:07:26 +0100 Date: Fri, 14 Feb 2025 16:07:25 +0000 From: Jonathan Cameron To: Robert Richter CC: Alison Schofield , Vishal Verma , Ira Weiny , Dan Williams , Dave Jiang , "Davidlohr Bueso" , , , Gregory Price , "Fabio M. De Francesco" , Terry Bowman Subject: Re: [PATCH v3 07/18] cxl/region: Avoid duplicate call of cxl_find_decoder_early() Message-ID: <20250214160725.0000662f@huawei.com> In-Reply-To: <20250211095349.981096-8-rrichter@amd.com> References: <20250211095349.981096-1-rrichter@amd.com> <20250211095349.981096-8-rrichter@amd.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml500006.china.huawei.com (7.191.161.198) To frapeml500008.china.huawei.com (7.182.85.71) On Tue, 11 Feb 2025 10:53:37 +0100 Robert Richter wrote: > Function cxl_find_decoder_early() is called twice, in > alloc_region_ref() and cxl_rr_alloc_decoder(). Move it out there and out where? I'd make it clear that both these calls are in cxl_port_attach_region() > instead pass the decoder as function argument to both. > > Signed-off-by: Robert Richter > Reviewed-by: Gregory Price > Tested-by: Gregory Price I think this is fine but it's not immediately obvious so a request inline for some more details in this description. > --- > drivers/cxl/core/region.c | 31 +++++++++++++++---------------- > 1 file changed, 15 insertions(+), 16 deletions(-) > > diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c > index 13e3ba984a53..b8201c2faa87 100644 > --- a/drivers/cxl/core/region.c > +++ b/drivers/cxl/core/region.c > @@ -908,7 +908,8 @@ static bool auto_order_ok(struct cxl_port *port, struct cxl_region *cxlr_iter, > > static struct cxl_region_ref * > alloc_region_ref(struct cxl_port *port, struct cxl_region *cxlr, > - struct cxl_endpoint_decoder *cxled) > + struct cxl_endpoint_decoder *cxled, > + struct cxl_decoder *cxld) > { > struct cxl_region_params *p = &cxlr->params; > struct cxl_region_ref *cxl_rr, *iter; > @@ -922,9 +923,6 @@ alloc_region_ref(struct cxl_port *port, struct cxl_region *cxlr, > continue; > > if (test_bit(CXL_REGION_F_AUTO, &cxlr->flags)) { > - struct cxl_decoder *cxld; > - > - cxld = cxl_find_decoder_early(port, cxled, cxlr); This is buried a little deep to be obviously fine to lift out. Seems like it should always have been done outside the xa_for_each() loop in here. So I think this is fine but maybe some more in the patch description is needed to make that point. > if (auto_order_ok(port, iter->region, cxld)) > continue; > } > @@ -1008,17 +1006,9 @@ static int cxl_rr_ep_add(struct cxl_region_ref *cxl_rr, > > static int cxl_rr_alloc_decoder(struct cxl_port *port, struct cxl_region *cxlr, > struct cxl_endpoint_decoder *cxled, > - struct cxl_region_ref *cxl_rr) > + struct cxl_region_ref *cxl_rr, > + struct cxl_decoder *cxld) > { > - struct cxl_decoder *cxld; > - > - cxld = cxl_find_decoder_early(port, cxled, cxlr); > - if (!cxld) { > - dev_dbg(&cxlr->dev, "%s: no decoder available\n", > - dev_name(&port->dev)); > - return -EBUSY; > - } > - > if (cxld->region) { > dev_dbg(&cxlr->dev, "%s: %s already attached to %s\n", > dev_name(&port->dev), dev_name(&cxld->dev), > @@ -1109,7 +1099,16 @@ static int cxl_port_attach_region(struct cxl_port *port, > nr_targets_inc = true; > } > } else { > - cxl_rr = alloc_region_ref(port, cxlr, cxled); > + struct cxl_decoder *cxld; > + > + cxld = cxl_find_decoder_early(port, cxled, cxlr); > + if (!cxld) { > + dev_dbg(&cxlr->dev, "%s: no decoder available\n", > + dev_name(&port->dev)); > + return -EBUSY; > + } > + > + cxl_rr = alloc_region_ref(port, cxlr, cxled, cxld); > if (IS_ERR(cxl_rr)) { > dev_dbg(&cxlr->dev, > "%s: failed to allocate region reference\n", > @@ -1118,7 +1117,7 @@ static int cxl_port_attach_region(struct cxl_port *port, > } > nr_targets_inc = true; > > - rc = cxl_rr_alloc_decoder(port, cxlr, cxled, cxl_rr); > + rc = cxl_rr_alloc_decoder(port, cxlr, cxled, cxl_rr, cxld); > if (rc) > goto out_erase; > }