On Fri, Jan 31, 2025 at 6:33 AM Jonathan Cameron
<Jonathan.Cameron@xxxxxxxxxx> wrote:
>
> On Tue, 14 Jan 2025 23:42:58 -0800
> Jon Pan-Doh <pandoh@xxxxxxxxxx> wrote:
> > +
> > +These attributes show up under all the devices that are AER capable. Provides
> > +configurable ratelimits of logs/irq per error type. Writing a nonzero value
> > +changes the number of errors (burst) allowed per 5 second window before
> > +ratelimiting. Reading gets the current ratelimits.
> > +
> > +What: /sys/bus/pci/devices/<dev>/aer/ratelimit_cor_irq
> > +Date: Jan 2025
> > +KernelVersion: 6.14.0
> > +Contact: linux-pci@xxxxxxxxxxxxxxx, pandoh@xxxxxxxxxx
> > +Description: IRQ ratelimit for correctable errors.
>
> I would add enough info that we can understand what values to write and what
> to read to each description. This doc didn't lead me to the comment below
> and it should have done...
Since there's a lot of commonality in the descriptions, I opted for
putting the bulk of info at the top of "PCIe AER ratelimits" section.
I believe I already wrote what should be written/read. Is there extra
specificity you are looking for?
How does this look?
PCIe AER ratelimits
-------------------
These attributes show up under all the devices that are AER capable.
They represent configurable ratelimits of logs per error type. Writing a
value changes the number of errors (burst) allowed per interval
(5 second window) before ratelimiting. Reading gets the current ratelimit
burst.
See Documentation/PCI/pcieaer-howto.rst for more info on ratelimits.
What: /sys/bus/pci/devices/<dev>/aer/ratelimit_in_5secs_cor_log
Date: March 2025
KernelVersion: 6.15.0
Contact: linux-pci@xxxxxxxxxxxxxxx, pandoh@xxxxxxxxxx
Description: Ratelimit burst for correctable error logs.
> > +#define aer_ratelimit_attr(name, ratelimit) \
> > + static ssize_t \
> > + name##_show(struct device *dev, struct device_attribute *attr, \
> > + char *buf) \
> > +{ \
> > + struct pci_dev *pdev = to_pci_dev(dev); \
> > + return sysfs_emit(buf, "%u errors every %u seconds\n", \
> > + pdev->aer_info->ratelimit.burst, \
> > + pdev->aer_info->ratelimit.interval / HZ); \
>
> Usual rule of thumb is you need a very strong reason to read something
> different from what was written to a sysfs file.
Ack. Will make read/write symmetric in v3.
> I think your interval is fixed? If so name the files so that is apparent
> and just have a count returned here. Or if you want to future proof
> add a read only ratelimit_period_secs file that prints 5
>
> ratelimit_in_5secs_uncor_log etc.
Yes, the interval is fixed. Will update sysfs entry names to be more
specific in v3.
Thanks,
Jon
