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From:   Z qiang <qiang.zhang1211@gmail.com>
Date:   Tue, 10 Oct 2023 10:53:31 +0800
Message-ID: <CALm+0cUU3nvzk-A6+4zF5fCrkQ_dDY6GE81L97qU-xyCHCsaww@mail.gmail.com>
Subject: Re: [PATCH] workqueue: Use the kmem_cache_free() instead of kfree()
 to release pwq
To:     Tejun Heo <tj@kernel.org>
Cc:     jiangshanlai@gmail.com, linux-kernel@vger.kernel.org
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>
> On Sat, Oct 07, 2023 at 07:35:41PM +0800, Zqiang wrote:
> > The pwq objects is allocated by kmem_cache_alloc(), this commit therefore
> > use kmem_cache_free() instead of kfree() to release pwq objects and also
> > make use the correct tracepoint("trace_kmem_cache_free") to trace the
> > release of pwq.
>
> This isn't wrong. kfree() can be used for memory allocated with
> kmem_cache_alloc().
>

Yes, that's not wrong.  but pwq is allocated by kmem_cache_alloc(),
usually should use kmem_cache_free() to release, correspondingly, we can
use 'trace_kmem_cache_alloc/trace_kmem_cache_free' to track, not using
'trace_kmem_cache_alloc/trace_kfree'.
And in rcu_free_pwq(), we use kmem_cache_free() to free pwq.

Thanks
Zqiang


>
> Thanks.
>
> --
> tejun