kernel/linux.git/fs/nilfs2/bmap.c, branch v6.12.80

nilfs2: fix missing initial short descriptions of kernel-doc comments

2024-09-02T03:43:37+00:00

Update some kernel-doc comments that are missing the initial short description and fix the following warnings output by the kernel-doc script: fs/nilfs2/bmap.c:353: warning: missing initial short description on line: * nilfs_bmap_lookup_dirty_buffers - fs/nilfs2/cpfile.c:708: warning: missing initial short description on line: * nilfs_cpfile_delete_checkpoint - fs/nilfs2/cpfile.c:972: warning: missing initial short description on line: * nilfs_cpfile_is_snapshot - fs/nilfs2/dat.c:275: warning: missing initial short description on line: * nilfs_dat_mark_dirty - fs/nilfs2/sufile.c:844: warning: missing initial short description on line: * nilfs_sufile_get_suinfo - Link: https://lkml.kernel.org/r/20240816074319.3253-9-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton

nilfs2: drop usage of page_index

2024-07-04T02:29:54+00:00

Patch series "mm/swap: clean up and optimize swap cache index", v6. Currently we use one swap_address_space for every 64M chunk to reduce lock contention, this is like having a set of smaller files inside a swap device. But when doing swap cache look up or insert, we are still using the offset of the whole large swap device. This is OK for correctness, as the offset (key) is unique. But Xarray is specially optimized for small indexes, it creates the redix tree levels lazily to be just enough to fit the largest key stored in one Xarray. So we are wasting tree nodes unnecessarily. For 64M chunk it should only take at most 3 level to contain everything. But if we are using the offset from the whole swap device, the offset (key) value will be way beyond 64M, and so will the tree level. Optimize this by reduce the swap cache search space into 64M scope. Test with `time memhog 128G` inside a 8G memcg using 128G swap (ramdisk with SWP_SYNCHRONOUS_IO dropped, tested 3 times, results are stable. The test result is similar but the improvement is smaller if SWP_SYNCHRONOUS_IO is enabled, as swap out path can never skip swap cache): Before: 6.07user 250.74system 4:17.26elapsed 99%CPU (0avgtext+0avgdata 8373376maxresident)k 0inputs+0outputs (55major+33555018minor)pagefaults 0swaps After (+1.8% faster): 6.08user 246.09system 4:12.58elapsed 99%CPU (0avgtext+0avgdata 8373248maxresident)k 0inputs+0outputs (54major+33555027minor)pagefaults 0swaps Similar result with MySQL and sysbench using swap: Before: 94055.61 qps After (+0.8% faster): 94834.91 qps There is alse a very slight drop of radix tree node slab usage: Before: 303952K After: 302224K For this series: There are multiple places that expect mixed type of pages (page cache or swap cache), eg. migration, huge memory split; There are four helpers for that: - page_index - page_file_offset - folio_index - folio_file_pos To keep the code clean and compatible, this series first cleaned up usage of them. page_file_offset and folio_file_pos are historical helpes that can be simply dropped after clean up. And page_index can be all converted to folio_index or folio->index. Then introduce two new helpers swap_cache_index and swap_dev_pos for swap. Replace swp_offset with swap_cache_index when used to retrieve folio from swap cache, and use swap_dev_pos when needed to retrieve the device position of a swap entry. This way, swap_cache_index can return the optimized value with no compatibility issue. The result is better performance and reduced LOC. Idealy, in the future, we may want to reduce SWAP_ADDRESS_SPACE_SHIFT from 14 to 12: Default Xarray chunk offset is 6, so we have 3 level trees instead of 2 level trees just for 2 extra bits. But swap cache is based on address_space struct, with 4 times more metadata sparsely distributed in memory it waste more cacheline, the performance gain from this series is almost canceled according to my test. So first, just have a cleaner seperation of offsets and smaller search space. This patch (of 10): page_index is only for mixed usage of page cache and swap cache, for pure page cache usage, the caller can just use page->index instead. It can't be a swap cache page here (being part of buffer head), so just drop it. And while we are at it, optimize the code by retrieving the offset of the buffer head within the folio directly using bh_offset, and get rid of the loop and usage of page helpers. Link: https://lkml.kernel.org/r/20240521175854.96038-1-ryncsn@gmail.com Link: https://lkml.kernel.org/r/20240521175854.96038-3-ryncsn@gmail.com Suggested-by: Matthew Wilcox Signed-off-by: Kairui Song Acked-by: Ryusuke Konishi Cc: Ryusuke Konishi Cc: Anna Schumaker Cc: Barry Song Cc: Chao Yu Cc: Chris Li Cc: David Hildenbrand Cc: David Howells Cc: "Huang, Ying" Cc: Hugh Dickins Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jeff Layton Cc: Marc Dionne Cc: Minchan Kim Cc: NeilBrown Cc: Ryan Roberts Cc: Trond Myklebust Cc: Xiubo Li Cc: Yosry Ahmed Signed-off-by: Andrew Morton

nilfs2: do not acquire rwsem in nilfs_bmap_write()

2024-02-22T23:38:53+00:00

It is now clear that nilfs_bmap_write() is only used to finalize logs written to disk. Concurrent bmap modification operations are not performed on bmaps in this context. Additionally, this function does not modify data used in read-only operations such as bmap lookups. Therefore, there is no need to acquire bmap->b_sem in nilfs_bmap_write(), so delete it. Link: https://lkml.kernel.org/r/20240122140202.6950-10-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton

nilfs2: fix infinite loop in nilfs_mdt_get_block()

2023-05-06T17:10:07+00:00

If the disk image that nilfs2 mounts is corrupted and a virtual block address obtained by block lookup for a metadata file is invalid, nilfs_bmap_lookup_at_level() may return the same internal return code as -ENOENT, meaning the block does not exist in the metadata file. This duplication of return codes confuses nilfs_mdt_get_block(), causing it to read and create a metadata block indefinitely. In particular, if this happens to the inode metadata file, ifile, semaphore i_rwsem can be left held, causing task hangs in lock_mount. Fix this issue by making nilfs_bmap_lookup_at_level() treat virtual block address translation failures with -ENOENT as metadata corruption instead of returning the error code. Link: https://lkml.kernel.org/r/20230430193046.6769-1-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi Tested-by: Ryusuke Konishi Reported-by: syzbot+221d75710bde87fa0e97@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=221d75710bde87fa0e97 Cc: Signed-off-by: Andrew Morton

nilfs2: remove filenames from file comments

2021-11-09T18:02:52+00:00

Remove filenames that are not particularly useful in file comments, and suppress checkpatch warnings WARNING: It's generally not useful to have the filename in the file Link: https://lkml.kernel.org/r/1635151862-11547-3-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi Cc: Qing Wang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: fix some kernel-doc warnings for nilfs2

2020-10-16T18:11:22+00:00

Fixes the following W=1 kernel build warning(s): fs/nilfs2/bmap.c:378: warning: Excess function parameter 'bhp' description in 'nilfs_bmap_assign' fs/nilfs2/cpfile.c:907: warning: Excess function parameter 'status' description in 'nilfs_cpfile_change_cpmode' fs/nilfs2/cpfile.c:946: warning: Excess function parameter 'stat' description in 'nilfs_cpfile_get_stat' fs/nilfs2/page.c:76: warning: Excess function parameter 'inode' description in 'nilfs_forget_buffer' fs/nilfs2/sufile.c:563: warning: Excess function parameter 'stat' description in 'nilfs_sufile_get_stat' Signed-off-by: Wang Hai Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Link: https://lkml.kernel.org/r/1601386269-2423-1-git-send-email-konishi.ryusuke@gmail.com Signed-off-by: Linus Torvalds

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

nilfs2: convert to SPDX license tags

2018-09-04T23:45:02+00:00

Remove the verbose license text from NILFS2 files and replace them with SPDX tags. This does not change the license of any of the code. Link: http://lkml.kernel.org/r/1535624528-5982-1-git-send-email-konishi.ryusuke@lab.ntt.co.jp Signed-off-by: Ryusuke Konishi Reviewed-by: Andrew Morton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: hide function name argument from nilfs_error()

2016-08-02T23:35:16+00:00

Simplify nilfs_error(), an output function used to report critical issues in file system. This renames the original nilfs_error() function to __nilfs_error() and redefines it as a macro to hide its function name argument within the macro. Every call site of nilfs_error() is changed to strip __func__ argument except nilfs_bmap_convert_error(); nilfs_bmap_convert_error() directly calls __nilfs_error() because it inherits caller's function name. Link: http://lkml.kernel.org/r/1464875891-5443-2-git-send-email-konishi.ryusuke@lab.ntt.co.jp Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

nilfs2: avoid bare use of 'unsigned'

2016-05-24T00:04:14+00:00

This fixes checkpatch.pl warning "WARNING: Prefer 'unsigned int' to bare use of 'unsigned'". Link: http://lkml.kernel.org/r/1462886671-3521-5-git-send-email-konishi.ryusuke@lab.ntt.co.jp Signed-off-by: Ryusuke Konishi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds