On 02/10/20 at 07:05am, Wei Yang wrote: > >-static struct page * __meminit section_activate(int nid, unsigned long pfn, > >- unsigned long nr_pages, struct vmem_altmap *altmap) > >+/** > >+ * fill_subsection_map - fill subsection map of a memory region > >+ * @pfn - start pfn of the memory range > >+ * @nr_pages - number of pfns to add in the region > >+ * > >+ * This clears the related subsection map inside one section, and only > > s/clears/fills/ ? Good catch, thanks for your careful review. I will wait a while to see if there's any input from other reviewers, then update this post accordingly together. > > >+ * intended for hotplug. > >+ * > >+ * Return: > >+ * * 0 - On success. > >+ * * -EINVAL - Invalid memory region. > >+ * * -EEXIST - Subsection map has been set. > >+ */ > >+static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages) > > { > >- DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 }; > > struct mem_section *ms = __pfn_to_section(pfn); > >- struct mem_section_usage *usage = NULL; > >+ DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 }; > > unsigned long *subsection_map; > >- struct page *memmap; > > int rc = 0; > > > > subsection_mask_set(map, pfn, nr_pages); > > > >- if (!ms->usage) { > >- usage = kzalloc(mem_section_usage_size(), GFP_KERNEL); > >- if (!usage) > >- return ERR_PTR(-ENOMEM); > >- ms->usage = usage; > >- } > > subsection_map = &ms->usage->subsection_map[0]; > > > > if (bitmap_empty(map, SUBSECTIONS_PER_SECTION)) > >@@ -816,6 +820,25 @@ static struct page * __meminit section_activate(int nid, unsigned long pfn, > > bitmap_or(subsection_map, map, subsection_map, > > SUBSECTIONS_PER_SECTION); > > > >+ return rc; > >+} > >+ > >+static struct page * __meminit section_activate(int nid, unsigned long pfn, > >+ unsigned long nr_pages, struct vmem_altmap *altmap) > >+{ > >+ struct mem_section *ms = __pfn_to_section(pfn); > >+ struct mem_section_usage *usage = NULL; > >+ struct page *memmap; > >+ int rc = 0; > >+ > >+ if (!ms->usage) { > >+ usage = kzalloc(mem_section_usage_size(), GFP_KERNEL); > >+ if (!usage) > >+ return ERR_PTR(-ENOMEM); > >+ ms->usage = usage; > >+ } > >+ > >+ rc = fill_subsection_map(pfn, nr_pages); > > if (rc) { > > if (usage) > > ms->usage = NULL; > >-- > >2.17.2 > > -- > Wei Yang > Help you, Help me >