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charset=us-ascii Content-Disposition: inline In-Reply-To: <20200228095819.10750-2-david@redhat.com> User-Agent: NeoMutt/20170113 (1.7.2) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Feb 28, 2020 at 10:58:18AM +0100, David Hildenbrand wrote: >In commit 52fb87c81f11 ("mm/memory_hotplug: cleanup __remove_pages()"), >we cleaned up __remove_pages(), and introduced a shorter variant to >calculate the number of pages to the next section boundary. > >Turns out we can make this calculation easier to read. We always want to >have the number of pages (> 0) to the next section boundary, starting from >the current pfn. > >We'll clean up __remove_pages() in a follow-up patch and directly make >use of this computation. > >Suggested-by: Segher Boessenkool >Cc: Andrew Morton >Cc: Oscar Salvador >Cc: Michal Hocko >Cc: Baoquan He >Cc: Dan Williams >Cc: Wei Yang >Signed-off-by: David Hildenbrand Reviewed-by: Wei Yang >--- > mm/memory_hotplug.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > >diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >index 4a9b3f6c6b37..8fe7e32dad48 100644 >--- a/mm/memory_hotplug.c >+++ b/mm/memory_hotplug.c >@@ -534,7 +534,8 @@ void __remove_pages(unsigned long pfn, unsigned long nr_pages, > for (; pfn < end_pfn; pfn += cur_nr_pages) { > cond_resched(); > /* Select all remaining pages up to the next section boundary */ >- cur_nr_pages = min(end_pfn - pfn, -(pfn | PAGE_SECTION_MASK)); >+ cur_nr_pages = min(end_pfn - pfn, >+ SECTION_ALIGN_UP(pfn + 1) - pfn); > __remove_section(pfn, cur_nr_pages, map_offset, altmap); > map_offset = 0; > } >-- >2.24.1 -- Wei Yang Help you, Help me