The patch titled
Subject: nilfs2: do not acquire rwsem in nilfs_bmap_write()
has been added to the -mm mm-nonmm-unstable branch. Its filename is
nilfs2-do-not-acquire-rwsem-in-nilfs_bmap_write.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nilfs2-do-not-acquire-rwsem-in-nilfs_bmap_write.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Subject: nilfs2: do not acquire rwsem in nilfs_bmap_write()
Date: Mon, 22 Jan 2024 23:01:56 +0900
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@xxxxxxxxx
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/nilfs2/bmap.c | 3 ---
1 file changed, 3 deletions(-)
--- a/fs/nilfs2/bmap.c~nilfs2-do-not-acquire-rwsem-in-nilfs_bmap_write
+++ a/fs/nilfs2/bmap.c
@@ -548,13 +548,10 @@ int nilfs_bmap_read(struct nilfs_bmap *b
*/
void nilfs_bmap_write(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
{
- down_write(&bmap->b_sem);
memcpy(raw_inode->i_bmap, bmap->b_u.u_data,
NILFS_INODE_BMAP_SIZE * sizeof(__le64));
if (bmap->b_inode->i_ino == NILFS_DAT_INO)
bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
-
- up_write(&bmap->b_sem);
}
void nilfs_bmap_init_gc(struct nilfs_bmap *bmap)
_
Patches currently in -mm which might be from konishi.ryusuke@xxxxxxxxx are
nilfs2-convert-recovery-logic-to-use-kmap_local.patch
nilfs2-convert-segment-buffer-to-use-kmap_local.patch
nilfs2-convert-nilfs_copy_buffer-to-use-kmap_local.patch
nilfs2-convert-metadata-file-common-code-to-use-kmap_local.patch
nilfs2-convert-sufile-to-use-kmap_local.patch
nilfs2-convert-persistent-object-allocator-to-use-kmap_local.patch
nilfs2-convert-dat-to-use-kmap_local.patch
nilfs2-move-nilfs_bmap_write-call-out-of-nilfs_write_inode_common.patch
nilfs2-do-not-acquire-rwsem-in-nilfs_bmap_write.patch
nilfs2-convert-ifile-to-use-kmap_local.patch
nilfs2-localize-highmem-mapping-for-checkpoint-creation-within-cpfile.patch
nilfs2-localize-highmem-mapping-for-checkpoint-finalization-within-cpfile.patch
nilfs2-localize-highmem-mapping-for-checkpoint-reading-within-cpfile.patch
nilfs2-remove-nilfs_cpfile_getput_checkpoint.patch
nilfs2-convert-cpfile-to-use-kmap_local.patch
