*2X3 -S;ʻԱu "f HsڌH^-/ׇPgݏ O)]ĕ7 RyY&c$R\dF8cr#L_Cz@}8$](,UȠ@o9kIzG4]oy6C!B_^ÑAyl?;" C Csp ySZ/@- WJ"O^?BQ8N./;ϙU!Bpq|e^/_jlK0bďR,:bRPd+RۅMGecc ErDbӫ ε_XN S6Z8G쉧b8 u+}+4Uɖ0A-X'v,UhҬ!xe:ؽ_{EMg]PXrPGҽ@:ZIv!yoI̧F]9C瓀 .?Ox45MJ"V WQˈBy;xr>[26콓- Oxc?ff,Xp)P $ Ő(\40HU@X Wn?O 8nT2Q t|E hM[uq R(zH&) R7pwK0|P;oX5 (kd >yEXWl 6Gǎ^VO8ߑ [ܾER$b%:4OUtĨ yẢB/ШG9њ3$ k?E*o 6z?- ^3ߒ )b`VXIXͻoR8Lޤ(z:˻bZg_|2sm, )AQ6`r-n.SR`:gɻ&-N6hY"xWCFԊ-e4`!+$| $U:K$S ֐pzc[iӂ(Tv C5Y$i)+|wt7.~)(z_ۯHn\y[O :bPG(LKQǏvP a |M<*gЁ4%[Ϯ|=\OjsBYc`);Ky_4N]\c!x%۹ + spin_unlock(&inode_lock); + __wait_on_bit(wqh, &wq, &inode->i_state, __I_LOCK, + inode_wait, TASK_UNINTERRUPTIBLE); + iput(inode); + spin_lock(&inode_lock); + } while (inode->i_state & I_LOCK); } return __sync_single_inode(inode, wbc); } diff -puN fs/inode.c~eliminate-inode-waitqueue-hashtable fs/inode.c --- 25/fs/inode.c~eliminate-inode-waitqueue-hashtable 2004-09-21 01:57:14.064299720 -0700 +++ 25-akpm/fs/inode.c 2004-09-21 01:57:14.074298200 -0700 @@ -1265,37 +1265,10 @@ void remove_dquot_ref(struct super_block #endif -/* - * Hashed waitqueues for wait_on_inode(). The table is pretty small - the - * kernel doesn't lock many inodes at the same time. - */ -#define I_WAIT_TABLE_ORDER 3 -static struct i_wait_queue_head { - wait_queue_head_t wqh; -} ____cacheline_aligned_in_smp i_wait_queue_heads[1<i_state & I_LOCK) { - schedule(); - goto repeat; - } - remove_wait_queue(wq, &wait); - __set_current_state(TASK_RUNNING); + schedule(); + return 0; } /* @@ -1304,36 +1277,39 @@ repeat: * that it isn't found. This is because iget will immediately call * ->read_inode, and we want to be sure that evidence of the deletion is found * by ->read_inode. - * - * This call might return early if an inode which shares the waitq is woken up. - * This is most easily handled by the caller which will loop around again - * looking for the inode. - * * This is called with inode_lock held. */ static void __wait_on_freeing_inode(struct inode *inode) { - DECLARE_WAITQUEUE(wait, current); - wait_queue_head_t *wq = i_waitq_head(inode); + wait_queue_head_t *wq; + DEFINE_WAIT_BIT(wait, &inode->i_state, __I_LOCK); - add_wait_queue(wq, &wait); - set_current_state(TASK_UNINTERRUPTIBLE); + /* + * I_FREEING and I_CLEAR are cleared in process context under + * inode_lock, so we have to give the tasks who would clear them + * a chance to run and acquire inode_lock. + */ + if (!(inode->i_state & I_LOCK)) { + spin_unlock(&inode_lock); + yield(); + spin_lock(&inode_lock); + return; + } + wq = bit_waitqueue(&inode->i_state, __I_LOCK); + prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE); spin_unlock(&inode_lock); schedule(); - remove_wait_queue(wq, &wait); + finish_wait(wq, &wait.wait); spin_lock(&inode_lock); } void wake_up_inode(struct inode *inode) { - wait_queue_head_t *wq = i_waitq_head(inode); - /* * Prevent speculative execution through spin_unlock(&inode_lock); */ smp_mb(); - if (waitqueue_active(wq)) - wake_up_all(wq); + wake_up_bit(&inode->i_state, __I_LOCK); } EXPORT_SYMBOL(wake_up_inode); @@ -1369,11 +1345,6 @@ void __init inode_init_early(void) void __init inode_init(unsigned long mempages) { - int i; - - for (i = 0; i < ARRAY_SIZE(i_wait_queue_heads); i++) - init_waitqueue_head(&i_wait_queue_heads[i].wqh); - /* inode slab cache */ inode_cachep = kmem_cache_create("inode_cache", sizeof(struct inode), 0, SLAB_PANIC, init_once, NULL); diff -puN include/linux/fs.h~eliminate-inode-waitqueue-hashtable include/linux/fs.h --- 25/include/linux/fs.h~eliminate-inode-waitqueue-hashtable 2004-09-21 01:57:14.066299416 -0700 +++ 25-akpm/include/linux/fs.h 2004-09-21 01:57:14.076297896 -0700 @@ -1056,7 +1056,8 @@ struct super_operations { #define I_DIRTY_SYNC 1 /* Not dirty enough for O_DATASYNC */ #define I_DIRTY_DATASYNC 2 /* Data-related inode changes pending */ #define I_DIRTY_PAGES 4 /* Data-related inode changes pending */ -#define I_LOCK 8 +#define __I_LOCK 3 +#define I_LOCK (1 << __I_LOCK) #define I_FREEING 16 #define I_CLEAR 32 #define I_NEW 64 diff -puN include/linux/writeback.h~eliminate-inode-waitqueue-hashtable include/linux/writeback.h --- 25/include/linux/writeback.h~eliminate-inode-waitqueue-hashtable 2004-09-21 01:57:14.067299264 -0700 +++ 25-akpm/include/linux/writeback.h 2004-09-21 01:57:14.076297896 -0700 @@ -68,7 +68,7 @@ struct writeback_control { */ void writeback_inodes(struct writeback_control *wbc); void wake_up_inode(struct inode *inode); -void __wait_on_inode(struct inode * inode); +int inode_wait(void *); void sync_inodes_sb(struct super_block *, int wait); void sync_inodes(int wait); @@ -76,8 +76,8 @@ void sync_inodes(int wait); static inline void wait_on_inode(struct inode *inode) { might_sleep(); - if (inode->i_state & I_LOCK) - __wait_on_inode(inode); + wait_on_bit(&inode->i_state, __I_LOCK, inode_wait, + TASK_UNINTERRUPTIBLE); } /* diff -puN kernel/wait.c~eliminate-inode-waitqueue-hashtable kernel/wait.c --- 25/kernel/wait.c~eliminate-inode-waitqueue-hashtable 2004-09-21 01:57:14.069298960 -0700 +++ 25-akpm/kernel/wait.c 2004-09-21 01:57:14.077297744 -0700 @@ -7,6 +7,7 @@ #include #include #include +#include #include #include _