The patch titled
Subject: nilfs2: eliminate the shared counter and spinlock for i_generation
has been added to the -mm mm-nonmm-unstable branch. Its filename is
nilfs2-eliminate-the-shared-counter-and-spinlock-for-i_generation.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nilfs2-eliminate-the-shared-counter-and-spinlock-for-i_generation.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: eliminate the shared counter and spinlock for i_generation
Date: Tue, 27 Aug 2024 02:41:12 +0900
Use get_random_u32() as the source for inode->i_generation for new inodes,
and eliminate the original source, the shared counter ns_next_generation
along with its exclusive access spinlock ns_next_gen_lock.
Link: https://lkml.kernel.org/r/20240826174116.5008-5-konishi.ryusuke@xxxxxxxxx
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Cc: Huang Xiaojia <huangxiaojia2@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/nilfs2/inode.c | 6 ++----
fs/nilfs2/the_nilfs.c | 5 -----
fs/nilfs2/the_nilfs.h | 6 ------
3 files changed, 2 insertions(+), 15 deletions(-)
--- a/fs/nilfs2/inode.c~nilfs2-eliminate-the-shared-counter-and-spinlock-for-i_generation
+++ a/fs/nilfs2/inode.c
@@ -15,6 +15,7 @@
#include <linux/writeback.h>
#include <linux/uio.h>
#include <linux/fiemap.h>
+#include <linux/random.h>
#include "nilfs.h"
#include "btnode.h"
#include "segment.h"
@@ -320,7 +321,6 @@ static int nilfs_insert_inode_locked(str
struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
{
struct super_block *sb = dir->i_sb;
- struct the_nilfs *nilfs = sb->s_fs_info;
struct inode *inode;
struct nilfs_inode_info *ii;
struct nilfs_root *root;
@@ -381,9 +381,7 @@ struct inode *nilfs_new_inode(struct ino
/* ii->i_dir_acl = 0; */
ii->i_dir_start_lookup = 0;
nilfs_set_inode_flags(inode);
- spin_lock(&nilfs->ns_next_gen_lock);
- inode->i_generation = nilfs->ns_next_generation++;
- spin_unlock(&nilfs->ns_next_gen_lock);
+ inode->i_generation = get_random_u32();
if (nilfs_insert_inode_locked(inode, root, ino) < 0) {
err = -EIO;
goto failed_after_creation;
--- a/fs/nilfs2/the_nilfs.c~nilfs2-eliminate-the-shared-counter-and-spinlock-for-i_generation
+++ a/fs/nilfs2/the_nilfs.c
@@ -12,7 +12,6 @@
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
-#include <linux/random.h>
#include <linux/log2.h>
#include <linux/crc32.h>
#include "nilfs.h"
@@ -69,7 +68,6 @@ struct the_nilfs *alloc_nilfs(struct sup
INIT_LIST_HEAD(&nilfs->ns_dirty_files);
INIT_LIST_HEAD(&nilfs->ns_gc_inodes);
spin_lock_init(&nilfs->ns_inode_lock);
- spin_lock_init(&nilfs->ns_next_gen_lock);
spin_lock_init(&nilfs->ns_last_segment_lock);
nilfs->ns_cptree = RB_ROOT;
spin_lock_init(&nilfs->ns_cptree_lock);
@@ -754,9 +752,6 @@ int init_nilfs(struct the_nilfs *nilfs,
nilfs->ns_blocksize_bits = sb->s_blocksize_bits;
nilfs->ns_blocksize = blocksize;
- get_random_bytes(&nilfs->ns_next_generation,
- sizeof(nilfs->ns_next_generation));
-
err = nilfs_store_disk_layout(nilfs, sbp);
if (err)
goto failed_sbh;
--- a/fs/nilfs2/the_nilfs.h~nilfs2-eliminate-the-shared-counter-and-spinlock-for-i_generation
+++ a/fs/nilfs2/the_nilfs.h
@@ -71,8 +71,6 @@ enum {
* @ns_dirty_files: list of dirty files
* @ns_inode_lock: lock protecting @ns_dirty_files
* @ns_gc_inodes: dummy inodes to keep live blocks
- * @ns_next_generation: next generation number for inodes
- * @ns_next_gen_lock: lock protecting @ns_next_generation
* @ns_mount_opt: mount options
* @ns_resuid: uid for reserved blocks
* @ns_resgid: gid for reserved blocks
@@ -161,10 +159,6 @@ struct the_nilfs {
/* GC inode list */
struct list_head ns_gc_inodes;
- /* Inode allocator */
- u32 ns_next_generation;
- spinlock_t ns_next_gen_lock;
-
/* Mount options */
unsigned long ns_mount_opt;
_
Patches currently in -mm which might be from konishi.ryusuke@xxxxxxxxx are
nilfs2-protect-references-to-superblock-parameters-exposed-in-sysfs.patch
nilfs2-fix-missing-cleanup-on-rollforward-recovery-error.patch
nilfs2-fix-state-management-in-error-path-of-log-writing-function.patch
nilfs2-add-support-for-fs_ioc_getuuid.patch
nilfs2-add-support-for-fs_ioc_getfssysfspath.patch
nilfs2-add-support-for-fs_ioc_getfslabel.patch
nilfs2-add-support-for-fs_ioc_setfslabel.patch
nilfs2-do-not-output-warnings-when-clearing-dirty-buffers.patch
nilfs2-add-missing-argument-description-for-__nilfs_error.patch
nilfs2-add-missing-argument-descriptions-for-ioctl-related-helpers.patch
nilfs2-improve-kernel-doc-comments-for-b-tree-node-helpers.patch
nilfs2-fix-incorrect-kernel-doc-declaration-of-nilfs_palloc_req-structure.patch
nilfs2-add-missing-description-of-nilfs_btree_path-structure.patch
nilfs2-describe-the-members-of-nilfs_bmap_operations-structure.patch
nilfs2-fix-inconsistencies-in-kernel-doc-comments-in-segmenth.patch
nilfs2-fix-missing-initial-short-descriptions-of-kernel-doc-comments.patch
nilfs2-treat-missing-sufile-header-block-as-metadata-corruption.patch
nilfs2-treat-missing-cpfile-header-block-as-metadata-corruption.patch
nilfs2-do-not-propagate-enoent-error-from-sufile-during-recovery.patch
nilfs2-do-not-propagate-enoent-error-from-sufile-during-gc.patch
nilfs2-do-not-propagate-enoent-error-from-nilfs_sufile_mark_dirty.patch
nilfs2-use-the-bits_per_long-macro.patch
nilfs2-separate-inode-type-information-from-i_state-field.patch
nilfs2-eliminate-the-shared-counter-and-spinlock-for-i_generation.patch
nilfs2-do-not-repair-reserved-inode-bitmap-in-nilfs_new_inode.patch
nilfs2-remove-sc_timer_task.patch
nilfs2-use-kthread_create-and-kthread_stop-for-the-log-writer-thread.patch
nilfs2-refactor-nilfs_segctor_thread.patch
