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 7648FC43458 for ; Fri, 10 Jul 2026 14:46:12 +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=zsqosYZcRgfPkeltAq6i/N1Wc6M2UXmlLLWefwz+DaA=; b=xmSg+xS4Ek52A6KHVfmkBULhtR uoyDdn6rG8NEdJTrwOaenBfuSTOl8VwEuUpiUTn2mb8eMfQIohLQQKXsE9MUaCt4zMXF6gu3nfQs4 LzpH/XcSVRY1OO7WTfUgLxW0zbfMotZx0PhD6YiqwMco+1kooDCZhxnCQcSW1K0L/B/LRQWfjqRdK cjoWqf4Zzqf2TXohJE58zPGuFYyJTJ3DY1CeMMxsg8ccL2tW3zQ78Xs54LmyOSSTTuN2JvSPrgWeL dKS0HliA2NwTPnuT/zzp+tAw8uygxEFaexyihdGnML3FdfGh9nGZnRJCIup7fGLGbBq/XgVeTjEf3 V2F5x14g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wiCUP-000000056uV-1B2Y; Fri, 10 Jul 2026 14:46:05 +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 1wiCUL-000000056rD-0vNo for linux-arm-kernel@lists.infradead.org; Fri, 10 Jul 2026 14:46:02 +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 538681F60; Fri, 10 Jul 2026 07:45:56 -0700 (PDT) Received: from e142021.munich.arm.com (e142021.arm.com [10.41.150.148]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ACCA43F7B4; Fri, 10 Jul 2026 07:45:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1783694760; bh=y4YshKpJKf9hQH4Dk+4ONKPsAibk4pSYAqjEPmvDFlw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=H7OVNtLWAmLa4Rvo6npjkySOAERsLGzTVlxkRKMcVJwSycGjqd3Vi6TaFt47/nQgG 0e24pdaQylZwbl3Prles1bLRVZhgZcOOuzvkhN0SeD0uWpIR1WMbAzsmX4JP5O1dvA YMwqhvVIYaXcWUXJQQeTxkkv+Lffnwj2p51NzmGg= From: Andre Przywara To: Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Catalin Marinas , Will Deacon , "Rafael J . Wysocki" , Len Brown , James Morse , Ben Horgan , 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 Subject: [PATCH v3 07/16] arm_mpam: __ris_msmon_read(): get rid of nrdy special handling Date: Fri, 10 Jul 2026 16:45:11 +0200 Message-ID: <20260710144520.917375-8-andre.przywara@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260710144520.917375-1-andre.przywara@arm.com> References: <20260710144520.917375-1-andre.przywara@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-20260710_074601_349199_59385188 X-CRM114-Status: GOOD ( 15.97 ) 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 Although so far MSC accesses couldn't fail, there is one special condition that would create an error: when the MBWU counter wouldn't be able to read a stable value, we were setting bit 63 to mark this value as unstable, and return this as an error later. Now since the functions can return a proper error value, we can get rid of this kludge and use the return value directly. Remove the "nrdy" error flag variable, and assign -EBUSY to "ret" to handle this case. Signed-off-by: Andre Przywara --- drivers/resctrl/mpam_devices.c | 38 +++++++++++++++------------------- 1 file changed, 17 insertions(+), 21 deletions(-) diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index 84a8715464be..530ac0fe97b5 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -1306,7 +1306,6 @@ static void __ris_msmon_read(void *arg) u64 now; int ret; u32 now32; - bool nrdy = false; bool config_mismatch; bool overflow = false; struct mon_read *m = arg; @@ -1371,14 +1370,18 @@ static void __ris_msmon_read(void *arg) switch (m->type) { case mpam_feat_msmon_csu: ret = mpam_read_monsel_reg(msc, CSU, &now32); + if (!ret) { + if ((now32 & MSMON___NRDY)) + ret = -EBUSY; + + if (mpam_has_quirk(IGNORE_CSU_NRDY, msc) && + m->waited_timeout) + ret = 0; + } if (ret) goto out_unlock; - nrdy = now32 & MSMON___NRDY; - now = FIELD_GET(MSMON___VALUE, now32); - - if (mpam_has_quirk(IGNORE_CSU_NRDY, msc) && m->waited_timeout) - nrdy = false; + now = FIELD_GET(MSMON___VALUE, now32); break; case mpam_feat_msmon_mbwu_31counter: case mpam_feat_msmon_mbwu_44counter: @@ -1394,9 +1397,11 @@ static void __ris_msmon_read(void *arg) now = FIELD_GET(MSMON___L_VALUE, now); } else { ret = mpam_read_monsel_reg(msc, MBWU, &now32); + if (!ret && (now32 & MSMON___NRDY)) + ret = -EBUSY; if (ret) goto out_unlock; - nrdy = now32 & MSMON___NRDY; + now = FIELD_GET(MSMON___VALUE, now32); } @@ -1404,9 +1409,6 @@ static void __ris_msmon_read(void *arg) m->type != mpam_feat_msmon_mbwu_63counter) now *= 64; - if (nrdy) - break; - mbwu_state = &ris->mbwu_state[ctx->mon]; if (overflow) @@ -1419,22 +1421,16 @@ static void __ris_msmon_read(void *arg) now += mbwu_state->correction; break; default: - m->err = -EINVAL; + ret = -EINVAL; } - mpam_mon_sel_unlock(msc); - - if (nrdy) - m->err = -EBUSY; - - if (!m->err) - *m->val += now; - - return; out_unlock: mpam_mon_sel_unlock(msc); - m->err = ret; + if (ret) + m->err = ret; + else + *m->val += now; } static int _msmon_read(struct mpam_component *comp, struct mon_read *arg) -- 2.43.0