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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 2BB5AC4BA21 for ; Wed, 26 Feb 2020 21:28:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA5992072D for ; Wed, 26 Feb 2020 21:28:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727640AbgBZV24 (ORCPT ); Wed, 26 Feb 2020 16:28:56 -0500 Received: from mga05.intel.com ([192.55.52.43]:27794 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727486AbgBZV2z (ORCPT ); Wed, 26 Feb 2020 16:28:55 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Feb 2020 13:28:54 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,489,1574150400"; d="scan'208";a="256472775" Received: from linux.intel.com ([10.54.29.200]) by orsmga002.jf.intel.com with ESMTP; 26 Feb 2020 13:28:53 -0800 Received: from [10.7.201.16] (skuppusw-desk.jf.intel.com [10.7.201.16]) by linux.intel.com (Postfix) with ESMTP id 1C2CA580544; Wed, 26 Feb 2020 13:28:53 -0800 (PST) Reply-To: sathyanarayanan.kuppuswamy@linux.intel.com Subject: Re: [PATCH v15 3/5] PCI/EDR: Export AER, DPC and error recovery functions To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, ashok.raj@intel.com References: <20200226211332.GA147989@google.com> From: Kuppuswamy Sathyanarayanan Organization: Intel Message-ID: <2b37ed9b-3d6f-ea94-4591-86f9d5bbe543@linux.intel.com> Date: Wed, 26 Feb 2020 13:26:09 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20200226211332.GA147989@google.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Bjorn, On 2/26/20 1:13 PM, Bjorn Helgaas wrote: > On Wed, Feb 26, 2020 at 11:30:43AM -0800, Kuppuswamy Sathyanarayanan wrote: >> On 2/25/20 5:02 PM, Bjorn Helgaas wrote: >>> On Thu, Feb 13, 2020 at 10:20:15AM -0800, sathyanarayanan.kuppuswamy@linux.intel.com wrote: >>>> From: Kuppuswamy Sathyanarayanan >>>> ... >>>> +int pci_cleanup_aer_error_status_regs(struct pci_dev *dev) >>>> +{ >>>> + if (pcie_aer_get_firmware_first(dev)) >>>> + return -EIO; >>>> + >>>> + return pci_aer_clear_err_status_regs(dev); >>>> +} >>> We started with these: >>> >>> pci_cleanup_aer_uncorrect_error_status() >>> pci_aer_clear_fatal_status() >>> pci_cleanup_aer_error_status_regs() >>> >>> This was already a mess. They do basically similar things, but the >>> function names are a complete jumble. Let's start with preliminary >>> patches to name them consistently, e.g., >>> >>> pci_aer_clear_nonfatal_status() >>> pci_aer_clear_fatal_status() >>> pci_aer_clear_status() >>> >>> Now, for EDR you eventually add this in edr_handle_event(): >>> >>> edr_handle_event() >>> { >>> ... >>> pci_aer_clear_err_uncor_status(pdev); >>> pci_aer_clear_err_fatal_status(pdev); >>> pci_aer_clear_err_status_regs(pdev); >>> >>> I see that this path needs to clear the status even in the >>> firmware-first case, so you do need some change for that. But >>> pci_aer_clear_err_status_regs() does exactly the same thing as >>> pci_aer_clear_err_uncor_status() and pci_aer_clear_err_fatal_status() >>> plus a little more (clearing PCI_ERR_ROOT_STATUS), so it should be >>> sufficient to just call pci_aer_clear_err_status_regs(). >>> >>> So I don't think you need to make wrappers for >>> pci_aer_clear_nonfatal_status() and pci_aer_clear_fatal_status() at >>> all since they're not needed by the EDR path. >>> >>> You *do* need a wrapper for pci_aer_clear_status(), but instead of >>> just adding random words ("err", "regs") to the name, please name it >>> something like pci_aer_raw_clear_status() as a hint that it skips >>> some sort of check. > What do you think about the above? I agree with your comments.. I will use your recommendation in naming the wrappers I need. > >>> I would split this into a separate patch. This patch contains a bunch >>> of things that aren't really related except that they're needed for >>> EDR. I think it will be more readable if each patch just does one >>> piece of it. >> Ok. I will split it into multiple patches. I just grouped them together >> as a preparatory patch for adding EDR support. > Sounds good. > >>>> diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c >>>> index 99fca8400956..acae12dbf9ff 100644 >>>> --- a/drivers/pci/pcie/dpc.c >>>> +++ b/drivers/pci/pcie/dpc.c >>>> @@ -15,15 +15,9 @@ >>>> #include >>>> #include "portdrv.h" >>>> +#include "dpc.h" >>>> #include "../pci.h" >>>> -struct dpc_dev { >>>> - struct pci_dev *pdev; >>>> - u16 cap_pos; >>>> - bool rp_extensions; >>>> - u8 rp_log_size; >>>> -}; >>> Adding dpc.h shouldn't be in this patch because there's no need for a >>> separate dpc.h file yet -- it's only included this one place. I'm not >>> positive a dpc.h is needed at all -- see comments on patch [4/5]. >> Yes, if we use pdev in dpc functions used by EDR code, we should >> not need it. > I think struct dpc_dev might be more trouble than it's worth. I > attached a possible patch at the end that folds the 25 bits of > DPC-related info into the struct pci_dev and gets rid of struct > dpc_dev completely. I compiled it but haven't tested it. That would solve most of my export issues. Do you want me to add it to my patch list or merge it separately. > >>>> -static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev) >>>> +pci_ers_result_t dpc_reset_link_common(struct dpc_dev *dpc) >>>> { >>> I don't see why you need to split this into dpc_reset_link_common() >>> and dpc_reset_link(). IIUC, you split it so the DPC driver path can >>> supply a pci_dev * via >>> >>> dpc_handler >>> pcie_do_recovery >>> pcie_do_recovery_common(..., NULL, NULL) >>> reset_link(..., NULL, NULL) >>> driver->reset_link(pdev) >>> dpc_reset_link(pdev) >>> dpc = to_dpc_dev(pdev) >> I have split it mainly because of dpc_dev dependency. If we use >> dpc_reset_link(pdev) directly it will try to find related dpc_dev using >> to_dpc_dev() function. But this will not work in FF mode where DPC >> is handled by firmware and hence we will not have DPC pcie_port >> service driver enumerated for this device. > The patch below might help this case. Yes. > >>>> +void dpc_dev_init(struct pci_dev *pdev, struct dpc_dev *dpc) >>>> +{ >>> Can you include the kzalloc() here so we don't have to do the alloc in >>> pci_acpi_add_edr_notifier()? >> Currently dpc driver allocates dpc_dev structure using pcie_port->device >> reference in its devm_alloc* calls. But if we allocate dpc_dev inside >> this function we should use pci_dev->dev reference for it. Is it OK to us >> pci_dev->dev reference for DPC driver allocations ? > I think the patch below would solve this issue too because we don't > need the alloc at all. Agree. > >>> I think there's also a leak there: pci_acpi_add_edr_notifier() >>> kzallocs a struct dpc_dev, but I don't see a corresponding kfree(). >> since we are using devm_allocs, It should be freed when removing >> the PCI device right? > Oh, right, sorry. > > > commit 7fb9f4495711 ("PCI/DPC: Move data to struct pci_dev") > Author: Bjorn Helgaas > Date: Wed Feb 26 08:00:55 2020 -0600 > > PCI/DPC: Move data to struct pci_dev > > > diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c > index e06f42f58d3d..6b116d7fdb89 100644 > --- a/drivers/pci/pcie/dpc.c > +++ b/drivers/pci/pcie/dpc.c > @@ -17,13 +17,6 @@ > #include "portdrv.h" > #include "../pci.h" > > -struct dpc_dev { > - struct pcie_device *dev; > - u16 cap_pos; > - bool rp_extensions; > - u8 rp_log_size; > -}; > - > static const char * const rp_pio_error_string[] = { > "Configuration Request received UR Completion", /* Bit Position 0 */ > "Configuration Request received CA Completion", /* Bit Position 1 */ > @@ -46,63 +39,42 @@ static const char * const rp_pio_error_string[] = { > "Memory Request Completion Timeout", /* Bit Position 18 */ > }; > > -static struct dpc_dev *to_dpc_dev(struct pci_dev *dev) > -{ > - struct device *device; > - > - device = pcie_port_find_device(dev, PCIE_PORT_SERVICE_DPC); > - if (!device) > - return NULL; > - return get_service_data(to_pcie_device(device)); > -} > - > void pci_save_dpc_state(struct pci_dev *dev) > { > - struct dpc_dev *dpc; > struct pci_cap_saved_state *save_state; > u16 *cap; > > if (!pci_is_pcie(dev)) > return; > > - dpc = to_dpc_dev(dev); > - if (!dpc) > - return; > - > save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_DPC); > if (!save_state) > return; > > cap = (u16 *)&save_state->cap.data[0]; > - pci_read_config_word(dev, dpc->cap_pos + PCI_EXP_DPC_CTL, cap); > + pci_read_config_word(dev, dev->dpc_cap + PCI_EXP_DPC_CTL, cap); > } > > void pci_restore_dpc_state(struct pci_dev *dev) > { > - struct dpc_dev *dpc; > struct pci_cap_saved_state *save_state; > u16 *cap; > > if (!pci_is_pcie(dev)) > return; > > - dpc = to_dpc_dev(dev); > - if (!dpc) > - return; > - > save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_DPC); > if (!save_state) > return; > > cap = (u16 *)&save_state->cap.data[0]; > - pci_write_config_word(dev, dpc->cap_pos + PCI_EXP_DPC_CTL, *cap); > + pci_write_config_word(dev, dev->dpc_cap + PCI_EXP_DPC_CTL, *cap); > } > > -static int dpc_wait_rp_inactive(struct dpc_dev *dpc) > +static int dpc_wait_rp_inactive(struct pci_dev *pdev) > { > unsigned long timeout = jiffies + HZ; > - struct pci_dev *pdev = dpc->dev->port; > - u16 cap = dpc->cap_pos, status; > + u16 cap = pdev->dpc_cap, status; > > pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > while (status & PCI_EXP_DPC_RP_BUSY && > @@ -119,15 +91,13 @@ static int dpc_wait_rp_inactive(struct dpc_dev *dpc) > > static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev) > { > - struct dpc_dev *dpc; > u16 cap; > > /* > * DPC disables the Link automatically in hardware, so it has > * already been reset by the time we get here. > */ > - dpc = to_dpc_dev(pdev); > - cap = dpc->cap_pos; > + cap = pdev->dpc_cap; > > /* > * Wait until the Link is inactive, then clear DPC Trigger Status > @@ -135,7 +105,7 @@ static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev) > */ > pcie_wait_for_link(pdev, false); > > - if (dpc->rp_extensions && dpc_wait_rp_inactive(dpc)) > + if (pdev->dpc_rp_extensions && dpc_wait_rp_inactive(pdev)) > return PCI_ERS_RESULT_DISCONNECT; > > pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, > @@ -147,10 +117,9 @@ static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev) > return PCI_ERS_RESULT_RECOVERED; > } > > -static void dpc_process_rp_pio_error(struct dpc_dev *dpc) > +static void dpc_process_rp_pio_error(struct pci_dev *pdev) > { > - struct pci_dev *pdev = dpc->dev->port; > - u16 cap = dpc->cap_pos, dpc_status, first_error; > + u16 cap = pdev->dpc_cap, dpc_status, first_error; > u32 status, mask, sev, syserr, exc, dw0, dw1, dw2, dw3, log, prefix; > int i; > > @@ -175,7 +144,7 @@ static void dpc_process_rp_pio_error(struct dpc_dev *dpc) > first_error == i ? " (First)" : ""); > } > > - if (dpc->rp_log_size < 4) > + if (pdev->dpc_rp_log_size < 4) > goto clear_status; > pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG, > &dw0); > @@ -188,12 +157,12 @@ static void dpc_process_rp_pio_error(struct dpc_dev *dpc) > pci_err(pdev, "TLP Header: %#010x %#010x %#010x %#010x\n", > dw0, dw1, dw2, dw3); > > - if (dpc->rp_log_size < 5) > + if (pdev->dpc_rp_log_size < 5) > goto clear_status; > pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_IMPSPEC_LOG, &log); > pci_err(pdev, "RP PIO ImpSpec Log %#010x\n", log); > > - for (i = 0; i < dpc->rp_log_size - 5; i++) { > + for (i = 0; i < pdev->dpc_rp_log_size - 5; i++) { > pci_read_config_dword(pdev, > cap + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG, &prefix); > pci_err(pdev, "TLP Prefix Header: dw%d, %#010x\n", i, prefix); > @@ -226,10 +195,9 @@ static int dpc_get_aer_uncorrect_severity(struct pci_dev *dev, > > static irqreturn_t dpc_handler(int irq, void *context) > { > + struct pci_dev *pdev = context; > + u16 cap = pdev->dpc_cap, status, source, reason, ext_reason; > struct aer_err_info info; > - struct dpc_dev *dpc = context; > - struct pci_dev *pdev = dpc->dev->port; > - u16 cap = dpc->cap_pos, status, source, reason, ext_reason; > > pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > pci_read_config_word(pdev, cap + PCI_EXP_DPC_SOURCE_ID, &source); > @@ -248,8 +216,8 @@ static irqreturn_t dpc_handler(int irq, void *context) > "reserved error"); > > /* show RP PIO error detail information */ > - if (dpc->rp_extensions && reason == 3 && ext_reason == 0) > - dpc_process_rp_pio_error(dpc); > + if (pdev->dpc_rp_extensions && reason == 3 && ext_reason == 0) > + dpc_process_rp_pio_error(pdev); > else if (reason == 0 && > dpc_get_aer_uncorrect_severity(pdev, &info) && > aer_get_device_error_info(pdev, &info)) { > @@ -266,9 +234,8 @@ static irqreturn_t dpc_handler(int irq, void *context) > > static irqreturn_t dpc_irq(int irq, void *context) > { > - struct dpc_dev *dpc = (struct dpc_dev *)context; > - struct pci_dev *pdev = dpc->dev->port; > - u16 cap = dpc->cap_pos, status; > + struct pci_dev *pdev = context; > + u16 cap = pdev->dpc_cap, status; > > pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); > > @@ -285,7 +252,6 @@ static irqreturn_t dpc_irq(int irq, void *context) > #define FLAG(x, y) (((x) & (y)) ? '+' : '-') > static int dpc_probe(struct pcie_device *dev) > { > - struct dpc_dev *dpc; > struct pci_dev *pdev = dev->port; > struct device *device = &dev->device; > int status; > @@ -294,43 +260,37 @@ static int dpc_probe(struct pcie_device *dev) > if (pcie_aer_get_firmware_first(pdev) && !pcie_ports_dpc_native) > return -ENOTSUPP; > > - dpc = devm_kzalloc(device, sizeof(*dpc), GFP_KERNEL); > - if (!dpc) > - return -ENOMEM; > - > - dpc->cap_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC); > - dpc->dev = dev; > - set_service_data(dev, dpc); > + pdev->dpc_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC); > > status = devm_request_threaded_irq(device, dev->irq, dpc_irq, > dpc_handler, IRQF_SHARED, > - "pcie-dpc", dpc); > + "pcie-dpc", pdev); > if (status) { > pci_warn(pdev, "request IRQ%d failed: %d\n", dev->irq, > status); > return status; > } > > - pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CAP, &cap); > - pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl); > + pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CAP, &cap); > + pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl); > > - dpc->rp_extensions = (cap & PCI_EXP_DPC_CAP_RP_EXT); > - if (dpc->rp_extensions) { > - dpc->rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8; > - if (dpc->rp_log_size < 4 || dpc->rp_log_size > 9) { > + pdev->dpc_rp_extensions = (cap & PCI_EXP_DPC_CAP_RP_EXT) ? 1 : 0; > + if (pdev->dpc_rp_extensions) { > + pdev->dpc_rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8; > + if (pdev->dpc_rp_log_size < 4 || pdev->dpc_rp_log_size > 9) { > pci_err(pdev, "RP PIO log size %u is invalid\n", > - dpc->rp_log_size); > - dpc->rp_log_size = 0; > + pdev->dpc_rp_log_size); > + pdev->dpc_rp_log_size = 0; > } > } > > ctl = (ctl & 0xfff4) | PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN; > - pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl); > + pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl); > > pci_info(pdev, "error containment capabilities: Int Msg #%d, RPExt%c PoisonedTLP%c SwTrigger%c RP PIO Log %d, DL_ActiveErr%c\n", > cap & PCI_EXP_DPC_IRQ, FLAG(cap, PCI_EXP_DPC_CAP_RP_EXT), > FLAG(cap, PCI_EXP_DPC_CAP_POISONED_TLP), > - FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), dpc->rp_log_size, > + FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), pdev->dpc_rp_log_size, > FLAG(cap, PCI_EXP_DPC_CAP_DL_ACTIVE)); > > pci_add_ext_cap_save_buffer(pdev, PCI_EXT_CAP_ID_DPC, sizeof(u16)); > @@ -339,13 +299,12 @@ static int dpc_probe(struct pcie_device *dev) > > static void dpc_remove(struct pcie_device *dev) > { > - struct dpc_dev *dpc = get_service_data(dev); > struct pci_dev *pdev = dev->port; > u16 ctl; > > - pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl); > + pci_read_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, &ctl); > ctl &= ~(PCI_EXP_DPC_CTL_EN_FATAL | PCI_EXP_DPC_CTL_INT_EN); > - pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl); > + pci_write_config_word(pdev, pdev->dpc_cap + PCI_EXP_DPC_CTL, ctl); > } > > static struct pcie_port_service_driver dpcdriver = { > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 3840a541a9de..a0b7e7a53741 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -444,6 +444,11 @@ struct pci_dev { > const struct attribute_group **msi_irq_groups; > #endif > struct pci_vpd *vpd; > +#ifdef CONFIG_PCIE_DPC > + u16 dpc_cap; > + unsigned int dpc_rp_extensions:1; > + u8 dpc_rp_log_size; > +#endif > #ifdef CONFIG_PCI_ATS > union { > struct pci_sriov *sriov; /* PF: SR-IOV info */ > -- Sathyanarayanan Kuppuswamy Linux kernel developer