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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 433AED6D229 for ; Thu, 18 Dec 2025 13:53:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Subject:CC:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=OfAXsq0+zQ7R2M3GPntXZlpgd+xTHqIuu/wC3TWoI/c=; b=s261LBoS9Y00irGRl9k0gw1Ecb ZZ3jZXtjQnrUoUgLSZXEwxzAClKl/pI0q6GSv+3LXqpMM4pwjv5xjS8YFpe8u84AePkoPdXaVMQWh 3G8r4NCvyD77L+k3rH0Ov13RL4xVKKSUi8JBR/jgAPUfBg3doXaH0BpOdNdq46YZp00NdK4IJDSzb ZKA26qMowB6WPOh1fjonAMdfKtJMLHnWIdZ+d2Um+SIFoWCrtEIjfIRl8Eti3bh6UKYi/9vJkdvoA Ip3kqwJ75p20054Wq91ptN9W3WCrcSlRFHzI7Uhaomjo7vZnReNJ+JcnGrHLhvmAnWdNuKG0Mr9+W j9/ja0nA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vWERe-00000008ZOJ-0fsP; Thu, 18 Dec 2025 13:53:30 +0000 Received: from frasgout.his.huawei.com ([185.176.79.56]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vWERY-00000008ZMy-2dOO for linux-arm-kernel@lists.infradead.org; Thu, 18 Dec 2025 13:53:26 +0000 Received: from mail.maildlp.com (unknown [172.18.224.150]) by frasgout.his.huawei.com (SkyGuard) with ESMTPS id 4dXBv430bRzJ46d3; Thu, 18 Dec 2025 21:52:48 +0800 (CST) Received: from dubpeml100005.china.huawei.com (unknown [7.214.146.113]) by mail.maildlp.com (Postfix) with ESMTPS id 761E240565; Thu, 18 Dec 2025 21:53:19 +0800 (CST) Received: from localhost (10.203.177.15) by dubpeml100005.china.huawei.com (7.214.146.113) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.36; Thu, 18 Dec 2025 13:53:18 +0000 Date: Thu, 18 Dec 2025 13:53:17 +0000 From: Jonathan Cameron To: James Morse CC: , , D Scott Phillips OS , , , , , , Jamie Iles , "Xin Hao" , , , , David Hildenbrand , Dave Martin , Koba Ko , Shanker Donthineni , , , Gavin Shan , Ben Horgan , , , Punit Agrawal Subject: Re: [RFC PATCH 25/38] arm_mpam: resctrl: Add resctrl_arch_rmid_read() and resctrl_arch_reset_rmid() Message-ID: <20251218135317.000004ba@huawei.com> In-Reply-To: <20251205215901.17772-26-james.morse@arm.com> References: <20251205215901.17772-1-james.morse@arm.com> <20251205215901.17772-26-james.morse@arm.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.203.177.15] X-ClientProxiedBy: lhrpeml500011.china.huawei.com (7.191.174.215) To dubpeml100005.china.huawei.com (7.214.146.113) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251218_055324_955264_8435D45E X-CRM114-Status: GOOD ( 20.39 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 5 Dec 2025 21:58:48 +0000 James Morse wrote: > resctrl uses resctrl_arch_rmid_read() to read counters. CDP emulation > means the counter may need reading in three different ways. The same > goes for reset. > > The helpers behind the resctrl_arch_ functions will be re-used for the > ABMC equivalent functions. > > Add the rounding helper for checking monitor values while we're here. > > Signed-off-by: James Morse > --- > drivers/resctrl/mpam_resctrl.c | 154 +++++++++++++++++++++++++++++++++ > include/linux/arm_mpam.h | 5 ++ > 2 files changed, 159 insertions(+) > > diff --git a/drivers/resctrl/mpam_resctrl.c b/drivers/resctrl/mpam_resctrl.c > index a2b238d47117..dc8a819d0976 100644 > --- a/drivers/resctrl/mpam_resctrl.c > +++ b/drivers/resctrl/mpam_resctrl.c > @@ -355,6 +355,160 @@ void resctrl_arch_mon_ctx_free(struct rdt_resource *r, > resctrl_arch_mon_ctx_free_no_wait(evtid, mon_idx); > } > > +static int > +__read_mon(struct mpam_resctrl_mon *mon, struct mpam_component *mon_comp, > + enum mpam_device_features mon_type, > + int mon_idx, > + enum resctrl_conf_type cdp_type, u32 closid, u32 rmid, u64 *val) > +{ > + struct mon_cfg cfg = { }; > + > + if (!mpam_is_enabled()) > + return -EINVAL; > + > + /* Shift closid to account for CDP */ > + closid = resctrl_get_config_index(closid, cdp_type); > + > + if (mon_idx == USE_PRE_ALLOCATED) { > + int mbwu_idx = resctrl_arch_rmid_idx_encode(closid, rmid); > + mon_idx = mon->mbwu_idx_to_mon[mbwu_idx]; > + if (mon_idx == -1) { > + if (mpam_resctrl_abmc_enabled()) { > + /* Report Unassigned */ > + return -ENOENT; > + } > + /* Report Unavailable */ > + return -EINVAL; > + } > + } > + > + cfg.mon = mon_idx; > + cfg.match_pmg = true; > + cfg.partid = closid; > + cfg.pmg = rmid; Maybe use cfg = (struct mon_cfg) { .mon = ... and drop the earlier initialization. }; > + > + if (irqs_disabled()) { > + /* Check if we can access this domain without an IPI */ > + return -EIO; > + } > + > + return mpam_msmon_read(mon_comp, &cfg, mon_type, val); > +} > + > +static int read_mon_cdp_safe(struct mpam_resctrl_mon *mon, struct mpam_component *mon_comp, > + enum mpam_device_features mon_type, > + int mon_idx, u32 closid, u32 rmid, u64 *val) > +{ > + if (cdp_enabled) { > + u64 code_val = 0, data_val = 0; > + int err; > + > + err = __read_mon(mon, mon_comp, mon_type, mon_idx, > + CDP_CODE, closid, rmid, &code_val); > + if (err) > + return err; > + > + err = __read_mon(mon, mon_comp, mon_type, mon_idx, > + CDP_DATA, closid, rmid, &data_val); > + if (!err) > + *val += code_val + data_val; I'd stick to out of line error handling and just spend a couple more lines for readability. if (err) return err; *val += .. return 0; > + return err; > + } > + > + return __read_mon(mon, mon_comp, mon_type, mon_idx, > + CDP_NONE, closid, rmid, val); > +}