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 EA325ECAAD5 for ; Sat, 3 Sep 2022 10:17:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=dNaPwJSGnx7lkzr7bk9vqf/5FP17aD86SLUIbwM0vrs=; b=DFs/METitGBGaS /Dj3ZbMWViPR0GN08sVuGG07oMfNzVIC5aNP/UgA8sxP1RD17UOLn9m+lx65l8EnNX5usJncu34ie iKVE7dNflw6XR2HHXBHCZGI1U6D6ymyizq8bwHKoIgcXxBZ6O5CRjPRLx1Hm31HOggv9TIz7/01OC 7AfmaIxndVTfZKPGSVqd1HkRb06JiW/6qQ0FC2YjxuvXwIOH+PmIhvDabKVDRsL1SApI1RACmwBrI A9Ci0PJUda8Zbg9OezojEb5ROKeGXgABXYZY5q/kEo2SFdJjqKIADSELumn0lZz6S3GXGHzKKA+Nk 0jGC9eLFQ70ebkqfPSqQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oUQCB-008iX7-I6; Sat, 03 Sep 2022 10:16:11 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oUQC7-008i9g-Ha for linux-arm-kernel@lists.infradead.org; Sat, 03 Sep 2022 10:16:10 +0000 X-UUID: 0c036b6bcd874d1495035364e5361131-20220903 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=C7v8EPLTEZmZ1anSY1oDPlwBHyvM0IIQ7mwyVrAfIGI=; b=VcqMn0TJV8maJJiYiReo3rWuElI1R/9vAJigezoDh4G7lXdBjSX1FV50lIJ9HYEOLlC1XhHlQ3u4KnqqAzWNaNIumuaFEV16RaLmvEYvfrvVr8GmAGFG3Akhua0bHAOg4svigEWnuW3Z6vPG+BhqOcpsHx8GxCgyP41cj5YztoI=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.10,REQID:785d41a1-0026-4d82-ad42-45d7284fac06,OB:0,L OB:0,IP:0,URL:0,TC:0,Content:-5,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release _Ham,ACTION:release,TS:-5 X-CID-META: VersionHash:84eae18,CLOUDID:ecd70521-1c20-48a5-82a0-25f9c331906d,C OID:IGNORED,Recheck:0,SF:nil,TC:nil,Content:0,EDM:-3,IP:nil,URL:1,File:nil ,Bulk:nil,QS:nil,BEC:nil,COL:0 X-UUID: 0c036b6bcd874d1495035364e5361131-20220903 Received: from mtkmbs11n1.mediatek.inc [(172.21.101.185)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 851630588; Sat, 03 Sep 2022 03:16:03 -0700 Received: from mtkmbs11n1.mediatek.inc (172.21.101.185) by mtkmbs11n1.mediatek.inc (172.21.101.185) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.792.15; Sat, 3 Sep 2022 17:45:24 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.792.15 via Frontend Transport; Sat, 3 Sep 2022 17:45:24 +0800 From: Lecopzer Chen To: , CC: , , , , , , , , , , , , , , , , , , , , , , , , , Subject: RE: [PATCH v7 0/6] Support hld delayed init based on Pseudo-NMI for arm64 Date: Sat, 3 Sep 2022 17:45:23 +0800 Message-ID: <20220903094523.16002-1-lecopzer.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20220903093415.15850-1-lecopzer.chen@mediatek.com> References: <20220903093415.15850-1-lecopzer.chen@mediatek.com> MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220903_031607_637885_EE1508F1 X-CRM114-Status: GOOD ( 24.20 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Will, Mark Sorry for bothering you, this need to be reviewed by ARM Perf maintainer, could you please help review this pathset or comment about it? Thanks a lot. > Hi Will, Mark > > Could you help review arm parts of this patchset, please? > > For the question mention in both [1] and [2], > > > I'd still like Mark's Ack on this, as the approach you have taken doesn't > > really sit with what he was suggesting. > > > > I also don't understand how all the CPUs get initialised with your patch, > > since the PMU driver will be initialised after SMP is up and running. > > The hardlock detector utilizes the softlockup_start_all() to start all > the cpu on watchdog_allowed_mask, which will do watchdog_nmi_enable() > that registers perf event on each CPUs. > Thus we simply need to retry lockup_detector_init() in a single cpu which > will reconfig and call to softlockup_start_all(). > > Also, the CONFIG_HARDLOCKUP_DETECTOR_PERF selects SOFTLOCKUP_DETECTOR, > IMO, this shows that hardlockup detector supports from softlockup. > > > > We should know whether pNMIs are possible once we've completed > > setup_arch() (and possibly init_IRQ()), long before SMP, so so I reckon > > we should have all the information available once we get to > > lockup_detector_init(), even if that requires some preparatory rework. > > Hardlockup depends on PMU driver , I think the only way is moving > pmu driver at setup_arch() or any point which is earlier than > lockup_detector_init(), and I guess we have to reorganize the architecture > of arm PMU. > > The retry function should benifit all the arch/ not only for arm64. > Any arch who needs to probe its pmu as module can use this without providing > a chance to mess up the setup order. > > > Please let me know if you have any concern about this, thank you > > > [1] https://lore.kernel.org/all/CAFA6WYPPgUvHCpN5=EpJ2Us5h5uVWCbBA59C-YwYQX2ovyVeEw@mail.gmail.com/ > [2] https://lore.kernel.org/linux-arm-kernel/20210419170331.GB31045@willie-the-truck/ > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel