Re: [RFC PATCH 0/6] mm/damon: hardware-sampled access reports

[SeongJae Park <sj@kernel.org>]

Hello Zeng,

On Tue, 23 Jun 2026 22:08:03 +0800 Zeng Heng <zengheng4@huawei.com> wrote:

> Hi Ravi,
> 
> On 2026/5/30 0:56, Ravi Jonnalagadda wrote:
> > This series introduces a vendor and PMU-agnostic substrate inside DAMON
> > that consumes hardware-sampled access reports through the standard
> > perf-event interface.  Userspace selects the PMU through sysfs (raw
> > type/config knobs), driving either Intel PEBS L3-miss sampling or AMD
> > IBS Op sampling.
> > 
> 
> [...]
> 
> > 
> > Ravi Jonnalagadda (6):
> >    mm/damon: add struct damon_perf_event{,_attr} and per-ctx perf_events
> >      list
> >    mm/damon/sysfs-sample: expose perf_events configuration via sysfs
> >    mm/damon/sysfs: install perf_events on apply
> >    mm/damon/core: per-CPU SPSC ring drain and damon_perf_event lifecycle
> >    mm/damon/vaddr: implement perf-event access check
> >    mm/damon: add damos_node_eligible_mem_bp tracepoint
> > 
> >   include/linux/damon.h        |  80 +++++
> >   include/trace/events/damon.h |  49 +++
> >   mm/damon/core.c              | 403 ++++++++++++++++++++----
> >   mm/damon/ops-common.h        |  39 +++
> >   mm/damon/sysfs-common.h      |   6 +
> >   mm/damon/sysfs-sample.c      | 579 +++++++++++++++++++++++++++++++++++
> >   mm/damon/sysfs.c             |   3 +
> >   mm/damon/vaddr.c             | 267 ++++++++++++++++
> >   8 files changed, 1370 insertions(+), 56 deletions(-)
> > 
> > 
> > base-commit: 4c8ad15abf15eb480d3ad85f902001e35465ef18
> 
> I wasn't able to apply this patch series to the linux (and linux-next)
> mainline branch, and also had trouble identifying the source of the base
> commit.
> 
> Would you mind sharing where this baseline is from?

TLDR: I pushed [1] a tree having this series applied on top of the baseline to
GitHub.  Please feel free to use it.

I think the baseline was a commit on damon/next tree [2].  Because damon/next
is continuously rebased, we cannot get the commit in a simple way.  Fortunately
the commit is still available on my local tree.  So I applied this patch series
on top of the commit and pushed [1] to a branch of DAMON kernel tree at GitHub.

Note that the branch is not guaranteed to exist there for long term.  But
hopefully this series will be merged into the mainline before that.

[1] https://github.com/damonitor/linux/tree/ravi_hw_sampled_access_reports_rfc_v1
[2] https://origin.kernel.org/doc/html/latest/mm/damon/maintainer-profile.html#scm-trees


Thanks,
SJ

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