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 X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 941E0C00A89 for ; Mon, 2 Nov 2020 11:47:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 422B7222B9 for ; Mon, 2 Nov 2020 11:47:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="Vr5aHR13" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728637AbgKBLrA (ORCPT ); Mon, 2 Nov 2020 06:47:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728722AbgKBLqd (ORCPT ); Mon, 2 Nov 2020 06:46:33 -0500 Received: from mail-pg1-x543.google.com (mail-pg1-x543.google.com [IPv6:2607:f8b0:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 37D46C0617A6 for ; Mon, 2 Nov 2020 03:46:32 -0800 (PST) Received: by mail-pg1-x543.google.com with SMTP id i7so8636118pgh.6 for ; Mon, 02 Nov 2020 03:46:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=onEvuddY7rjjmRNmF3inPaMsobQ6rmeVGOOE4kPhESY=; b=Vr5aHR13z2KIKtAwzdZ9s6RuU5nLQfx+2eKHmCn96yKknRT+ZskWrmJ8yaTYMU7fWA Duj06UU0FTvBMzrM2Pr/1EXdpd1MkKR4u8DSzE/cXXoIu/RyDBkLJKKUe93TQP2Wm5rf hFSWBvw5Qb1z4J3oRSY2qvEi1w86g4+e8BnVTllmTnVFPa87+8BVL0rk0aw9OP0YW0+D bwK9KSCqGu+AEQ7O7WhQ7SxBEVE5VEzdhEXC3uirBEKqUUTcFVohi3NdE8QMeghI5cde SX0R4CrRZA8D4lI4ATcq/88Bapzxz3tX8ALazIlthY7XTG13blWgKV/JHywhVKn9l2pS e8wA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=onEvuddY7rjjmRNmF3inPaMsobQ6rmeVGOOE4kPhESY=; b=WjHaFILNSHiSHPyhNCCQVrXzHXE5yslBKnEaSbj+RD6JmOR5Ql00MVtjPP71Yov3gm fuUZoNXqPDwPgAnDwEu76u2yOWwPXDNOx7ZlpA/xqYOOz4AoiGRPqEQffdRfMzrPcJD9 JWYT/OyFA9dTRhmr4oY+HEnDKommPuzJfu4cbjPSabN4ohc+xfzpT+7BZD2W0Ss4Cski pmOTY0v9oY9PwshWyM9A8AjSqH34iqQQMT2mC9W2lNReAHiufXP3gRBeRkjzMGxG9ifU lmq10QkTrL+2Ejl3t5VfHCnqVwvXsc7/gJgD0uSpQbtrfED3qAbgHL84vmuUT+fyjArH T3UQ== X-Gm-Message-State: AOAM5329EGVeKge60Cb0uL7fyHmDc7xPgrQYwbeEittjywe2iX6o83Rx gx+I7uy/FT0yPP3PM3vBKHdClw== X-Google-Smtp-Source: ABdhPJz6Klrso4Ngfvn20QS7DmYsk6GOwWNXcIzsTkWC0MaK8geg5GBT9xWeV6BPg/9LlQGCX5EAwA== X-Received: by 2002:a17:90a:d104:: with SMTP id l4mr12488404pju.194.1604317591809; Mon, 02 Nov 2020 03:46:31 -0800 (PST) Received: from localhost.localdomain ([122.173.169.225]) by smtp.gmail.com with ESMTPSA id y5sm14276184pfq.79.2020.11.02.03.46.24 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 02 Nov 2020 03:46:31 -0800 (PST) From: Sumit Garg To: maz@kernel.org, catalin.marinas@arm.com, will@kernel.org, daniel.thompson@linaro.org Cc: linux-arm-kernel@lists.infradead.org, tglx@linutronix.de, jason@lakedaemon.net, linux@armlinux.org.uk, tsbogend@alpha.franken.de, mpe@ellerman.id.au, davem@davemloft.net, mingo@redhat.com, bp@alien8.de, x86@kernel.org, mark.rutland@arm.com, julien.thierry.kdev@gmail.com, dianders@chromium.org, jason.wessel@windriver.com, msys.mizuma@gmail.com, ito-yuichi@fujitsu.com, kgdb-bugreport@lists.sourceforge.net, linux-kernel@vger.kernel.org, Sumit Garg Subject: [PATCH v7 6/7] kgdb: Expose default CPUs roundup fallback mechanism Date: Mon, 2 Nov 2020 17:14:46 +0530 Message-Id: <1604317487-14543-7-git-send-email-sumit.garg@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1604317487-14543-1-git-send-email-sumit.garg@linaro.org> References: <1604317487-14543-1-git-send-email-sumit.garg@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a new API kgdb_smp_call_nmi_hook() to expose default CPUs roundup mechanism to a particular archichecture as a runtime fallback if it detects to not support NMI roundup. Currently such an architecture example is arm64 supporting pseudo NMIs feature which is only available on platforms which have support for GICv3 or later version. Signed-off-by: Sumit Garg --- include/linux/kgdb.h | 12 ++++++++++++ kernel/debug/debug_core.c | 8 +++++++- 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h index 0d6cf64..4190f13 100644 --- a/include/linux/kgdb.h +++ b/include/linux/kgdb.h @@ -200,6 +200,18 @@ kgdb_arch_handle_qxfer_pkt(char *remcom_in_buffer, extern void kgdb_call_nmi_hook(void *ignored); /** + * kgdb_smp_call_nmi_hook - Provide default fallback mechanism to + * round-up CPUs + * + * If you're using the default implementation of kgdb_roundup_cpus() + * this function will be called. And if an arch detects at runtime to + * not support NMI based roundup then it can fallback to default + * mechanism using this API. + */ + +extern void kgdb_smp_call_nmi_hook(void); + +/** * kgdb_roundup_cpus - Get other CPUs into a holding pattern * * On SMP systems, we need to get the attention of the other CPUs diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 1e75a89..ae785d8 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -241,7 +241,7 @@ void __weak kgdb_call_nmi_hook(void *ignored) } NOKPROBE_SYMBOL(kgdb_call_nmi_hook); -void __weak kgdb_roundup_cpus(void) +void kgdb_smp_call_nmi_hook(void) { call_single_data_t *csd; int this_cpu = raw_smp_processor_id(); @@ -273,6 +273,12 @@ void __weak kgdb_roundup_cpus(void) kgdb_info[cpu].rounding_up = false; } } +NOKPROBE_SYMBOL(kgdb_smp_call_nmi_hook); + +void __weak kgdb_roundup_cpus(void) +{ + kgdb_smp_call_nmi_hook(); +} NOKPROBE_SYMBOL(kgdb_roundup_cpus); #endif -- 2.7.4