On 06/09/23(Wed) 23:13, Alexander Bluhm wrote: > On Wed, Sep 06, 2023 at 12:23:33PM -0500, Scott Cheloha wrote: > > On Wed, Sep 06, 2023 at 01:04:19PM +0100, Martin Pieuchot wrote: > > > Debugging OOM is hard. UVM uses per-CPU counters and sadly > > > counters_read(9) needs to allocate memory. This is not acceptable in > > > ddb(4). As a result I cannot see the content of UVM counters in OOM > > > situations. > > > > > > Diff below introduces a *_static() variant of counters_read(9) that > > > takes a secondary buffer to avoid calling malloc(9). Is it fine? Do > > > you have a better idea? Should we make it the default or using the > > > stack might be a problem? > > > > Instead of adding a second interface I think we could get away with > > just extending counters_read(9) to take a scratch buffer as an optional > > fourth parameter: > > > > void > > counters_read(struct cpumem *cm, uint64_t *output, unsigned int n, > > uint64_t *scratch); > > > > "scratch"? "temp"? "tmp"? > > scratch is fine for me
Fine with me.
