* + mm-sparse-only-sub-section-aligned-range-would-be-populated.patch added to -mm tree
@ 2020-07-03 4:08 akpm
0 siblings, 0 replies; only message in thread
From: akpm @ 2020-07-03 4:08 UTC (permalink / raw)
To: david, mm-commits, richard.weiyang
The patch titled
Subject: mm/sparse: only sub-section aligned range would be populated
has been added to the -mm tree. Its filename is
mm-sparse-only-sub-section-aligned-range-would-be-populated.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-sparse-only-sub-section-aligned-range-would-be-populated.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-sparse-only-sub-section-aligned-range-would-be-populated.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Wei Yang <richard.weiyang@linux.alibaba.com>
Subject: mm/sparse: only sub-section aligned range would be populated
There are two code path which invoke __populate_section_memmap()
* sparse_init_nid()
* sparse_add_section()
For both case, we are sure the memory range is sub-section aligned.
* we pass PAGES_PER_SECTION to sparse_init_nid()
* we check range by check_pfn_span() before calling
sparse_add_section()
Also, the counterpart of __populate_section_memmap(), we don't do such
calculation and check since the range is checked by check_pfn_span() in
__remove_pages().
Clear the calculation and check to keep it simple and comply with its
counterpart.
Link: http://lkml.kernel.org/r/20200703031828.14645-1-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/sparse-vmemmap.c | 18 +++++-------------
1 file changed, 5 insertions(+), 13 deletions(-)
--- a/mm/sparse-vmemmap.c~mm-sparse-only-sub-section-aligned-range-would-be-populated
+++ a/mm/sparse-vmemmap.c
@@ -247,20 +247,12 @@ int __meminit vmemmap_populate_basepages
struct page * __meminit __populate_section_memmap(unsigned long pfn,
unsigned long nr_pages, int nid, struct vmem_altmap *altmap)
{
- unsigned long start;
- unsigned long end;
+ unsigned long start = (unsigned long) pfn_to_page(pfn);
+ unsigned long end = start + nr_pages * sizeof(struct page);
- /*
- * The minimum granularity of memmap extensions is
- * PAGES_PER_SUBSECTION as allocations are tracked in the
- * 'subsection_map' bitmap of the section.
- */
- end = ALIGN(pfn + nr_pages, PAGES_PER_SUBSECTION);
- pfn &= PAGE_SUBSECTION_MASK;
- nr_pages = end - pfn;
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2020-07-03 4:08 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-03 4:08 + mm-sparse-only-sub-section-aligned-range-would-be-populated.patch added to -mm tree akpm
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).