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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Feb 05, 2020 at 10:48:11PM +0800, Baoquan He wrote: >Hi Wei Yang, > >On 02/05/20 at 05:59pm, Wei Yang wrote: >> >diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >> >index f294918f7211..8dafa1ba8d9f 100644 >> >--- a/mm/memory_hotplug.c >> >+++ b/mm/memory_hotplug.c >> >@@ -393,6 +393,9 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, >> > if (pfn) { >> > zone->zone_start_pfn = pfn; >> > zone->spanned_pages = zone_end_pfn - pfn; >> >+ } else { >> >+ zone->zone_start_pfn = 0; >> >+ zone->spanned_pages = 0; >> > } >> > } else if (zone_end_pfn == end_pfn) { >> > /* >> >@@ -405,34 +408,11 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn, >> > start_pfn); >> > if (pfn) >> > zone->spanned_pages = pfn - zone_start_pfn + 1; >> >+ else { >> >+ zone->zone_start_pfn = 0; >> >+ zone->spanned_pages = 0; >> >+ } >> > } >> >> If it is me, I would like to take out these two similar logic out. > >I also like this style. >> >> For example: >> >> if () { >> } else if () { >> } else { >> goto out; >Here the last else is unnecessary, right? > I am afraid not. If the range is not the first or last, we would leave pfn not initialized. -- Wei Yang Help you, Help me _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel