From: Barry Song v-songbaohua@oppo.com
next inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9OCYO CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Fallback rates surpassing 90% have been observed on phones utilizing 64KiB CONT-PTE mTHP. In these scenarios, when one out of every 16 PTEs fails to allocate large folios, the remaining 15 PTEs fallback. Consequently, invoking vma_thp_gfp_mask seems redundant in such cases. Furthermore, abstaining from its use can also contribute to improved code readability.
Link: https://lkml.kernel.org/r/20240329073750.20012-1-21cnbao@gmail.com Signed-off-by: Barry Song v-songbaohua@oppo.com Reviewed-by: Zi Yan ziy@nvidia.com Acked-by: Yu Zhao yuzhao@google.com Reviewed-by: Ryan Roberts ryan.roberts@arm.com Cc: Kefeng Wang wangkefeng.wang@huawei.com Cc: John Hubbard jhubbard@nvidia.com Cc: David Hildenbrand david@redhat.com Cc: Alistair Popple apopple@nvidia.com Cc: Anshuman Khandual anshuman.khandual@arm.com Cc: Catalin Marinas catalin.marinas@arm.com Cc: David Rientjes rientjes@google.com Cc: "Huang, Ying" ying.huang@intel.com Cc: Hugh Dickins hughd@google.com Cc: Itaru Kitayama itaru.kitayama@gmail.com Cc: Kirill A. Shutemov kirill.shutemov@linux.intel.com Cc: Luis Chamberlain mcgrof@kernel.org Cc: Matthew Wilcox (Oracle) willy@infradead.org Cc: Vlastimil Babka vbabka@suse.cz Cc: Yang Shi shy828301@gmail.com Cc: Yin Fengwei fengwei.yin@intel.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Liu Shixin liushixin2@huawei.com --- mm/memory.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/mm/memory.c b/mm/memory.c index 2a0280384b67..dcb94f8eefb2 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4338,6 +4338,9 @@ static struct folio *alloc_anon_folio(struct vm_fault *vmf)
pte_unmap(pte);
+ if (!orders) + goto fallback; + /* Try allocating the highest of the remaining orders. */ gfp = vma_thp_gfp_mask(vma); while (orders) {