Re: [PATCH -v4 0/2] mm: vmscan: fix node reclaim ignoring swappiness parameter

Ridong Chen <[email protected]> Fri, 24 Jul 2026 09:11:18 +0800
Newsgroups org.kernel.vger.cgroups,org.kernel.vger.linux-kernel,org.kvack.linux-mm
Message-ID <[email protected]>

On 7/24/2026 8:34 AM, Andrew Morton wrote:
> On Thu, 23 Jul 2026 11:24:32 +0800 Ridong <[email protected]> wrote:
> 
>> From: Ridong Chen <[email protected]>
>>
>> The per-node proactive reclaim interface
>> (/sys/devices/system/node/nodeX/reclaim) accepts a swappiness parameter,
>> but it is silently ignored when CONFIG_MEMCG is disabled. The root cause
>> is that sc_swappiness() has separate implementations for CONFIG_MEMCG and
>> !CONFIG_MEMCG, and the latter never checks proactive_swappiness.
>>
>> Patch 1 moves mem_cgroup_swappiness() and vm_swappiness out of the public
>> include/linux/swap.h into the mm-private mm/swap.h, and makes the helper
>> handle both CONFIG_MEMCG and !CONFIG_MEMCG in a single inline function.
>> This is a prerequisite for unifying sc_swappiness().
>>
>> Patch 2 consolidates sc_swappiness() into a single definition that works
>> regardless of CONFIG_MEMCG, fixing the node reclaim swappiness bug.
> 
> Thanks, I updated mm.git to this version.
> 
Thanks.

-- 
Best regards
Ridong