Messages in this thread | | | From | Muchun Song <> | Date | Fri, 11 Dec 2020 00:19:50 +0800 | Subject | Re: [External] Re: [PATCH v8 12/12] mm/hugetlb: Optimize the code with the help of the compiler |
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On Thu, Dec 10, 2020 at 9:29 PM Muchun Song <songmuchun@bytedance.com> wrote: > > On Thu, Dec 10, 2020 at 9:16 PM Oscar Salvador <osalvador@suse.de> wrote: > > > > On Thu, Dec 10, 2020 at 08:14:18PM +0800, Muchun Song wrote: > > > Yeah, you are right. But if we do this check can make the code simple. > > > > > > For example, here is a code snippet. > > > > > > void func(void) > > > { > > > if (free_vmemmap_pages_per_hpage()) > > > return; > > > /* Do something */ > > > } > > > > > > With this patch, the func will be optimized to null when is_power_of_2 > > > returns false. > > > > > > void func(void) > > > { > > > } > > > > > > Without this patch, the compiler cannot do this optimization. > > > > Ok, I misread the changelog. > > > > So, then is_hugetlb_free_vmemmap_enabled, free_huge_page_vmemmap, > > free_vmemmap_pages_per_hpage and hugetlb_vmemmap_init are optimized > > out, right? > > Yes, that's right. I have disassembled to make sure of this. Thanks.
Hi Oscar,
Because this is an optimization for code, I leave it in this separate patch. Do you still suggest squash this with patch#10? Thanks.
> > > > > -- > > Oscar Salvador > > SUSE L3 > > > > -- > Yours, > Muchun
-- Yours, Muchun
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