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| author | Baoquan He <bhe@redhat.com> | 2020-04-06 20:07:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-04-07 10:43:40 -0700 |
| commit | 37bc15020a96035cb157be5864b958672fe02d7c (patch) | |
| tree | 3f189646ac8d1fcd92bb712c840dee078797ecb5 /mm/sparse.c | |
| parent | 5d87255cadde243763ca22b35e01312550114167 (diff) | |
| download | lwn-37bc15020a96035cb157be5864b958672fe02d7c.tar.gz lwn-37bc15020a96035cb157be5864b958672fe02d7c.zip | |
mm/sparse.c: introduce a new function clear_subsection_map()
Factor out the code which clear subsection map of one memory region from
section_deactivate() into clear_subsection_map().
And also add helper function is_subsection_map_empty() to check if the
current subsection map is empty or not.
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Link: http://lkml.kernel.org/r/20200312124414.439-3-bhe@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/sparse.c')
| -rw-r--r-- | mm/sparse.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/mm/sparse.c b/mm/sparse.c index 51965d56cd39..01204c3b4649 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -705,15 +705,11 @@ 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) +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; - bool empty; unsigned long *subsection_map = ms->usage ? &ms->usage->subsection_map[0] : NULL; @@ -724,8 +720,28 @@ 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); + return 0; +} + +static bool is_subsection_map_empty(struct mem_section *ms) +{ + return bitmap_empty(&ms->usage->subsection_map[0], + SUBSECTIONS_PER_SECTION); +} + +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; + bool empty; + + if (clear_subsection_map(pfn, nr_pages)) + return; /* * There are 3 cases to handle across two configurations * (SPARSEMEM_VMEMMAP={y,n}): @@ -743,8 +759,7 @@ 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); - empty = bitmap_empty(subsection_map, SUBSECTIONS_PER_SECTION); + empty = is_subsection_map_empty(ms); if (empty) { unsigned long section_nr = pfn_to_section_nr(pfn); |