From 769ec6e5b7d4a8115447736871be8bffaaba3a7d Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Wed, 3 Dec 2014 20:47:26 -0800 Subject: [PATCH] f2fs: call radix_tree_preload before radix_tree_insert This patch tries to fix: BUG: using smp_processor_id() in preemptible [00000000] code: f2fs_gc-254:0/384 (radix_tree_node_alloc+0x14/0x74) from [] (radix_tree_insert+0x110/0x200) (radix_tree_insert+0x110/0x200) from [] (gc_data_segment+0x340/0x52c) (gc_data_segment+0x340/0x52c) from [] (f2fs_gc+0x208/0x400) (f2fs_gc+0x208/0x400) from [] (gc_thread_func+0x248/0x28c) (gc_thread_func+0x248/0x28c) from [] (kthread+0xa0/0xac) (kthread+0xa0/0xac) from [] (ret_from_fork+0x14/0x3c) The reason is that f2fs calls radix_tree_insert under enabled preemption. So, before calling it, we need to call radix_tree_preload. Otherwise, we should use _GFP_WAIT for the radix tree, and use mutex or semaphore to cover the radix tree operations. Signed-off-by: Jaegeuk Kim --- fs/f2fs/checkpoint.c | 8 ++++++++ fs/f2fs/gc.c | 6 ++---- fs/f2fs/node.c | 11 +++++++++-- 3 files changed, 19 insertions(+), 6 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 20a917b05b9..6a81b73add0 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -304,6 +304,11 @@ static void __add_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type) struct inode_management *im = &sbi->im[type]; struct ino_entry *e; retry: + if (radix_tree_preload(GFP_NOFS)) { + cond_resched(); + goto retry; + } + spin_lock(&im->ino_lock); e = radix_tree_lookup(&im->ino_root, ino); @@ -311,11 +316,13 @@ retry: e = kmem_cache_alloc(ino_entry_slab, GFP_ATOMIC); if (!e) { spin_unlock(&im->ino_lock); + radix_tree_preload_end(); goto retry; } if (radix_tree_insert(&im->ino_root, ino, e)) { spin_unlock(&im->ino_lock); kmem_cache_free(ino_entry_slab, e); + radix_tree_preload_end(); goto retry; } memset(e, 0, sizeof(struct ino_entry)); @@ -326,6 +333,7 @@ retry: im->ino_num++; } spin_unlock(&im->ino_lock); + radix_tree_preload_end(); } static void __remove_ino_entry(struct f2fs_sb_info *sbi, nid_t ino, int type) diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index a1af74f1a1d..2c58c587a3c 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -351,7 +351,6 @@ static struct inode *find_gc_inode(struct gc_inode_list *gc_list, nid_t ino) static void add_gc_inode(struct gc_inode_list *gc_list, struct inode *inode) { struct inode_entry *new_ie; - int ret; if (inode == find_gc_inode(gc_list, inode->i_ino)) { iput(inode); @@ -361,8 +360,7 @@ retry: new_ie = f2fs_kmem_cache_alloc(winode_slab, GFP_NOFS); new_ie->inode = inode; - ret = radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie); - if (ret) { + if (radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie)) { kmem_cache_free(winode_slab, new_ie); goto retry; } @@ -703,7 +701,7 @@ int f2fs_gc(struct f2fs_sb_info *sbi) struct cp_control cpc; struct gc_inode_list gc_list = { .ilist = LIST_HEAD_INIT(gc_list.ilist), - .iroot = RADIX_TREE_INIT(GFP_ATOMIC), + .iroot = RADIX_TREE_INIT(GFP_NOFS), }; cpc.reason = test_opt(sbi, FASTBOOT) ? CP_UMOUNT : CP_SYNC; diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index b47555fe175..8de4f555d53 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1447,15 +1447,22 @@ static int add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build) i->nid = nid; i->state = NID_NEW; + if (radix_tree_preload(GFP_NOFS)) { + kmem_cache_free(free_nid_slab, i); + return 0; + } + spin_lock(&nm_i->free_nid_list_lock); if (radix_tree_insert(&nm_i->free_nid_root, i->nid, i)) { spin_unlock(&nm_i->free_nid_list_lock); + radix_tree_preload_end(); kmem_cache_free(free_nid_slab, i); return 0; } list_add_tail(&i->list, &nm_i->free_nid_list); nm_i->fcnt++; spin_unlock(&nm_i->free_nid_list_lock); + radix_tree_preload_end(); return 1; } @@ -1994,8 +2001,8 @@ static int init_node_manager(struct f2fs_sb_info *sbi) INIT_RADIX_TREE(&nm_i->free_nid_root, GFP_ATOMIC); INIT_LIST_HEAD(&nm_i->free_nid_list); - INIT_RADIX_TREE(&nm_i->nat_root, GFP_ATOMIC); - INIT_RADIX_TREE(&nm_i->nat_set_root, GFP_ATOMIC); + INIT_RADIX_TREE(&nm_i->nat_root, GFP_NOIO); + INIT_RADIX_TREE(&nm_i->nat_set_root, GFP_NOIO); INIT_LIST_HEAD(&nm_i->nat_entries); mutex_init(&nm_i->build_lock); -- 2.46.0