Re: [PATCH v8 3/5] hisi_acc_vfio_pci: register debugfs for hisilicon migration driver
From: liulongfang
Date: Sat Mar 18 2023 - 05:07:47 EST
On 2023/3/14 23:17, Alex Williamson wrote:
> On Tue, 14 Mar 2023 19:21:29 +0800
> liulongfang <liulongfang@xxxxxxxxxx> wrote:
>
>> On 2023/3/14 19:04, liulongfang wrote:
>>> On 2023/3/11 7:40, Alex Williamson wrote:
>>>> On Fri, 17 Feb 2023 16:48:29 +0800
>>>> Longfang Liu <liulongfang@xxxxxxxxxx> wrote:
>>>>
>>>>> 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.
>>>>>
>>>>> On the basis of the original public debug function, a private debug
>>>>> function is added:
>>>>>
>>>>> mig_data file: used to get the migration data of the live migration device
>>>>> mig_attr file: used to get device attributes of the live migration device
>>>>> debug file: used to test for acquiring and writing device state data
>>>>> for VF device.
>>>>>
>>>>> Signed-off-by: Longfang Liu <liulongfang@xxxxxxxxxx>
>>>>> ---
>>>>> .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 282 ++++++++++++++++++
>>>>> .../vfio/pci/hisilicon/hisi_acc_vfio_pci.h | 11 +
>>>>> 2 files changed, 293 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..a0ecb1cd5707 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 <linux/anon_inodes.h>
>>>>>
>>>>> #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)
>>>>> +{
>>>>> + 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 +1320,265 @@ 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_io(struct vfio_device *vdev)
>>>>> +{
>>>>> + 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;
>>>>> + struct device *dev = vdev->dev;
>>>>> + u64 data;
>>>>> + int ret;
>>>>> +
>>>>> + ret = qm_wait_dev_not_ready(vf_qm);
>>>>> + if (ret)
>>>>> + dev_err(dev, "VF device not ready!\n");
>>>>> +
>>>>> + data = readl(vf_qm->io_base + QM_MB_CMD_SEND_BASE);
>>>>> + dev_info(dev, "debug mailbox val: 0x%llx\n", data);
>>>>> +
>>>>> + return ret;
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vf_debug_resume(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;
>>>>> + struct device *dev = vdev->dev;
>>>>> + int ret;
>>>>> +
>>>>> + ret = vf_qm_state_save(hisi_acc_vdev, migf);
>>>>> + if (ret) {
>>>>> + dev_err(dev, "failed to save device data!\n");
>>>>> + return -EINVAL;
>>>>> + }
>>>>> +
>>>>> + ret = vf_qm_check_match(hisi_acc_vdev, migf);
>>>>> + if (ret) {
>>>>> + dev_err(dev, "failed to match the VF!\n");
>>>>> + return -EINVAL;
>>>>> + }
>>>>> +
>>>>> + ret = vf_qm_load_data(hisi_acc_vdev, migf);
>>>>> + if (ret) {
>>>>> + dev_err(dev, "failed to recover the VF!\n");
>>>>> + return -EINVAL;
>>>>> + }
>>>>> +
>>>>> + vf_qm_fun_reset(&hisi_acc_vdev->vf_qm);
>>>>> + dev_info(dev, "successful to resume device data!\n");
>>>>> +
>>>>> + return 0;
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vf_debug_save(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;
>>>>> + struct device *dev = vdev->dev;
>>>>> + int ret;
>>>>> +
>>>>> + ret = vf_qm_state_save(hisi_acc_vdev, migf);
>>>>> + if (ret) {
>>>>> + dev_err(dev, "failed to save device data!\n");
>>>>> + return -EINVAL;
>>>>> + }
>>>>> + dev_info(dev, "successful to save device data!\n");
>>>>> +
>>>>> + return 0;
>>>>> +}
>>>>> +
>>>>> +static int
>>>>> +hisi_acc_vf_debug_operate(struct vfio_device *vdev, unsigned int cmd)
>>>>> +{
>>>>> + int ret;
>>>>> +
>>>>> + switch (cmd) {
>>>>> + case STATE_SAVE:
>>>>> + ret = hisi_acc_vf_debug_save(vdev);
>>>>> + if (ret)
>>>>> + return ret;
>>>>> + break;
>>>>> + case STATE_RESUME:
>>>>> + ret = hisi_acc_vf_debug_resume(vdev);
>>>>> + if (ret)
>>>>> + return ret;
>>>>> + break;
>>>>> + case RW_IO_TEST:
>>>>> + ret = hisi_acc_vf_debug_io(vdev);
>>>>> + if (ret)
>>>>> + return ret;
>>>>> + break;
>>>>> + default:
>>>>> + return -EINVAL;
>>>>> + }
>>>>> +
>>>>> + return 0;
>>>>> +}
>>>>> +
>>>>> +static int hisi_acc_vf_debug_check(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;
>>>>> + enum vfio_device_mig_state state;
>>>>> +
>>>>> + if (!vdev->mig_ops || !migf) {
>>>>> + dev_err(vdev->dev, "device not support debugfs!\n");
>>>>> + return -EINVAL;
>>>>> + }
>>>>> +
>>>>> + /* If device not opened, the debugfs operation will trigger calltrace */
>>>>> + (void)vdev->mig_ops->migration_get_state(vdev, &state);
>>>>> + if (state == VFIO_DEVICE_STATE_ERROR ||
>>>>> + state == VFIO_DEVICE_STATE_STOP) {
>>>>> + dev_err(vdev->dev, "device not opened!\n");
>>>>> + return -EINVAL;
>>>>> + }
>>>>> +
>>>>> + return 0;
>>>>> +}
>>>>> +
>>>>> +static ssize_t hisi_acc_vf_debug_write(struct file *filp, const char __user *buffer,
>>>>> + size_t count, loff_t *pos)
>>>>> +{
>>>>> + struct vfio_device *vdev = filp->private_data;
>>>>> + char tbuf[VFIO_DEV_DBG_LEN];
>>>>> + unsigned long cmd;
>>>>> + int len, ret;
>>>>> +
>>>>> + if (*pos)
>>>>> + return 0;
>>>>> +
>>>>> + if (count >= VFIO_DEV_DBG_LEN)
>>>>> + return -ENOSPC;
>>>>> +
>>>>> + ret = hisi_acc_vf_debug_check(vdev);
>>>>> + if (ret)
>>>>> + return -EINVAL;
>>>>> +
>>>>> + len = simple_write_to_buffer(tbuf, VFIO_DEV_DBG_LEN - 1,
>>>>> + pos, buffer, count);
>>>>> + if (len < 0 || len > VFIO_DEV_DBG_LEN - 1)
>>>>> + return -EINVAL;
>>>>> + tbuf[len] = '\0';
>>>>> + if (kstrtoul(tbuf, 0, &cmd))
>>>>> + return -EFAULT;
>>>>> +
>>>>> + ret = hisi_acc_vf_debug_operate(vdev, cmd);
>>>>> + if (ret) {
>>>>> + dev_err(vdev->dev, "device debug test failed!\n");
>>>>> + return -EINVAL;
>>>>> + }
>>>>> +
>>>>> + return count;
>>>>> +}
>>>>> +
>>>>> +static const struct file_operations hisi_acc_vf_debug_fops = {
>>>>> + .owner = THIS_MODULE,
>>>>> + .open = simple_open,
>>>>> + .write = hisi_acc_vf_debug_write,
>>>>> +};
>>>>> +
>>>>> +static void seq_print_hex_data(struct seq_file *seq, const void *buf, size_t len)
>>>>> +{
>>>>> +#define HEX_LINE_SIZE 131
>>>>> +#define HEX_ROW_SIZE 16
>>>>> + unsigned char linebuf[HEX_LINE_SIZE];
>>>>> + int i, linelen, remaining = len;
>>>>> + const u8 *ptr = buf;
>>>>> +
>>>>> + for (i = 0; i < len; i += HEX_ROW_SIZE) {
>>>>> + linelen = min(remaining, HEX_ROW_SIZE);
>>>>> + remaining -= HEX_ROW_SIZE;
>>>>> +
>>>>> + hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE, 1,
>>>>> + linebuf, sizeof(linebuf), false);
>>>>> +
>>>>> + seq_printf(seq, "%s%.8x: %s\n", "Mig Data:", i, linebuf);
>>>>> + }
>>>>> +}
>>>>> +
>>>>> +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;
>>>>> + 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_print_hex_data(seq, (unsigned char *)&debug_migf->vf_data,
>>>>> + vf_data_sz);
>>>>> + 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;
>>>>> + 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 device *dev = vdev->dev;
>>>>> + void *migf = NULL;
>>>>> +
>>>>> + if (!debugfs_initialized())
>>>>> + return 0;
>>>>> +
>>>>> + vfio_vf_debugfs_init(vdev);
>>>>> +
>>>>> + migf = kzalloc(sizeof(struct hisi_acc_vf_migration_file), GFP_KERNEL);
>>>>> + if (!migf)
>>>>> + return -ENOMEM;
>>>>> +
>>>>> + hisi_acc_vdev->debug_migf = migf;
>>>>> +
>>>>> + debugfs_create_devm_seqfile(dev, "migration_data", vdev->debug_root,
>>>>> + hisi_acc_vf_data_read);
>>>>> + debugfs_create_devm_seqfile(dev, "migration_attr", vdev->debug_root,
>>>>> + hisi_acc_vf_attr_read);
>>>>> +
>>>>> + debugfs_create_file("migration_debug", 0200, vdev->debug_root,
>>>>> + vdev, &hisi_acc_vf_debug_fops);
>>>>> +
>>>>
>>>> All of these are going to be device specific, right? So do we really
>>>> want a debugfs file structure that looks like:
>>>>
>>>> vfio
>>>> └── migration
>>>> ├── hisi_acc
>>>> │ ├── attr
>>>> │ ├── data
>>>> │ └── debug
>>>> └── state
>>>>
>>>
>>> According to this directory structure, I also need to change.
>>>
>>> Thanks
>>> Longfang.
>>
>> If there are multiple devices participating in live migration, their current directory structure
>> is like this:
>> vfio
>> ├── hisi_acc_1
>> │ ├── attr
>> │ ├── data
>> │ ├── debug
>> │ └── state
>> │
>> └── hisi_acc_2
>> ├── attr
>> ├── data
>> ├── debug
>> └── state
>>
>>
>> If you want to change to the above directory structure, which directory should the
>> ‘state’ file be placed in the case of multiple devices?
>> vfio
>> └─ migration
>> ├── hisi_acc
>> │ ├── attr
>> │ ├── data
>> │ └── debug
>> └── state
>>
>> Like this or other directory structure?
>> vfio
>> └─ migration
>> ├── hisi_acc_1
>> │ ├── attr
>> │ ├── data
>> │ └── debug
>> ├── hisi_acc_2
>> │ ├── attr
>> │ ├── data
>> │ └── debug
>> └── state
>> ├── hisi_acc_1
>> └── hisi_acc_2>
>
> I was thinking:
>
> vfio
> ├── <name1>
> │ └── migration
> │ ├── hisi_acc
> │ │ ├── attr
> │ │ ├── data
> │ │ └── debug
> │ └── state
> └── <name2>
> └── migration
> ├── hisi_acc
> │ ├── attr
> │ ├── data
> │ └── debug
> └── state
>
> My concern is that if {attr,data,debug} have driver specific
> definitions, they should have their own driver specific namespace.
> Thanks,
>
Do <name1> and <name1> refer to dev_name()?
Is the file name "hisi_acc" defined by the driver?
Thanks,
Longfang.
> Alex
>
>
>>>>> + return 0;
>>>>> +}
>>>>> +
>>>>> +static void hisi_acc_vf_debugfs_exit(struct hisi_acc_vf_core_device *hisi_acc_vdev)
>>>>> +{
>>>>> + struct vfio_device *vdev = &hisi_acc_vdev->core_device.vdev;
>>>>> +
>>>>> + if (!debugfs_initialized())
>>>>> + return;
>>>>> +
>>>>> + vfio_vf_debugfs_exit(vdev);
>>>>> + 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);
>>>>> @@ -1416,6 +1692,9 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>>>>> if (IS_ERR(hisi_acc_vdev))
>>>>> return PTR_ERR(hisi_acc_vdev);
>>>>>
>>>>> + if (ops == &hisi_acc_vfio_pci_migrn_ops)
>>>>> + hisi_acc_vfio_debug_init(hisi_acc_vdev);
>>>>> +
>>>>> dev_set_drvdata(&pdev->dev, &hisi_acc_vdev->core_device);
>>>>> ret = vfio_pci_core_register_device(&hisi_acc_vdev->core_device);
>>>>> if (ret)
>>>>> @@ -1423,6 +1702,8 @@ static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device
>>>>> return 0;
>>>>>
>>>>> out_put_vdev:
>>>>> + if (ops == &hisi_acc_vfio_pci_migrn_ops)
>>>>> + hisi_acc_vf_debugfs_exit(hisi_acc_vdev);
>>>>> vfio_put_device(&hisi_acc_vdev->core_device.vdev);
>>>>> return ret;
>>>>> }
>>>>> @@ -1431,6 +1712,7 @@ 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,
>>>>> +};
>>>>> +
>>>>> 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 */
>>>>
>>>> .
>>>>
>>
>
> .
>