Re: [PATCH V2 1/1] net: cdc_ncm: Reduce memory use when kernel memory low

["Bjørn Mork" <bjorn@mork.no>]

"Baxter, Jim" <jim_baxter@mentor.com> writes:

> I tested this with printk's to show when the low memory code was triggered
> and the value of ctx->tx_low_mem_val and ctx->tx_low_mem_max_cnt.
> I created a workqueue that slowly used up the atomic memory until the
> code is triggered.
>
> I could add debug prints, though I have noticed that cdc_ncm_fill_tx_frame()
> does not currently have any debug prints do you think this is because it can be
> called in an atomic context and I think debug messages if enabled could cause
> too great a delay?

Yes, I guess you're right.  Maybe count the number of failed allocations
and export it along with the other driver private counters?  Or export
the tx_curr_size as a sysfs attribute? Or both?

Just an idea...  I don't expect to see this code ever being hit on my
systems :-)



Bjørn