Re: [PATCH v20 0/6] Hierarchical Percpu Counters for RSS

On 2026-07-23 13:53, Mathieu Desnoyers wrote:
> On 2026-07-07 09:15, Mathieu Desnoyers wrote:
>> Hi Andrew,
>>
>> Here is the hierarchical percpu counters series rebased on top of
>> v7.2-rc2. It includes small bootup fixes which were needed to fix
>> bootup sequence on specific architectures, and a rename of the
>> test config option to include "KUNIT_".
>>
>> This aims at replacing the prior version of the series you had
>> in mm.
>>
>> As a reminder, the goal here is to provide more precise RSS counters
>> through /proc.
> 
> Hello,
> 
> Just a gentle ping for feedback whenever it's convenient.

Hi Andrew,

Can you pick this up after the upcoming merge window ?

That's of course assuming this is solving an issue which is
still relevant.

If there is no interest in solving this issue anymore, kindly
let me know and I'll drop this series.

Thanks,

Mathieu

> 
> Thanks,
> 
> Mathieu
> 
>>
>> Thanks,
>>
>> Mathieu
>>
>> Mathieu Desnoyers (6):
>>    lib: introduce hierarchical per-cpu counters
>>    lib: test hierarchical per-cpu counters
>>    mm: improve RSS counter approximation accuracy for proc interfaces
>>    mm: reorder mm_struct flexible array to place mm_cpumask first
>>    init: move percpu_counter_tree_subsystem_init() earlier in boot
>>    lib: inline percpu_counter_tree_items_size with boot-safety sentinel
>>
>> Cc: "Paul E. McKenney" <[email protected]>
>> Cc: Steven Rostedt <[email protected]>
>> Cc: Masami Hiramatsu <[email protected]>
>> Cc: Mathieu Desnoyers <[email protected]>
>> Cc: Dennis Zhou <[email protected]>
>> Cc: Tejun Heo <[email protected]>
>> Cc: Christoph Lameter <[email protected]>
>> Cc: Martin Liu <[email protected]>
>> Cc: David Rientjes <[email protected]>
>> Cc: [email protected]
>> Cc: Shakeel Butt <[email protected]>
>> Cc: SeongJae Park <[email protected]>
>> Cc: Michal Hocko <[email protected]>
>> Cc: Johannes Weiner <[email protected]>
>> Cc: Sweet Tea Dorminy <[email protected]>
>> Cc: Lorenzo Stoakes <[email protected]>
>> Cc: "Liam R . Howlett" <[email protected]>
>> Cc: Mike Rapoport <[email protected]>
>> Cc: Suren Baghdasaryan <[email protected]>
>> Cc: Vlastimil Babka <[email protected]>
>> Cc: Christian Brauner <[email protected]>
>> Cc: Wei Yang <[email protected]>
>> Cc: David Hildenbrand <[email protected]>
>> Cc: Miaohe Lin <[email protected]>
>> Cc: Al Viro <[email protected]>
>> Cc: Yu Zhao <[email protected]>
>> Cc: Roman Gushchin <[email protected]>
>> Cc: Mateusz Guzik <[email protected]>
>> Cc: Matthew Wilcox <[email protected]>
>> Cc: Baolin Wang <[email protected]>
>> Cc: Aboorva Devarajan <[email protected]>
>> Cc: David Carlier <[email protected]>
>> Cc: Josh Law <[email protected]>
>> Cc: Andrew Morton <[email protected]>
>>
>>   .../core-api/percpu-counter-tree.rst          |  75 ++
>>   include/linux/mm.h                            |  20 +-
>>   include/linux/mm_types.h                      |  65 +-
>>   include/linux/percpu_counter_tree.h           | 387 ++++++++++
>>   include/trace/events/kmem.h                   |   2 +-
>>   init/main.c                                   |   2 +
>>   kernel/fork.c                                 |  24 +-
>>   lib/Kconfig                                   |  12 +
>>   lib/Makefile                                  |   1 +
>>   lib/percpu_counter_tree.c                     | 694 ++++++++++++++++++
>>   lib/tests/Makefile                            |   2 +
>>   lib/tests/percpu_counter_tree_kunit.c         | 399 ++++++++++
>>   12 files changed, 1651 insertions(+), 32 deletions(-)
>>   create mode 100644 Documentation/core-api/percpu-counter-tree.rst
>>   create mode 100644 include/linux/percpu_counter_tree.h
>>   create mode 100644 lib/percpu_counter_tree.c
>>   create mode 100644 lib/tests/percpu_counter_tree_kunit.c
>>
> 
> 


-- 
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com