Re: [PATCH v3 2/3] aerdrv: Enhanced AER logging

[Borislav Petkov <bp@alien8.de>]

On Fri, Nov 30, 2012 at 02:33:37PM -0700, Lance Ortiz wrote:
> This patch will provide a more reliable and easy way for user-space
> applications to have access to AER logs rather than reading them from the
> message buffer. It also provides a way to notify user-space when an AER
> event occurs.
> 
> The aer driver is updated to generate a trace event of function 'aer_event'
> when an AER occurs.

... when a PCIe error is reported over the AER interface.

> The trace event was added to both the interrupt
> based aer path and the firmware first path
> 
> v1-v2 fix compile errors in ifdefs.
> v2-v3 Update to new location of trace header. Update print to remove
> warning.
> 
> Signed-off-by: Lance Ortiz <lance.ortiz@hp.com>
> ---
> 
>  drivers/acpi/apei/cper.c               |   17 +++++++++++++++--
>  drivers/pci/pcie/aer/aerdrv_errprint.c |   10 +++++++++-
>  include/linux/aer.h                    |    2 +-
>  3 files changed, 25 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/acpi/apei/cper.c b/drivers/acpi/apei/cper.c
> index e6defd8..e9d6062 100644
> --- a/drivers/acpi/apei/cper.c
> +++ b/drivers/acpi/apei/cper.c
> @@ -29,6 +29,7 @@
>  #include <linux/time.h>
>  #include <linux/cper.h>
>  #include <linux/acpi.h>
> +#include <linux/pci.h>
>  #include <linux/aer.h>
>  
>  /*
> @@ -249,6 +250,10 @@ static const char *cper_pcie_port_type_strs[] = {
>  static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie,
>  			    const struct acpi_hest_generic_data *gdata)
>  {
> +#ifdef CONFIG_ACPI_APEI_PCIEAER
> +	struct pci_dev *dev;
> +#endif
> +
>  	if (pcie->validation_bits & CPER_PCIE_VALID_PORT_TYPE)
>  		printk("%s""port_type: %d, %s\n", pfx, pcie->port_type,
>  		       pcie->port_type < ARRAY_SIZE(cper_pcie_port_type_strs) ?
> @@ -281,9 +286,17 @@ static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie,
>  	"%s""bridge: secondary_status: 0x%04x, control: 0x%04x\n",
>  	pfx, pcie->bridge.secondary_status, pcie->bridge.control);
>  #ifdef CONFIG_ACPI_APEI_PCIEAER
> -	if (pcie->validation_bits & CPER_PCIE_VALID_AER_INFO) {
> +	dev = pci_get_domain_bus_and_slot(pcie->device_id.segment,
> +			pcie->device_id.bus, pcie->device_id.function);
> +	if (!dev)
> +		pr_info("PCI AER Cannot get PCI device %04x:%02x:%02x.%d\n",
> +			pcie->device_id.segment, pcie->device_id.bus,
> +			pcie->device_id.slot, pcie->device_id.function);
> +
> +	if (pcie->validation_bits & CPER_PCIE_VALID_AER_INFO && dev) {

You don't need to test dev here because you've tested for !dev in the
line above...

>  		struct aer_capability_regs *aer_regs = (void *)pcie->aer_info;
> -		cper_print_aer(pfx, gdata->error_severity, aer_regs);
> +		cper_print_aer(dev, gdata->error_severity, aer_regs);
> +		pci_dev_put(dev);

... and thus this pci_dev_put() has to be unconditional, i.e. after the
if test.

which means that you can simplify the last 4 lines like this:

	if (pcie->validation_bits & CPER_PCIE_VALID_AER_INFO)
		cper_print_aer(dev, gdata->error_severity,
			       (struct aer_capability_regs *)pcie->aer_info);

	pci_dev_put(dev);

...

Thanks.

-- 
Regards/Gruss,
    Boris.