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 35B02CA5FD4 for ; Fri, 2 Oct 2026 17:40:50 +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: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ZTh7vCMM021v8lAXSHRZyuGo2XuTLOM60VVyuw9csbw=; b=S+kvoMP2gXMZPH13nzdSO6R7MD TQMiFCIhhfLjb6rLO422LqOD2BMnq8krXTqfSf7vvQMfp2X0lsLcULdSqUW45To/7L/WKBw4x0/8T vPhMeTIdBhDZLdOZcgyoz88FZwK4dZVegDvVamUrHiygu5qpOUnJwH1tTNQTJPiq6I5VtQdmYka5u d45TSLPKOq71x6lyL2kS2F7x4NUsi/BN4wqv7WwZ5Ox0Y8EcbyNEa0Va8tjA8sb9+FY6Qi8gKDLQi 4FVoYd2VO0yxPTlVCUPbcijvFJmZpVK4etQ/r6BoxYzcoRpfBk5vLPpGNM3cMtjs1HVQDCVnxVT5K 850NgTjg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xChFN-0000000CBnY-1g9j; Fri, 02 Oct 2026 17:40:37 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xChFF-0000000CBeB-2AT4 for linux-arm-kernel@bombadil.infradead.org; Fri, 02 Oct 2026 17:40:32 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:MIME-Version :References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=ZTh7vCMM021v8lAXSHRZyuGo2XuTLOM60VVyuw9csbw=; b=Ui/brusK/0n7MX/ue6sqpyFUCs yZP1MjYJ4ZTm1aA1N22XEMfZHmFqMFVmIyujL95zcBUqi4SsJDEPTwzpI/UZLCkya9ICsT1EJHYoT PHJxNYZ9ak/QD/wwSCPmZL5MFEAsOt6FLbOJbmcgo0xqK/KSafq59HX1ARdrdQZwcAFBIzdmKBJYt 8BtK//bKyR0usg0ZJP9WdigRkjdEHxcX02qQDg37oDG6VDCyHSaFencVXXi/GslfLVMRaWEzS4aeU w9QR2yVoLOhDz51Nn+1fijhghD32icivoX8WqAsPq/Zoq2vKLZ4uyF2JQuVBqql6FRgVq05xONuT/ 1Fm/5b3Q==; Received: from foss.arm.com ([217.140.110.172]) by desiato.infradead.org with esmtp (Exim 4.99.2 #2 (Red Hat Linux)) id 1xChFB-00000006BLf-0Vwe for linux-arm-kernel@lists.infradead.org; Fri, 02 Oct 2026 17:40:27 +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 30418169C; Fri, 2 Oct 2026 10:40:20 -0700 (PDT) Received: from eglon.cambridge.arm.com (eglon.cambridge.arm.com [10.2.212.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 734EB3F882; Fri, 2 Oct 2026 10:40:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1790962823; bh=QJUU10lwK5Sw4Tq+neZ4BhNUAsbqgWLbetG9KuRfRK8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CP0IHnmXWJA7+Rh9ymNfpJCMMaxukVF8xCIJ2/Up3nPPUbYL7iW3K+FGx++uHUdpq RjotEd9zgswmiq4muMd3bgVL9oW7gDNCE8y3O3JaRocJpGp5itbRTl8bK+I/d/PUpO QybUNtnu8fdcJURaIOFGzDaL2n1u+s2cKNfYB/VQ= From: James Morse To: linux-arm-kernel@lists.infradead.org Cc: Catalin Marinas , Will Deacon , Ben Horgan , Andre Przywara , Fuad Tabba , Jonathan Cameron , Gavin Shan , James Morse Subject: [PATCH 17/27] arm_mpam: propagate MSC access errors for MBWU counters Date: Fri, 2 Oct 2026 18:39:30 +0100 Message-ID: <20261002173941.292319-18-james.morse@arm.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261002173941.292319-1-james.morse@arm.com> References: <20261002173941.292319-1-james.morse@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261002_184026_286404_2C46A62F X-CRM114-Status: GOOD ( 14.82 ) 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 From: Andre Przywara Allow the mpam_msc_read_mbwu_l() function to return an error, and propagate errors from the lower level up. This also changes the users of this function. Signed-off-by: Andre Przywara Reviewed-by: Jonathan Cameron Reviewed-by: Ben Horgan Reviewed-by: Gavin Shan Tested-by: Gavin Shan # on NVIDIA Grace Hopper [morse: Fixed merge conflicts in mpam_save_mbwu_state() and __ris_msmon_read()] Signed-off-by: James Morse --- drivers/resctrl/mpam_devices.c | 31 ++++++++++++++++++++++--------- 1 file changed, 22 insertions(+), 9 deletions(-) diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index a5365b56b1e7..c573fe08ce01 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -1139,8 +1139,9 @@ struct mon_read { bool waited_timeout; }; -static u64 mpam_msc_read_mbwu_l(struct mpam_msc *msc) +static int mpam_msc_read_mbwu_l(struct mpam_msc *msc, u64 *res) { + int ret; int retry = 3; u32 mbwu_l_low; u32 mbwu_l_high1, mbwu_l_high2; @@ -1150,20 +1151,30 @@ static u64 mpam_msc_read_mbwu_l(struct mpam_msc *msc) WARN_ON_ONCE((MSMON_MBWU_L + sizeof(u64)) > msc->mapped_hwpage_sz); WARN_ON_ONCE(!cpumask_test_cpu(smp_processor_id(), &msc->accessibility)); - __mpam_read_reg(msc, MSMON_MBWU_L + 4, &mbwu_l_high2); + ret = __mpam_read_reg(msc, MSMON_MBWU_L + 4, &mbwu_l_high2); + if (ret) + return ret; + do { mbwu_l_high1 = mbwu_l_high2; - __mpam_read_reg(msc, MSMON_MBWU_L, &mbwu_l_low); - __mpam_read_reg(msc, MSMON_MBWU_L + 4, &mbwu_l_high2); + ret = __mpam_read_reg(msc, MSMON_MBWU_L, &mbwu_l_low); + if (ret) + return ret; + ret = __mpam_read_reg(msc, MSMON_MBWU_L + 4, &mbwu_l_high2); + if (ret) + return ret; retry--; } while (mbwu_l_high1 != mbwu_l_high2 && retry > 0); - if (mbwu_l_high1 == mbwu_l_high2) - return ((u64)mbwu_l_high1 << 32) | mbwu_l_low; + if (mbwu_l_high1 == mbwu_l_high2) { + *res = ((u64)mbwu_l_high1 << 32) | mbwu_l_low; + } else { + pr_warn("Failed to read a stable value\n"); + *res = MSMON___L_NRDY; + } - pr_warn("Failed to read a stable value\n"); - return MSMON___L_NRDY; + return 0; } static void mpam_msc_zero_mbwu_l(struct mpam_msc *msc) @@ -1381,7 +1392,9 @@ static void __ris_msmon_read_locked(struct mon_read *m) case mpam_feat_msmon_mbwu_44counter: case mpam_feat_msmon_mbwu_63counter: if (m->type != mpam_feat_msmon_mbwu_31counter) { - now = mpam_msc_read_mbwu_l(msc); + m->err = mpam_msc_read_mbwu_l(msc, &now); + if (m->err) + return; nrdy = now & MSMON___L_NRDY; if (m->type == mpam_feat_msmon_mbwu_63counter) -- 2.53.0