Re: [PATCH v8 16/20] PCI/AER: Convert aer_get_device_error_info(), aer_print_error() to index

[Sathyanarayanan Kuppuswamy]

On 5/22/25 4:21 PM, Bjorn Helgaas wrote:

From: Bjorn Helgaas <bhelg...@google.com>

Previously aer_get_device_error_info() and aer_print_error() took a pointer
to struct aer_err_info and a pointer to a pci_dev.  Typically the pci_dev
was one of the elements of the aer_err_info.dev[] array (DPC was an
exception, where the dev[] array was unused).

Convert aer_get_device_error_info() and aer_print_error() to take an index
into the aer_err_info.dev[] array instead.  A future patch will add
per-device ratelimit information, so the index makes it convenient to find
the ratelimit associated with the device.

To accommodate DPC, set info->dev[0] to the DPC port before using these
interfaces.

Signed-off-by: Bjorn Helgaas <bhelg...@google.com>
---

Reviewed-by: Kuppuswamy Sathyanarayanan 
<sathyanarayanan.kuppusw...@linux.intel.com>

  drivers/pci/pci.h      |  4 ++--
  drivers/pci/pcie/aer.c | 33 +++++++++++++++++++++++----------
  drivers/pci/pcie/dpc.c |  8 ++++++--
  3 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 1a9bfc708757..e1a28215967f 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -605,8 +605,8 @@ struct aer_err_info {
        struct pcie_tlp_log tlp;        /* TLP Header */
  };

-int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info);

-void aer_print_error(struct pci_dev *dev, struct aer_err_info *info);
+int aer_get_device_error_info(struct aer_err_info *info, int i);
+void aer_print_error(struct aer_err_info *info, int i);

int pcie_read_tlp_log(struct pci_dev *dev, int where, int where2,

                      unsigned int tlp_len, bool flit,
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 787a953fb331..237741e66d28 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -705,12 +705,18 @@ static void aer_print_source(struct pci_dev *dev, struct 
aer_err_info *info,
                 found ? "" : " (no details found");
  }

-void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)

+void aer_print_error(struct aer_err_info *info, int i)
  {
-       int layer, agent;
-       int id = pci_dev_id(dev);
+       struct pci_dev *dev;
+       int layer, agent, id;
        const char *level = info->level;

+ if (i >= AER_MAX_MULTI_ERR_DEVICES)

+               return;
+
+       dev = info->dev[i];
+       id = pci_dev_id(dev);
+
        pci_dev_aer_stats_incr(dev, info);
        trace_aer_event(pci_name(dev), (info->status & ~info->mask),
                        info->severity, info->tlp_header_valid, &info->tlp);
@@ -1193,19 +1199,26 @@ EXPORT_SYMBOL_GPL(aer_recover_queue);

/**

   * aer_get_device_error_info - read error status from dev and store it to info
- * @dev: pointer to the device expected to have an error record
   * @info: pointer to structure to store the error record
+ * @i: index into info->dev[]
   *
   * Return: 1 on success, 0 on error.
   *
   * Note that @info is reused among all error devices. Clear fields properly.
   */
-int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
+int aer_get_device_error_info(struct aer_err_info *info, int i)
  {
-       int type = pci_pcie_type(dev);
-       int aer = dev->aer_cap;
+       struct pci_dev *dev;
+       int type, aer;
        u32 aercc;

+ if (i >= AER_MAX_MULTI_ERR_DEVICES)

+               return 0;
+
+       dev = info->dev[i];
+       aer = dev->aer_cap;
+       type = pci_pcie_type(dev);
+
        /* Must reset in this function */
        info->status = 0;
        info->tlp_header_valid = 0;
@@ -1257,11 +1270,11 @@ static inline void aer_process_err_devices(struct 
aer_err_info *e_info)

/* Report all before handling them, to not lose records by reset etc. */

        for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
-               if (aer_get_device_error_info(e_info->dev[i], e_info))
-                       aer_print_error(e_info->dev[i], e_info);
+               if (aer_get_device_error_info(e_info, i))
+                       aer_print_error(e_info, i);
        }
        for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) {
-               if (aer_get_device_error_info(e_info->dev[i], e_info))
+               if (aer_get_device_error_info(e_info, i))
                        handle_error_source(e_info->dev[i], e_info);
        }
  }
diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c
index 7ae1590ea1da..fc18349614d7 100644
--- a/drivers/pci/pcie/dpc.c
+++ b/drivers/pci/pcie/dpc.c
@@ -253,6 +253,10 @@ static int dpc_get_aer_uncorrect_severity(struct pci_dev 
*dev,
                info->severity = AER_NONFATAL;

info->level = KERN_ERR;

+
+       info->dev[0] = dev;
+       info->error_dev_num = 1;
+
        return 1;
  }

@@ -270,8 +274,8 @@ void dpc_process_error(struct pci_dev *pdev)

                pci_warn(pdev, "containment event, status:%#06x: unmasked 
uncorrectable error detected\n",
                         status);
                if (dpc_get_aer_uncorrect_severity(pdev, &info) &&
-                   aer_get_device_error_info(pdev, &info)) {
-                       aer_print_error(pdev, &info);
+                   aer_get_device_error_info(&info, 0)) {
+                       aer_print_error(&info, 0);
                        pci_aer_clear_nonfatal_status(pdev);
                        pci_aer_clear_fatal_status(pdev);
                }

--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer