diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c index 44e20e578ba0..b306265caa33 100644 --- a/fs/xfs/linux-2.6/xfs_buf.c +++ b/fs/xfs/linux-2.6/xfs_buf.c @@ -1778,6 +1778,35 @@ xfs_buf_delwri_dequeue( trace_xfs_buf_delwri_dequeue(bp, _RET_IP_); } +/* + * If a delwri buffer needs to be pushed before it has aged out, then promote + * it to the head of the delwri queue so that it will be flushed on the next + * xfsbufd run. We do this by resetting the queuetime of the buffer to be older + * than the age currently needed to flush the buffer. Hence the next time the + * xfsbufd sees it is guaranteed to be considered old enough to flush. + */ +void +xfs_buf_delwri_promote( + struct xfs_buf *bp) +{ + struct xfs_buftarg *btp = bp->b_target; + long age = xfs_buf_age_centisecs * msecs_to_jiffies(10) + 1; + + ASSERT(bp->b_flags & XBF_DELWRI); + ASSERT(bp->b_flags & _XBF_DELWRI_Q); + + /* + * Check the buffer age before locking the delayed write queue as we + * don't need to promote buffers that are already past the flush age. + */ + if (bp->b_queuetime < jiffies - age) + return; + bp->b_queuetime = jiffies - age; + spin_lock(&btp->bt_delwrite_lock); + list_move(&bp->b_list, &btp->bt_delwrite_queue); + spin_unlock(&btp->bt_delwrite_lock); +} + STATIC void xfs_buf_runall_queues( struct workqueue_struct *queue) diff --git a/fs/xfs/linux-2.6/xfs_buf.h b/fs/xfs/linux-2.6/xfs_buf.h index ea8c198f0c39..be45e8c5768d 100644 --- a/fs/xfs/linux-2.6/xfs_buf.h +++ b/fs/xfs/linux-2.6/xfs_buf.h @@ -266,6 +266,7 @@ extern int xfs_buf_ispin(xfs_buf_t *); /* Delayed Write Buffer Routines */ extern void xfs_buf_delwri_dequeue(xfs_buf_t *); +extern void xfs_buf_delwri_promote(xfs_buf_t *); /* Buffer Daemon Setup Routines */ extern int xfs_buf_init(void); @@ -395,6 +396,7 @@ extern void xfs_free_buftarg(struct xfs_mount *, struct xfs_buftarg *); extern void xfs_wait_buftarg(xfs_buftarg_t *); extern int xfs_setsize_buftarg(xfs_buftarg_t *, unsigned int, unsigned int); extern int xfs_flush_buftarg(xfs_buftarg_t *, int); + #ifdef CONFIG_KDB_MODULES extern struct list_head *xfs_get_buftarg_list(void); #endif diff --git a/fs/xfs/linux-2.6/xfs_trace.h b/fs/xfs/linux-2.6/xfs_trace.h index 1bb09e70b2eb..a4574dcf5065 100644 --- a/fs/xfs/linux-2.6/xfs_trace.h +++ b/fs/xfs/linux-2.6/xfs_trace.h @@ -483,6 +483,7 @@ DEFINE_BUF_ITEM_EVENT(xfs_buf_item_unlock); DEFINE_BUF_ITEM_EVENT(xfs_buf_item_unlock_stale); DEFINE_BUF_ITEM_EVENT(xfs_buf_item_committed); DEFINE_BUF_ITEM_EVENT(xfs_buf_item_push); +DEFINE_BUF_ITEM_EVENT(xfs_buf_item_pushbuf); DEFINE_BUF_ITEM_EVENT(xfs_trans_get_buf); DEFINE_BUF_ITEM_EVENT(xfs_trans_get_buf_recur); DEFINE_BUF_ITEM_EVENT(xfs_trans_getsb); diff --git a/fs/xfs/quota/xfs_dquot_item.c b/fs/xfs/quota/xfs_dquot_item.c index 1b564376d50c..dda0fb045c8a 100644 --- a/fs/xfs/quota/xfs_dquot_item.c +++ b/fs/xfs/quota/xfs_dquot_item.c @@ -212,18 +212,10 @@ xfs_qm_dquot_logitem_pushbuf( xfs_dquot_t *dqp; xfs_mount_t *mp; xfs_buf_t *bp; - uint dopush; dqp = qip->qli_dquot; ASSERT(XFS_DQ_IS_LOCKED(dqp)); - /* - * The qli_pushbuf_flag keeps others from - * trying to duplicate our effort. - */ - ASSERT(qip->qli_pushbuf_flag != 0); - ASSERT(qip->qli_push_owner == current_pid()); - /* * If flushlock isn't locked anymore, chances are that the * inode flush completed and the inode was taken off the AIL. @@ -231,47 +223,20 @@ xfs_qm_dquot_logitem_pushbuf( */ if (completion_done(&dqp->q_flush) || ((qip->qli_item.li_flags & XFS_LI_IN_AIL) == 0)) { - qip->qli_pushbuf_flag = 0; xfs_dqunlock(dqp); return; } mp = dqp->q_mount; bp = xfs_incore(mp->m_ddev_targp, qip->qli_format.qlf_blkno, XFS_QI_DQCHUNKLEN(mp), XBF_TRYLOCK); - if (bp != NULL) { - if (XFS_BUF_ISDELAYWRITE(bp)) { - dopush = ((qip->qli_item.li_flags & XFS_LI_IN_AIL) && - !completion_done(&dqp->q_flush)); - qip->qli_pushbuf_flag = 0; - xfs_dqunlock(dqp); - - if (XFS_BUF_ISPINNED(bp)) - xfs_log_force(mp, 0); - - if (dopush) { - int error; -#ifdef XFSRACEDEBUG - delay_for_intr(); - delay(300); -#endif - error = xfs_bawrite(mp, bp); - if (error) - xfs_fs_cmn_err(CE_WARN, mp, - "xfs_qm_dquot_logitem_pushbuf: pushbuf error %d on qip %p, bp %p", - error, qip, bp); - } else { - xfs_buf_relse(bp); - } - } else { - qip->qli_pushbuf_flag = 0; - xfs_dqunlock(dqp); - xfs_buf_relse(bp); - } - return; - } - - qip->qli_pushbuf_flag = 0; xfs_dqunlock(dqp); + if (!bp) + return; + if (XFS_BUF_ISDELAYWRITE(bp)) + xfs_buf_delwri_promote(bp); + xfs_buf_relse(bp); + return; + } /* @@ -289,50 +254,24 @@ xfs_qm_dquot_logitem_trylock( xfs_dq_logitem_t *qip) { xfs_dquot_t *dqp; - uint retval; dqp = qip->qli_dquot; if (atomic_read(&dqp->q_pincount) > 0) - return (XFS_ITEM_PINNED); + return XFS_ITEM_PINNED; if (! xfs_qm_dqlock_nowait(dqp)) - return (XFS_ITEM_LOCKED); + return XFS_ITEM_LOCKED; - retval = XFS_ITEM_SUCCESS; if (!xfs_dqflock_nowait(dqp)) { /* - * The dquot is already being flushed. It may have been - * flushed delayed write, however, and we don't want to - * get stuck waiting for that to complete. So, we want to check - * to see if we can lock the dquot's buffer without sleeping. - * If we can and it is marked for delayed write, then we - * hold it and send it out from the push routine. We don't - * want to do that now since we might sleep in the device - * strategy routine. We also don't want to grab the buffer lock - * here because we'd like not to call into the buffer cache - * while holding the AIL lock. - * Make sure to only return PUSHBUF if we set pushbuf_flag - * ourselves. If someone else is doing it then we don't - * want to go to the push routine and duplicate their efforts. + * dquot has already been flushed to the backing buffer, + * leave it locked, pushbuf routine will unlock it. */ - if (qip->qli_pushbuf_flag == 0) { - qip->qli_pushbuf_flag = 1; - ASSERT(qip->qli_format.qlf_blkno == dqp->q_blkno); -#ifdef DEBUG - qip->qli_push_owner = current_pid(); -#endif - /* - * The dquot is left locked. - */ - retval = XFS_ITEM_PUSHBUF; - } else { - retval = XFS_ITEM_FLUSHING; - xfs_dqunlock_nonotify(dqp); - } + return XFS_ITEM_PUSHBUF; } ASSERT(qip->qli_item.li_flags & XFS_LI_IN_AIL); - return (retval); + return XFS_ITEM_SUCCESS; } diff --git a/fs/xfs/quota/xfs_dquot_item.h b/fs/xfs/quota/xfs_dquot_item.h index 5a632531f843..5acae2ada70b 100644 --- a/fs/xfs/quota/xfs_dquot_item.h +++ b/fs/xfs/quota/xfs_dquot_item.h @@ -27,10 +27,6 @@ typedef struct xfs_dq_logitem { xfs_log_item_t qli_item; /* common portion */ struct xfs_dquot *qli_dquot; /* dquot ptr */ xfs_lsn_t qli_flush_lsn; /* lsn at last flush */ - unsigned short qli_pushbuf_flag; /* 1 bit used in push_ail */ -#ifdef DEBUG - uint64_t qli_push_owner; -#endif xfs_dq_logformat_t qli_format; /* logged structure */ } xfs_dq_logitem_t; diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c index e0a11583ce5a..f3c49e69eab9 100644 --- a/fs/xfs/xfs_buf_item.c +++ b/fs/xfs/xfs_buf_item.c @@ -467,8 +467,10 @@ xfs_buf_item_unpin_remove( /* * This is called to attempt to lock the buffer associated with this * buf log item. Don't sleep on the buffer lock. If we can't get - * the lock right away, return 0. If we can get the lock, pull the - * buffer from the free list, mark it busy, and return 1. + * the lock right away, return 0. If we can get the lock, take a + * reference to the buffer. If this is a delayed write buffer that + * needs AIL help to be written back, invoke the pushbuf routine + * rather than the normal success path. */ STATIC uint xfs_buf_item_trylock( @@ -477,24 +479,18 @@ xfs_buf_item_trylock( xfs_buf_t *bp; bp = bip->bli_buf; - - if (XFS_BUF_ISPINNED(bp)) { + if (XFS_BUF_ISPINNED(bp)) return XFS_ITEM_PINNED; - } - - if (!XFS_BUF_CPSEMA(bp)) { + if (!XFS_BUF_CPSEMA(bp)) return XFS_ITEM_LOCKED; - } - /* - * Remove the buffer from the free list. Only do this - * if it's on the free list. Private buffers like the - * superblock buffer are not. - */ + /* take a reference to the buffer. */ XFS_BUF_HOLD(bp); ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); trace_xfs_buf_item_trylock(bip); + if (XFS_BUF_ISDELAYWRITE(bp)) + return XFS_ITEM_PUSHBUF; return XFS_ITEM_SUCCESS; } @@ -626,11 +622,9 @@ xfs_buf_item_committed( } /* - * This is called to asynchronously write the buffer associated with this - * buf log item out to disk. The buffer will already have been locked by - * a successful call to xfs_buf_item_trylock(). If the buffer still has - * B_DELWRI set, then get it going out to disk with a call to bawrite(). - * If not, then just release the buffer. + * The buffer is locked, but is not a delayed write buffer. This happens + * if we race with IO completion and hence we don't want to try to write it + * again. Just release the buffer. */ STATIC void xfs_buf_item_push( @@ -642,17 +636,29 @@ xfs_buf_item_push( trace_xfs_buf_item_push(bip); bp = bip->bli_buf; + ASSERT(!XFS_BUF_ISDELAYWRITE(bp)); + xfs_buf_relse(bp); +} - if (XFS_BUF_ISDELAYWRITE(bp)) { - int error; - error = xfs_bawrite(bip->bli_item.li_mountp, bp); - if (error) - xfs_fs_cmn_err(CE_WARN, bip->bli_item.li_mountp, - "xfs_buf_item_push: pushbuf error %d on bip %p, bp %p", - error, bip, bp); - } else { - xfs_buf_relse(bp); - } +/* + * The buffer is locked and is a delayed write buffer. Promote the buffer + * in the delayed write queue as the caller knows that they must invoke + * the xfsbufd to get this buffer written. We have to unlock the buffer + * to allow the xfsbufd to write it, too. + */ +STATIC void +xfs_buf_item_pushbuf( + xfs_buf_log_item_t *bip) +{ + xfs_buf_t *bp; + + ASSERT(!(bip->bli_flags & XFS_BLI_STALE)); + trace_xfs_buf_item_pushbuf(bip); + + bp = bip->bli_buf; + ASSERT(XFS_BUF_ISDELAYWRITE(bp)); + xfs_buf_delwri_promote(bp); + xfs_buf_relse(bp); } /* ARGSUSED */ @@ -677,7 +683,7 @@ static struct xfs_item_ops xfs_buf_item_ops = { .iop_committed = (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t)) xfs_buf_item_committed, .iop_push = (void(*)(xfs_log_item_t*))xfs_buf_item_push, - .iop_pushbuf = NULL, + .iop_pushbuf = (void(*)(xfs_log_item_t*))xfs_buf_item_pushbuf, .iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t)) xfs_buf_item_committing }; diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c index 207553e82954..d4dc063111f8 100644 --- a/fs/xfs/xfs_inode_item.c +++ b/fs/xfs/xfs_inode_item.c @@ -602,33 +602,20 @@ xfs_inode_item_trylock( if (!xfs_iflock_nowait(ip)) { /* - * If someone else isn't already trying to push the inode - * buffer, we get to do it. + * inode has already been flushed to the backing buffer, + * leave it locked in shared mode, pushbuf routine will + * unlock it. */ - if (iip->ili_pushbuf_flag == 0) { - iip->ili_pushbuf_flag = 1; -#ifdef DEBUG - iip->ili_push_owner = current_pid(); -#endif - /* - * Inode is left locked in shared mode. - * Pushbuf routine gets to unlock it. - */ - return XFS_ITEM_PUSHBUF; - } else { - /* - * We hold the AIL lock, so we must specify the - * NONOTIFY flag so that we won't double trip. - */ - xfs_iunlock(ip, XFS_ILOCK_SHARED|XFS_IUNLOCK_NONOTIFY); - return XFS_ITEM_FLUSHING; - } - /* NOTREACHED */ + return XFS_ITEM_PUSHBUF; } /* Stale items should force out the iclog */ if (ip->i_flags & XFS_ISTALE) { xfs_ifunlock(ip); + /* + * we hold the AIL lock - notify the unlock routine of this + * so it doesn't try to get the lock again. + */ xfs_iunlock(ip, XFS_ILOCK_SHARED|XFS_IUNLOCK_NONOTIFY); return XFS_ITEM_PINNED; } @@ -746,11 +733,8 @@ xfs_inode_item_committed( * This gets called by xfs_trans_push_ail(), when IOP_TRYLOCK * failed to get the inode flush lock but did get the inode locked SHARED. * Here we're trying to see if the inode buffer is incore, and if so whether it's - * marked delayed write. If that's the case, we'll initiate a bawrite on that - * buffer to expedite the process. - * - * We aren't holding the AIL lock (or the flush lock) when this gets called, - * so it is inherently race-y. + * marked delayed write. If that's the case, we'll promote it and that will + * allow the caller to write the buffer by triggering the xfsbufd to run. */ STATIC void xfs_inode_item_pushbuf( @@ -759,26 +743,16 @@ xfs_inode_item_pushbuf( xfs_inode_t *ip; xfs_mount_t *mp; xfs_buf_t *bp; - uint dopush; ip = iip->ili_inode; - ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED)); - /* - * The ili_pushbuf_flag keeps others from - * trying to duplicate our effort. - */ - ASSERT(iip->ili_pushbuf_flag != 0); - ASSERT(iip->ili_push_owner == current_pid()); - /* * If a flush is not in progress anymore, chances are that the * inode was taken off the AIL. So, just get out. */ if (completion_done(&ip->i_flush) || ((iip->ili_item.li_flags & XFS_LI_IN_AIL) == 0)) { - iip->ili_pushbuf_flag = 0; xfs_iunlock(ip, XFS_ILOCK_SHARED); return; } @@ -787,53 +761,12 @@ xfs_inode_item_pushbuf( bp = xfs_incore(mp->m_ddev_targp, iip->ili_format.ilf_blkno, iip->ili_format.ilf_len, XBF_TRYLOCK); - if (bp != NULL) { - if (XFS_BUF_ISDELAYWRITE(bp)) { - /* - * We were racing with iflush because we don't hold - * the AIL lock or the flush lock. However, at this point, - * we have the buffer, and we know that it's dirty. - * So, it's possible that iflush raced with us, and - * this item is already taken off the AIL. - * If not, we can flush it async. - */ - dopush = ((iip->ili_item.li_flags & XFS_LI_IN_AIL) && - !completion_done(&ip->i_flush)); - iip->ili_pushbuf_flag = 0; - xfs_iunlock(ip, XFS_ILOCK_SHARED); - - trace_xfs_inode_item_push(bp, _RET_IP_); - - if (XFS_BUF_ISPINNED(bp)) - xfs_log_force(mp, 0); - - if (dopush) { - int error; - error = xfs_bawrite(mp, bp); - if (error) - xfs_fs_cmn_err(CE_WARN, mp, - "xfs_inode_item_pushbuf: pushbuf error %d on iip %p, bp %p", - error, iip, bp); - } else { - xfs_buf_relse(bp); - } - } else { - iip->ili_pushbuf_flag = 0; - xfs_iunlock(ip, XFS_ILOCK_SHARED); - xfs_buf_relse(bp); - } - return; - } - /* - * We have to be careful about resetting pushbuf flag too early (above). - * Even though in theory we can do it as soon as we have the buflock, - * we don't want others to be doing work needlessly. They'll come to - * this function thinking that pushing the buffer is their - * responsibility only to find that the buffer is still locked by - * another doing the same thing - */ - iip->ili_pushbuf_flag = 0; xfs_iunlock(ip, XFS_ILOCK_SHARED); + if (!bp) + return; + if (XFS_BUF_ISDELAYWRITE(bp)) + xfs_buf_delwri_promote(bp); + xfs_buf_relse(bp); return; } @@ -937,7 +870,6 @@ xfs_inode_item_init( /* We have zeroed memory. No need ... iip->ili_extents_buf = NULL; - iip->ili_pushbuf_flag = 0; */ iip->ili_format.ilf_type = XFS_LI_INODE; diff --git a/fs/xfs/xfs_inode_item.h b/fs/xfs/xfs_inode_item.h index cc8df1ac7783..9a467958ecdd 100644 --- a/fs/xfs/xfs_inode_item.h +++ b/fs/xfs/xfs_inode_item.h @@ -144,12 +144,6 @@ typedef struct xfs_inode_log_item { data exts */ struct xfs_bmbt_rec *ili_aextents_buf; /* array of logged attr exts */ - unsigned int ili_pushbuf_flag; /* one bit used in push_ail */ - -#ifdef DEBUG - uint64_t ili_push_owner; /* one who sets pushbuf_flag - above gets to push the buf */ -#endif #ifdef XFS_TRANS_DEBUG int ili_root_size; char *ili_orig_root; diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index ca64f33c63a3..c93e3a102857 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -861,8 +861,7 @@ typedef struct xfs_item_ops { #define XFS_ITEM_SUCCESS 0 #define XFS_ITEM_PINNED 1 #define XFS_ITEM_LOCKED 2 -#define XFS_ITEM_FLUSHING 3 -#define XFS_ITEM_PUSHBUF 4 +#define XFS_ITEM_PUSHBUF 3 /* * This structure is used to maintain a list of block ranges that have been diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c index d7b1af8a832d..e799824f7245 100644 --- a/fs/xfs/xfs_trans_ail.c +++ b/fs/xfs/xfs_trans_ail.c @@ -253,6 +253,7 @@ xfsaild_push( int flush_log, count, stuck; xfs_mount_t *mp = ailp->xa_mount; struct xfs_ail_cursor *cur = &ailp->xa_cursors; + int push_xfsbufd = 0; spin_lock(&ailp->xa_lock); xfs_trans_ail_cursor_init(ailp, cur); @@ -308,6 +309,7 @@ xfsaild_push( XFS_STATS_INC(xs_push_ail_pushbuf); IOP_PUSHBUF(lip); last_pushed_lsn = lsn; + push_xfsbufd = 1; break; case XFS_ITEM_PINNED: @@ -322,12 +324,6 @@ xfsaild_push( stuck++; break; - case XFS_ITEM_FLUSHING: - XFS_STATS_INC(xs_push_ail_flushing); - last_pushed_lsn = lsn; - stuck++; - break; - default: ASSERT(0); break; @@ -374,6 +370,11 @@ xfsaild_push( xfs_log_force(mp, 0); } + if (push_xfsbufd) { + /* we've got delayed write buffers to flush */ + wake_up_process(mp->m_ddev_targp->bt_task); + } + if (!count) { /* We're past our target or empty, so idle */ last_pushed_lsn = 0;