From e4544b63a7ee49e7fbebf35ece0a6acd3b9617ae Mon Sep 17 00:00:00 2001 From: Tim Murray Date: Fri, 7 Jan 2022 12:48:44 -0800 Subject: f2fs: move f2fs to use reader-unfair rwsems f2fs rw_semaphores work better if writers can starve readers, especially for the checkpoint thread, because writers are strictly more important than reader threads. This prevents significant priority inversion between low-priority readers that blocked while trying to acquire the read lock and a second acquisition of the write lock that might be blocking high priority work. Signed-off-by: Tim Murray Signed-off-by: Jaegeuk Kim --- fs/f2fs/checkpoint.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) (limited to 'fs/f2fs/checkpoint.c') diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 982f0170639f..deeda95688f0 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -351,13 +351,13 @@ static int f2fs_write_meta_pages(struct address_space *mapping, goto skip_write; /* if locked failed, cp will flush dirty pages instead */ - if (!down_write_trylock(&sbi->cp_global_sem)) + if (!f2fs_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); - up_write(&sbi->cp_global_sem); + f2fs_up_write(&sbi->cp_global_sem); wbc->nr_to_write = max((long)0, wbc->nr_to_write - written - diff); return 0; @@ -1159,7 +1159,7 @@ static bool __need_flush_quota(struct f2fs_sb_info *sbi) if (!is_journalled_quota(sbi)) return false; - if (!down_write_trylock(&sbi->quota_sem)) + if (!f2fs_down_write_trylock(&sbi->quota_sem)) return true; if (is_sbi_flag_set(sbi, SBI_QUOTA_SKIP_FLUSH)) { ret = false; @@ -1171,7 +1171,7 @@ static bool __need_flush_quota(struct f2fs_sb_info *sbi) } else if (get_pages(sbi, F2FS_DIRTY_QDATA)) { ret = true; } - up_write(&sbi->quota_sem); + f2fs_up_write(&sbi->quota_sem); return ret; } @@ -1228,10 +1228,10 @@ retry_flush_dents: * POR: we should ensure that there are no dirty node pages * until finishing nat/sit flush. inode->i_blocks can be updated. */ - down_write(&sbi->node_change); + f2fs_down_write(&sbi->node_change); if (get_pages(sbi, F2FS_DIRTY_IMETA)) { - up_write(&sbi->node_change); + f2fs_up_write(&sbi->node_change); f2fs_unlock_all(sbi); err = f2fs_sync_inode_meta(sbi); if (err) @@ -1241,15 +1241,15 @@ retry_flush_dents: } retry_flush_nodes: - down_write(&sbi->node_write); + f2fs_down_write(&sbi->node_write); if (get_pages(sbi, F2FS_DIRTY_NODES)) { - up_write(&sbi->node_write); + f2fs_up_write(&sbi->node_write); atomic_inc(&sbi->wb_sync_req[NODE]); err = f2fs_sync_node_pages(sbi, &wbc, false, FS_CP_NODE_IO); atomic_dec(&sbi->wb_sync_req[NODE]); if (err) { - up_write(&sbi->node_change); + f2fs_up_write(&sbi->node_change); f2fs_unlock_all(sbi); return err; } @@ -1262,13 +1262,13 @@ retry_flush_nodes: * dirty node blocks and some checkpoint values by block allocation. */ __prepare_cp_block(sbi); - up_write(&sbi->node_change); + f2fs_up_write(&sbi->node_change); return err; } static void unblock_operations(struct f2fs_sb_info *sbi) { - up_write(&sbi->node_write); + f2fs_up_write(&sbi->node_write); f2fs_unlock_all(sbi); } @@ -1612,7 +1612,7 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) f2fs_warn(sbi, "Start checkpoint disabled!"); } if (cpc->reason != CP_RESIZE) - down_write(&sbi->cp_global_sem); + f2fs_down_write(&sbi->cp_global_sem); if (!is_sbi_flag_set(sbi, SBI_IS_DIRTY) && ((cpc->reason & CP_FASTBOOT) || (cpc->reason & CP_SYNC) || @@ -1693,7 +1693,7 @@ stop: trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish checkpoint"); out: if (cpc->reason != CP_RESIZE) - up_write(&sbi->cp_global_sem); + f2fs_up_write(&sbi->cp_global_sem); return err; } @@ -1741,9 +1741,9 @@ static int __write_checkpoint_sync(struct f2fs_sb_info *sbi) struct cp_control cpc = { .reason = CP_SYNC, }; int err; - down_write(&sbi->gc_lock); + f2fs_down_write(&sbi->gc_lock); err = f2fs_write_checkpoint(sbi, &cpc); - up_write(&sbi->gc_lock); + f2fs_up_write(&sbi->gc_lock); return err; } @@ -1831,9 +1831,9 @@ int f2fs_issue_checkpoint(struct f2fs_sb_info *sbi) if (!test_opt(sbi, MERGE_CHECKPOINT) || cpc.reason != CP_SYNC) { int ret; - down_write(&sbi->gc_lock); + f2fs_down_write(&sbi->gc_lock); ret = f2fs_write_checkpoint(sbi, &cpc); - up_write(&sbi->gc_lock); + f2fs_up_write(&sbi->gc_lock); return ret; } -- cgit v1.2.3