From cd21cc9af7eee791cc4d71a7b348518a46254ded Mon Sep 17 00:00:00 2001 From: Sahitya Tummala Date: Mon, 23 Nov 2020 10:58:32 +0530 Subject: [PATCH] f2fs: change to use rwsem for cp_mutex Use rwsem to ensure serialization of the callers and to avoid starvation of high priority tasks, when the system is under heavy IO workload. Signed-off-by: Sahitya Tummala Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/checkpoint.c | 8 ++++---- fs/f2fs/f2fs.h | 2 +- fs/f2fs/gc.c | 4 ++-- fs/f2fs/recovery.c | 4 ++-- fs/f2fs/super.c | 2 +- 5 files changed, 10 insertions(+), 10 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 9b0628e0d8bc..e5d2ffa80b56 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -348,13 +348,13 @@ static int f2fs_write_meta_pages(struct address_space *mapping, goto skip_write; /* if locked failed, cp will flush dirty pages instead */ - if (!mutex_trylock(&sbi->cp_mutex)) + if (!down_write_trylock(&sbi->cp_global_sem)) goto skip_write; trace_f2fs_writepages(mapping->host, wbc, META); diff = nr_pages_to_write(sbi, META, wbc); written = f2fs_sync_meta_pages(sbi, META, wbc->nr_to_write, FS_META_IO); - mutex_unlock(&sbi->cp_mutex); + up_write(&sbi->cp_global_sem); wbc->nr_to_write = max((long)0, wbc->nr_to_write - written - diff); return 0; @@ -1572,7 +1572,7 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) f2fs_warn(sbi, "Start checkpoint disabled!"); } if (cpc->reason != CP_RESIZE) - mutex_lock(&sbi->cp_mutex); + down_write(&sbi->cp_global_sem); if (!is_sbi_flag_set(sbi, SBI_IS_DIRTY) && ((cpc->reason & CP_FASTBOOT) || (cpc->reason & CP_SYNC) || @@ -1647,7 +1647,7 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish checkpoint"); out: if (cpc->reason != CP_RESIZE) - mutex_unlock(&sbi->cp_mutex); + up_write(&sbi->cp_global_sem); return err; } diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 51a44ee1ddf2..bbda309f9e22 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1373,7 +1373,7 @@ struct f2fs_sb_info { int cur_cp_pack; /* remain current cp pack */ spinlock_t cp_lock; /* for flag in ckpt */ struct inode *meta_inode; /* cache meta blocks */ - struct mutex cp_mutex; /* checkpoint procedure lock */ + struct rw_semaphore cp_global_sem; /* checkpoint procedure lock */ struct rw_semaphore cp_rwsem; /* blocking FS operations */ struct rw_semaphore node_write; /* locking node writes */ struct rw_semaphore node_change; /* locking node change */ diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index 05641a1e36cc..3ef84e6ded41 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -1986,7 +1986,7 @@ int f2fs_resize_fs(struct f2fs_sb_info *sbi, __u64 block_count) freeze_super(sbi->sb); down_write(&sbi->gc_lock); - mutex_lock(&sbi->cp_mutex); + down_write(&sbi->cp_global_sem); spin_lock(&sbi->stat_lock); if (shrunk_blocks + valid_user_blocks(sbi) + @@ -2031,7 +2031,7 @@ int f2fs_resize_fs(struct f2fs_sb_info *sbi, __u64 block_count) spin_unlock(&sbi->stat_lock); } out_err: - mutex_unlock(&sbi->cp_mutex); + up_write(&sbi->cp_global_sem); up_write(&sbi->gc_lock); thaw_super(sbi->sb); clear_sbi_flag(sbi, SBI_IS_RESIZEFS); diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c index bf624dfa18af..a80526f4fed0 100644 --- a/fs/f2fs/recovery.c +++ b/fs/f2fs/recovery.c @@ -798,7 +798,7 @@ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only) INIT_LIST_HEAD(&dir_list); /* prevent checkpoint */ - mutex_lock(&sbi->cp_mutex); + down_write(&sbi->cp_global_sem); /* step #1: find fsynced inode numbers */ err = find_fsync_dnodes(sbi, &inode_list, check_only); @@ -834,7 +834,7 @@ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only) } else { clear_sbi_flag(sbi, SBI_POR_DOING); } - mutex_unlock(&sbi->cp_mutex); + up_write(&sbi->cp_global_sem); /* let's drop all the directory inodes for clean checkpoint */ destroy_fsync_dnodes(&dir_list, err); diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 258dbd31be40..a04ad9610d47 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -3511,7 +3511,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) sbi->valid_super_block = valid_super_block; init_rwsem(&sbi->gc_lock); mutex_init(&sbi->writepages); - mutex_init(&sbi->cp_mutex); + init_rwsem(&sbi->cp_global_sem); init_rwsem(&sbi->node_write); init_rwsem(&sbi->node_change);