From 4560e78f40cb55bd2ea8f1ef4001c5baa88531c7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 7 Feb 2017 14:07:58 -0800 Subject: [PATCH] xfs: don't block the log commit handler for discards Instead we submit the discard requests and use another workqueue to release the extents from the extent busy list. Signed-off-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_discard.c | 29 --------------- fs/xfs/xfs_discard.h | 1 - fs/xfs/xfs_log_cil.c | 84 ++++++++++++++++++++++++++++++++++++++----- fs/xfs/xfs_log_priv.h | 1 + fs/xfs/xfs_mount.c | 1 + fs/xfs/xfs_super.c | 8 +++++ fs/xfs/xfs_super.h | 2 ++ 7 files changed, 88 insertions(+), 38 deletions(-) diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c index 4ff499aa7338..d796ffac7296 100644 --- a/fs/xfs/xfs_discard.c +++ b/fs/xfs/xfs_discard.c @@ -208,32 +208,3 @@ xfs_ioc_trim( return -EFAULT; return 0; } - -int -xfs_discard_extents( - struct xfs_mount *mp, - struct list_head *list) -{ - struct xfs_extent_busy *busyp; - int error = 0; - - list_for_each_entry(busyp, list, list) { - trace_xfs_discard_extent(mp, busyp->agno, busyp->bno, - busyp->length); - - error = blkdev_issue_discard(mp->m_ddev_targp->bt_bdev, - XFS_AGB_TO_DADDR(mp, busyp->agno, busyp->bno), - XFS_FSB_TO_BB(mp, busyp->length), - GFP_NOFS, 0); - if (error && error != -EOPNOTSUPP) { - xfs_info(mp, - "discard failed for extent [0x%llx,%u], error %d", - (unsigned long long)busyp->bno, - busyp->length, - error); - return error; - } - } - - return 0; -} diff --git a/fs/xfs/xfs_discard.h b/fs/xfs/xfs_discard.h index 344879aea646..0f070f9e44e1 100644 --- a/fs/xfs/xfs_discard.h +++ b/fs/xfs/xfs_discard.h @@ -5,6 +5,5 @@ struct fstrim_range; struct list_head; extern int xfs_ioc_trim(struct xfs_mount *, struct fstrim_range __user *); -extern int xfs_discard_extents(struct xfs_mount *, struct list_head *); #endif /* XFS_DISCARD_H */ diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c index a4ab192e1792..82f1cbcc4de1 100644 --- a/fs/xfs/xfs_log_cil.c +++ b/fs/xfs/xfs_log_cil.c @@ -30,6 +30,9 @@ #include "xfs_trans_priv.h" #include "xfs_log.h" #include "xfs_log_priv.h" +#include "xfs_trace.h" + +struct workqueue_struct *xfs_discard_wq; /* * Allocate a new ticket. Failing to get a new ticket makes it really hard to @@ -491,6 +494,75 @@ xlog_cil_free_logvec( } } +static void +xlog_discard_endio_work( + struct work_struct *work) +{ + struct xfs_cil_ctx *ctx = + container_of(work, struct xfs_cil_ctx, discard_endio_work); + struct xfs_mount *mp = ctx->cil->xc_log->l_mp; + + xfs_extent_busy_clear(mp, &ctx->busy_extents, false); + kmem_free(ctx); +} + +/* + * Queue up the actual completion to a thread to avoid IRQ-safe locking for + * pagb_lock. Note that we need a unbounded workqueue, otherwise we might + * get the execution delayed up to 30 seconds for weird reasons. + */ +static void +xlog_discard_endio( + struct bio *bio) +{ + struct xfs_cil_ctx *ctx = bio->bi_private; + + INIT_WORK(&ctx->discard_endio_work, xlog_discard_endio_work); + queue_work(xfs_discard_wq, &ctx->discard_endio_work); +} + +static void +xlog_discard_busy_extents( + struct xfs_mount *mp, + struct xfs_cil_ctx *ctx) +{ + struct list_head *list = &ctx->busy_extents; + struct xfs_extent_busy *busyp; + struct bio *bio = NULL; + struct blk_plug plug; + int error = 0; + + ASSERT(mp->m_flags & XFS_MOUNT_DISCARD); + + blk_start_plug(&plug); + list_for_each_entry(busyp, list, list) { + trace_xfs_discard_extent(mp, busyp->agno, busyp->bno, + busyp->length); + + error = __blkdev_issue_discard(mp->m_ddev_targp->bt_bdev, + XFS_AGB_TO_DADDR(mp, busyp->agno, busyp->bno), + XFS_FSB_TO_BB(mp, busyp->length), + GFP_NOFS, 0, &bio); + if (error && error != -EOPNOTSUPP) { + xfs_info(mp, + "discard failed for extent [0x%llx,%u], error %d", + (unsigned long long)busyp->bno, + busyp->length, + error); + break; + } + } + + if (bio) { + bio->bi_private = ctx; + bio->bi_end_io = xlog_discard_endio; + submit_bio(bio); + } else { + xlog_discard_endio_work(&ctx->discard_endio_work); + } + blk_finish_plug(&plug); +} + /* * Mark all items committed and clear busy extents. We free the log vector * chains in a separate pass so that we unpin the log items as quickly as @@ -525,14 +597,10 @@ xlog_cil_committed( xlog_cil_free_logvec(ctx->lv_chain); - if (!list_empty(&ctx->busy_extents)) { - ASSERT(mp->m_flags & XFS_MOUNT_DISCARD); - - xfs_discard_extents(mp, &ctx->busy_extents); - xfs_extent_busy_clear(mp, &ctx->busy_extents, false); - } - - kmem_free(ctx); + if (!list_empty(&ctx->busy_extents)) + xlog_discard_busy_extents(mp, ctx); + else + kmem_free(ctx); } /* diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h index 2b6eec52178e..c2604a5366f2 100644 --- a/fs/xfs/xfs_log_priv.h +++ b/fs/xfs/xfs_log_priv.h @@ -257,6 +257,7 @@ struct xfs_cil_ctx { struct xfs_log_vec *lv_chain; /* logvecs being pushed */ struct xfs_log_callback log_cb; /* completion callback hook. */ struct list_head committing; /* ctx committing list */ + struct work_struct discard_endio_work; }; /* diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index 566eb79666ad..450bde68bb75 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -1085,6 +1085,7 @@ xfs_unmountfs( * any discard operation. */ xfs_extent_busy_wait_all(mp); + flush_workqueue(xfs_discard_wq); /* * We now need to tell the world we are unmounting. This will allow diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index eecbaac08eba..890862f2447c 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1956,12 +1956,20 @@ xfs_init_workqueues(void) if (!xfs_alloc_wq) return -ENOMEM; + xfs_discard_wq = alloc_workqueue("xfsdiscard", WQ_UNBOUND, 0); + if (!xfs_discard_wq) + goto out_free_alloc_wq; + return 0; +out_free_alloc_wq: + destroy_workqueue(xfs_alloc_wq); + return -ENOMEM; } STATIC void xfs_destroy_workqueues(void) { + destroy_workqueue(xfs_discard_wq); destroy_workqueue(xfs_alloc_wq); } diff --git a/fs/xfs/xfs_super.h b/fs/xfs/xfs_super.h index b6418abd85ad..5f2f32408011 100644 --- a/fs/xfs/xfs_super.h +++ b/fs/xfs/xfs_super.h @@ -73,6 +73,8 @@ extern const struct quotactl_ops xfs_quotactl_operations; extern void xfs_reinit_percpu_counters(struct xfs_mount *mp); +extern struct workqueue_struct *xfs_discard_wq; + #define XFS_M(sb) ((struct xfs_mount *)((sb)->s_fs_info)) #endif /* __XFS_SUPER_H__ */