kernel/linux.git/fs/f2fs/shrinker.c, branch v6.18.22

f2fs: handle error cases of memory donation

2025-05-06T15:46:55+00:00

In cases of removing memory donation, we need to handle some error cases like ENOENT and EACCES (indicating the range already has been donated). Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: add a sysfs entry to reclaim POSIX_FADV_NOREUSE pages

2025-02-13T17:58:36+00:00

1. fadvise(fd1, POSIX_FADV_NOREUSE, {0,3}); 2. fadvise(fd2, POSIX_FADV_NOREUSE, {1,2}); 3. fadvise(fd3, POSIX_FADV_NOREUSE, {3,1}); 4. echo 1024 > /sys/fs/f2fs/tuning/reclaim_caches_kb This gives a way to reclaim file-backed pages by iterating all f2fs mounts until reclaiming 1MB page cache ranges, registered by #1, #2, and #3. 5. cat /sys/fs/f2fs/tuning/reclaim_caches_kb -> gives total number of registered file ranges. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix to return SHRINK_EMPTY if no objects to free

2025-02-10T17:03:19+00:00

Quoted from include/linux/shrinker.h "count_objects should return the number of freeable items in the cache. If there are no objects to free, it should return SHRINK_EMPTY, while 0 is returned in cases of the number of freeable items cannot be determined or shrinker should skip this cache for this time (e.g., their number is below shrinkable limit)." Signed-off-by: Zhiguo Niu Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: add block_age-based extent cache

2022-12-12T22:53:56+00:00

This patch introduces a runtime hot/cold data separation method for f2fs, in order to improve the accuracy for data temperature classification, reduce the garbage collection overhead after long-term data updates. Enhanced hot/cold data separation can record data block update frequency as "age" of the extent per inode, and take use of the age info to indicate better temperature type for data block allocation: - It records total data blocks allocated since mount; - When file extent has been updated, it calculate the count of data blocks allocated since last update as the age of the extent; - Before the data block allocated, it searches for the age info and chooses the suitable segment for allocation. Test and result: - Prepare: create about 30000 files * 3% for cold files (with cold file extension like .apk, from 3M to 10M) * 50% for warm files (with random file extension like .FcDxq, from 1K to 4M) * 47% for hot files (with hot file extension like .db, from 1K to 256K) - create(5%)/random update(90%)/delete(5%) the files * total write amount is about 70G * fsync will be called for .db files, and buffered write will be used for other files The storage of test device is large enough(128G) so that it will not switch to SSR mode during the test. Benefit: dirty segment count increment reduce about 14% - before: Dirty +21110 - after: Dirty +18286 Signed-off-by: qixiaoyu1 Signed-off-by: xiongping1 Signed-off-by: Jaegeuk Kim

f2fs: refactor extent_cache to support for read and more

2022-12-12T22:53:56+00:00

This patch prepares extent_cache to be ready for addition. Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: avoid race condition for shrinker count

2020-12-03T08:59:26+00:00

Light reported sometimes shinker gets nat_cnt < dirty_nat_cnt resulting in wrong do_shinker work. Let's avoid to return insane overflowed value by adding single tracking value. Reported-by: Light Hsieh Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix inconsistent comments

2020-03-10T16:18:33+00:00

Lack of maintenance on comments may mislead developers, fix them. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix sbi->extent_list corruption issue

2018-12-26T23:16:54+00:00

When there is a failure in f2fs_fill_super() after/during the recovery of fsync'd nodes, it frees the current sbi and retries again. This time the mount is successful, but the files that got recovered before retry, still holds the extent tree, whose extent nodes list is corrupted since sbi and sbi->extent_list is freed up. The list_del corruption issue is observed when the file system is getting unmounted and when those recoverd files extent node is being freed up in the below context. list_del corruption. prev->next should be fffffff1e1ef5480, but was (null) <...> kernel BUG at kernel/msm-4.14/lib/list_debug.c:53! lr : __list_del_entry_valid+0x94/0xb4 pc : __list_del_entry_valid+0x94/0xb4 <...> Call trace: __list_del_entry_valid+0x94/0xb4 __release_extent_node+0xb0/0x114 __free_extent_tree+0x58/0x7c f2fs_shrink_extent_tree+0xdc/0x3b0 f2fs_leave_shrinker+0x28/0x7c f2fs_put_super+0xfc/0x1e0 generic_shutdown_super+0x70/0xf4 kill_block_super+0x2c/0x5c kill_f2fs_super+0x44/0x50 deactivate_locked_super+0x60/0x8c deactivate_super+0x68/0x74 cleanup_mnt+0x40/0x78 __cleanup_mnt+0x1c/0x28 task_work_run+0x48/0xd0 do_notify_resume+0x678/0xe98 work_pending+0x8/0x14 Fix this by not creating extents for those recovered files if shrinker is not registered yet. Once mount is successful and shrinker is registered, those files can have extents again. Signed-off-by: Sahitya Tummala Signed-off-by: Jaegeuk Kim

f2fs: add SPDX license identifiers

2018-09-12T20:07:10+00:00

Remove the verbose license text from f2fs files and replace them with SPDX tags. This does not change the license of any of the code. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: clean up symbol namespace

2018-05-31T18:31:53+00:00

As Ted reported: "Hi, I was looking at f2fs's sources recently, and I noticed that there is a very large number of non-static symbols which don't have a f2fs prefix. There's well over a hundred (see attached below). As one example, in fs/f2fs/dir.c there is: unsigned char get_de_type(struct f2fs_dir_entry *de) This function is clearly only useful for f2fs, but it has a generic name. This means that if any other file system tries to have the same symbol name, there will be a symbol conflict and the kernel would not successfully build. It also means that when someone is looking f2fs sources, it's not at all obvious whether a function such as read_data_page(), invalidate_blocks(), is a generic kernel function found in the fs, mm, or block layers, or a f2fs specific function. You might want to fix this at some point. Hopefully Kent's bcachefs isn't similarly using genericly named functions, since that might cause conflicts with f2fs's functions --- but just as this would be a problem that we would rightly insist that Kent fix, this is something that we should have rightly insisted that f2fs should have fixed before it was integrated into the mainline kernel. acquire_orphan_inode add_ino_entry add_orphan_inode allocate_data_block allocate_new_segments alloc_nid alloc_nid_done alloc_nid_failed available_free_memory ...." This patch adds "f2fs_" prefix for all non-static symbols in order to: a) avoid conflict with other kernel generic symbols; b) to indicate the function is f2fs specific one instead of generic one; Reported-by: Theodore Ts'o Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim