diff options
author | Frank van der Linden <fvdl@google.com> | 2024-04-04 19:25:15 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-06-16 14:51:07 +0300 |
commit | a68ebd3dcd44e26e8e13b181a80628dacc16b8b7 (patch) | |
tree | c6c19d96bac2e24bbb798faf4bb8e2c1213cfa83 /fs/udf | |
parent | 012998e21f578af06db3b9ee66a7762692640f80 (diff) | |
download | linux-a68ebd3dcd44e26e8e13b181a80628dacc16b8b7.tar.xz |
mm/hugetlb: pass correct order_per_bit to cma_declare_contiguous_nid
commit 55d134a7b499c77e7cfd0ee41046f3c376e791e5 upstream.
The hugetlb_cma code passes 0 in the order_per_bit argument to
cma_declare_contiguous_nid (the alignment, computed using the page order,
is correctly passed in).
This causes a bit in the cma allocation bitmap to always represent a 4k
page, making the bitmaps potentially very large, and slower.
It would create bitmaps that would be pretty big. E.g. for a 4k page
size on x86, hugetlb_cma=64G would mean a bitmap size of (64G / 4k) / 8
== 2M. With HUGETLB_PAGE_ORDER as order_per_bit, as intended, this
would be (64G / 2M) / 8 == 4k. So, that's quite a difference.
Also, this restricted the hugetlb_cma area to ((PAGE_SIZE <<
MAX_PAGE_ORDER) * 8) * PAGE_SIZE (e.g. 128G on x86) , since
bitmap_alloc uses normal page allocation, and is thus restricted by
MAX_PAGE_ORDER. Specifying anything about that would fail the CMA
initialization.
So, correctly pass in the order instead.
Link: https://lkml.kernel.org/r/20240404162515.527802-2-fvdl@google.com
Fixes: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma")
Signed-off-by: Frank van der Linden <fvdl@google.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/udf')
0 files changed, 0 insertions, 0 deletions