From 1720f5dd8d3af34d6023fb9e8c35e5e60e8b6643 Mon Sep 17 00:00:00 2001 From: Qi Zheng Date: Mon, 11 Sep 2023 17:44:37 +0800 Subject: fs: super: dynamically allocate the s_shrink In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the s_shrink, so that it can be freed asynchronously via RCU. Then it doesn't need to wait for RCU read-side critical section when releasing the struct super_block. Link: https://lkml.kernel.org/r/20230911094444.68966-39-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Reviewed-by: Muchun Song Acked-by: David Sterba Cc: Chris Mason Cc: Josef Bacik Cc: Alexander Viro Cc: Christian Brauner Cc: Abhinav Kumar Cc: Alasdair Kergon Cc: Alyssa Rosenzweig Cc: Andreas Dilger Cc: Andreas Gruenbacher Cc: Anna Schumaker Cc: Arnd Bergmann Cc: Bob Peterson Cc: Borislav Petkov Cc: Carlos Llamas Cc: Chandan Babu R Cc: Chao Yu Cc: Christian Koenig Cc: Chuck Lever Cc: Coly Li Cc: Dai Ngo Cc: Daniel Vetter Cc: Daniel Vetter Cc: "Darrick J. Wong" Cc: Dave Chinner Cc: Dave Hansen Cc: David Airlie Cc: David Hildenbrand Cc: Dmitry Baryshkov Cc: Gao Xiang Cc: Greg Kroah-Hartman Cc: Huang Rui Cc: Ingo Molnar Cc: Jaegeuk Kim Cc: Jani Nikula Cc: Jan Kara Cc: Jason Wang Cc: Jeff Layton Cc: Jeffle Xu Cc: Joel Fernandes (Google) Cc: Joonas Lahtinen Cc: Juergen Gross Cc: Kent Overstreet Cc: Kirill Tkhai Cc: Marijn Suijten Cc: "Michael S. Tsirkin" Cc: Mike Snitzer Cc: Minchan Kim Cc: Muchun Song Cc: Nadav Amit Cc: Neil Brown Cc: Oleksandr Tyshchenko Cc: Olga Kornievskaia Cc: Paul E. McKenney Cc: Richard Weinberger Cc: Rob Clark Cc: Rob Herring Cc: Rodrigo Vivi Cc: Roman Gushchin Cc: Sean Paul Cc: Sergey Senozhatsky Cc: Song Liu Cc: Stefano Stabellini Cc: Steven Price Cc: "Theodore Ts'o" Cc: Thomas Gleixner Cc: Tomeu Vizoso Cc: Tom Talpey Cc: Trond Myklebust Cc: Tvrtko Ursulin Cc: Vlastimil Babka Cc: Xuan Zhuo Cc: Yue Hu Signed-off-by: Andrew Morton --- fs/kernfs/mount.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/kernfs') diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c index c4bf26142eec..79b96e74a8a0 100644 --- a/fs/kernfs/mount.c +++ b/fs/kernfs/mount.c @@ -265,7 +265,7 @@ static int kernfs_fill_super(struct super_block *sb, struct kernfs_fs_context *k sb->s_time_gran = 1; /* sysfs dentries and inodes don't require IO to create */ - sb->s_shrink.seeks = 0; + sb->s_shrink->seeks = 0; /* get root inode, initialize and unlock it */ down_read(&kf_root->kernfs_rwsem); -- cgit v1.2.3-58-ga151 From 4b981bc1aa73c204c2aa7f99b5f4f74d03b0e381 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Tue, 3 Oct 2023 02:16:29 -0700 Subject: kernfs: drop shared NUMA mempolicy hooks It seems strange that kernfs should be an outlier with a set_policy and get_policy in its kernfs_vm_ops. Ah, it dates back to v2.6.30's commit 095160aee954 ("sysfs: fix some bin_vm_ops errors"), when I had crashed on powerpc's pci_mmap_legacy_page_range() fallback to shmem_zero_setup(). Well, that was commendably thorough, to give sysfs-bin a set_policy and get_policy, just to avoid the way it was coded resulting in EINVAL from mmap when CONFIG_NUMA; but somehow feels a bit over-the-top to me now. It's easier to say that nobody should expect to manage a shmem object's shared NUMA mempolicy via some kernfs backdoor to that object: delete that code (and there's no longer an EINVAL from mmap in the NUMA case). This then leaves set_policy/get_policy as implemented only by shmem - though importantly also by SysV SHM, which has to interface with shmem which implements them, and with SHM_HUGETLB which does not. Link: https://lkml.kernel.org/r/302164-a760-4a9e-879b-6870c9b4013@google.com Signed-off-by: Hugh Dickins Reviewed-by: Matthew Wilcox (Oracle) Cc: Andi Kleen Cc: Christoph Lameter Cc: David Hildenbrand Cc: Greg Kroah-Hartman Cc: "Huang, Ying" Cc: Kefeng Wang Cc: Mel Gorman Cc: Michal Hocko Cc: Mike Kravetz Cc: Nhat Pham Cc: Sidhartha Kumar Cc: Suren Baghdasaryan Cc: Tejun heo Cc: Vishal Moola (Oracle) Cc: Yang Shi Cc: Yosry Ahmed Signed-off-by: Andrew Morton --- fs/kernfs/file.c | 49 ------------------------------------------------- 1 file changed, 49 deletions(-) (limited to 'fs/kernfs') diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c index 180906c36f51..aaa76410e550 100644 --- a/fs/kernfs/file.c +++ b/fs/kernfs/file.c @@ -429,60 +429,11 @@ static int kernfs_vma_access(struct vm_area_struct *vma, unsigned long addr, return ret; } -#ifdef CONFIG_NUMA -static int kernfs_vma_set_policy(struct vm_area_struct *vma, - struct mempolicy *new) -{ - struct file *file = vma->vm_file; - struct kernfs_open_file *of = kernfs_of(file); - int ret; - - if (!of->vm_ops) - return 0; - - if (!kernfs_get_active(of->kn)) - return -EINVAL; - - ret = 0; - if (of->vm_ops->set_policy) - ret = of->vm_ops->set_policy(vma, new); - - kernfs_put_active(of->kn); - return ret; -} - -static struct mempolicy *kernfs_vma_get_policy(struct vm_area_struct *vma, - unsigned long addr) -{ - struct file *file = vma->vm_file; - struct kernfs_open_file *of = kernfs_of(file); - struct mempolicy *pol; - - if (!of->vm_ops) - return vma->vm_policy; - - if (!kernfs_get_active(of->kn)) - return vma->vm_policy; - - pol = vma->vm_policy; - if (of->vm_ops->get_policy) - pol = of->vm_ops->get_policy(vma, addr); - - kernfs_put_active(of->kn); - return pol; -} - -#endif - static const struct vm_operations_struct kernfs_vm_ops = { .open = kernfs_vma_open, .fault = kernfs_vma_fault, .page_mkwrite = kernfs_vma_page_mkwrite, .access = kernfs_vma_access, -#ifdef CONFIG_NUMA - .set_policy = kernfs_vma_set_policy, - .get_policy = kernfs_vma_get_policy, -#endif }; static int kernfs_fop_mmap(struct file *file, struct vm_area_struct *vma) -- cgit v1.2.3-58-ga151