From patchwork Mon Mar 19 02:46:30 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sam Bobroff X-Patchwork-Id: 887536 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [103.22.144.68]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 404LGn1Nd3z9sP9 for ; Mon, 19 Mar 2018 13:53:21 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=au1.ibm.com Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 404LGm6WnTzF0wf for ; Mon, 19 Mar 2018 13:53:20 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=au1.ibm.com X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=au1.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=sam.bobroff@au1.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=au1.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 404L753QbPzF0wl for ; Mon, 19 Mar 2018 13:46:41 +1100 (AEDT) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w2J2iSZB048191 for ; Sun, 18 Mar 2018 22:46:39 -0400 Received: from e06smtp11.uk.ibm.com (e06smtp11.uk.ibm.com [195.75.94.107]) by mx0a-001b2d01.pphosted.com with ESMTP id 2gt2ckbw98-1 (version=TLSv1.2 cipher=AES256-SHA256 bits=256 verify=NOT) for ; Sun, 18 Mar 2018 22:46:38 -0400 Received: from localhost by e06smtp11.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Mon, 19 Mar 2018 02:46:34 -0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w2J2kYCS45285382 for ; Mon, 19 Mar 2018 02:46:34 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AC81CAE04D for ; Mon, 19 Mar 2018 02:36:56 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 136ABAE045 for ; Mon, 19 Mar 2018 02:36:56 +0000 (GMT) Received: from ozlabs.au.ibm.com (unknown [9.192.253.14]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP for ; Mon, 19 Mar 2018 02:36:56 +0000 (GMT) Received: from tungsten.ozlabs.ibm.com (unknown [9.192.172.254]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.au.ibm.com (Postfix) with ESMTPSA id 7C2F3A003E for ; Mon, 19 Mar 2018 13:46:32 +1100 (AEDT) Date: Mon, 19 Mar 2018 13:46:30 +1100 From: Sam Bobroff To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v2 2/9] powerpc/eeh: Manage EEH_PE_RECOVERING inside eeh_handle_normal_event() Mail-Followup-To: linuxppc-dev@lists.ozlabs.org References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.3 (2018-01-21) X-TM-AS-GCONF: 00 x-cbid: 18031902-0040-0000-0000-000004429F82 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18031902-0041-0000-0000-000020E5B4BE Message-Id: <163b24ef504d753f4abf1510d9193962bbac32b7.1521427331.git.sam.bobroff@au1.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2018-03-18_16:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1803190032 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Currently the EEH_PE_RECOVERING flag for a PE is managed by both the caller and callee of eeh_handle_normal_event() (among other places not considered here). This is complicated by the fact that the PE may or may not have been invalidated by the call. So move the callee's handling into eeh_handle_normal_event(), which clarifies it and allows the return type to be changed to void (because it no longer needs to indicate at the PE has been invalidated). This should not change behaviour except in eeh_event_handler() where it was previously possible to cause eeh_pe_state_clear() to be called on an invalid PE, which is now avoided. Signed-off-by: Sam Bobroff Reviewed-by: Alexey Kardashevskiy --- arch/powerpc/include/asm/eeh_event.h | 2 +- arch/powerpc/kernel/eeh_driver.c | 29 +++++++++++------------------ arch/powerpc/kernel/eeh_event.c | 2 -- 3 files changed, 12 insertions(+), 21 deletions(-) diff --git a/arch/powerpc/include/asm/eeh_event.h b/arch/powerpc/include/asm/eeh_event.h index 0a168038882d..9884e872686f 100644 --- a/arch/powerpc/include/asm/eeh_event.h +++ b/arch/powerpc/include/asm/eeh_event.h @@ -34,7 +34,7 @@ struct eeh_event { int eeh_event_init(void); int eeh_send_failure_event(struct eeh_pe *pe); void eeh_remove_event(struct eeh_pe *pe, bool force); -bool eeh_handle_normal_event(struct eeh_pe *pe); +void eeh_handle_normal_event(struct eeh_pe *pe); void eeh_handle_special_event(void); #endif /* __KERNEL__ */ diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c index 51b21c97910f..5b7a5ed4db4d 100644 --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -733,7 +733,8 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus, /** * eeh_handle_normal_event - Handle EEH events on a specific PE - * @pe: EEH PE + * @pe: EEH PE - which should not be used after we return, as it may + * have been invalidated. * * Attempts to recover the given PE. If recovery fails or the PE has failed * too many times, remove the PE. @@ -750,10 +751,8 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus, * & devices under this slot, and then finally restarting the device * drivers (which cause a second set of hotplug events to go out to * userspace). - * - * Returns true if @pe should no longer be used, else false. */ -bool eeh_handle_normal_event(struct eeh_pe *pe) +void eeh_handle_normal_event(struct eeh_pe *pe) { struct pci_bus *frozen_bus; struct eeh_dev *edev, *tmp; @@ -765,9 +764,11 @@ bool eeh_handle_normal_event(struct eeh_pe *pe) if (!frozen_bus) { pr_err("%s: Cannot find PCI bus for PHB#%x-PE#%x\n", __func__, pe->phb->global_number, pe->addr); - return false; + return; } + eeh_pe_state_mark(pe, EEH_PE_RECOVERING); + eeh_pe_update_time_stamp(pe); pe->freeze_count++; if (pe->freeze_count > eeh_max_freezes) { @@ -904,7 +905,7 @@ bool eeh_handle_normal_event(struct eeh_pe *pe) pr_info("EEH: Notify device driver to resume\n"); eeh_pe_dev_traverse(pe, eeh_report_resume, NULL); - return false; + goto final; hard_fail: /* @@ -940,12 +941,12 @@ bool eeh_handle_normal_event(struct eeh_pe *pe) pci_lock_rescan_remove(); pci_hp_remove_devices(frozen_bus); pci_unlock_rescan_remove(); - /* The passed PE should no longer be used */ - return true; + return; } } - return false; +final: + eeh_pe_state_clear(pe, EEH_PE_RECOVERING); } /** @@ -1018,15 +1019,7 @@ void eeh_handle_special_event(void) */ if (rc == EEH_NEXT_ERR_FROZEN_PE || rc == EEH_NEXT_ERR_FENCED_PHB) { - /* - * eeh_handle_normal_event() can make the PE stale if it - * determines that the PE cannot possibly be recovered. - * Don't modify the PE state if that's the case. - */ - if (eeh_handle_normal_event(pe)) - continue; - - eeh_pe_state_clear(pe, EEH_PE_RECOVERING); + eeh_handle_normal_event(pe); } else { pci_lock_rescan_remove(); list_for_each_entry(hose, &hose_list, list_node) { diff --git a/arch/powerpc/kernel/eeh_event.c b/arch/powerpc/kernel/eeh_event.c index 872bcfe8f90e..61c9356bf9c9 100644 --- a/arch/powerpc/kernel/eeh_event.c +++ b/arch/powerpc/kernel/eeh_event.c @@ -73,7 +73,6 @@ static int eeh_event_handler(void * dummy) /* We might have event without binding PE */ pe = event->pe; if (pe) { - eeh_pe_state_mark(pe, EEH_PE_RECOVERING); if (pe->type & EEH_PE_PHB) pr_info("EEH: Detected error on PHB#%x\n", pe->phb->global_number); @@ -82,7 +81,6 @@ static int eeh_event_handler(void * dummy) "PHB#%x-PE#%x\n", pe->phb->global_number, pe->addr); eeh_handle_normal_event(pe); - eeh_pe_state_clear(pe, EEH_PE_RECOVERING); } else { eeh_handle_special_event(); }