diff options
| author | Rik van Riel <riel@surriel.com> | 2020-04-01 21:10:31 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-04-02 09:35:31 -0700 |
| commit | 1da2f328fa643bd72197dfed0c655148af31e4eb (patch) | |
| tree | 8eb87b7c293ea3cfa37d8e1f1a42c119332886c6 /mm/compaction.c | |
| parent | b06eda091e5d65bbfce183ad3403ab3d153bef9f (diff) | |
| download | linux-1da2f328fa643bd72197dfed0c655148af31e4eb.tar.bz2 | |
mm,thp,compaction,cma: allow THP migration for CMA allocations
The code to implement THP migrations already exists, and the code for CMA
to clear out a region of memory already exists.
Only a few small tweaks are needed to allow CMA to move THP memory when
attempting an allocation from alloc_contig_range.
With these changes, migrating THPs from a CMA area works when allocating a
1GB hugepage from CMA memory.
[riel@surriel.com: fix hugetlbfs pages per Mike, cleanup per Vlastimil]
Link: http://lkml.kernel.org/r/20200228104700.0af2f18d@imladris.surriel.com
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Link: http://lkml.kernel.org/r/20200227213238.1298752-2-riel@surriel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/compaction.c')
| -rw-r--r-- | mm/compaction.c | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index 672d3c78c6ab..000ade085b89 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -894,12 +894,13 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, /* * Regardless of being on LRU, compound pages such as THP and - * hugetlbfs are not to be compacted. We can potentially save - * a lot of iterations if we skip them at once. The check is - * racy, but we can consider only valid values and the only - * danger is skipping too much. + * hugetlbfs are not to be compacted unless we are attempting + * an allocation much larger than the huge page size (eg CMA). + * We can potentially save a lot of iterations if we skip them + * at once. The check is racy, but we can consider only valid + * values and the only danger is skipping too much. */ - if (PageCompound(page)) { + if (PageCompound(page) && !cc->alloc_contig) { const unsigned int order = compound_order(page); if (likely(order < MAX_ORDER)) @@ -969,7 +970,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, * and it's on LRU. It can only be a THP so the order * is safe to read and it's 0 for tail pages. */ - if (unlikely(PageCompound(page))) { + if (unlikely(PageCompound(page) && !cc->alloc_contig)) { low_pfn += compound_nr(page) - 1; goto isolate_fail; } @@ -981,12 +982,15 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, if (__isolate_lru_page(page, isolate_mode) != 0) goto isolate_fail; - VM_BUG_ON_PAGE(PageCompound(page), page); + /* The whole page is taken off the LRU; skip the tail pages. */ + if (PageCompound(page)) + low_pfn += compound_nr(page) - 1; /* Successfully isolated */ del_page_from_lru_list(page, lruvec, page_lru(page)); - inc_node_page_state(page, - NR_ISOLATED_ANON + page_is_file_cache(page)); + mod_node_page_state(page_pgdat(page), + NR_ISOLATED_ANON + page_is_file_cache(page), + hpage_nr_pages(page)); isolate_success: list_add(&page->lru, &cc->migratepages); |