From d2d243df445a88c26e91eac02b041213c7a32e9e Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Sun, 22 Sep 2024 12:32:13 +0800 Subject: mm: shmem: fix khugepaged activation policy for shmem Shmem has a separate interface (different from anonymous pages) to control huge page allocation, that means shmem THP can be enabled while anonymous THP is disabled. However, in this case, khugepaged will not start to collapse shmem THP, which is unreasonable. To fix this issue, we should call start_stop_khugepaged() to activate or deactivate the khugepaged thread when setting shmem mTHP interfaces. Moreover, add a new helper shmem_hpage_pmd_enabled() to help to check whether shmem THP is enabled, which will determine if khugepaged should be activated. Link: https://lkml.kernel.org/r/9b9c6cbc4499bf44c6455367fd9e0f6036525680.1726978977.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang Reported-by: Ryan Roberts Reviewed-by: Ryan Roberts Cc: David Hildenbrand Cc: Hugh Dickins Cc: Matthew Wilcox Signed-off-by: Andrew Morton --- include/linux/shmem_fs.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux') diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index 515a9a6a3c6f..ee6635052383 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -114,6 +114,7 @@ int shmem_unuse(unsigned int type); unsigned long shmem_allowable_huge_orders(struct inode *inode, struct vm_area_struct *vma, pgoff_t index, loff_t write_end, bool shmem_huge_force); +bool shmem_hpage_pmd_enabled(void); #else static inline unsigned long shmem_allowable_huge_orders(struct inode *inode, struct vm_area_struct *vma, pgoff_t index, @@ -121,6 +122,11 @@ static inline unsigned long shmem_allowable_huge_orders(struct inode *inode, { return 0; } + +static inline bool shmem_hpage_pmd_enabled(void) +{ + return false; +} #endif #ifdef CONFIG_SHMEM -- cgit v1.2.3-70-g09d2