[PATCH v8 04/23] slab: add sheaf support for batching kfree_rcu() operations

[Jon Hunter]

On 27/11/2025 13:18, Vlastimil Babka wrote:
> On 11/27/25 12:38, Jon Hunter wrote:
>>
>>
>> On 31/10/2025 21:32, Daniel Gomez wrote:
>>>
>>>
>>> On 10/09/2025 10.01, Vlastimil Babka wrote:
>>>
>>> Hi Vlastimil,
>>>
>>> This patch increases kmod selftest (stress module loader) runtime by about
>>> ~50-60%, from ~200s to ~300s total execution time. My tested kernel has
>>> CONFIG_KVFREE_RCU_BATCHED enabled. Any idea or suggestions on what might be
>>> causing this, or how to address it?
>>>
>>
>> I have been looking into a regression for Linux v6.18-rc where time
>> taken to run some internal graphics tests on our Tegra234 device has
>> increased from around 35% causing the tests to timeout. Bisect is
>> pointing to this commit and I also see we have CONFIG_KVFREE_RCU_BATCHED=y.
> 
> Do the tegra tests involve (frequent) module unloads too, then? Or calling
> kmem_cache_destroy() somewhere?

In this specific case I am not running the tegra-tests but we have a 
internal testsuite of GPU related tests. I don't believe that believe 
this is unloading any modules. I can take a look next week to see if 
kmem_cache_destroy() is getting called somewhere when these tests run.

Thanks
Jon

-- 
nvpublic