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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F1173EB64DC for ; Fri, 14 Jul 2023 22:08:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229695AbjGNWIo (ORCPT ); Fri, 14 Jul 2023 18:08:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53682 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229504AbjGNWIm (ORCPT ); Fri, 14 Jul 2023 18:08:42 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 30FB22119 for ; Fri, 14 Jul 2023 15:07:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689372475; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=9z0LuVUeTgjmHXRx0CT3aNWnN0SlXa7ayb6ivAu6Z0U=; b=H5byoxaWs1Fa7NI8tNr0KCb6sHqTAm1MeYnEDE49NaSUqL977qWW19e1jHjHNZBKaiCNsq DXspuIA9k54rDBVcR7xtjmfvF2cVTkNL8zh2xAoA3xSLBgqx6+FR/Y34FpNIdlDpiHg5Vt Z8VaBSXVQvzxWSLQQu+mKXTAFIFyswo= Received: from mail-il1-f200.google.com (mail-il1-f200.google.com [209.85.166.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-478-Enc_iYADNU6ZHq-8x5rHNA-1; Fri, 14 Jul 2023 18:07:54 -0400 X-MC-Unique: Enc_iYADNU6ZHq-8x5rHNA-1 Received: by mail-il1-f200.google.com with SMTP id e9e14a558f8ab-345fe8d0a30so12032025ab.0 for ; Fri, 14 Jul 2023 15:07:54 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689372473; x=1691964473; h=content-transfer-encoding:mime-version:organization:references :in-reply-to:message-id:subject:cc:to:from:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=9z0LuVUeTgjmHXRx0CT3aNWnN0SlXa7ayb6ivAu6Z0U=; b=bOF6r0qrb//NCdTmti1Ym/KI/Qo2IF8/c8ScsWD+CbkN744isqldpHu7VsDBk0FA0D maz+issTzUa15kt8O7kvJxumzw3iPD3oTPzEwKxycYZVG7Fy9gZeB/DPDpeCJUgGmDo2 M3W0tjQVqdN8ZJU0/ZiEfiTohUM+jUuGFCktgdjCGYy4mjJr95Ea8z4JzTT4AVlxGfLp va0lQHB81HWvquoYDCXeS9lrqgTKo5NCaTRXT0h+e5KD1HpNtiwbat3KGTZbwkgAt3e4 OcKGznbjso6qpj6qxJheWcEn2+tqGQxN7pA2S4vn/NaKD8bjsMmsqLOvlJSGm3A19qHQ KhYA== X-Gm-Message-State: ABy/qLY2Hul1PmXz/PqFVLSMgSbSJITDb/L8TEUEaDFpekI9U3QcXEAp 3GixJ1UgJIre9FQMvtGWS6b+bdquXgBxz7Ak66j8nkEJuE9l3saGEu7MLbiefD5pW4UsgvgRurm SDWnmzjXoKGiz+bsmV56s5M6+ X-Received: by 2002:a92:d3ce:0:b0:345:ad81:ecaf with SMTP id c14-20020a92d3ce000000b00345ad81ecafmr5366189ilh.3.1689372473372; Fri, 14 Jul 2023 15:07:53 -0700 (PDT) X-Google-Smtp-Source: APBJJlHp0XdClyrA+yRAiB11ppmOBkvq92RCmA22w4XxQj3BioEs/9avMNimD8zAPxr4ootE/PYk1g== X-Received: by 2002:a92:d3ce:0:b0:345:ad81:ecaf with SMTP id c14-20020a92d3ce000000b00345ad81ecafmr5366175ilh.3.1689372473035; Fri, 14 Jul 2023 15:07:53 -0700 (PDT) Received: from redhat.com ([38.15.36.239]) by smtp.gmail.com with ESMTPSA id t9-20020a056e02060900b00345aaa564a6sm3032694ils.44.2023.07.14.15.07.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 14 Jul 2023 15:07:52 -0700 (PDT) Date: Fri, 14 Jul 2023 16:07:51 -0600 From: Alex Williamson To: liulongfang Cc: , , , , , Subject: Re: [PATCH v11 3/4] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver Message-ID: <20230714160751.551df645.alex.williamson@redhat.com> In-Reply-To: <20230630092457.54902-4-liulongfang@huawei.com> References: <20230630092457.54902-1-liulongfang@huawei.com> <20230630092457.54902-4-liulongfang@huawei.com> Organization: Red Hat MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 30 Jun 2023 17:24:56 +0800 liulongfang wrote: > From: Longfang Liu > > On the debugfs framework of VFIO, if the CONFIG_DEBUG_FS macro is > enabled, the debug function is registered for the live migration driver > of the HiSilicon accelerator device. > > After registering the HiSilicon accelerator device on the debugfs > framework of live migration of vfio, a directory file "hisi_acc" > of debugfs is created, and then three debug function files are > created in this directory: > > data file: used to get the migration data from the driver > attr file: used to get device attributes parameters from the driver > save file: used to read the data of the live migration device and save > it to the driver. > io_test: used to test IO read and write for the driver. > > Signed-off-by: Longfang Liu > --- > .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 182 ++++++++++++++++++ > .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h | 11 ++ > 2 files changed, 193 insertions(+) > > diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c > index a1589947e721..a6f5e94bfaf2 100644 > --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c > +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c > @@ -15,6 +15,7 @@ > #include > > #include "hisi_acc_vfio_pci.h" > +#include "../../vfio.h" > > /* Return 0 on VM acc device ready, -ETIMEDOUT hardware timeout */ > static int qm_wait_dev_not_ready(struct hisi_qm *qm) > @@ -606,6 +607,18 @@ hisi_acc_check_int_state(struct hisi_acc_vf_core_device *hisi_acc_vdev) > } > } > > +static void hisi_acc_vf_migf_save(struct hisi_acc_vf_migration_file *src_migf, > + struct hisi_acc_vf_migration_file *dst_migf) Consider swapping the args to be more consistent with functions like memcpy() where the destination is the first arg and source is the second. > +{ > + if (!dst_migf) > + return; > + > + dst_migf->disabled = false; > + dst_migf->total_length = src_migf->total_length; > + memcpy(&dst_migf->vf_data, &src_migf->vf_data, > + sizeof(struct acc_vf_data)); > +} > + > static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf) > { > mutex_lock(&migf->lock); > @@ -618,12 +631,16 @@ static void hisi_acc_vf_disable_fd(struct hisi_acc_vf_migration_file *migf) > static void hisi_acc_vf_disable_fds(struct hisi_acc_vf_core_device *hisi_acc_vdev) > { > if (hisi_acc_vdev->resuming_migf) { > + hisi_acc_vf_migf_save(hisi_acc_vdev->resuming_migf, > + hisi_acc_vdev->debug_migf); > hisi_acc_vf_disable_fd(hisi_acc_vdev->resuming_migf); > fput(hisi_acc_vdev->resuming_migf->filp); > hisi_acc_vdev->resuming_migf = NULL; > } > > if (hisi_acc_vdev->saving_migf) { > + hisi_acc_vf_migf_save(hisi_acc_vdev->saving_migf, > + hisi_acc_vdev->debug_migf); > hisi_acc_vf_disable_fd(hisi_acc_vdev->saving_migf); > fput(hisi_acc_vdev->saving_migf->filp); > hisi_acc_vdev->saving_migf = NULL; > @@ -1303,6 +1320,164 @@ static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int > return vfio_pci_core_ioctl(core_vdev, cmd, arg); > } > > +static int hisi_acc_vf_debug_check(struct seq_file *seq, struct vfio_device *vdev) > +{ > + struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev); > + struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf; > + > + if (!vdev->mig_ops || !migf) { > + seq_printf(seq, "%s\n", "device not support debugfs!"); "device does not support debugfs"? > + return -EINVAL; > + } > + > + /* If device not opened, the debugfs operation will trigger calltrace */ > + if (!vdev->open_count) { > + seq_printf(seq, "%s\n", "device not opened!"); > + return -EINVAL; > + } What prevents this from racing release of the device? > + > + return 0; > +} > + > +static int hisi_acc_vf_debug_io(struct seq_file *seq, void *data) > +{ > + struct device *vf_dev = seq->private; > + struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev); > + struct vfio_device *vdev = &core_device->vdev; A tab sneaked in here. > + struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev); > + struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm; > + u64 value; > + int ret; > + > + ret = hisi_acc_vf_debug_check(seq, vdev); > + if (ret) > + goto io_err; > + > + ret = qm_wait_dev_not_ready(vf_qm); > + if (ret) { > + seq_printf(seq, "%s\n", "VF device not ready!"); > + goto io_err; > + } > + > + value = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE); > + seq_printf(seq, "%s:0x%llx\n", "debug mailbox val", value); > + > +io_err: > + return 0; A goto that simply returns seems unnecessary vs return at the error condition. Also why don't we return the errno for error cases? Do we even need seq_printf() calls for error cases? > +} > + > +static int hisi_acc_vf_debug_save(struct seq_file *seq, void *data) > +{ > + struct device *vf_dev = seq->private; > + struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev); > + struct vfio_device *vdev = &core_device->vdev; Another tab. > + struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev); > + struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->debug_migf; > + int ret; > + > + ret = hisi_acc_vf_debug_check(seq, vdev); > + if (ret) > + goto save_err; > + > + ret = vf_qm_state_save(hisi_acc_vdev, migf); > + if (ret) { > + seq_printf(seq, "%s\n", "failed to save device data!"); > + goto save_err; > + } > + seq_printf(seq, "%s\n", "successful to save device data!"); > + > +save_err: > + return 0; > +} > + > +static int hisi_acc_vf_data_read(struct seq_file *seq, void *data) > +{ > + struct device *vf_dev = seq->private; > + struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev); > + struct vfio_device *vdev = &core_device->vdev; Tab. > + struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev); > + struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf; > + size_t vf_data_sz = offsetofend(struct acc_vf_data, padding); > + > + if (debug_migf && debug_migf->total_length) > + seq_hex_dump(seq, "Mig Data:", DUMP_PREFIX_OFFSET, 16, 1, > + (unsigned char *)&debug_migf->vf_data, > + vf_data_sz, false); > + else > + seq_printf(seq, "%s\n", "device not migrated!"); > + > + return 0; > +} > + > +static int hisi_acc_vf_attr_read(struct seq_file *seq, void *data) > +{ > + struct device *vf_dev = seq->private; > + struct vfio_pci_core_device *core_device = dev_get_drvdata(vf_dev); > + struct vfio_device *vdev = &core_device->vdev; Tab. > + struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(vdev); > + struct hisi_acc_vf_migration_file *debug_migf = hisi_acc_vdev->debug_migf; > + > + if (debug_migf && debug_migf->total_length) { > + seq_printf(seq, > + "acc device:\n" > + "device state: %d\n" > + "device ready: %u\n" > + "data valid: %d\n" > + "data size: %lu\n", > + hisi_acc_vdev->mig_state, > + hisi_acc_vdev->vf_qm_state, > + debug_migf->disabled, > + debug_migf->total_length); > + } else { > + seq_printf(seq, "%s\n", "device not migrated!"); > + } > + > + return 0; > +} > + > +static int hisi_acc_vfio_debug_init(struct hisi_acc_vf_core_device *hisi_acc_vdev) > +{ > + struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev; > + struct dentry *vfio_dev_migration = NULL; > + struct dentry *vfio_hisi_acc = NULL; > + struct device *dev = vdev->dev; > + void *migf = NULL; > + > + if (!debugfs_initialized()) > + return 0; > + > + migf = kzalloc(sizeof(struct hisi_acc_vf_migration_file), GFP_KERNEL); > + if (!migf) > + return -ENOMEM; > + hisi_acc_vdev->debug_migf = migf; > + > + vfio_dev_migration = debugfs_lookup("migration", vdev->debug_root); > + if (!vfio_dev_migration) { > + dev_err(dev, "failed to lookup migration debugfs file!\n"); > + return -ENODEV; > + } > + > + vfio_hisi_acc = debugfs_create_dir("hisi_acc", vfio_dev_migration); > + debugfs_create_devm_seqfile(dev, "data", vfio_hisi_acc, > + hisi_acc_vf_data_read); > + debugfs_create_devm_seqfile(dev, "attr", vfio_hisi_acc, > + hisi_acc_vf_attr_read); > + debugfs_create_devm_seqfile(dev, "io_test", vfio_hisi_acc, > + hisi_acc_vf_debug_io); > + debugfs_create_devm_seqfile(dev, "save", vfio_hisi_acc, > + hisi_acc_vf_debug_save); > + > + return 0; > +} > + > +static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev) > +{ > + if (!debugfs_initialized()) > + return; > + > + kfree(hisi_acc_vdev->debug_migf); > +} > + > static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev) > { > struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_get_vf_dev(core_vdev); > @@ -1323,6 +1498,7 @@ static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev) > } > > vfio_pci_core_finish_enable(vdev); > + > return 0; > } > > @@ -1420,9 +1596,14 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device > ret = vfio_pci_core_register_device(&hisi_acc_vdev->core_device); > if (ret) > goto out_put_vdev; > + > + if (ops == &hisi_acc_vfio_pci_migrn_ops) > + hisi_acc_vfio_debug_init(hisi_acc_vdev); > return 0; > > out_put_vdev: > + if (ops == &hisi_acc_vfio_pci_migrn_ops) > + hisi_acc_vf_debugfs_exit(hisi_acc_vdev); Why do we need this? There's no case where debug_init occurs before this goto. > vfio_put_device(&hisi_acc_vdev->core_device.vdev); > return ret; > } > @@ -1431,6 +1612,7 @@ static void hisi_acc_vfio_pci_remove(struct pci_dev *pdev) > { > struct hisi_acc_vf_core_device *hisi_acc_vdev = hisi_acc_drvdata(pdev); > > + hisi_acc_vf_debugfs_exit(hisi_acc_vdev); > vfio_pci_core_unregister_device(&hisi_acc_vdev->core_device); > vfio_put_device(&hisi_acc_vdev->core_device.vdev); > } > diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h > index dcabfeec6ca1..ef50b12f018d 100644 > --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h > +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.h > @@ -49,6 +49,14 @@ > #define QM_EQC_DW0 0X8000 > #define QM_AEQC_DW0 0X8020 > > +#define VFIO_DEV_DBG_LEN 256 > + > +enum mig_debug_cmd { > + STATE_SAVE, > + STATE_RESUME, > + RW_IO_TEST, > +}; Unused. Thanks, Alex > + > struct acc_vf_data { > #define QM_MATCH_SIZE offsetofend(struct acc_vf_data, qm_rsv_state) > /* QM match information */ > @@ -113,5 +121,8 @@ struct hisi_acc_vf_core_device { > spinlock_t reset_lock; > struct hisi_acc_vf_migration_file *resuming_migf; > struct hisi_acc_vf_migration_file *saving_migf; > + > + /* For debugfs */ > + struct hisi_acc_vf_migration_file *debug_migf; > }; > #endif /* HISI_ACC_VFIO_PCI_H */