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 60E4CC43602 for ; Fri, 3 Jul 2026 09:01:09 +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:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=G2El0M6am4JsL+bEkXw1yoY8gU7i68pwJgBLwsg6xg4=; b=zqQK1g6+cLae1HHRKXmGnpRiSN bEqSE1ES19DRq+vEFTz/ZPXEfFTkbvdAUXYMVh/MI4A9Zd0xdmsEtcZIi2Vs0766hm8lrnkELN1En 9fjHjOk8xt36HpSQyJi31ZlhA+Zwvh64q6t9ZHH1frC5ewfkVykWsDVO6qy6/bd+iMYRCcLUBScfD DCqxIwSCgdkpZZWUXCvzb3hUkljnzbGVyBvCvPEhyQGgt6tPBXrDC+C8JFyxqzVRLPEOxF3XUSVWG SypXidQ6V2KurlVtLJkMyPAF7fax7O6dinQIMfG0tVRZOkn6DvP+L/O0BH6vsdGqmtFE0Svg0/nw5 Fhbxpcew==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wfZlc-00000006QlK-4AwF; Fri, 03 Jul 2026 09:01:00 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wfZla-00000006QkS-1qne for linux-arm-kernel@lists.infradead.org; Fri, 03 Jul 2026 09:00:59 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 84C9B1684; Fri, 3 Jul 2026 02:00:52 -0700 (PDT) Received: from [10.211.55.3] (unknown [10.57.73.238]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 58C973F905; Fri, 3 Jul 2026 02:00:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1783069256; bh=FaTU6ZiyPyiPxJG4iwJWWSF1yEgoyNUyWDD0Eltw0Nc=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=lN7tnWTipISpo9m4CaYXRl0gVWPXXDKsf7gAD4vvvnJ/Z4/jkg6moMIhL/WWyqExu 2p0O7hjGjA1NK3XdyTd7HNkneZ+hFShU5sf2L4PtUuBSxpMvEhQkIsRe2eKcPosD3T O+0OMCcSvHl2wEQqYAMeWyW7RCewAh8P1/gyzpJw= Message-ID: Date: Wed, 1 Jul 2026 21:19:28 +0100 MIME-Version: 1.0 User-Agent: Thunderbird Daily Subject: Re: [PATCH v2 07/15] arm_mpam: propagate MSC read errors for state saving functions To: Andre Przywara , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Catalin Marinas , Will Deacon , "Rafael J . Wysocki" , Len Brown , James Morse , Reinette Chatre , Fenghua Yu Cc: Jonathan Cameron , Srivathsa L Rao , Ganapatrao Kulkarni , Trilok Soni , Srinivas Ramana , Niyas Sait , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260702162229.4008659-1-andre.przywara@arm.com> <20260702162229.4008659-8-andre.przywara@arm.com> Content-Language: en-US From: Ben Horgan In-Reply-To: <20260702162229.4008659-8-andre.przywara@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260703_020058_572566_E5D5A2FF X-CRM114-Status: GOOD ( 16.53 ) 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 Hi Andre, On 7/2/26 17:22, Andre Przywara wrote: > Allow the mpam_save_mbwu_state() function to return an error, and > propagate read errors from the lower level up. > > Signed-off-by: Andre Przywara > --- > drivers/resctrl/mpam_devices.c | 47 +++++++++++++++++++++------------- > 1 file changed, 29 insertions(+), 18 deletions(-) > > diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c > index d18c7be86aaa..c50ca0e4f426 100644 > --- a/drivers/resctrl/mpam_devices.c > +++ b/drivers/resctrl/mpam_devices.c > @@ -1773,6 +1773,7 @@ static int mpam_save_mbwu_state(void *arg) > { > int i; > u64 val; > + int ret; > struct mon_cfg *cfg; > u32 cur_flt, cur_ctl, mon_sel; > struct mpam_msc_ris *ris = arg; > @@ -1789,31 +1790,41 @@ static int mpam_save_mbwu_state(void *arg) > mon_sel = FIELD_PREP(MSMON_CFG_MON_SEL_MON_SEL, i) | > FIELD_PREP(MSMON_CFG_MON_SEL_RIS, ris->ris_idx); > mpam_write_monsel_reg(msc, CFG_MON_SEL, mon_sel); > - mpam_read_monsel_reg(msc, CFG_MBWU_FLT, &cur_flt); > - mpam_read_monsel_reg(msc, CFG_MBWU_CTL, &cur_ctl); > - mpam_write_monsel_reg(msc, CFG_MBWU_CTL, 0); > + ret = mpam_read_monsel_reg(msc, CFG_MBWU_FLT, &cur_flt); > + if (!ret) > + ret = mpam_read_monsel_reg(msc, CFG_MBWU_CTL, &cur_ctl); > + if (!ret) > + mpam_write_monsel_reg(msc, CFG_MBWU_CTL, 0); > > - if (mpam_ris_has_mbwu_long_counter(ris)) { > - val = mpam_msc_read_mbwu_l(msc); > - mpam_msc_zero_mbwu_l(msc); > - } else { > - u32 val32; > + if (!ret) { > + if (mpam_ris_has_mbwu_long_counter(ris)) { > + val = mpam_msc_read_mbwu_l(msc); > + mpam_msc_zero_mbwu_l(msc); > + } else { > + u32 val32; > > - mpam_read_monsel_reg(msc, MBWU, &val32); > - val = val32; > - mpam_write_monsel_reg(msc, MBWU, 0); > + ret = mpam_read_monsel_reg(msc, MBWU, &val32); > + if (!ret) { > + val = val32; > + mpam_write_monsel_reg(msc, MBWU, 0); > + } > + } > } > > - cfg->mon = i; > - cfg->pmg = FIELD_GET(MSMON_CFG_x_FLT_PMG, cur_flt); > - cfg->match_pmg = FIELD_GET(MSMON_CFG_x_CTL_MATCH_PMG, cur_ctl); > - cfg->partid = FIELD_GET(MSMON_CFG_x_FLT_PARTID, cur_flt); > - mbwu_state->correction += val; > - mbwu_state->enabled = FIELD_GET(MSMON_CFG_x_CTL_EN, cur_ctl); > + if (!ret && val != MSMON___L_NRDY) { > + cfg->mon = i; > + cfg->pmg = FIELD_GET(MSMON_CFG_x_FLT_PMG, cur_flt); > + cfg->match_pmg = FIELD_GET(MSMON_CFG_x_CTL_MATCH_PMG, cur_ctl); > + cfg->partid = FIELD_GET(MSMON_CFG_x_FLT_PARTID, cur_flt); > + mbwu_state->correction += val; > + mbwu_state->enabled = FIELD_GET(MSMON_CFG_x_CTL_EN, cur_ctl); > + } > mpam_mon_sel_unlock(msc); > + if (ret) > + break; There is a lot of if(!ret) in this loop. Does it not end up cleaner to add an out_unlock label after the loop and jump to that in the failure cases? Thanks, Ben > } > > - return 0; > + return ret; > } > > /*