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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS 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 ECB06C43382 for ; Tue, 25 Sep 2018 01:10:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 97565204EC for ; Tue, 25 Sep 2018 01:10:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 97565204EC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-pci-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726059AbeIYHPa (ORCPT ); Tue, 25 Sep 2018 03:15:30 -0400 Received: from gate.crashing.org ([63.228.1.57]:49268 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726025AbeIYHPa (ORCPT ); Tue, 25 Sep 2018 03:15:30 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id w8P1A1FB004312; Mon, 24 Sep 2018 20:10:02 -0500 Message-ID: Subject: Re: [PATCHv3 09/10] PCI: Unify device inaccessible From: Benjamin Herrenschmidt To: Keith Busch , Linux PCI , Bjorn Helgaas Cc: Sinan Kaya , Thomas Tai , poza@codeaurora.org, Lukas Wunner , Christoph Hellwig , Mika Westerberg Date: Tue, 25 Sep 2018 11:10:01 +1000 In-Reply-To: <20180918235702.26573-10-keith.busch@intel.com> References: <20180918235702.26573-1-keith.busch@intel.com> <20180918235702.26573-10-keith.busch@intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5 (3.28.5-1.fc28) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tue, 2018-09-18 at 17:57 -0600, Keith Busch wrote: .../... Any reason why you don't do cmpxchg as I originally suggested (sorry I've been away and may have missed some previous emails) > -/* pci_dev priv_flags */ > -#define PCI_DEV_DISCONNECTED 0 > -#define PCI_DEV_ADDED 1 > +/** > + * pci_dev_set_io_state - Set the new error state if possible. > + * > + * @dev - pci device to set new error_state > + * @new - the state we want dev to be in > + * > + * Must be called with device_lock held. This won't work for PowerPC EEH. We will change the state from a readl() so at interrupt time or any other context. We really need the cmpxchg variant. > + * Returns true if state has been changed to the requested state. > + */ > +static inline bool pci_dev_set_io_state(struct pci_dev *dev, > + pci_channel_state_t new) > +{ > + bool changed = false; > + > + device_lock_assert(&dev->dev); > + switch (new) { > + case pci_channel_io_perm_failure: > + switch (dev->error_state) { > + case pci_channel_io_frozen: > + case pci_channel_io_normal: > + case pci_channel_io_perm_failure: > + changed = true; > + break; > + } > + break; > + case pci_channel_io_frozen: > + switch (dev->error_state) { > + case pci_channel_io_frozen: > + case pci_channel_io_normal: > + changed = true; > + break; > + } > + break; > + case pci_channel_io_normal: > + switch (dev->error_state) { > + case pci_channel_io_frozen: > + case pci_channel_io_normal: > + changed = true; > + break; > + } > + break; > + } > + if (changed) > + dev->error_state = new; > + return changed; > +} > > static inline int pci_dev_set_disconnected(struct pci_dev *dev, void *unused) > { > - set_bit(PCI_DEV_DISCONNECTED, &dev->priv_flags); > + device_lock(&dev->dev); > + pci_dev_set_io_state(dev, pci_channel_io_perm_failure); > + device_unlock(&dev->dev); > + > return 0; > } > > static inline bool pci_dev_is_disconnected(const struct pci_dev *dev) > { > - return test_bit(PCI_DEV_DISCONNECTED, &dev->priv_flags); > + return dev->error_state == pci_channel_io_perm_failure; > } > > +/* pci_dev priv_flags */ > +#define PCI_DEV_ADDED 0 > + > static inline void pci_dev_assign_added(struct pci_dev *dev, bool added) > { > assign_bit(PCI_DEV_ADDED, &dev->priv_flags, added); > diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c > index 31e8a4314384..4da2a62b4f77 100644 > --- a/drivers/pci/pcie/err.c > +++ b/drivers/pci/pcie/err.c > @@ -52,9 +52,8 @@ static int report_error_detected(struct pci_dev *dev, > const struct pci_error_handlers *err_handler; > > device_lock(&dev->dev); > - dev->error_state = state; > - > - if (!dev->driver || > + if (!pci_dev_set_io_state(dev, state) || > + !dev->driver || > !dev->driver->err_handler || > !dev->driver->err_handler->error_detected) { > /* > @@ -130,9 +129,8 @@ static int report_resume(struct pci_dev *dev, void *data) > const struct pci_error_handlers *err_handler; > > device_lock(&dev->dev); > - dev->error_state = pci_channel_io_normal; > - > - if (!dev->driver || > + if (!pci_dev_set_io_state(dev, pci_channel_io_normal) || > + !dev->driver || > !dev->driver->err_handler || > !dev->driver->err_handler->resume) > goto out;