[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [RFC PATCH 00/30] Code tagging framework and applications



On Thu, Sep 01, 2022 at 10:05:03AM +0200, David Hildenbrand wrote:
> On 31.08.22 21:01, Kent Overstreet wrote:
> > On Wed, Aug 31, 2022 at 12:47:32PM +0200, Michal Hocko wrote:
> >> On Wed 31-08-22 11:19:48, Mel Gorman wrote:
> >>> Whatever asking for an explanation as to why equivalent functionality
> >>> cannot not be created from ftrace/kprobe/eBPF/whatever is reasonable.
> >>
> >> Fully agreed and this is especially true for a change this size
> >> 77 files changed, 3406 insertions(+), 703 deletions(-)
> > 
> > In the case of memory allocation accounting, you flat cannot do this with 
> > ftrace
> > - you could maybe do a janky version that isn't fully accurate, much slower,
> > more complicated for the developer to understand and debug and more 
> > complicated
> > for the end user.
> > 
> > But please, I invite anyone who's actually been doing this with ftrace to
> > demonstrate otherwise.
> > 
> > Ftrace just isn't the right tool for the job here - we're talking about 
> > adding
> > per callsite accounting to some of the fastest fast paths in the kernel.
> > 
> > And the size of the changes for memory allocation accounting are much more
> > reasonable:
> >  33 files changed, 623 insertions(+), 99 deletions(-)
> > 
> > The code tagging library should exist anyways, it's been open coded half a 
> > dozen
> > times in the kernel already.
> 
> Hi Kent,
> 
> independent of the other discussions, if it's open coded already, does
> it make sense to factor that already-open-coded part out independently
> of the remainder of the full series here?

It's discussed in the cover letter, that is exactly how the patch series is
structured.
 
> [I didn't immediately spot if this series also attempts already to
> replace that open-coded part]

Uh huh.

Honestly, some days it feels like lkml is just as bad as slashdot, with people
wanting to get in their two cents without actually reading...



 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.