From: Baoquan He <bhe@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org, akpm@linux-foundation.org,
dan.j.williams@intel.com, richardw.yang@linux.intel.com,
david@redhat.com, bhe@redhat.com
Subject: [PATCH 2/7] mm/sparse.c: Introduce a new function clear_subsection_map()
Date: Sun, 9 Feb 2020 18:48:21 +0800 [thread overview]
Message-ID: <20200209104826.3385-3-bhe@redhat.com> (raw)
In-Reply-To: <20200209104826.3385-1-bhe@redhat.com>
Wrap the codes clearing subsection map of one memory region in
section_deactivate() into clear_subsection_map().
Signed-off-by: Baoquan He <bhe@redhat.com>
---
mm/sparse.c | 44 +++++++++++++++++++++++++++++++++++++-------
1 file changed, 37 insertions(+), 7 deletions(-)
diff --git a/mm/sparse.c b/mm/sparse.c
index 9ad741ccbeb6..696f6b9f706e 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -726,14 +726,25 @@ static void free_map_bootmem(struct page *memmap)
}
#endif /* CONFIG_SPARSEMEM_VMEMMAP */
-static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
- struct vmem_altmap *altmap)
+/**
+ * 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);
- bool section_is_early = early_section(ms);
- struct page *memmap = NULL;
unsigned long *subsection_map = ms->usage
? &ms->usage->subsection_map[0] : NULL;
@@ -744,8 +755,28 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
if (WARN(!subsection_map || !bitmap_equal(tmp, map, SUBSECTIONS_PER_SECTION),
"section already deactivated (%#lx + %ld)\n",
pfn, nr_pages))
- return;
+ return -EINVAL;
+
+ bitmap_xor(subsection_map, map, subsection_map, SUBSECTIONS_PER_SECTION);
+ if (bitmap_empty(subsection_map, SUBSECTIONS_PER_SECTION))
+ return 0;
+
+ return 1;
+}
+
+static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
+ struct vmem_altmap *altmap)
+{
+ struct mem_section *ms = __pfn_to_section(pfn);
+ bool section_is_early = early_section(ms);
+ struct page *memmap = NULL;
+ int rc;
+
+
+ rc = clear_subsection_map(pfn, nr_pages);
+ if(IS_ERR_VALUE((unsigned long)rc))
+ return;
/*
* There are 3 cases to handle across two configurations
* (SPARSEMEM_VMEMMAP={y,n}):
@@ -763,8 +794,7 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages,
*
* For 2/ and 3/ the SPARSEMEM_VMEMMAP={y,n} cases are unified
*/
- bitmap_xor(subsection_map, map, subsection_map, SUBSECTIONS_PER_SECTION);
- if (bitmap_empty(subsection_map, SUBSECTIONS_PER_SECTION)) {
+ if (!rc) {
unsigned long section_nr = pfn_to_section_nr(pfn);
/*
--
2.17.2
next prev parent reply other threads:[~2020-02-09 10:48 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-09 10:48 [PATCH 0/7] mm/hotplug: Only use subsection in VMEMMAP case and fix hot add/remove failure in SPARSEMEM|!VMEMMAP case Baoquan He
2020-02-09 10:48 ` [PATCH 1/7] mm/sparse.c: Introduce new function fill_subsection_map() Baoquan He
2020-02-09 23:05 ` Wei Yang
2020-02-09 23:11 ` Wei Yang
2020-02-10 3:25 ` Baoquan He
2020-02-10 9:49 ` David Hildenbrand
2020-02-11 12:46 ` Baoquan He
2020-02-11 14:44 ` David Hildenbrand
2020-02-12 11:21 ` Baoquan He
2020-02-09 10:48 ` Baoquan He [this message]
2020-02-09 23:07 ` [PATCH 2/7] mm/sparse.c: Introduce a new function clear_subsection_map() Wei Yang
2020-02-10 3:36 ` Baoquan He
2020-02-10 6:02 ` Wei Yang
2020-02-09 10:48 ` [PATCH 3/7] mm/sparse.c: only use subsection map in VMEMMAP case Baoquan He
2020-02-09 23:23 ` Wei Yang
2020-02-11 14:43 ` David Hildenbrand
2020-02-12 11:26 ` Baoquan He
2020-02-11 20:14 ` Dan Williams
2020-02-12 9:39 ` David Hildenbrand
2020-02-12 11:20 ` Baoquan He
2020-02-12 15:48 ` Dan Williams
2020-02-09 10:48 ` [PATCH 4/7] mm/sparse.c: Use __get_free_pages() instead in populate_section_memmap() Baoquan He
2020-02-09 23:39 ` Wei Yang
2020-02-09 10:48 ` [PATCH 5/7] mm/sparse.c: update code comment about section activate/deactivate Baoquan He
2020-02-09 10:48 ` [PATCH 6/7] mm/sparsemem: pfn_to_page is not valid yet on SPARSEMEM Baoquan He
2020-02-10 3:45 ` Baoquan He
2020-02-09 10:48 ` [PATCH 7/7] mm/hotplug: fix hot remove failure in SPARSEMEM|!VMEMMAP case Baoquan He
2020-02-09 23:52 ` Wei Yang
2020-02-10 3:41 ` Baoquan He
2020-02-10 6:08 ` Wei Yang
2020-02-10 7:54 ` Baoquan He
2020-02-10 23:05 ` Wei Yang
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