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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 AD1D9C169C4 for ; Tue, 29 Jan 2019 18:53:09 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 7F8F020844 for ; Tue, 29 Jan 2019 18:53:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="CVJIkGpK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7F8F020844 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ctJZeN3GZY96m/bq5nhkRJtYwoexveOk4fDFkvqszvw=; b=CVJIkGpK+Bz/CH RZQaANVS7qD5i0z7CGBke4wTWKQ9t7DbGmm+ltFERxxlP92VRxHTs+Rq4mHRMlXMVJ2itDa1vp1qk zjIyfh/gyprPI5zZ8UvRdENhr4x3UGH5vzRXIUzRn1wRA1exUqxTNlpeXPU+g3mlcyjYJbWdhDwl+ JaRbaZ9LB9mgOwN5JTN0WddHZvOGSW26WL+cG5hgMq2wRXJ5SyFG578kRDi8pbgt8G+lMCfv999WB 0BeykQIC6GAVA75kLx/12sHy39TCYzmPsvdR46uHT9q/4CA9HmNc8PHjXleSnh+WHlWVRjwPRHoKr vsj771btCqDFBnHoZqgw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1goYVO-0001C2-O4; Tue, 29 Jan 2019 18:53:06 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1goYST-0005qk-Iq for linux-arm-kernel@lists.infradead.org; Tue, 29 Jan 2019 18:50:12 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id EA8C41596; Tue, 29 Jan 2019 10:50:04 -0800 (PST) Received: from eglon.cambridge.arm.com (eglon.cambridge.arm.com [10.1.196.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 48CA03F557; Tue, 29 Jan 2019 10:50:02 -0800 (PST) From: James Morse To: linux-acpi@vger.kernel.org Subject: [PATCH v8 09/26] ACPI / APEI: Generalise the estatus queue's notify code Date: Tue, 29 Jan 2019 18:48:45 +0000 Message-Id: <20190129184902.102850-10-james.morse@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190129184902.102850-1-james.morse@arm.com> References: <20190129184902.102850-1-james.morse@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190129_105005_999833_88FD9BA5 X-CRM114-Status: GOOD ( 14.89 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rafael Wysocki , Tony Luck , Xie XiuQi , Marc Zyngier , Catalin Marinas , Will Deacon , Christoffer Dall , Dongjiu Geng , linux-mm@kvack.org, Borislav Petkov , james.morse@arm.com, Naoya Horiguchi , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Len Brown Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Refactor the estatus queue's pool notification routine from NOTIFY_NMI's handlers. This will allow another notification method to use the estatus queue without duplicating this code. Add rcu_read_lock()/rcu_read_unlock() around the list list_for_each_entry_rcu() walker. These aren't strictly necessary as the whole nmi_enter/nmi_exit() window is a spooky RCU read-side critical section. in_nmi_queue_one_entry() is separate from the rcu-list walker for a later caller that doesn't need to walk a list. Signed-off-by: James Morse Reviewed-by: Punit Agrawal Tested-by: Tyler Baicar --- Changes since v7: * Moved err= onto a separate line to make this more readable * Dropped ghes_ prefix on new static functions * Renamed stuff, 'notify' has an overloaded meaning, Changes since v6: * Removed pool grow/remove code as this is no longer necessary. Changes since v3: * Removed duplicate or redundant paragraphs in commit message. * Fixed the style of a zero check. Changes since v1: * Tidied up _in_nmi_notify_one(). --- drivers/acpi/apei/ghes.c | 65 ++++++++++++++++++++++++++-------------- 1 file changed, 43 insertions(+), 22 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index af3c10f47f20..cb3d88de711f 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -912,37 +912,58 @@ static void __process_error(struct ghes *ghes) #endif } -static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) +static int ghes_in_nmi_queue_one_entry(struct ghes *ghes) { u64 buf_paddr; - struct ghes *ghes; - int sev, ret = NMI_DONE; + int sev; - if (!atomic_add_unless(&ghes_in_nmi, 1, 1)) - return ret; + if (ghes_read_estatus(ghes, &buf_paddr)) { + ghes_clear_estatus(ghes, buf_paddr); + return -ENOENT; + } - list_for_each_entry_rcu(ghes, &ghes_nmi, list) { - if (ghes_read_estatus(ghes, &buf_paddr)) { - ghes_clear_estatus(ghes, buf_paddr); - continue; - } else { - ret = NMI_HANDLED; - } + sev = ghes_severity(ghes->estatus->error_severity); + if (sev >= GHES_SEV_PANIC) { + ghes_print_queued_estatus(); + __ghes_panic(ghes, buf_paddr); + } - sev = ghes_severity(ghes->estatus->error_severity); - if (sev >= GHES_SEV_PANIC) { - ghes_print_queued_estatus(); - __ghes_panic(ghes, buf_paddr); - } + __process_error(ghes); + ghes_clear_estatus(ghes, buf_paddr); - __process_error(ghes); - ghes_clear_estatus(ghes, buf_paddr); + return 0; +} + +static int ghes_in_nmi_spool_from_list(struct list_head *rcu_list) +{ + int err, ret = -ENOENT; + struct ghes *ghes; + + rcu_read_lock(); + list_for_each_entry_rcu(ghes, rcu_list, list) { + err = ghes_in_nmi_queue_one_entry(ghes); + if (!err) + ret = 0; } + rcu_read_unlock(); -#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG - if (ret == NMI_HANDLED) + if (IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG) && !ret) irq_work_queue(&ghes_proc_irq_work); -#endif + + return ret; +} + +static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) +{ + int err, ret = NMI_DONE; + + if (!atomic_add_unless(&ghes_in_nmi, 1, 1)) + return ret; + + err = ghes_in_nmi_spool_from_list(&ghes_nmi); + if (!err) + ret = NMI_HANDLED; + atomic_dec(&ghes_in_nmi); return ret; } -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel