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Groups > linux.kernel > #1545640
| From | Michal Hocko <mhocko@kernel.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH V2 1/2] mm/memblock.c: trivial code refine in memblock_is_region_memory() |
| Date | 2016-12-21 08:50 +0100 |
| Message-ID | <sQJOW-uc-11@gated-at.bofh.it> (permalink) |
| References | <sPKWJ-C5-3@gated-at.bofh.it> <sPKWJ-C5-19@gated-at.bofh.it> <sQ7Tk-1bC-23@gated-at.bofh.it> <sQvCh-7WT-7@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Tue 20-12-16 16:35:40, Wei Yang wrote:
> On Mon, Dec 19, 2016 at 04:15:14PM +0100, Michal Hocko wrote:
> >On Sun 18-12-16 14:47:49, Wei Yang wrote:
> >> The base address is already guaranteed to be in the region by
> >> memblock_search().
> >
>
> Hi, Michal
>
> Nice to receive your comment.
>
> >First of all the way how the check is removed is the worst possible...
> >Apart from that it is really not clear to me why checking the base
> >is not needed. You are mentioning memblock_search but what about other
> >callers? adjust_range_page_size_mask e.g...
> >
>
> Hmm... the memblock_search() is called by memblock_is_region_memory(). Maybe I
> paste the whole function here would clarify the change.
>
> int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
> {
> int idx = memblock_search(&memblock.memory, base);
> phys_addr_t end = base + memblock_cap_size(base, &size);
>
> if (idx == -1)
> return 0;
> return memblock.memory.regions[idx].base <= base &&
> (memblock.memory.regions[idx].base +
> memblock.memory.regions[idx].size) >= end;
> }
Ohh, my bad. I thought that memblock_search is calling
memblock_is_region_memory. I didn't notice this is other way around.
Then I agree that the check for the base is not needed and can be
removed.
--
Michal Hocko
SUSE Labs
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[PATCH V2 0/2] mm/memblock.c: fix potential bug and code refine Wei Yang <richard.weiyang@gmail.com> - 2016-12-18 15:50 +0100
[PATCH V2 2/2] mm/memblock.c: check return value of memblock_reserve() in memblock_virt_alloc_internal() Wei Yang <richard.weiyang@gmail.com> - 2016-12-18 15:50 +0100
Re: [PATCH V2 2/2] mm/memblock.c: check return value of memblock_reserve() in memblock_virt_alloc_internal() Michal Hocko <mhocko@kernel.org> - 2016-12-19 16:30 +0100
Re: [PATCH V2 2/2] mm/memblock.c: check return value of memblock_reserve() in memblock_virt_alloc_internal() Wei Yang <richard.weiyang@gmail.com> - 2016-12-20 17:50 +0100
Re: [PATCH V2 2/2] mm/memblock.c: check return value of memblock_reserve() in memblock_virt_alloc_internal() Michal Hocko <mhocko@kernel.org> - 2016-12-21 09:00 +0100
Re: [PATCH V2 2/2] mm/memblock.c: check return value of memblock_reserve() in memblock_virt_alloc_internal() Wei Yang <richard.weiyang@gmail.com> - 2016-12-21 14:20 +0100
Re: [PATCH V2 2/2] mm/memblock.c: check return value of memblock_reserve() in memblock_virt_alloc_internal() Michal Hocko <mhocko@kernel.org> - 2016-12-21 14:30 +0100
Re: [PATCH V2 2/2] mm/memblock.c: check return value of memblock_reserve() in memblock_virt_alloc_internal() Wei Yang <richard.weiyang@gmail.com> - 2016-12-21 15:50 +0100
Re: [PATCH V2 2/2] mm/memblock.c: check return value of memblock_reserve() in memblock_virt_alloc_internal() Michal Hocko <mhocko@kernel.org> - 2016-12-21 16:00 +0100
[PATCH V2 1/2] mm/memblock.c: trivial code refine in memblock_is_region_memory() Wei Yang <richard.weiyang@gmail.com> - 2016-12-18 15:50 +0100
Re: [PATCH V2 1/2] mm/memblock.c: trivial code refine in memblock_is_region_memory() Michal Hocko <mhocko@kernel.org> - 2016-12-19 16:20 +0100
Re: [PATCH V2 1/2] mm/memblock.c: trivial code refine in memblock_is_region_memory() Wei Yang <richard.weiyang@gmail.com> - 2016-12-20 17:40 +0100
Re: [PATCH V2 1/2] mm/memblock.c: trivial code refine in memblock_is_region_memory() Michal Hocko <mhocko@kernel.org> - 2016-12-21 08:50 +0100
Re: [PATCH V2 1/2] mm/memblock.c: trivial code refine in memblock_is_region_memory() Michal Hocko <mhocko@kernel.org> - 2016-12-21 13:50 +0100
Re: [PATCH V2 1/2] mm/memblock.c: trivial code refine in memblock_is_region_memory() Wei Yang <richard.weiyang@gmail.com> - 2016-12-21 14:20 +0100
Re: [PATCH V2 1/2] mm/memblock.c: trivial code refine in memblock_is_region_memory() Wei Yang <richard.weiyang@gmail.com> - 2016-12-21 13:50 +0100
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