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 35CE43451BB for ; Thu, 18 Dec 2025 13:53:22 +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=1766066005; cv=none; b=niWfO+tTNXAPu/Rwt4qMvbqPgWeYMmKyIYLtEoButQzfRz5zKVB13CJH6uA3SCXnva5zpm1zKUgn17X6qCb12FIc7OfSlTljbypU7YAbuHeSO3SEuta4p+HLVPN9vb22ejduobru8vBDa84imDFwkVO+x3XrkbKL4E4dHXV28G0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766066005; c=relaxed/simple; bh=48AfjUP9f1Z/EE4sgD3IoKNhizsla4ajBR3zpY/9Igk=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ZYYzu42oNzeGg3fQElD5DKza7UG0UatG75RJqYfdoXw6M6DvAGlDh4xGVJRrDsIRfvFVQTKw6WXxF61dRC4ZhY0U5p8Z9l5VivqzmsEZZjrUVPlMcf+lc79DqPVmvo2VEOsWkbcWjTFYOdkJgwlF6qMH5F1rrbKWG+M3ypvrThg= 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 [172.18.224.150]) 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) 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: lhrpeml500011.china.huawei.com (7.191.174.215) To dubpeml100005.china.huawei.com (7.214.146.113) 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); > +}