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Date:   Mon, 5 Sep 2022 09:33:14 +0200
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Subject: Re: [PATCH v4 1/4] mm/slub: enable debugging memory wasting of
 kmalloc
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To:     Feng Tang <feng.tang@intel.com>
Cc:     Hyeonggon Yoo <42.hyeyoo@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Dmitry Vyukov <dvyukov@google.com>,
        "Hansen, Dave" <dave.hansen@intel.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        John Garry <john.garry@huawei.com>,
        Kefeng Wang <wangkefeng.wang@huawei.com>
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From:   Vlastimil Babka <vbabka@suse.cz>
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On 9/5/22 09:06, Feng Tang wrote:
> On Mon, Sep 05, 2022 at 02:29:51PM +0800, Vlastimil Babka wrote:
>> 
>> How about get_partial() instantiates an on-stack structure that contains
>> gfpflags, ret_slab, orig_size and passes pointer to that to all the nested
>> functions.
>> 
>> Would be similar to "struct alloc_context" in page allocation.
>> Something like "struct partial_context pc"?
> 
> Yep! This would make the parameters passing much tidier. Will try
> this way. 
> 
> More aggressively is to also embed the 'kmem_cache' parameter into
> it, but this may make the code look ambiguous.

That one is used a lot everywhere, so it would be tedious to dereference it
from a struct, and also might be a bit better code if it's in a register.

> Thanks,
> Feng
> 
>