Re: [PATCH v2 6/7] mm/sparse.c: move subsection_map related codes together

[Wei Yang]

On Thu, Feb 20, 2020 at 12:33:15PM +0800, Baoquan He wrote:
>No functional change.
>

Those functions are introduced in your previous patches.

Is it possible to define them close to each other at the very beginning?

>Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
>---
> mm/sparse.c | 172 +++++++++++++++++++++++++---------------------------
> 1 file changed, 84 insertions(+), 88 deletions(-)
>
>diff --git a/mm/sparse.c b/mm/sparse.c
>index 14bff0b44e7c..053d6c2e5c1f 100644
>--- a/mm/sparse.c
>+++ b/mm/sparse.c
>@@ -244,10 +244,94 @@ void __init subsection_map_init(unsigned long pfn, unsigned long nr_pages)
> 		nr_pages -= pfns;
> 	}
> }
>+
>+/**
>+ * clear_subsection_map - Clear subsection map of one memory region
>+ *
>+ * @pfn - start pfn of the memory range
>+ * @nr_pages - number of pfns to add in the region
>+ *
>+ * This is only intended for hotplug, and clear the related subsection
>+ * map inside one section.
>+ *
>+ * Return:
>+ * * -EINVAL	- Section already deactived.
>+ * * 0		- Subsection map is emptied.
>+ * * 1		- Subsection map is not empty.
>+ */
>+static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages)
>+{
>+	DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
>+	DECLARE_BITMAP(tmp, SUBSECTIONS_PER_SECTION) = { 0 };
>+	struct mem_section *ms = __pfn_to_section(pfn);
>+	unsigned long *subsection_map = ms->usage
>+		? &ms->usage->subsection_map[0] : NULL;
>+
>+	subsection_mask_set(map, pfn, nr_pages);
>+	if (subsection_map)
>+		bitmap_and(tmp, map, subsection_map, SUBSECTIONS_PER_SECTION);
>+
>+	if (WARN(!subsection_map || !bitmap_equal(tmp, map, SUBSECTIONS_PER_SECTION),
>+				"section already deactivated (%#lx + %ld)\n",
>+				pfn, nr_pages))
>+		return -EINVAL;
>+
>+	bitmap_xor(subsection_map, map, subsection_map, SUBSECTIONS_PER_SECTION);
>+
>+	if (bitmap_empty(subsection_map, SUBSECTIONS_PER_SECTION))
>+		return 0;
>+
>+	return 1;
>+}
>+
>+/**
>+ * 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 fills the related subsection map inside one section, and only
>+ * 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)
>+{
>+	struct mem_section *ms = __pfn_to_section(pfn);
>+	DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
>+	unsigned long *subsection_map;
>+	int rc = 0;
>+
>+	subsection_mask_set(map, pfn, nr_pages);
>+
>+	subsection_map = &ms->usage->subsection_map[0];
>+
>+	if (bitmap_empty(map, SUBSECTIONS_PER_SECTION))
>+		rc = -EINVAL;
>+	else if (bitmap_intersects(map, subsection_map, SUBSECTIONS_PER_SECTION))
>+		rc = -EEXIST;
>+	else
>+		bitmap_or(subsection_map, map, subsection_map,
>+				SUBSECTIONS_PER_SECTION);
>+
>+	return rc;
>+}
> #else
> void __init subsection_map_init(unsigned long pfn, unsigned long nr_pages)
> {
> }
>+
>+static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages)
>+{
>+	return 0;
>+}
>+
>+static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages)
>+{
>+	return 0;
>+}
> #endif
> 
> /* Record a memory area against a node. */
>@@ -732,52 +816,6 @@ static void free_map_bootmem(struct page *memmap)
> }
> #endif /* CONFIG_SPARSEMEM_VMEMMAP */
> 
>-#ifdef CONFIG_SPARSEMEM_VMEMMAP
>-/**
>- * clear_subsection_map - Clear subsection map of one memory region
>- *
>- * @pfn - start pfn of the memory range
>- * @nr_pages - number of pfns to add in the region
>- *
>- * This is only intended for hotplug, and clear the related subsection
>- * map inside one section.
>- *
>- * Return:
>- * * -EINVAL	- Section already deactived.
>- * * 0		- Subsection map is emptied.
>- * * 1		- Subsection map is not empty.
>- */
>-static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages)
>-{
>-	DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
>-	DECLARE_BITMAP(tmp, SUBSECTIONS_PER_SECTION) = { 0 };
>-	struct mem_section *ms = __pfn_to_section(pfn);
>-	unsigned long *subsection_map = ms->usage
>-		? &ms->usage->subsection_map[0] : NULL;
>-
>-	subsection_mask_set(map, pfn, nr_pages);
>-	if (subsection_map)
>-		bitmap_and(tmp, map, subsection_map, SUBSECTIONS_PER_SECTION);
>-
>-	if (WARN(!subsection_map || !bitmap_equal(tmp, map, SUBSECTIONS_PER_SECTION),
>-				"section already deactivated (%#lx + %ld)\n",
>-				pfn, nr_pages))
>-		return -EINVAL;
>-
>-	bitmap_xor(subsection_map, map, subsection_map, SUBSECTIONS_PER_SECTION);
>-
>-	if (bitmap_empty(subsection_map, SUBSECTIONS_PER_SECTION))
>-		return 0;
>-
>-	return 1;
>-}
>-#else
>-static int clear_subsection_map(unsigned long pfn, unsigned long nr_pages)
>-{
>-	return 0;
>-}
>-#endif
>-
> /*
>  * To deactivate a memory region, there are 3 cases to handle across
>  * two configurations (SPARSEMEM_VMEMMAP={y,n}):
>@@ -833,48 +871,6 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
> 		ms->section_mem_map = (unsigned long)NULL;
> }
> 
>-#ifdef CONFIG_SPARSEMEM_VMEMMAP
>-/**
>- * 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 fills the related subsection map inside one section, and only
>- * 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)
>-{
>-	struct mem_section *ms = __pfn_to_section(pfn);
>-	DECLARE_BITMAP(map, SUBSECTIONS_PER_SECTION) = { 0 };
>-	unsigned long *subsection_map;
>-	int rc = 0;
>-
>-	subsection_mask_set(map, pfn, nr_pages);
>-
>-	subsection_map = &ms->usage->subsection_map[0];
>-
>-	if (bitmap_empty(map, SUBSECTIONS_PER_SECTION))
>-		rc = -EINVAL;
>-	else if (bitmap_intersects(map, subsection_map, SUBSECTIONS_PER_SECTION))
>-		rc = -EEXIST;
>-	else
>-		bitmap_or(subsection_map, map, subsection_map,
>-				SUBSECTIONS_PER_SECTION);
>-
>-	return rc;
>-}
>-#else
>-static int fill_subsection_map(unsigned long pfn, unsigned long nr_pages)
>-{
>-	return 0;
>-}
>-#endif
>-
> static struct page * __meminit section_activate(int nid, unsigned long pfn,
> 		unsigned long nr_pages, struct vmem_altmap *altmap)
> {
>-- 
>2.17.2

-- 
Wei Yang
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